| R Factors | 
              | R Plasmids use R Factors | 
              | R Repetitive Sequence use Terminal Repeat Sequences | 
              | R+D use Scientific Research and Technological Development | 
              | R-SNARE Proteins | 
              | R-Type Calcium Channels use Calcium Channels, R-Type | 
              | rab G-Proteins use rab GTP-Binding Proteins | 
              | rab GTP-Binding Proteins | 
              | rab GTPases use rab GTP-Binding Proteins | 
              | rab1 GTP-Binding Proteins | 
              | rab1A GTP-Binding Protein use rab1 GTP-Binding Proteins | 
              | rab2 GTP-Binding Protein | 
              | rab3 GTP-Binding Proteins | 
              | rab3A GTP-Binding Protein | 
              | rab4 GTP-Binding Proteins | 
              | rab4A GTP-Binding Protein use rab4 GTP-Binding Proteins | 
              | rab5 GTP-Binding Proteins | 
              | rab5A GTP-Binding Protein use rab5 GTP-Binding Proteins | 
              | Rabbit Aorta Contracting Substance use Thromboxane A2 | 
              | Rabbit coronavirus use Coronavirus | 
              | Rabbit fibroma virus use Fibroma Virus, Rabbit | 
              | Rabbit hemorrhagic disease virus use Hemorrhagic Disease Virus, Rabbit | 
              | Rabbit, Domestic use Rabbits | 
              | Rabbitpox virus use Vaccinia virus | 
              | Rabbits | 
              | Rabdosia | 
              | Rabies | 
              | Rabies Vaccines | 
              | Rabies virus | 
              | rac GTP-Binding Proteins | 
              | rac Proteins use rac GTP-Binding Proteins | 
              | rac1 GTP-Binding Protein | 
              | Raccoon Dogs | 
              | Raccoon parvovirus use Parvovirus | 
              | Raccoons | 
              | Race and Health use Ethnic Group and Health | 
              | Race or Color Distribution use Race or Ethnic Group Distribution | 
              | Race or Ethnic Group Distribution | 
              | Race Relations | 
              | Racemases use Racemases and Epimerases | 
              | Racemases and Epimerases | 
              | Racemomycins use Streptothricins | 
              | Rachischisis use Spinal Dysraphism | 
              | Rachitis use Rickets | 
              | Racism use Prejudice | 
              | Raclopride | 
              | Racquet Sports | 
              | Racquetball use Racquet Sports | 
              | Rad51 Recombinase | 
              | Rad52 DNA Repair and Recombination Protein | 
              | Radar | 
              | Radial Artery | 
              | Radial Circulation Filters use Radial Filters | 
              | Radial Filters | 
              | Radial Keratotomy use Keratotomy, Radial | 
              | Radial Nerve | 
              | Radial Neuropathy | 
              | Radiant Warmers, Infant use Incubators, Infant | 
              | Radiation | 
              | Radiation Accidents use Radioactive Hazard Release | 
              | Radiation Biology use Radiobiology | 
              | Radiation Chimera | 
              | Radiation Control | 
              | Radiation Diseases | 
              | Radiation Dosage | 
              | Radiation Dosimetry use Radiometry | 
              | Radiation Effects | 
              | Radiation Equipment and Supplies | 
              | Radiation Exposure | 
              | Radiation Exposure Measure | 
              | Radiation Exposure Pathways | 
              | Radiation Genetics | 
              | Radiation Hybrid Mapping | 
              | Radiation Hybrid Maps use Radiation Hybrid Mapping | 
              | Radiation Hybrids use Radiation Hybrid Mapping | 
              | Radiation Injuries | 
              | Radiation Injuries, Experimental | 
              | Radiation Leukemia Virus | 
              | Radiation Measurement | 
              | Radiation Monitoring | 
              | Radiation Oncology | 
              | Radiation Pneumonitis | 
              | Radiation Protection | 
              | Radiation Recall Dermatitis use Radiodermatitis | 
              | Radiation Risks | 
              | Radiation Safety Guidelines use Guidelines for Radiological Safety | 
              | Radiation Safety Manual use Guidelines for Radiological Safety | 
              | Radiation Safety Standards use Guidelines for Radiological Safety | 
              | Radiation Sensitivity use Radiation Tolerance | 
              | Radiation Shielding use Shielding against Radiation | 
              | Radiation Sickness use Radiation Injuries | 
              | Radiation Sources | 
              | Radiation Syndrome use Radiation Injuries | 
              | Radiation Therapy, Computer-Assisted use Radiotherapy, Computer-Assisted | 
              | Radiation Tolerance | 
              | Radiation, Ionizing | 
              | Radiation, Nonionizing | 
              | Radiation, Visible use Light | 
              | Radiation, Whole-Body use Whole-Body Irradiation | 
              | Radiation-Induced Cancer use Neoplasms, Radiation-Induced | 
              | Radiation-Induced Dermatitis use Radiodermatitis | 
              | Radiation-Protective Agents | 
              | Radiation-Sensitizing Agents | 
              | Radical Neck Dissection use Neck Dissection | 
              | Radicular Cyst | 
              | Radiculitis use Radiculopathy | 
              | Radiculopathy | 
              | Radiesthesia | 
              | Radio | 
              | Radio Waves | 
              | Radioactive Accidents and Events | 
              | Radioactive Air Pollutants use Air Pollutants, Radioactive | 
              | Radioactive Confinement | 
              | Radioactive Decontamination | 
              | Radioactive Effluents | 
              | Radioactive Elements use Elements, Radioactive | 
              | Radioactive Emission | 
              | Radioactive Fallout | 
              | Radioactive Half-Life use Half-Life | 
              | Radioactive Hazard Release | 
              | Radioactive Isotopes use Radioisotopes | 
              | Radioactive Material | 
              | Radioactive Pollutants | 
              | Radioactive Pollution | 
              | Radioactive Rain use Radioactive Fallout | 
              | Radioactive Substances, Products and Materials | 
              | Radioactive Tracers | 
              | Radioactive Waste | 
              | Radioactivity | 
              | Radioallergosorbent Test | 
              | Radioautography use Autoradiography | 
              | Radiobiology | 
              | Radiocarpal Joint use Wrist Joint | 
              | Radiochemistry | 
              | Radiocinematography use Cineradiography | 
              | Radiodermatitis | 
              | Radiographic Film use X-Ray Film | 
              | Radiographic Image Enhancement | 
              | Radiographic Image Interpretation, Computer-Assisted | 
              | Radiographic Intensifying Screens use X-Ray Intensifying Screens | 
              | Radiographic Magnification | 
              | Radiographic Phantoms use Phantoms, Imaging | 
              | Radiography | 
              | Radiography, Abdominal | 
              | Radiography, Bitewing | 
              | Radiography, Dental | 
              | Radiography, Dental, Digital | 
              | Radiography, Dual-Energy Scanned Projection | 
              | Radiography, Insufflation use Pneumoradiography | 
              | Radiography, Interventional | 
              | Radiography, Panoramic | 
              | Radiography, Thoracic | 
              | Radioimmunoassay | 
              | Radioimmunoconjugates use Immunoconjugates | 
              | Radioimmunodetection | 
              | Radioimmunoimaging use Radioimmunodetection | 
              | Radioimmunoprecipitation Analysis use Radioimmunoprecipitation Assay | 
              | Radioimmunoprecipitation Assay | 
              | Radioimmunoscintigraphy use Radioimmunodetection | 
              | Radioimmunosorbent Assay of Allergens use Radioallergosorbent Test | 
              | Radioimmunosorbent Test | 
              | Radioimmunotherapy | 
              | Radioisotope Angiography use Radionuclide Angiography | 
              | Radioisotope Brachytherapy use Brachytherapy | 
              | Radioisotope Dilution Technique | 
              | Radioisotope Generators use Radionuclide Generators | 
              | Radioisotope Renography | 
              | Radioisotope Scanning use Radionuclide Imaging | 
              | Radioisotope Teletherapy | 
              | Radioisotopes | 
              | Radioligand Assay | 
              | Radiologic Health | 
              | Radiologic Phantoms use Phantoms, Imaging | 
              | Radiologic Physics use Health Physics | 
              | Radiologic Protection use Radiation Protection | 
              | Radiologic Surveillance use Radiological Surveillance | 
              | Radiological Safety Guidelines use Guidelines for Radiological Safety | 
              | Radiological Safety Manual use Guidelines for Radiological Safety | 
              | Radiological Safety Standards use Guidelines for Radiological Safety | 
              | Radiological Surveillance | 
              | Radiology | 
              | Radiology Department, Hospital | 
              | Radiology Information Systems | 
              | Radiology, Diagnostic X-Ray use Radiography | 
              | Radiology, Interventional | 
              | Radiology, Therapeutic use Radiation Oncology | 
              | Radiometric Dating | 
              | Radiometry | 
              | Radionuclide | 
              | Radionuclide Angiography | 
              | Radionuclide Angiography, First-Pass use Ventriculography, First-Pass | 
              | Radionuclide Angiography, Gated use Gated Blood-Pool Imaging | 
              | Radionuclide Generators | 
              | Radionuclide Imaging | 
              | Radionuclide Maximum Acceptable Concentration | 
              | Radionuclide Tomography, Computed use Tomography, Emission-Computed | 
              | Radionuclide Tomography, Single-Photon Emission-Computed use Tomography, Emission-Computed, Single-Photon | 
              | Radionuclide Ventriculography | 
              | Radionuclide Ventriculography, First-Pass use Ventriculography, First-Pass | 
              | Radionuclide Ventriculography, Gated use Gated Blood-Pool Imaging | 
              | Radionuclides use Radioisotopes | 
              | Radiopaque Media use Contrast Media | 
              | Radiopharmaceuticals | 
              | Radioprotective Agents use Radiation-Protective Agents | 
              | Radioreceptor Assay use Radioligand Assay | 
              | Radioselenomethionine use Selenomethionine | 
              | Radiosensitivity use Radiation Tolerance | 
              | Radiosensitizing Agents use Radiation-Sensitizing Agents | 
              | Radiosurgery | 
              | Radiotherapy | 
              | Radiotherapy Dosage | 
              | Radiotherapy Dose Fractionation use Dose Fractionation | 
              | Radiotherapy Planning, Computer-Assisted | 
              | Radiotherapy, Adjuvant | 
              | Radiotherapy, Computer-Assisted | 
              | Radiotherapy, Conformal | 
              | Radiotherapy, High-Energy | 
              | Radiotherapy, Intensity-Modulated | 
              | Radiotherapy, Interstitial use Brachytherapy | 
              | Radiotherapy, Intracavity use Brachytherapy | 
              | Radiotherapy, Lymphatic use Lymphatic Irradiation | 
              | Radiotherapy, Surface use Brachytherapy | 
              | Radiotherapy, Targeted use Radiotherapy | 
              | Radish use Raphanus | 
              | Radium | 
              | Radium Bromatum | 
              | Radium Metallicum | 
              | Radius | 
              | Radius Fractures | 
              | RadLV use Radiation Leukemia Virus | 
              | Radon | 
              | Radon Daughters | 
              | RAEB use Anemia, Refractory, with Excess of Blasts | 
              | Raeder Paratrigeminal Syndrome use Trigeminal Nerve Diseases | 
              | RAEM use Anemia, Refractory, with Excess of Blasts | 
              | raf Kinases | 
              | raf MAP Kinase Kinase Kinases use raf Kinases | 
              | Raffinose | 
              | Rafoxanide | 
              | RAG-1 Genes use Genes, RAG-1 | 
              | Rage | 
              | Ragweed use Ambrosia | 
              | Ragwort use Senecio | 
              | Rahnella | 
              | Rahnella aquatilis use Rahnella | 
              | RAIDD Signaling Adaptor Protein use CRADD Signaling Adaptor Protein | 
              | Raillietina use Cestoda | 
              | Raillietiniasis use Cestode Infections | 
              | Railroads | 
              | Rain | 
              | Rain Induction use Mist Catchment | 
              | Rain Measurement | 
              | Rain Stimulation use Mist Catchment | 
              | Rain, Acid use Acid Rain | 
              | Rain-Gauge use Precipitation Gauge | 
              | Rainfall use Atmospheric Precipitation | 
              | Rainfall Amount use Pluviometry | 
              | Rainfall Intensity use Precipitation Intensity | 
              | Rainfall-Runoff Relationship | 
              | Rainwater | 
              | Rainwater Catchment | 
              | Rainy Season | 
              | Raising of Poultry use Aviculture | 
              | Raisins use Vitis | 
              | Raja use Skates (Fish) | 
              | Rajania subsamarata | 
              | Rajidae use Skates (Fish) | 
              | Rajiformes use Skates (Fish) | 
              | ral A GTP-Binding Protein use ral GTP-Binding Proteins | 
              | ral GDP Dissociation Stimulator use ral Guanine Nucleotide Exchange Factor | 
              | ral GTP-Binding Proteins | 
              | ral Guanine Nucleotide Exchange Factor | 
              | Raleigh Waves use Surface Waves | 
              | Rales use Respiratory Sounds | 
              | ralGDS use ral Guanine Nucleotide Exchange Factor | 
              | Raloxifene | 
              | Ralstonia | 
              | Ralstonia eutropha use Cupriavidus necator | 
              | Ralstonia pickettii | 
              | Ralstonia solanacearum | 
              | Raman Spectroscopy use Spectrum Analysis, Raman | 
              | Ramie use Boehmeria | 
              | Ramipril | 
              | Ramps use Architectural Accessibility | 
              | Ramsay Hunt Auricular Syndrome use Herpes Zoster Oticus | 
              | Ramsay Hunt Cerebellar Syndrome use Myoclonic Cerebellar Dyssynergia | 
              | Ramsay Hunt Paralysis Syndrome use Parkinsonian Disorders | 
              | ran GTP-Binding Protein | 
              | ran Protein use ran GTP-Binding Protein | 
              | Rana use Ranidae | 
              | Rana bufo use Bufo rana | 
              | Rana catesbeiana | 
              | Rana esculenta | 
              | Rana pipiens | 
              | Rana ridibunda | 
              | Rana temporaria | 
              | Ranavirus | 
              | Randia use Rubiaceae | 
              | Random Allocation | 
              | Random Amplified Polymorphic DNA Technique | 
              | Random and Systematic Sampling | 
              | Random Peptide Library use Peptide Library | 
              | Randomization use Random Allocation | 
              | Randomized Controlled Clinical Trial use Randomized Controlled Trial | 
              | Randomized Controlled Trial | 
              | Randomized Controlled Trials as Topic | 
              | Range of Motion, Articular | 
              | Ranid herpesvirus 1 use Herpesvirus 1, Ranid | 
              | Ranidae | 
              | Ranitidine | 
              | RANK Ligand | 
              | Rank-Sum Tests use Statistics, Nonparametric | 
              | RANTES use Chemokine CCL5 | 
              | Ranula | 
              | Ranunculaceae | 
              | Ranunculus | 
              | Ranunculus acris | 
              | Ranunculus bulbosus | 
              | Ranunculus ficaria | 
              | Ranunculus flammula | 
              | Ranunculus glacialis | 
              | Ranunculus repens | 
              | Ranunculus sceleratus | 
              | Ranvier's Nodes | 
              | rap GTP-Binding Proteins | 
              | rap1 GTP-Binding Proteins | 
              | rap1A GTP-Binding Protein use rap1 GTP-Binding Proteins | 
              | Rapadura | 
              | Rapamycin use Sirolimus | 
              | Rapamycin Binding Proteins use Tacrolimus Binding Proteins | 
              | Rapanea use Myrsinaceae | 
              | RAPD Technique use Random Amplified Polymorphic DNA Technique | 
              | RAPD-PCR use Random Amplified Polymorphic DNA Technique | 
              | Rape | 
              | Rapeseed use Brassica rapa | 
              | Raphanistrum arvense | 
              | Raphanus | 
              | Raphanus sativus | 
              | Raphe Nuclei | 
              | Rapid Evaluation | 
              | Rapid Eye Movement Sleep Behavior Disorder use REM Sleep Behavior Disorder | 
              | Rapid Eye Movement Sleep Parasomnias use REM Sleep Parasomnias | 
              | Rapid Eye Movements use Sleep, REM | 
              | Rapid Filters | 
              | Rapid Filtration | 
              | Rapid Mix | 
              | Rappel Descent | 
              | Raptors | 
              | Rare Books | 
              | Rare Diseases | 
              | Rare Earth Metals use Metals, Rare Earth | 
              | Rare Gases use Noble Gases | 
              | RAS use Simplified Sewerage | 
              | ras Genes use Genes, ras | 
              | ras GTPase-Activating Proteins | 
              | ras Guanine Nucleotide Exchange Factors | 
              | ras Oncogene Protein p21 use Oncogene Protein p21(ras) | 
              | ras Proteins | 
              | ras Proto-Oncogene Protein p21 use Proto-Oncogene Proteins p21(ras) | 
              | ras-GAPs use ras GTPase-Activating Proteins | 
              | ras-GRF1 | 
              | ras-Related GTPases use Monomeric GTP-Binding Proteins | 
              | ras-Related rap Proteins use rap GTP-Binding Proteins | 
              | rasGEFs use ras Guanine Nucleotide Exchange Factors | 
              | Rash use Exanthema | 
              | Rasmussen Syndrome use Encephalitis | 
              | Rat coronavirus use Coronavirus, Rat | 
              | Rat Cytomegalovirus use Muromegalovirus | 
              | Rat encephalomyelitis virus use Theilovirus | 
              | Rat Kangaroo use Potoroidae | 
              | Rat Nematode use Nippostrongylus | 
              | Rat Tapeworm use Hymenolepis diminuta | 
              | Rat virus use Parvovirus | 
              | Rat-Bite Fever | 
              | Ratanhia peruviana | 
              | Ratany use Krameriaceae | 
              | Rate Setting and Review | 
              | Rates, Ratios and Proportions | 
              | Rathke Cleft Cysts use Central Nervous System Cysts | 
              | Rathke Pouch Tumor use Craniopharyngioma | 
              | Ratibida | 
              | Ratification | 
              | Rational-Emotive Psychotherapy use Psychotherapy, Rational-Emotive | 
              | Rationalization | 
              | Rationing, Health Care use Health Care Rationing | 
              | Ratites use Palaeognathae | 
              | Rats | 
              | Rats, Athymic use Rats, Nude | 
              | Rats, Bandicoot use Murinae | 
              | Rats, Brattleboro | 
              | Rats, Cotton use Sigmodontinae | 
              | Rats, Gunn | 
              | Rats, Hairless | 
              | Rats, Holtzman use Rats, Sprague-Dawley | 
              | Rats, Inbred A x C 9935 Irish use Rats, Inbred ACI | 
              | Rats, Inbred ACI | 
              | Rats, Inbred BB | 
              | Rats, Inbred BN | 
              | Rats, Inbred Brown Norway use Rats, Inbred BN | 
              | Rats, Inbred BUF | 
              | Rats, Inbred Buffalo use Rats, Inbred BUF | 
              | Rats, Inbred CDF use Rats, Inbred F344 | 
              | Rats, Inbred Dahl | 
              | Rats, Inbred F344 | 
              | Rats, Inbred Fischer 344 use Rats, Inbred F344 | 
              | Rats, Inbred LEC | 
              | Rats, Inbred Lew | 
              | Rats, Inbred Lewis use Rats, Inbred Lew | 
              | Rats, Inbred Long-Evans Cinnamon use Rats, Inbred LEC | 
              | Rats, Inbred OLETF | 
              | Rats, Inbred SHR | 
              | Rats, Inbred Strains | 
              | Rats, Inbred WF | 
              | Rats, Inbred Wistar Furth use Rats, Inbred WF | 
              | Rats, Inbred WKY | 
              | Rats, Kangaroo use Dipodomys | 
              | Rats, Long-Evans | 
              | Rats, Mutant Strains | 
              | Rats, Nude | 
              | Rats, Rice use Sigmodontinae | 
              | Rats, Sand use Gerbillinae | 
              | Rats, Spontaneously Hypertensive use Rats, Inbred SHR | 
              | Rats, Sprague-Dawley | 
              | Rats, Transgenic | 
              | Rats, Wistar | 
              | Rats, Wistar Furth use Rats, Inbred WF | 
              | Rats, Wistar Kyoto use Rats, Inbred WKY | 
              | Rats, Zucker | 
              | Rattlepod Chipilin use Crotalaria | 
              | Rattlesnake use Crotalus | 
              | Rattlesnake Venoms use Crotalid Venoms | 
              | Rattus use Rats | 
              | Raulinoa use Rutaceae | 
              | Rauscher Spleen Focus-Forming Virus use Spleen Focus-Forming Viruses | 
              | Rauscher Virus | 
              | Rauwolfia | 
              | Rauwolfia serpentina | 
              | Rauwolscine use Yohimbine | 
              | Ravens use Crows | 
              | Raw Effluents | 
              | Raw Water | 
              | Raynaud Disease | 
              | Rays (Fish) use Skates (Fish) | 
              | Razoxane | 
              | Rb Genes use Genes, Retinoblastoma | 
              | Rb Protein use Retinoblastoma Protein | 
              | RDA use Nutrition Policy | 
              | Reactants, Acute-Phase use Acute-Phase Proteins | 
              | Reaction Time | 
              | Reaction, Acute-Phase use Acute-Phase Reaction | 
              | Reactive Attachment Disorder | 
              | Reactive Disorders use Adjustment Disorders | 
              | Reactive Hemophagocytic Syndrome use Lymphohistiocytosis, Hemophagocytic | 
              | Reactive Inhibition | 
              | Reactive Nitrogen Species | 
              | Reactive Oxygen Species | 
              | Reactive Site use Catalytic Domain | 
              | Reactivity-Stability | 
              | Readability use Comprehension | 
              | Readiness Potential use Contingent Negative Variation | 
              | Reading | 
              | Reading Disability, Acquired use Dyslexia, Acquired | 
              | Reading Disability, Developmental use Dyslexia | 
              | Reading Disorder use Dyslexia | 
              | Reading Disorder, Developmental use Dyslexia | 
              | Reading Frames | 
              | Reagent Kits, Diagnostic | 
              | Reagent Strips | 
              | Reagent Substances, Products and Materials | 
              | Reagents use Indicators and Reagents | 
              | Reagins | 
              | Real-Time Systems use Computer Systems | 
              | Reality Testing | 
              | Reality Therapy | 
              | Reassortant Viruses | 
              | Reaven Syndrome X use Metabolic Syndrome X | 
              | Rec A Protein use Rec A Recombinases | 
              | Rec A Recombinases | 
              | Recall use Mental Recall | 
              | Receiver Operating Characteristic use ROC Curve | 
              | Receptive Aphasia use Aphasia, Wernicke | 
              | Receptor Activator of Nuclear Factor-kappa B | 
              | Receptor Aggregation | 
              | Receptor Cross-Talk | 
              | Receptor Down-Regulation use Down-Regulation | 
              | Receptor Protein-Tyrosine Kinases | 
              | Receptor Up-Regulation use Up-Regulation | 
              | Receptor, Adenosine A1 | 
              | Receptor, Adenosine A2A | 
              | Receptor, Adenosine A2B | 
              | Receptor, Adenosine A3 | 
              | Receptor, alpha-2 Macroglobulin use LDL-Receptor Related Protein 1 | 
              | Receptor, Anaphylatoxin C5a | 
              | Receptor, Angiotensin II Type 2 use Receptor, Angiotensin, Type 2 | 
              | Receptor, Angiotensin, Type 1 | 
              | Receptor, Angiotensin, Type 1a use Receptor, Angiotensin, Type 1 | 
              | Receptor, Angiotensin, Type 1b use Receptor, Angiotensin, Type 1 | 
              | Receptor, Angiotensin, Type 2 | 
              | Receptor, Apolipoprotein E use LDL-Receptor Related Protein 1 | 
              | Receptor, Bradykinin B1 | 
              | Receptor, Bradykinin B2 | 
              | Receptor, Cannabinoid, CB1 | 
              | Receptor, Cannabinoid, CB2 | 
              | Receptor, Cholecystokinin A | 
              | Receptor, Cholecystokinin B | 
              | Receptor, Ciliary Neurotrophic Factor | 
              | Receptor, Complement 3 use Macrophage-1 Antigen | 
              | Receptor, Complement 5a use Receptor, Anaphylatoxin C5a | 
              | Receptor, CSF-1 use Receptor, Macrophage Colony-Stimulating Factor | 
              | Receptor, EGF use Receptor, Epidermal Growth Factor | 
              | Receptor, Endothelin A | 
              | Receptor, Endothelin B | 
              | Receptor, Endothelin B, Type 2 use Receptor, Endothelin B | 
              | Receptor, EphA1 | 
              | Receptor, EphA2 | 
              | Receptor, EphA3 | 
              | Receptor, EphA4 | 
              | Receptor, EphA5 | 
              | Receptor, EphA6 | 
              | Receptor, EphA7 | 
              | Receptor, EphA8 | 
              | Receptor, EphB1 | 
              | Receptor, EphB2 | 
              | Receptor, EphB3 | 
              | Receptor, EphB4 | 
              | Receptor, EphB5 | 
              | Receptor, EphB6 | 
              | Receptor, Epidermal Growth Factor | 
              | Receptor, erbB-2 | 
              | Receptor, erbB-3 | 
              | Receptor, Fibroblast Growth Factor, Type 1 | 
              | Receptor, Fibroblast Growth Factor, Type 2 | 
              | Receptor, Fibroblast Growth Factor, Type 3 | 
              | Receptor, Fibroblast Growth Factor, Type 4 | 
              | Receptor, Fibroblast Growth Factor, Type 5 | 
              | Receptor, Galanin, Type 1 | 
              | Receptor, Galanin, Type 2 | 
              | Receptor, Galanin, Type 3 | 
              | Receptor, IGF Type 1 | 
              | Receptor, IGF Type 2 | 
              | Receptor, IGF-I use Receptor, IGF Type 1 | 
              | Receptor, IGF-II use Receptor, IGF Type 2 | 
              | Receptor, Insulin | 
              | Receptor, Insulin-Like Growth Factor I use Receptor, IGF Type 1 | 
              | Receptor, Insulin-Like Growth Factor II use Receptor, IGF Type 2 | 
              | Receptor, Insulin-Like Growth Factor Type 1 use Receptor, IGF Type 1 | 
              | Receptor, Insulin-Like Growth Factor Type 2 use Receptor, IGF Type 2 | 
              | Receptor, Interferon alpha-beta | 
              | Receptor, Interleukin-13 alpha2 use Interleukin-13 Receptor alpha2 Subunit | 
              | Receptor, Interleukin-4, 13 use Receptors, Interleukin-4, Type II | 
              | Receptor, Macrophage Colony-Stimulating Factor | 
              | Receptor, Mannose-6-Phosphate use Receptor, IGF Type 2 | 
              | Receptor, Melanocortin, Type 1 | 
              | Receptor, Melanocortin, Type 2 | 
              | Receptor, Melanocortin, Type 3 | 
              | Receptor, Melanocortin, Type 4 | 
              | Receptor, Melatonin, MT1 | 
              | Receptor, Melatonin, MT2 | 
              | Receptor, Muscarinic M1 | 
              | Receptor, Muscarinic M2 | 
              | Receptor, Muscarinic M3 | 
              | Receptor, Muscarinic M4 | 
              | Receptor, Muscarinic M5 | 
              | Receptor, Nerve Growth Factor | 
              | Receptor, neu use Receptor, erbB-2 | 
              | Receptor, Neurotrophic Tyrosine Kinase Type 1 use Receptor, trkA | 
              | Receptor, Neurotrophic Tyrosine-Kinase Type 2 use Receptor, trkB | 
              | Receptor, Neurotrophic-Tyrosine-Kinase Type 3 use Receptor, trkC | 
              | Receptor, Notch1 | 
              | Receptor, Notch2 | 
              | Receptor, PAR-1 | 
              | Receptor, PAR-2 | 
              | Receptor, Parathyroid Hormone, Type 1 | 
              | Receptor, Parathyroid Hormone, Type 2 | 
              | Receptor, PDGF alpha use Receptor, Platelet-Derived Growth Factor alpha | 
              | Receptor, PDGF beta use Receptor, Platelet-Derived Growth Factor beta | 
              | Receptor, Platelet-Derived Growth Factor alpha | 
              | Receptor, Platelet-Derived Growth Factor beta | 
              | Receptor, Serotonin, 5-HT1A | 
              | Receptor, Serotonin, 5-HT1B | 
              | Receptor, Serotonin, 5-HT1D | 
              | Receptor, Serotonin, 5-HT2A | 
              | Receptor, Serotonin, 5-HT2B | 
              | Receptor, Serotonin, 5-HT2C | 
              | Receptor, Stem Cell Factor use Proto-Oncogene Proteins c-kit | 
              | Receptor, TGF-alpha use Receptor, Epidermal Growth Factor | 
              | Receptor, TIE-1 | 
              | Receptor, TIE-2 | 
              | Receptor, Transforming-Growth Factor alpha use Receptor, Epidermal Growth Factor | 
              | Receptor, trkA | 
              | Receptor, trkB | 
              | Receptor, trkC | 
              | Receptor, Urogastrone use Receptor, Epidermal Growth Factor | 
              | Receptor-CD3 Complex, Antigen, T-Cell | 
              | Receptor-Interacting Protein Serine-Threonine Kinase 2 | 
              | Receptor-Interacting Protein Serine-Threonine Kinases | 
              | Receptor-Like Protein Tyrosine Phosphatases | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 1 | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 2 | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 2A use Receptor-Like Protein Tyrosine Phosphatases, Class 2 | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 2B use Receptor-Like Protein Tyrosine Phosphatases, Class 2 | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 3 | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 4 | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 5 | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 6 use Receptor-Like Protein Tyrosine Phosphatases, Class 1 | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 7 | 
              | Receptor-Like Protein Tyrosine Phosphatases, Class 8 | 
              | Receptor-Mediated Signal Transduction use Signal Transduction | 
              | Receptor-Regulated Smad Proteins use Smad Proteins, Receptor-Regulated | 
              | Receptors alpha, Thyroid Hormone use Thyroid Hormone Receptors alpha | 
              | Receptors beta, Thyroid Hormone use Thyroid Hormone Receptors beta | 
              | Receptors, Acetylcholine use Receptors, Cholinergic | 
              | Receptors, ACTH use Receptors, Corticotropin | 
              | Receptors, Adenosine use Receptors, Purinergic P1 | 
              | Receptors, Adenosine A2 | 
              | Receptors, Adipokine | 
              | Receptors, Adiponectin | 
              | Receptors, ADP use Receptors, Purinergic P2 | 
              | Receptors, Adrenergic | 
              | Receptors, Adrenergic, alpha | 
              | Receptors, Adrenergic, alpha-1 | 
              | Receptors, Adrenergic, alpha-2 | 
              | Receptors, Adrenergic, beta | 
              | Receptors, Adrenergic, beta-1 | 
              | Receptors, Adrenergic, beta-2 | 
              | Receptors, Adrenergic, beta-3 | 
              | Receptors, Adrenocorticotropic Hormone use Receptors, Corticotropin | 
              | Receptors, AH use Receptors, Aryl Hydrocarbon | 
              | Receptors, Albumin | 
              | Receptors, Aldosterone | 
              | Receptors, alpha-1 Adrenergic use Receptors, Adrenergic, alpha-1 | 
              | Receptors, alpha-2 Adrenergic use Receptors, Adrenergic, alpha-2 | 
              | Receptors, alpha-Adrenergic use Receptors, Adrenergic, alpha | 
              | Receptors, Amino Acid | 
              | Receptors, AMPA | 
              | Receptors, Androgen | 
              | Receptors, ANF use Receptors, Atrial Natriuretic Factor | 
              | Receptors, Angiotensin | 
              | Receptors, Antigen | 
              | Receptors, Antigen, B-Cell | 
              | Receptors, Antigen, T-Cell | 
              | Receptors, Antigen, T-Cell, alpha-beta | 
              | Receptors, Antigen, T-Cell, gamma-delta | 
              | Receptors, Aryl Hydrocarbon | 
              | Receptors, ATP use Receptors, Purinergic P2 | 
              | Receptors, Atrial Natriuretic Factor | 
              | Receptors, Atriopeptin use Receptors, Atrial Natriuretic Factor | 
              | Receptors, Benzodiazepine use Receptors, GABA-A | 
              | Receptors, Benzodiazepine-GABA use Receptors, GABA-A | 
              | Receptors, beta-1 Adrenergic use Receptors, Adrenergic, beta-1 | 
              | Receptors, beta-2 Adrenergic use Receptors, Adrenergic, beta-2 | 
              | Receptors, beta-3 Adrenergic use Receptors, Adrenergic, beta-3 | 
              | Receptors, beta-Adrenergic use Receptors, Adrenergic, beta | 
              | Receptors, Biogenic Amine | 
              | Receptors, Bombesin | 
              | Receptors, Bradykinin | 
              | Receptors, C3b use Receptors, Complement 3b | 
              | Receptors, C3d use Receptors, Complement 3d | 
              | Receptors, Caerulein use Receptors, Cholecystokinin | 
              | Receptors, Calcitonin | 
              | Receptors, Calcitonin Gene-Related Peptide | 
              | Receptors, Calcitriol | 
              | Receptors, Calcium Channel Blocker use Calcium Channels | 
              | Receptors, Calcium-Sensing | 
              | Receptors, Cannabinoid | 
              | Receptors, Catecholamine | 
              | Receptors, CCK use Receptors, Cholecystokinin | 
              | Receptors, CCR | 
              | Receptors, CCR1 | 
              | Receptors, CCR10 | 
              | Receptors, CCR2 | 
              | Receptors, CCR3 | 
              | Receptors, CCR4 | 
              | Receptors, CCR5 | 
              | Receptors, CCR6 | 
              | Receptors, CCR7 | 
              | Receptors, CCR8 | 
              | Receptors, CD4 use Antigens, CD4 | 
              | Receptors, Cell Surface | 
              | Receptors, CGRP use Receptors, Calcitonin Gene-Related Peptide | 
              | Receptors, Chemokine | 
              | Receptors, Cholecystokinin | 
              | Receptors, Cholinergic | 
              | Receptors, Chorionic Gonadotropin use Receptors, LH | 
              | Receptors, Collagen | 
              | Receptors, Colony-Stimulating Factor | 
              | Receptors, Complement | 
              | Receptors, Complement 3b | 
              | Receptors, Complement 3d | 
              | Receptors, Concanavalin A | 
              | Receptors, Corticosteroid use Receptors, Steroid | 
              | Receptors, Corticotropin | 
              | Receptors, Corticotropin-Releasing Hormone | 
              | Receptors, CR1 use Receptors, Complement 3b | 
              | Receptors, CR2 use Receptors, Complement 3d | 
              | Receptors, CRH use Receptors, Corticotropin-Releasing Hormone | 
              | Receptors, CXCR | 
              | Receptors, CXCR1 use Receptors, Interleukin-8A | 
              | Receptors, CXCR2 use Receptors, Interleukin-8B | 
              | Receptors, CXCR3 | 
              | Receptors, CXCR4 | 
              | Receptors, CXCR5 | 
              | Receptors, Cyclic AMP | 
              | Receptors, Cytoadhesin | 
              | Receptors, Cytokine | 
              | Receptors, Cytoplasmic and Nuclear | 
              | Receptors, Death Domain | 
              | Receptors, delta use Receptors, Opioid, delta | 
              | Receptors, delta Opioid use Receptors, Opioid, delta | 
              | Receptors, Diazepam use Receptors, GABA-A | 
              | Receptors, Dihydropyridine use Calcium Channels, L-Type | 
              | Receptors, Diiodotyrosine use Receptors, Thyroid Hormone | 
              | Receptors, Dioxin use Receptors, Aryl Hydrocarbon | 
              | Receptors, Dopamine | 
              | Receptors, Dopamine D1 | 
              | Receptors, Dopamine D2 | 
              | Receptors, Dopamine D3 | 
              | Receptors, Dopamine D4 | 
              | Receptors, Dopamine D5 | 
              | Receptors, Drug | 
              | Receptors, Ectodysplasin | 
              | Receptors, Edar use Edar Receptor | 
              | Receptors, Eicosanoid | 
              | Receptors, Endogenous Substances use Receptors, Cell Surface | 
              | Receptors, Endorphin use Receptors, Opioid | 
              | Receptors, Endothelin | 
              | Receptors, Endothelium-Derived Vasoconstrictor Factor use Receptors, Endothelin | 
              | Receptors, Enkephalin use Receptors, Opioid | 
              | Receptors, Eph Family | 
              | Receptors, Epidermal Growth Factor-Urogastrone use Receptor, Epidermal Growth Factor | 
              | Receptors, Epinephrine use Receptors, Adrenergic | 
              | Receptors, Epoprostenol | 
              | Receptors, Erythropoietin | 
              | Receptors, Estradiol | 
              | Receptors, Estrogen | 
              | Receptors, Excitatory Amino Acid use Receptors, Glutamate | 
              | Receptors, Extracellular Matrix Glycoprotein use Receptors, Cytoadhesin | 
              | Receptors, fas use Antigens, CD95 | 
              | Receptors, Fc | 
              | Receptors, Fc epsilon use Receptors, IgE | 
              | Receptors, Fc gamma use Receptors, IgG | 
              | Receptors, FGF use Receptors, Fibroblast Growth Factor | 
              | Receptors, Fibrinogen | 
              | Receptors, Fibroblast Growth Factor | 
              | Receptors, Fibronectin | 
              | Receptors, Follicle-Stimulating Hormone use Receptors, FSH | 
              | Receptors, Formyl Peptide | 
              | Receptors, FSH | 
              | Receptors, G-Protein-Coupled | 
              | Receptors, GABA | 
              | Receptors, GABA-A | 
              | Receptors, GABA-B | 
              | Receptors, GABA-Benzodiazepine use Receptors, GABA-A | 
              | Receptors, Galanin | 
              | Receptors, gamma-Aminobutyric Acid use Receptors, GABA | 
              | Receptors, Gastrin use Receptor, Cholecystokinin B | 
              | Receptors, Gastrin-Releasing Peptide use Receptors, Bombesin | 
              | Receptors, Gastrointestinal Hormone | 
              | Receptors, Gastrointestinal Peptides use Receptors, Gastrointestinal Hormone | 
              | Receptors, Ghrelin | 
              | Receptors, Glucagon | 
              | Receptors, Glucocorticoid | 
              | Receptors, Glutamate | 
              | Receptors, Glutamate, Metabotropic use Receptors, Metabotropic Glutamate | 
              | Receptors, Glycine | 
              | Receptors, GnRH use Receptors, LHRH | 
              | Receptors, Gonadoliberin use Receptors, LHRH | 
              | Receptors, Gonadorelin use Receptors, LHRH | 
              | Receptors, Gonadotropin | 
              | Receptors, Granulocyte Colony-Stimulating Factor | 
              | Receptors, Granulocyte-Macrophage Colony-Stimulating Factor | 
              | Receptors, Growth Factor | 
              | Receptors, Growth Hormone use Receptors, Somatotropin | 
              | Receptors, Guanylate Cyclase-Coupled | 
              | Receptors, Hematopoietic Growth Factors use Receptors, Colony-Stimulating Factor | 
              | Receptors, Histamine | 
              | Receptors, Histamine H1 | 
              | Receptors, Histamine H2 | 
              | Receptors, Histamine H3 | 
              | Receptors, HIV | 
              | Receptors, Human Chorionic Gonadotropin use Receptors, LH | 
              | Receptors, Hyaluronan use Antigens, CD44 | 
              | Receptors, Hypothalamic Release-Inhibiting Hormones use Receptors, Pituitary Hormone-Regulating Hormone | 
              | Receptors, Hypothalamic Releasing Hormones use Receptors, Pituitary Hormone-Regulating Hormone | 
              | Receptors, IgE | 
              | Receptors, IgG | 
              | Receptors, IL-1 use Receptors, Interleukin-1 | 
              | Receptors, IL-10 use Receptors, Interleukin-10 | 
              | Receptors, IL-2 use Receptors, Interleukin-2 | 
              | Receptors, IL-3 use Receptors, Interleukin-3 | 
              | Receptors, IL-4 use Receptors, Interleukin-4 | 
              | Receptors, IL-6 use Receptors, Interleukin-6 | 
              | Receptors, IL-7 use Receptors, Interleukin-7 | 
              | Receptors, IL-9 use Receptors, Interleukin-9 | 
              | Receptors, Imidazoline-Guanidinium use Imidazoline Receptors | 
              | Receptors, Immunologic | 
              | Receptors, Insulin-Like Growth Factors use Receptors, Somatomedin | 
              | Receptors, Interferon | 
              | Receptors, Interleukin | 
              | Receptors, Interleukin Common gamma Chain use Interleukin Receptor Common gamma Subunit | 
              | Receptors, Interleukin-1 | 
              | Receptors, Interleukin-1 Type I | 
              | Receptors, Interleukin-1 Type II | 
              | Receptors, Interleukin-10 | 
              | Receptors, Interleukin-11 | 
              | Receptors, Interleukin-12 | 
              | Receptors, Interleukin-13 | 
              | Receptors, Interleukin-15 | 
              | Receptors, Interleukin-16 | 
              | Receptors, Interleukin-17 | 
              | Receptors, Interleukin-18 | 
              | Receptors, Interleukin-2 | 
              | Receptors, Interleukin-21 | 
              | Receptors, Interleukin-3 | 
              | Receptors, Interleukin-4 | 
              | Receptors, Interleukin-4, 13 use Receptors, Interleukin-4, Type II | 
              | Receptors, Interleukin-4, Type I | 
              | Receptors, Interleukin-4, Type II | 
              | Receptors, Interleukin-5 | 
              | Receptors, Interleukin-6 | 
              | Receptors, Interleukin-7 | 
              | Receptors, Interleukin-8 | 
              | Receptors, Interleukin-8A | 
              | Receptors, Interleukin-8B | 
              | Receptors, Interleukin-9 | 
              | Receptors, Interstitial Cell-Stimulating Hormone use Receptors, LH | 
              | Receptors, Invertebrate Peptide | 
              | Receptors, Kainate use Receptors, Kainic Acid | 
              | Receptors, Kainic Acid | 
              | Receptors, kappa use Receptors, Opioid, kappa | 
              | Receptors, kappa Opioid use Receptors, Opioid, kappa | 
              | Receptors, KIR | 
              | Receptors, KIR2DL1 | 
              | Receptors, KIR2DL2 | 
              | Receptors, KIR2DL3 | 
              | Receptors, KIR2DL4 | 
              | Receptors, KIR2DL5 | 
              | Receptors, KIR3DL1 | 
              | Receptors, KIR3DL2 | 
              | Receptors, KIR3DS1 | 
              | Receptors, Laminin | 
              | Receptors, LDL | 
              | Receptors, Lectin use Receptors, Mitogen | 
              | Receptors, Leptin | 
              | Receptors, Leukemia Inhibitory Factor use Receptors, OSM-LIF | 
              | Receptors, Leukocyte-Adhesion | 
              | Receptors, Leukotriene | 
              | Receptors, Leukotriene B4 | 
              | Receptors, LH | 
              | Receptors, LHRH | 
              | Receptors, Lipopolysaccharide use Antigens, CD14 | 
              | Receptors, Lipoprotein | 
              | Receptors, Lipoxin | 
              | Receptors, Low Density Lipoprotein use Receptors, LDL | 
              | Receptors, Luliberin use Receptors, LHRH | 
              | Receptors, Luteinizing Hormone use Receptors, LH | 
              | Receptors, Lymphocyte Homing | 
              | Receptors, Lysophosphatidic Acid | 
              | Receptors, Lysophospholipid | 
              | Receptors, Lysosphingolipid | 
              | Receptors, Mating Factor | 
              | Receptors, Melanocortin | 
              | Receptors, Melatonin | 
              | Receptors, Menotropin use Receptors, Gonadotropin | 
              | Receptors, Metabotropic Glutamate | 
              | Receptors, Mineralocorticoid | 
              | Receptors, Mitogen | 
              | Receptors, Morphine use Receptors, Opioid, mu | 
              | Receptors, mu use Receptors, Opioid, mu | 
              | Receptors, mu Opioid use Receptors, Opioid, mu | 
              | Receptors, Muscarinic | 
              | Receptors, Muscarinic M4 use Receptor, Muscarinic M4 | 
              | Receptors, Muscimol use Receptors, GABA-A | 
              | Receptors, N-Acetylglucosamine | 
              | Receptors, N-Methyl-D-Aspartate | 
              | Receptors, Narcotic use Receptors, Opioid | 
              | Receptors, Natural Cytotoxicity Triggering | 
              | Receptors, Natural Killer Cell | 
              | Receptors, Nerve Growth Factor | 
              | Receptors, Neural use Sensory Receptor Cells | 
              | Receptors, Neurohumor use Receptors, Neurotransmitter | 
              | Receptors, Neurokinin-1 | 
              | Receptors, Neurokinin-2 | 
              | Receptors, Neurokinin-3 | 
              | Receptors, Neuromedin B use Receptors, Bombesin | 
              | Receptors, Neuropeptide | 
              | Receptors, Neuropeptide Y | 
              | Receptors, Neurotensin | 
              | Receptors, Neurotransmitter | 
              | Receptors, Neurotrophin use Receptors, Nerve Growth Factor | 
              | Receptors, NGF use Receptors, Nerve Growth Factor | 
              | Receptors, Nicotinic | 
              | Receptors, NK Cell Lectin-Like | 
              | Receptors, NK-2 use Receptors, Neurokinin-2 | 
              | Receptors, NK-3 use Receptors, Neurokinin-3 | 
              | Receptors, NMDA use Receptors, N-Methyl-D-Aspartate | 
              | Receptors, Norepinephrine use Receptors, Adrenergic | 
              | Receptors, Notch | 
              | Receptors, Odorant | 
              | Receptors, Oncostatin M | 
              | Receptors, Oncostatin M, Type II | 
              | Receptors, Opiate use Receptors, Opioid | 
              | Receptors, Opioid | 
              | Receptors, Opioid, delta | 
              | Receptors, Opioid, kappa | 
              | Receptors, Opioid, mu | 
              | Receptors, Opioid, sigma use Receptors, sigma | 
              | Receptors, OSM-LIF | 
              | Receptors, OX40 | 
              | Receptors, Oxidized LDL | 
              | Receptors, Oxytocin | 
              | Receptors, Pain use Nociceptors | 
              | Receptors, Pancreatic Hormone | 
              | Receptors, Pancreozymin use Receptors, Cholecystokinin | 
              | Receptors, Parathyroid Hormone | 
              | Receptors, Pattern Recognition | 
              | Receptors, PCP use Receptors, Phencyclidine | 
              | Receptors, PDGF use Receptors, Platelet-Derived Growth Factor | 
              | Receptors, Peptide | 
              | Receptors, Peptide, Invertebrate use Receptors, Invertebrate Peptide | 
              | Receptors, Phencyclidine | 
              | Receptors, Pheromone | 
              | Receptors, Phospholipase A2 | 
              | Receptors, Pituitary Adenylate Cyclase-Activating Peptide, Type II use Receptors, Vasoactive Intestinal Polypeptide, Type I | 
              | Receptors, Pituitary Adenylate Cyclase-Activating Peptide, Type III use Receptors, Vasoactive Intestinal Peptide, Type II | 
              | Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide | 
              | Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I | 
              | Receptors, Pituitary Hormone | 
              | Receptors, Pituitary Hormone Release Inhibiting Hormones use Receptors, Pituitary Hormone-Regulating Hormone | 
              | Receptors, Pituitary Hormone-Regulating Hormone | 
              | Receptors, Pituitary Hormone-Releasing Hormone use Receptors, Pituitary Hormone-Regulating Hormone | 
              | Receptors, Platelet-Derived Growth Factor | 
              | Receptors, Polymeric Immunoglobulin | 
              | Receptors, Presynaptic | 
              | Receptors, Progesterone | 
              | Receptors, Progestin use Receptors, Progesterone | 
              | Receptors, Prolactin | 
              | Receptors, Prostacyclin use Receptors, Epoprostenol | 
              | Receptors, Prostaglandin | 
              | Receptors, Prostaglandin E | 
              | Receptors, Prostaglandin H2 use Receptors, Thromboxane A2, Prostaglandin H2 | 
              | Receptors, Protein-Tyrosine Kinase use Receptor Protein-Tyrosine Kinases | 
              | Receptors, Proteinase-Activated | 
              | Receptors, Protirelin use Receptors, Thyrotropin-Releasing Hormone | 
              | Receptors, Pulmonary Stretch use Pulmonary Stretch Receptors | 
              | Receptors, Purinergic | 
              | Receptors, Purinergic P1 | 
              | Receptors, Purinergic P2 | 
              | Receptors, Retinoic Acid | 
              | Receptors, Scavenger | 
              | Receptors, Serotonin | 
              | Receptors, Serotonin, 5-HT1 | 
              | Receptors, Serotonin, 5-HT2 | 
              | Receptors, Serotonin, 5-HT3 | 
              | Receptors, Serotonin, 5-HT4 | 
              | Receptors, Serotonin, 5-HT4L use Receptors, Serotonin, 5-HT4 | 
              | Receptors, Serotonin, 5-HT4S use Receptors, Serotonin, 5-HT4 | 
              | Receptors, sigma | 
              | Receptors, sigma Opioid use Receptors, sigma | 
              | Receptors, Sincalide use Receptors, Cholecystokinin | 
              | Receptors, Somatomedin | 
              | Receptors, Somatostatin | 
              | Receptors, Somatotropin | 
              | Receptors, Somatotropin Release Inhibiting Hormone use Receptors, Somatostatin | 
              | Receptors, SRS-A use Receptors, Leukotriene | 
              | Receptors, Steroid | 
              | Receptors, Stretch use Mechanoreceptors | 
              | Receptors, Stretch, Arterial use Pressoreceptors | 
              | Receptors, Stretch, Muscle use Muscle Spindles | 
              | Receptors, Stretch, Pulmonary use Pulmonary Stretch Receptors | 
              | Receptors, Stretch, Vascular use Pressoreceptors | 
              | Receptors, Substance K use Receptors, Neurokinin-2 | 
              | Receptors, Substance P use Receptors, Neurokinin-1 | 
              | Receptors, Synaptic use Receptors, Neurotransmitter | 
              | Receptors, T-Cell Growth Factor use Receptors, Interleukin-2 | 
              | Receptors, Tachykinin | 
              | Receptors, TGF-beta use Receptors, Transforming Growth Factor beta | 
              | Receptors, Thrombin | 
              | Receptors, Thrombopoietin | 
              | Receptors, Thrombospondin use Antigens, CD36 | 
              | Receptors, Thromboxane | 
              | Receptors, Thromboxane A2 use Receptors, Thromboxane A2, Prostaglandin H2 | 
              | Receptors, Thromboxane A2, Prostaglandin H2 | 
              | Receptors, Thyroid Hormone | 
              | Receptors, Thyroid Stimulating Hormone use Receptors, Thyrotropin | 
              | Receptors, Thyroliberin use Receptors, Thyrotropin-Releasing Hormone | 
              | Receptors, Thyrotropin | 
              | Receptors, Thyrotropin-Releasing Hormone | 
              | Receptors, Thyroxine use Receptors, Thyroid Hormone | 
              | Receptors, TIE | 
              | Receptors, TNF-Related Apoptosis-Inducing Ligand | 
              | Receptors, Toll-Like use Toll-Like Receptors | 
              | Receptors, TRAIL use Receptors, TNF-Related Apoptosis-Inducing Ligand | 
              | Receptors, Transferrin | 
              | Receptors, Transforming Growth Factor beta | 
              | Receptors, TRH use Receptors, Thyrotropin-Releasing Hormone | 
              | Receptors, Triiodothyronine use Receptors, Thyroid Hormone | 
              | Receptors, Tryptamine use Receptors, Serotonin | 
              | Receptors, Tumor Necrosis Factor | 
              | Receptors, Tumor Necrosis Factor, Member 10 use Receptors, TNF-Related Apoptosis-Inducing Ligand | 
              | Receptors, Tumor Necrosis Factor, Member 10b use Receptors, TNF-Related Apoptosis-Inducing Ligand | 
              | Receptors, Tumor Necrosis Factor, Member 10c | 
              | Receptors, Tumor Necrosis Factor, Member 11a use Receptor Activator of Nuclear Factor-kappa B | 
              | Receptors, Tumor Necrosis Factor, Member 11b use Osteoprotegerin | 
              | Receptors, Tumor Necrosis Factor, Member 14 | 
              | Receptors, Tumor Necrosis Factor, Member 17 use B-Cell Maturation Antigen | 
              | Receptors, Tumor Necrosis Factor, Member 18 use Glucocorticoid-Induced TNFR-Related Protein | 
              | Receptors, Tumor Necrosis Factor, Member 1A use Receptors, Tumor Necrosis Factor, Type I | 
              | Receptors, Tumor Necrosis Factor, Member 1B use Receptors, Tumor Necrosis Factor, Type II | 
              | Receptors, Tumor Necrosis Factor, Member 25 | 
              | Receptors, Tumor Necrosis Factor, Member 4 use Receptors, OX40 | 
              | Receptors, Tumor Necrosis Factor, Member 6b | 
              | Receptors, Tumor Necrosis Factor, Type I | 
              | Receptors, Tumor Necrosis Factor, Type II | 
              | Receptors, TXA2-PGH2 use Receptors, Thromboxane A2, Prostaglandin H2 | 
              | Receptors, Urokinase Plasminogen Activator | 
              | Receptors, V1 use Receptors, Vasopressin | 
              | Receptors, V2 use Receptors, Vasopressin | 
              | Receptors, Vascular Endothelial Growth Factor | 
              | Receptors, Vasoactive Intestinal Peptide | 
              | Receptors, Vasoactive Intestinal Peptide, Type II | 
              | Receptors, Vasoactive Intestinal Polypeptide, Type I | 
              | Receptors, Vasopressin | 
              | Receptors, Very Late Antigen | 
              | Receptors, VIP use Receptors, Vasoactive Intestinal Peptide | 
              | Receptors, Virus | 
              | Receptors, Vitamin D use Receptors, Calcitriol | 
              | Receptors, Vitronectin | 
              | Receptors, VLA use Receptors, Very Late Antigen | 
              | Receptors, VLA-5 use Integrin alpha5beta1 | 
              | Receptosomes use Endosomes | 
              | Rechargable Batteries use Electric Batteries | 
              | Reciprocating Tachycardia use Tachycardia, Reciprocating | 
              | Recirculated Water use Water Recirculation | 
              | Recklinghausen Disease of Nerve use Neurofibromatosis 1 | 
              | Recklinghausen's Disease of Bone use Osteitis Fibrosa Cystica | 
              | Reclaimed Water use Water Recycling | 
              | Recognition (Psychology) | 
              | Recognized Refugee | 
              | Recombinant Colony-Stimulating Factors use Colony-Stimulating Factors, Recombinant | 
              | Recombinant DNA use DNA, Recombinant | 
              | Recombinant DNA Vaccines use Vaccines, DNA | 
              | Recombinant Erythropoietin use Erythropoietin, Recombinant | 
              | Recombinant Fusion Proteins | 
              | Recombinant G-CSF use Granulocyte Colony Stimulating Factor, Recombinant | 
              | Recombinant GM-CSF use Granulocyte Macrophage Colony-Stimulating Factors, Recombinant | 
              | Recombinant Granulocyte Colony Stimulating Factor use Granulocyte Colony Stimulating Factor, Recombinant | 
              | Recombinant Granulocyte-Macrophage Colony-Stimulating Factors use Granulocyte Macrophage Colony-Stimulating Factors, Recombinant | 
              | Recombinant Growth Hormone use Growth Hormone | 
              | Recombinant Interferon alfa-2a use Interferon Alfa-2a | 
              | Recombinant Interferon alfa-2b use Interferon Alfa-2b | 
              | Recombinant Interferon alfa-2c use Interferon Alfa-2c | 
              | Recombinant Interferon-gamma use Interferon-gamma, Recombinant | 
              | Recombinant Proteins | 
              | Recombinant-Methionyl Human Granulocyte Colony-Stimulating Factor use Filgrastim | 
              | Recombinases | 
              | Recombination, Genetic | 
              | Recombination, Interspecies use Gene Transfer, Horizontal | 
              | Recombination-Activating Genes-1 use Genes, RAG-1 | 
              | Recommended Dietary Allowances use Nutrition Policy | 
              | Reconstruction | 
              | Reconstructive Surgical Procedures | 
              | Reconstructive Surgical Procedures, Cosmetic use Reconstructive Surgical Procedures | 
              | Recontact use Duty to Recontact | 
              | Record Linkage, Medical use Medical Record Linkage | 
              | Records as Topic | 
              | Records Control use Forms and Records Control | 
              | Recoverin | 
              | Recovery use Recycling (Environmental Health) | 
              | Recovery of Function | 
              | Recovery Period, Anesthesia use Anesthesia Recovery Period | 
              | Recovery Room | 
              | Recovery Room Nursing use Postanesthesia Nursing | 
              | RecQ Helicases | 
              | Recreation | 
              | Recreation and Leisure Activities Centers use Centers of Connivance and Leisure | 
              | Recreation and Leisure Activities Centres use Centers of Connivance and Leisure | 
              | Recreational Drugs use Street Drugs | 
              | Recreational Water | 
              | Recreational Zones | 
              | Recrudescence use Recurrence | 
              | Recruitment Detection, Audiologic | 
              | Recruitment, Loudness use Hyperacusis | 
              | Recruitment, Neurophysiological | 
              | Rectal Cancer use Rectal Neoplasms | 
              | Rectal Diseases | 
              | Rectal Drug Administration use Administration, Rectal | 
              | Rectal Fistula | 
              | Rectal Gland use Salt Gland | 
              | Rectal Neoplasms | 
              | Rectal Prolapse | 
              | Rectal Suppositories use Suppositories | 
              | Rectal Surgery (Specialty) use Colorectal Surgery | 
              | Rectal Tumors use Rectal Neoplasms | 
              | Rectocele | 
              | Rectocolitis use Proctocolitis | 
              | Rectocolitis, Hemorrhagic use Proctocolitis | 
              | Rectocolitis, Ulcerative use Proctocolitis | 
              | Rectosigmoiditis use Proctocolitis | 
              | Rectovaginal Fistula | 
              | Rectum | 
              | Rectus Abdominis | 
              | Recurrence | 
              | Recurrent Laryngeal Nerve | 
              | Recycling use Conservation of Natural Resources | 
              | Recycling (Environmental Health) | 
              | Recycling, Equipment use Equipment Reuse | 
              | Red Blood Cell Count use Erythrocyte Count | 
              | Red Blood Cell Membrane Sialoglycoprotein use Glycophorin | 
              | Red Blood Cell Transfusion use Erythrocyte Transfusion | 
              | Red Blood Cells use Erythrocytes | 
              | Red Bryony use Bryonia dioica | 
              | Red Bugs use Trombiculidae | 
              | Red Cell Ghost use Erythrocyte Membrane | 
              | Red Cell Indices use Erythrocyte Indices | 
              | Red Cell Mass use Erythrocyte Volume | 
              | Red Cell Substitutes use Blood Substitutes | 
              | Red clover use Trifolium | 
              | Red Cross | 
              | Red Dye No. 2 use Amaranth Dye | 
              | Red Marrow use Bone Marrow | 
              | Red Monkey use Erythrocebus patas | 
              | Red Nucleus | 
              | Red Pepper use Capsicum | 
              | Red Quina use China officinalis | 
              | Red Sea use Indian Ocean | 
              | Red Tide use Dinoflagellida | 
              | Red-Cell Aplasia, Pure | 
              | Red-Sensitive Cone Opsins use Cone Opsins | 
              | Redistributive Justice use Equity in the Resource Allocation | 
              | Redox use Oxidation-Reduction | 
              | Reduced Gravity use Hypogravity | 
              | Reducing Agents | 
              | Reductants use Reducing Agents | 
              | Reductases use Oxidoreductases | 
              | Reduction Gear use Water and Sewerage System Accessories | 
              | Reductive Pentose Phosphate Cycle use Photosynthesis | 
              | Reduviidae | 
              | Redwood use Sequoia | 
              | Reed-Sternberg Cells | 
              | Reef | 
              | Reeler Mice use Mice, Neurologic Mutants | 
              | Refeeding Syndrome | 
              | Reference Books | 
              | Reference Books, Medical | 
              | Reference Centers use Information Services | 
              | Reference Drugs | 
              | Reference Ranges use Reference Values | 
              | Reference Standards | 
              | Reference Values | 
              | Referral and Consultation | 
              | Referred Pain use Pain, Referred | 
              | Refetoff Syndrome use Thyroid Hormone Resistance Syndrome | 
              | Refined Sugar use Sugar | 
              | Refining | 
              | Refitting use Remodeling | 
              | Reflex | 
              | Reflex Epilepsy use Epilepsy, Reflex | 
              | Reflex Epilepsy, Audiogenic use Epilepsy, Reflex | 
              | Reflex Epilepsy, Cursive (Running) use Epilepsy, Reflex | 
              | Reflex Epilepsy, Eating-Induced use Epilepsy, Reflex | 
              | Reflex Epilepsy, Musicogenic use Epilepsy, Reflex | 
              | Reflex Epilepsy, Photosensitive use Epilepsy, Reflex | 
              | Reflex Epilepsy, Reading use Epilepsy, Reflex | 
              | Reflex Sympathetic Dystrophy | 
              | Reflex Therapy use Reflexotherapy | 
              | Reflex, Abdominal | 
              | Reflex, Abnormal | 
              | Reflex, Acoustic | 
              | Reflex, Babinski | 
              | Reflex, Baroreceptor use Baroreflex | 
              | Reflex, Blink use Blinking | 
              | Reflex, Conditioned use Conditioning, Classical | 
              | Reflex, Corneal use Blinking | 
              | Reflex, Monosynaptic | 
              | Reflex, Oculocardiac | 
              | Reflex, Orbicularis Oculi use Blinking | 
              | Reflex, Pharyngeal use Gagging | 
              | Reflex, Psychogalvanic use Galvanic Skin Response | 
              | Reflex, Pupillary | 
              | Reflex, Stretch | 
              | Reflex, Tendon use Reflex, Stretch | 
              | Reflex, Vestibulo-Ocular | 
              | Reflexology use Massage | 
              | Reflexotherapy | 
              | Reforestation | 
              | Reformatories use Prisons | 
              | Refraction, Ocular | 
              | Refractive Errors | 
              | Refractive Index use Refractometry | 
              | Refractive Surgical Procedures | 
              | Refractometry | 
              | Refractory Anemia use Anemia, Refractory | 
              | Refractory Anemia with Excess of Blasts use Anemia, Refractory, with Excess of Blasts | 
              | Refractory Period, Electrophysiological | 
              | Refractory Period, Neurologic use Refractory Period, Electrophysiological | 
              | Refractory Period, Psychological | 
              | Refrigeration | 
              | Refsum Disease | 
              | Refsum Disease, Infantile | 
              | Refuge | 
              | Refugee Camps | 
              | Refugee Sur Place | 
              | Refugees | 
              | Refuges use Shelters | 
              | Refusal of Treatment use Treatment Refusal | 
              | Refusal to Participate | 
              | Refusal to Treat | 
              | Refuse Disposal | 
              | Refuse Dumps use Open Dumps | 
              | Regeneration | 
              | Regeneration, Periodontal Guided Tissue use Guided Tissue Regeneration, Periodontal | 
              | Regenerative Medicine | 
              | Regional Agencies | 
              | Regional Agreements | 
              | Regional Blood Flow | 
              | Regional Development | 
              | Regional Health Planning | 
              | Regional Hospital Planning use Hospital Planning | 
              | Regional Hospital Plannings use Hospital Planning | 
              | Regional Medical Programs | 
              | Regional Pacts use Regional Agreements | 
              | Regional Perfusion Antineoplastic Chemotherapy use Chemotherapy, Cancer, Regional Perfusion | 
              | Regional Plans | 
              | Regional Strategies | 
              | Regional Subsidence and Cracking | 
              | Registered Trademarks | 
              | Registrars, Hospital use Medical Staff, Hospital | 
              | Registries | 
              | Regression (Psychology) | 
              | Regression Analysis | 
              | Regression Diagnostics use Regression Analysis | 
              | Regulation of Gene Expression use Gene Expression Regulation | 
              | Regulation of Gene Expression, Archaeal use Gene Expression Regulation, Archaeal | 
              | Regulation of Gene Expression, Bacterial use Gene Expression Regulation, Bacterial | 
              | Regulation of Gene Expression, Developmental use Gene Expression Regulation, Developmental | 
              | Regulation of Gene Expression, Embryologic use Gene Expression Regulation, Developmental | 
              | Regulation of Gene Expression, Enzymologic use Gene Expression Regulation, Enzymologic | 
              | Regulation of Gene Expression, Fungal use Gene Expression Regulation, Fungal | 
              | Regulation of Gene Expression, Leukemic use Gene Expression Regulation, Leukemic | 
              | Regulation of Gene Expression, Neoplastic use Gene Expression Regulation, Neoplastic | 
              | Regulation of Gene Expression, Plant use Gene Expression Regulation, Plant | 
              | Regulation of Gene Expression, Viral use Gene Expression Regulation, Viral | 
              | Regulations | 
              | Regulations for Policy Organizations | 
              | Regulator Locus, araC use Genes, araC | 
              | Regulators of G-Protein Signaling Proteins use RGS Proteins | 
              | Regulators, G-Protein Signaling use GTP-Binding Protein Regulators | 
              | Regulatory Element, Transcriptional use Regulatory Elements, Transcriptional | 
              | Regulatory Elements, Transcriptional | 
              | Regulatory Regions, Nucleic Acid (Genetics) use Regulatory Sequences, Nucleic Acid | 
              | Regulatory Sequences, Nucleic Acid | 
              | Regulatory Sequences, Ribonucleic Acid | 
              | Regulatory T-Lymphocytes use T-Lymphocytes, Regulatory | 
              | Regulon | 
              | Regurgitation, Gastric use Gastroesophageal Reflux | 
              | Rehabilitation | 
              | Rehabilitation Centers | 
              | Rehabilitation Centers, Drug use Substance Abuse Treatment Centers | 
              | Rehabilitation Nursing | 
              | Rehabilitation of Hearing Impaired | 
              | Rehabilitation of Speech and Language Disorders | 
              | Rehabilitation Outcome use Treatment Outcome | 
              | Rehabilitation Services | 
              | Rehabilitation, Vocational | 
              | Rehmannia | 
              | Rehydration use Fluid Therapy | 
              | Rehydration Solutions | 
              | Rehydration, Oral use Fluid Therapy | 
              | Reichel's Syndrome use Chondromatosis, Synovial | 
              | Reiki use Therapeutic Touch | 
              | Reimbursement Mechanisms | 
              | Reimbursement, Disproportionate Share | 
              | Reimbursement, Fee-for-Service use Fee-for-Service Plans | 
              | Reimbursement, Health Insurance use Insurance, Health, Reimbursement | 
              | Reimbursement, Incentive | 
              | Reimbursement, Prospective use Prospective Payment System | 
              | Reimplantation use Replantation | 
              | Reimplantation, Tooth use Tooth Replantation | 
              | Reindeer | 
              | Reinerz Aqua | 
              | Reinforced Concrete | 
              | Reinforced Concrete Constructions use Reinforced Concrete | 
              | Reinforced Concrete Pipes | 
              | Reinforced Concrete Structures use Reinforced Concrete | 
              | Reinforced Concrete Tanks | 
              | Reinforcement (Psychology) | 
              | Reinforcement Schedule | 
              | Reinforcement, Social | 
              | Reinforcement, Verbal | 
              | Reinforcing Factors use Causality | 
              | Reishi | 
              | Rejection (Psychology) | 
              | Rejuvenation | 
              | rel Genes use Genes, rel | 
              | rel Oncogene Proteins use Oncogene Proteins v-rel | 
              | rel Proto-Oncogene Proteins use Proto-Oncogene Proteins c-rel | 
              | Relapse use Recurrence | 
              | Relapsing Fever | 
              | Relapsing Fever Ticks use Ornithodoros | 
              | Relapsing-Remitting Multiple Sclerosis use Multiple Sclerosis, Relapsing-Remitting | 
              | Relative Biological Effectiveness | 
              | Relative Risk use Risk | 
              | Relative Risk (Public Health) | 
              | Relative Value Scales | 
              | Relative-Value Schedules use Relative Value Scales | 
              | Relaxation | 
              | Relaxation Techniques use Relaxation Therapy | 
              | Relaxation Therapy | 
              | Relaxin | 
              | Released of Products use Product Release | 
              | Reliability and Validity use Reproducibility of Results | 
              | Relief Work | 
              | Relief, Assistance and Protection in Disasters | 
              | Religion | 
              | Religion and Medicine | 
              | Religion and Psychology | 
              | Religion and Science | 
              | Religion and Sex | 
              | Religious Beliefs use Religion | 
              | Religious Ethics use Religion | 
              | Religious Hospitals use Hospitals, Religious | 
              | Religious Philosophies | 
              | REM Sleep Behavior Disorder | 
              | REM Sleep Deprivation use Sleep Deprivation | 
              | REM Sleep Parasomnias | 
              | REM Sleep-Related Sinus Arrest use REM Sleep Parasomnias | 
              | Remantadine use Rimantadine | 
              | Remedial Teaching | 
              | Remediation | 
              | Reminder Systems | 
              | Reminyl use Galantamine | 
              | Remission Induction | 
              | Remission, Spontaneous | 
              | Remission, Spontaneous Neoplasm use Neoplasm Regression, Spontaneous | 
              | Remittent Fever use Malaria | 
              | Remodeling | 
              | Remote Consultation | 
              | Remote Operations (Robotics) use Robotics | 
              | Remote Sensors | 
              | Remote Sounding | 
              | Removal of Hulls Agent use Washing Agents | 
              | Removal of Hulls Agents use Washing Agents | 
              | Removers of Polish Nail, Cuticle and Nicotin Spot (Mechanical and Chemical Types) use Products for Nails and Cuticles | 
              | Remoxipride | 
              | Renal Agents | 
              | Renal Aminoacidurias | 
              | Renal Artery | 
              | Renal Artery Obstruction | 
              | Renal Artery Stenosis use Renal Artery Obstruction | 
              | Renal Blood Flow use Renal Circulation | 
              | Renal Blood Flow, Effective | 
              | Renal Calculi use Kidney Calculi | 
              | Renal Cancer use Kidney Neoplasms | 
              | Renal Circulation | 
              | Renal Cortical Necrosis use Kidney Cortex Necrosis | 
              | Renal Dialysis | 
              | Renal Dialysis Units, Hospital use Hemodialysis Units, Hospital | 
              | Renal Dialysis, Home use Hemodialysis, Home | 
              | Renal Disease, End-Stage use Kidney Failure, Chronic | 
              | Renal Failure use Kidney Failure | 
              | Renal Failure, Acute use Kidney Failure, Acute | 
              | Renal Failure, Chronic use Kidney Failure, Chronic | 
              | Renal Failure, End-Stage use Kidney Failure, Chronic | 
              | Renal Fanconi Syndrome use Fanconi Syndrome | 
              | Renal Insufficiency | 
              | Renal Insufficiency, Acute | 
              | Renal Insufficiency, Chronic | 
              | Renal Osteodystrophy | 
              | Renal Papillitis, Necrotizing use Kidney Papillary Necrosis | 
              | Renal Pelvis use Kidney Pelvis | 
              | Renal Plasma Flow | 
              | Renal Plasma Flow, Effective | 
              | Renal Replacement Therapy | 
              | Renal Rickets use Renal Osteodystrophy | 
              | Renal Transplantation use Kidney Transplantation | 
              | Renal Tubular Acidosis use Acidosis, Renal Tubular | 
              | Renal Tubular Acidosis, Type I use Acidosis, Renal Tubular | 
              | Renal Tubular Acidosis, Type II use Acidosis, Renal Tubular | 
              | Renal Tubular Acidosis, Type IV use Hypoaldosteronism | 
              | Renal Tubular Transport, Inborn Errors | 
              | Renal Veins | 
              | Renaturation, Protein use Protein Renaturation | 
              | Renealmia use Zingiberaceae | 
              | Renewable Energy use Non Conventional Energy | 
              | Renewable Resources | 
              | Renewal of Functioning Authorization | 
              | Renilla | 
              | Renin | 
              | Renin-Angiotensin System | 
              | Renin-Angiotensin-Aldosterone System use Renin-Angiotensin System | 
              | Renin-Substrate use Angiotensinogen | 
              | Rennin use Chymosin | 
              | Renography use Radioisotope Renography | 
              | Reoperation | 
              | Reoviridae | 
              | Reoviridae Infections | 
              | Reovirus 1 use Orthoreovirus, Mammalian | 
              | Reovirus 2 use Orthoreovirus, Mammalian | 
              | Reovirus 3 use Mammalian orthoreovirus 3 | 
              | Reovirus Infections use Reoviridae Infections | 
              | Reoviruses, Aquatic use Reoviridae | 
              | Repairing use Corrective Maintenance | 
              | Repatriation | 
              | Repeat Cesarean Section use Cesarean Section, Repeat | 
              | Repeat-Associated siRNA use RNA, Small Interfering | 
              | Reperfusion | 
              | Reperfusion Injury | 
              | Reperfusion Injury, Myocardial use Myocardial Reperfusion Injury | 
              | Reperfusion, Myocardial use Myocardial Reperfusion | 
              | Repertorial Additions | 
              | Repertorial Errors | 
              | Repertorial Structure | 
              | Repertorial Symptoms | 
              | Repertorization | 
              | Repertorization, Computed | 
              | Repertory | 
              | Repertory Techniques use Repertorization | 
              | Repertory, Barthel | 
              | Repertory, Boenninghausen | 
              | Repertory, Boericke | 
              | Repertory, Degrees | 
              | Repertory, Gentry | 
              | Repertory, Hering | 
              | Repertory, Kent | 
              | Repertory, Kent-Eizayaga | 
              | Repertory, Kishore | 
              | Repertory: Abdomen Section | 
              | Repertory: Back Section | 
              | Repertory: Bladder Section | 
              | Repertory: Chest Section | 
              | Repertory: Chill Section | 
              | Repertory: Cough Section | 
              | Repertory: Delusions Section | 
              | Repertory: Drinks and Foods Section | 
              | Repertory: Ear Section | 
              | Repertory: Expectoration Section | 
              | Repertory: External Throat Section | 
              | Repertory: Extremities Section | 
              | Repertory: Eye Section | 
              | Repertory: Face Section | 
              | Repertory: Female Genitalia Section | 
              | Repertory: Fever Section | 
              | Repertory: Generalities Section | 
              | Repertory: Head Section | 
              | Repertory: Hearing Section | 
              | Repertory: Internal Throat Section use Repertory: Throat Section | 
              | Repertory: Kidneys Section | 
              | Repertory: Larynx and Trachea Section | 
              | Repertory: Male Genitalia Section | 
              | Repertory: Mind Section | 
              | Repertory: Mouth Section | 
              | Repertory: Nails Section | 
              | Repertory: Nose Section | 
              | Repertory: Perspiration Section | 
              | Repertory: Prostate Section | 
              | Repertory: Rectum Section | 
              | Repertory: Respiration Section | 
              | Repertory: Skin Section | 
              | Repertory: Sleep Section | 
              | Repertory: Stomach Section | 
              | Repertory: Stool Section | 
              | Repertory: Taste Section | 
              | Repertory: Teeth Section | 
              | Repertory: Throat Section | 
              | Repertory: Urethra Section | 
              | Repertory: Urine Section | 
              | Repertory: Vertigo Section | 
              | Repertory: Vision Section | 
              | Repetition Strain Injury use Cumulative Trauma Disorders | 
              | Repetitive Region use Repetitive Sequences, Nucleic Acid | 
              | Repetitive Sequences, Amino Acid | 
              | Repetitive Sequences, Dispersed use Interspersed Repetitive Sequences | 
              | Repetitive Sequences, Interspersed use Interspersed Repetitive Sequences | 
              | Repetitive Sequences, Nucleic Acid | 
              | REPIDISCA use Pan American Center for Sanitary Engineering and Environmental Sciences | 
              | Replacement Therapy, Estrogen use Estrogen Replacement Therapy | 
              | Replacement Therapy, Hormone use Hormone Replacement Therapy | 
              | Replantation | 
              | Replantation, Tooth use Tooth Replantation | 
              | Replica Techniques | 
              | Replication Factor A use Replication Protein A | 
              | Replication Factor A Single-Stranded DNA-Binding Protein use Replication Protein A | 
              | Replication Factor C use Replication Protein C | 
              | Replication Origin | 
              | Replication Protein A | 
              | Replication Protein C | 
              | Replication Unit use Replicon | 
              | Replicative Senescence use Cell Aging | 
              | Replicon | 
              | Reporter Genes use Genes, Reporter | 
              | Repressed Memory use Repression | 
              | Repression | 
              | Repression-Sensitization | 
              | Repression-Sensitization Scales use Repression-Sensitization | 
              | Repressor Molecules use Repressor Proteins | 
              | Repressor Proteins | 
              | Reproducibility of Results | 
              | Reproduction | 
              | Reproduction, Asexual | 
              | Reproductive and Urinary Physiological Phenomena | 
              | Reproductive and Urinary Physiology use Reproductive and Urinary Physiological Phenomena | 
              | Reproductive and Urinary Physiology Phenomena use Reproductive and Urinary Physiological Phenomena | 
              | Reproductive Behavior | 
              | Reproductive Control Agents | 
              | Reproductive Health Services | 
              | Reproductive History | 
              | Reproductive Medicine | 
              | Reproductive Physiological Concepts use Reproductive Physiological Phenomena | 
              | Reproductive Physiological Phenomena | 
              | Reproductive Physiological Processes | 
              | Reproductive Rights | 
              | Reproductive Sterilization use Sterilization, Reproductive | 
              | Reproductive Techniques | 
              | Reproductive Techniques, Assisted | 
              | Reproductive Technology use Reproductive Techniques | 
              | Reproductive Technology, Assisted use Reproductive Techniques, Assisted | 
              | Reptilase Time use Thrombin Time | 
              | Reptiles | 
              | Reptilia use Reptiles | 
              | Reptilian Proteins | 
              | Republic of Burundi use Burundi | 
              | Republic of Cameron use Cameroon | 
              | Republic of China use Taiwan | 
              | Republic of South Africa use South Africa | 
              | Republic of the Congo use Congo | 
              | Request for Disaster Assistance | 
              | Request for Proposal use Competitive Bidding | 
              | Rescue in Confined Spaces | 
              | Rescue Personnel | 
              | Rescue Work | 
              | Rescue Workers use Rescue Personnel | 
              | Research | 
              | Research and Development Project Indicators | 
              | Research and Development Projects | 
              | Research and New Techniques | 
              | Research Design | 
              | Research Embryo Creation | 
              | Research Ethics use Ethics, Research | 
              | Research Expenditures | 
              | Research Financing | 
              | Research Financing Systems | 
              | Research Groups | 
              | Research in Health Services | 
              | Research Institutes use Academies and Institutes | 
              | Research Misconduct use Scientific Misconduct | 
              | Research on Health Personnel use Health Manpower | 
              | Research Personnel | 
              | Research Policy Evaluation | 
              | Research Priorities use Research | 
              | Research Promotion | 
              | Research Protocols, Clinical use Clinical Protocols | 
              | Research Reports | 
              | Research Subject Recruitment use Patient Selection | 
              | Research Subjects | 
              | Research Support as Topic | 
              | Research Support, N.I.H., Extramural | 
              | Research Support, N.I.H., Intramural | 
              | Research Support, Non-U.S. Gov't | 
              | Research Support, U.S. Gov't, Non-P.H.S. | 
              | Research Support, U.S. Gov't, P.H.S. | 
              | Research, Clinical Nursing use Clinical Nursing Research | 
              | Research, Dental use Dental Research | 
              | Research, Health Services use Health Services Research | 
              | Research, Nursing use Nursing Research | 
              | Research, Nursing Administration use Nursing Administration Research | 
              | Research, Nursing Education use Nursing Education Research | 
              | Research, Nursing Evaluation use Nursing Evaluation Research | 
              | Research, Nursing Methodology use Nursing Methodology Research | 
              | Researcher Exchange | 
              | Researcher Exchange Policy | 
              | Researcher Performance Evaluation Systems | 
              | Researcher-Subject Relations | 
              | Researchers use Research Personnel | 
              | Reseda use Resedaceae | 
              | Resedaceae | 
              | Reserpine | 
              | Reserpinum | 
              | Reservoir Routing use Flood Routing | 
              | Reservoirs | 
              | Residence Characteristics | 
              | Residence Time | 
              | Residency, Dental use Internship and Residency | 
              | Residency, Medical use Internship and Residency | 
              | Residency, Nonmedical use Internship, Nonmedical | 
              | Resident Population | 
              | Residential Facilities | 
              | Residential Mobility | 
              | Residential Treatment | 
              | Residual Cancer use Neoplasm, Residual | 
              | Residual Chlorine | 
              | Residual Tumor use Neoplasm, Residual | 
              | Residual Volume | 
              | Resilience, Psychological | 
              | Resin Cements | 
              | Resin-Bonded Acid-Etched Fixed Partial Denture use Denture, Partial, Fixed, Resin-Bonded | 
              | Resin-Bonded Bridge use Denture, Partial, Fixed, Resin-Bonded | 
              | Resin-Bonded Fixed Partial Denture use Denture, Partial, Fixed, Resin-Bonded | 
              | Resina itu use Itu | 
              | Resins | 
              | Resins, Plant | 
              | Resins, Synthetic | 
              | Resistance Factors use R Factors | 
              | Resistance Training | 
              | Resistance Transfer Factor use F Factor | 
              | Resistance, Natural use Immunity, Innate | 
              | Resistant Ovary Syndrome use Ovarian Failure, Premature | 
              | Resistin | 
              | Resocyanine use Hymecromone | 
              | Resolutions | 
              | Resolvases, Holliday Junction use Holliday Junction Resolvases | 
              | Resolvases, Transposon use Transposon Resolvases | 
              | Resorcinols | 
              | Resorcinum | 
              | Resorts use Health Resorts | 
              | Resource Allocation | 
              | Resource Guides | 
              | Resource-Based Relative Value Scale use Relative Value Scales | 
              | Resources for Research | 
              | Resources Management | 
              | Respiration | 
              | Respiration Disorders | 
              | Respiration, Artificial | 
              | Respiration, Cell use Cell Respiration | 
              | Respirator Weaning use Ventilator Weaning | 
              | Respirators use Ventilators, Mechanical | 
              | Respirators, Air-Purifying use Respiratory Protective Devices | 
              | Respirators, Industrial use Respiratory Protective Devices | 
              | Respirators, Negative-Pressure use Ventilators, Negative-Pressure | 
              | Respirators, Pulmonary, Negative-Pressure use Ventilators, Negative-Pressure | 
              | Respiratory Acidosis use Acidosis, Respiratory | 
              | Respiratory Airflow use Pulmonary Ventilation | 
              | Respiratory Alkalosis use Alkalosis, Respiratory | 
              | Respiratory Aspiration | 
              | Respiratory Burst | 
              | Respiratory Care Units | 
              | Respiratory Center | 
              | Respiratory Chain use Electron Transport | 
              | Respiratory Chain Deficiencies, Mitochondrial use Mitochondrial Diseases | 
              | Respiratory Circulation use Pulmonary Circulation | 
              | Respiratory Dead Space | 
              | Respiratory Depression use Respiratory Insufficiency | 
              | Respiratory Distress Syndrome, Acute use Respiratory Distress Syndrome, Adult | 
              | Respiratory Distress Syndrome, Adult | 
              | Respiratory Distress Syndrome, Newborn | 
              | Respiratory Drainage, Postural use Drainage, Postural | 
              | Respiratory Drug Administration use Administration, Inhalation | 
              | Respiratory Enteric Orphan Viruses use Reoviridae | 
              | Respiratory Epithelium use Respiratory Mucosa | 
              | Respiratory Failure use Respiratory Insufficiency | 
              | Respiratory Function Tests | 
              | Respiratory Hypersensitivity | 
              | Respiratory Insufficiency | 
              | Respiratory Mechanics | 
              | Respiratory Mucosa | 
              | Respiratory Muscle Training use Breathing Exercises | 
              | Respiratory Muscles | 
              | Respiratory Paralysis | 
              | Respiratory Physiologic Processes use Respiratory Physiological Processes | 
              | Respiratory Physiological Phenomena | 
              | Respiratory Physiological Processes | 
              | Respiratory Physiology use Respiratory Physiological Phenomena | 
              | Respiratory Protective Devices | 
              | Respiratory Sounds | 
              | Respiratory Stimulants use Respiratory System Agents | 
              | Respiratory Syncytial Virus Infections | 
              | Respiratory Syncytial Virus Vaccines | 
              | Respiratory Syncytial Virus, Bovine | 
              | Respiratory Syncytial Virus, Human | 
              | Respiratory Syncytial Viruses | 
              | Respiratory Syndrome, Severe Acute use Severe Acute Respiratory Syndrome | 
              | Respiratory System | 
              | Respiratory System Abnormalities | 
              | Respiratory System Agents | 
              | Respiratory Therapy | 
              | Respiratory Therapy Department, Hospital | 
              | Respiratory Tract Diseases | 
              | Respiratory Tract Fistula | 
              | Respiratory Tract Infections | 
              | Respiratory Tract Neoplasms | 
              | Respiratory Transport | 
              | Respiratory-Gated Imaging Techniques | 
              | Respirovirus | 
              | Respirovirus Infections | 
              | Respite Care | 
              | Response Element, Serum use Serum Response Element | 
              | Response Element, Vitamin D use Vitamin D Response Element | 
              | Response Elements | 
              | Response Latency use Reaction Time | 
              | Response Time use Reaction Time | 
              | Response, Acute-Phase use Acute-Phase Reaction | 
              | Responsibility, Social use Social Responsibility | 
              | Responsible Sex use Safe Sex | 
              | Rest | 
              | Rest Vertical Dimension use Vertical Dimension | 
              | Restaurants | 
              | Resting Phase use G0 Phase | 
              | Resting Potentials use Membrane Potentials | 
              | Resting Tremor use Tremor | 
              | Restless Legs Syndrome | 
              | Restlessness use Psychomotor Agitation | 
              | Reston Ebola virus use Ebolavirus | 
              | Restraint, Physical | 
              | Restriction Endonucleases use DNA Restriction Enzymes | 
              | Restriction Endonucleases, Type I use Deoxyribonucleases, Type I Site-Specific | 
              | Restriction Endonucleases, Type II use Deoxyribonucleases, Type II Site-Specific | 
              | Restriction Endonucleases, Type III use Deoxyribonucleases, Type III Site-Specific | 
              | Restriction Fragment Length Polymorphism use Polymorphism, Restriction Fragment Length | 
              | Restriction Mapping | 
              | Restriction-Modification Systems use DNA Restriction-Modification Enzymes | 
              | Resume, Job use Job Application | 
              | Resurrection Plant use Craterostigma | 
              | Resuscitation | 
              | Resuscitation Decisions use Resuscitation Orders | 
              | Resuscitation Orders | 
              | ret Proto-Oncogene Proteins use Proto-Oncogene Proteins c-ret | 
              | Retainers, Orthodontic use Orthodontic Retainers | 
              | Retardation, Mental use Mental Retardation | 
              | Rete Testis | 
              | Retention (Psychology) | 
              | Reticular Formation | 
              | Reticulate Nuclei of Thalamus use Intralaminar Thalamic Nuclei | 
              | Reticulin | 
              | Reticulocyte Count | 
              | Reticulocytes | 
              | Reticulocytosis | 
              | Reticuloendothelial System use Mononuclear Phagocyte System | 
              | Reticuloendotheliosis virus | 
              | Reticuloendotheliosis Viruses, Avian | 
              | Reticuloendotheliosis, Avian | 
              | Reticuloendotheliosis, Leukemic use Leukemia, Hairy Cell | 
              | Reticulohistiocytoma use Histiocytosis, Non-Langerhans-Cell | 
              | Reticulolymphosarcoma use Lymphoma | 
              | Reticulopodia use Pseudopodia | 
              | Reticulum | 
              | Reticulum Cell-Like Sarcoma, Yoshida use Sarcoma, Yoshida | 
              | Retina | 
              | Retinal use Retinaldehyde | 
              | Retinal Anlage Tumor use Neuroectodermal Tumor, Melanotic | 
              | Retinal Artery | 
              | Retinal Artery Occlusion | 
              | Retinal Bipolar Cells | 
              | Retinal Breaks use Retinal Perforations | 
              | Retinal Cone Photoreceptor Cells | 
              | Retinal Degeneration | 
              | Retinal Dehydrogenase | 
              | Retinal Detachment | 
              | Retinal Dialyses use Retinal Perforations | 
              | Retinal Diseases | 
              | Retinal Disparity use Vision Disparity | 
              | Retinal Drusen | 
              | Retinal Dysplasia | 
              | Retinal Ganglion Cells | 
              | Retinal Hemorrhage | 
              | Retinal Holes use Retinal Perforations | 
              | Retinal Horizontal Cells | 
              | Retinal Necrosis Syndrome, Acute | 
              | Retinal Neoplasms | 
              | Retinal Neovascularization | 
              | Retinal Neurons | 
              | Retinal Perforations | 
              | Retinal Photoreceptor Cell Inner Segment | 
              | Retinal Photoreceptor Cell Outer Segment | 
              | Retinal Photoreceptor Cells use Photoreceptor Cells, Vertebrate | 
              | Retinal Pigment Epithelial Detachment use Retinal Detachment | 
              | Retinal Pigment Epithelium | 
              | Retinal Pigments | 
              | Retinal Rod Cells use Retinal Rod Photoreceptor Cells | 
              | Retinal Rod Photoreceptor Cells | 
              | Retinal S-Antigen use Arrestin | 
              | Retinal Tears use Retinal Perforations | 
              | Retinal Vasculitis | 
              | Retinal Vein | 
              | Retinal Vein Occlusion | 
              | Retinal Vessels | 
              | Retinal-Blood Barrier use Blood-Retinal Barrier | 
              | Retinaldehyde | 
              | Retinene use Retinaldehyde | 
              | Retinitis | 
              | Retinitis Pigmentosa | 
              | Retinitis, Cytomegalovirus use Cytomegalovirus Retinitis | 
              | Retinoblastoma | 
              | Retinoblastoma Genes use Genes, Retinoblastoma | 
              | Retinoblastoma Nuclear Phosphoprotein p105-Rb use Retinoblastoma Protein | 
              | Retinoblastoma Protein | 
              | Retinoblastoma-Like Protein 1 use Retinoblastoma-Like Protein p107 | 
              | Retinoblastoma-Like Protein 2 use Retinoblastoma-Like Protein p130 | 
              | Retinoblastoma-Like Protein p107 | 
              | Retinoblastoma-Like Protein p130 | 
              | Retinoic Acid use Tretinoin | 
              | Retinoic Acid Receptors use Receptors, Retinoic Acid | 
              | Retinoic Acid-Binding Proteins use Receptors, Retinoic Acid | 
              | Retinoid X Receptor use Retinoid X Receptors | 
              | Retinoid X Receptor alpha | 
              | Retinoid X Receptor beta | 
              | Retinoid X Receptor gamma | 
              | Retinoid X Receptors | 
              | Retinoids | 
              | Retinol use Vitamin A | 
              | Retinol O-Fatty-Acyltransferase | 
              | Retinol-Binding Proteins | 
              | Retinol-Binding Proteins, Cellular | 
              | Retinol-Binding Proteins, Plasma | 
              | Retinopathy of Prematurity | 
              | Retinoschisis | 
              | Retinoschisis, Degenerative use Retinoschisis | 
              | Retinoschisis, Juvenile, X-Linked use Retinoschisis | 
              | Retinoscopes | 
              | Retinoscopy | 
              | Retired use Retirement | 
              | Retirement | 
              | Retirement Benefits use Pensions | 
              | Retracted Publication | 
              | Retraction of Publication | 
              | Retraction of Publication as Topic | 
              | Retraining, Professional use Education, Professional, Retraining | 
              | Retreatment | 
              | Retrobulbar Hemorrhage | 
              | Retrobulbar Neuritis use Optic Neuritis | 
              | Retrocochlear Diseases | 
              | Retrocochlear Hearing Loss use Retrocochlear Diseases | 
              | Retroelements | 
              | Retrofitting use Remodeling | 
              | Retrognathism | 
              | Retrograde Amnesia use Amnesia, Retrograde | 
              | Retrograde Degeneration | 
              | Retrograde Degeneration, Transneuronal use Retrograde Degeneration | 
              | Retrograde Obturation | 
              | Retrolental Fibroplasia use Retinopathy of Prematurity | 
              | Retroperitoneal Fibrosis | 
              | Retroperitoneal Neoplasms | 
              | Retroperitoneal Space | 
              | Retropharyngeal Abscess | 
              | Retropneumoperitoneum | 
              | Retroposons use Retroelements | 
              | Retrospective Moral Judgment | 
              | Retrospective Studies | 
              | Retrotransposons use Retroelements | 
              | Retroviridae | 
              | Retroviridae Infections | 
              | Retroviridae Proteins | 
              | Retroviridae Proteins, Oncogenic | 
              | Retrovirus Infections use Retroviridae Infections | 
              | Retrovirus Proteins use Retroviridae Proteins | 
              | Retrovirus-Like Elements use Retroelements | 
              | Retroviruses use Retroviridae | 
              | Retroviruses Type B, Mammalian use Betaretrovirus | 
              | Retroviruses Type C, Avian use Alpharetrovirus | 
              | Retroviruses Type C, Mammalian use Gammaretrovirus | 
              | Retroviruses Type D use Betaretrovirus | 
              | Retroviruses, Endogenous use Endogenous Retroviruses | 
              | Retroviruses, Simian | 
              | Rett Syndrome | 
              | Return of Old Symptoms use Old Symptoms Return | 
              | Returnee | 
              | Returning State | 
              | Reuniens Thalamic Nucleus use Midline Thalamic Nuclei | 
              | Reunion | 
              | Reuptake Inhibitors, Neurotransmitter use Neurotransmitter Uptake Inhibitors | 
              | Reusable Solid Wastes use Solid Waste Use | 
              | Reuse use Recycling (Environmental Health) | 
              | Reused Water use Wastewater Use | 
              | rev Gene Products use Gene Products, rev | 
              | rev Gene Products, Human Immunodeficiency Virus | 
              | rev Genes use Genes, rev | 
              | rev Protein use Gene Products, rev | 
              | rev-Responsive Element use Genes, env | 
              | Revalidation of the Products Registration | 
              | Reversal Learning | 
              | Reverse Geologic Fault use Geologic Fault, Reverse | 
              | Reverse Immunoblotting use Immunoblotting | 
              | Reverse One-Hybrid System Techniques use Two-Hybrid System Techniques | 
              | Reverse Osmosis | 
              | Reverse T3 Thyroid hormone use Triiodothyronine, Reverse | 
              | Reverse Transcriptase use RNA-Directed DNA Polymerase | 
              | Reverse Transcriptase Inhibitors | 
              | Reverse Transcriptase Polymerase Chain Reaction | 
              | Reverse Transcription | 
              | Reverse Triiodothyronine use Triiodothyronine, Reverse | 
              | Reverse Two-Hybrid System Techniques use Two-Hybrid System Techniques | 
              | Reversible Inhibitors of Monoamine Oxidase use Monoamine Oxidase Inhibitors | 
              | Review | 
              | Review Literature as Topic | 
              | Revision, Joint use Reoperation | 
              | Revision, Surgical use Reoperation | 
              | Revolutionary War use American Revolution | 
              | Reward | 
              | Rewarming | 
              | rex Gene Products use Gene Products, rex | 
              | rex Genes use Genes, pX | 
              | rex Protein use Gene Products, rex | 
              | Reye Syndrome | 
              | Reynolds Number | 
              | RFLP use Polymorphism, Restriction Fragment Length | 
              | RGS Proteins | 
              | Rh Factors use Rh-Hr Blood-Group System | 
              | Rh Immune Globulin use Rho(D) Immune Globulin | 
              | Rh Isoimmunization | 
              | Rh-Hr Blood-Group System | 
              | Rhabdiasoidea | 
              | Rhabditida | 
              | Rhabditida Infections | 
              | Rhabditis use Rhabditoidea | 
              | Rhabditoidea | 
              | Rhabdoid Tumor | 
              | Rhabdomyolysis | 
              | Rhabdomyoma | 
              | Rhabdomyosarcoma | 
              | Rhabdomyosarcoma, Alveolar | 
              | Rhabdomyosarcoma, Embryonal | 
              | Rhabdoviridae | 
              | Rhabdoviridae Infections | 
              | Rhadinovirus | 
              | Rhagoletis use Tephritidae | 
              | Rhammus purshiana use Frangula | 
              | Rhamnaceae | 
              | Rhamnose | 
              | Rhamnus | 
              | Rhamnus californica | 
              | Rhamnus cathartica | 
              | Rhamnus frangula | 
              | Rhamnus purshiana use Cascara sagrada | 
              | Rhatany use Krameriaceae | 
              | Rhazya use Apocynaceae | 
              | Rheas use Rheiformes | 
              | Rheedia use Clusiaceae | 
              | Rheiformes | 
              | Rhenium | 
              | Rheography use Plethysmography, Impedance | 
              | Rheology | 
              | Rhesus Blood-Group System use Rh-Hr Blood-Group System | 
              | Rhesus Monkey use Macaca mulatta | 
              | Rhetinic Acid use Glycyrrhetinic Acid | 
              | Rheum | 
              | Rheum Emodin use Emodin | 
              | Rheum palmatum | 
              | Rheumatic Diseases | 
              | Rheumatic Fever | 
              | Rheumatic Heart Disease | 
              | Rheumatic Nodule | 
              | Rheumatism use Rheumatic Diseases | 
              | Rheumatism, Articular, Acute use Rheumatic Fever | 
              | Rheumatism, Muscular use Fibromyalgia | 
              | Rheumatism, Peri-Extra-Articular use Polymyalgia Rheumatica | 
              | Rheumatoid Arthritis use Arthritis, Rheumatoid | 
              | Rheumatoid Factor | 
              | Rheumatoid Nodule | 
              | Rheumatoid Purpura use Purpura, Schoenlein-Henoch | 
              | Rheumatoid Spondylitis use Spondylitis, Ankylosing | 
              | Rheumatology | 
              | Rhinencephalon use Olfactory Pathways | 
              | Rhinitis | 
              | Rhinitis, Allergic, Nonseasonal use Rhinitis, Allergic, Perennial | 
              | Rhinitis, Allergic, Perennial | 
              | Rhinitis, Allergic, Seasonal | 
              | Rhinitis, Atrophic | 
              | Rhinitis, Vasomotor | 
              | Rhinolophus use Chiroptera | 
              | Rhinomanometry | 
              | Rhinometry, Acoustic | 
              | Rhinopharynx use Nasopharynx | 
              | Rhinophyma | 
              | Rhinoplasty | 
              | Rhinoscleroma | 
              | Rhinosporidiosis | 
              | Rhinosporidium | 
              | Rhinotracheitis Virus, Turkey use Metapneumovirus | 
              | Rhinovirus | 
              | Rhipicephalus | 
              | Rhipicephalus sanguineus | 
              | Rhizobiaceae | 
              | Rhizobium | 
              | Rhizobium etli | 
              | Rhizobium galegae use Rhizobium | 
              | Rhizobium leguminosarum | 
              | Rhizobium lupini use Rhizobium | 
              | Rhizobium meliloti use Sinorhizobium meliloti | 
              | Rhizobium phaseoli | 
              | Rhizobium radiobacter | 
              | Rhizobium tropici | 
              | Rhizoctonia | 
              | Rhizoma Pinelliae use Pinellia | 
              | Rhizome | 
              | Rhizomelic Chondrodysplasia Punctata use Chondrodysplasia Punctata, Rhizomelic | 
              | Rhizomucor | 
              | Rhizophora use Rhizophoraceae | 
              | Rhizophora mangle use Rhizophoraceae | 
              | Rhizophoraceae | 
              | Rhizopus | 
              | Rhizotomy | 
              | Rho Factor | 
              | rho G-Proteins use rho GTP-Binding Proteins | 
              | rho GTP-Binding Proteins | 
              | rho GTPases use rho GTP-Binding Proteins | 
              | rho Small GTP-Binding Proteins use rho GTP-Binding Proteins | 
              | Rho(D) Immune Globulin | 
              | rho-Associated Kinase use rho-Associated Kinases | 
              | rho-Associated Kinases | 
              | rho12 GTP-Binding Protein use rhoA GTP-Binding Protein | 
              | rhoA GTP-Binding Protein | 
              | rhoB GTP-Binding Protein | 
              | Rhodallinum use Thiosinaminum | 
              | Rhodamine 123 | 
              | Rhodamines | 
              | Rhodanates use Thiocyanates | 
              | Rhodanese use Thiosulfate Sulfurtransferase | 
              | Rhodanine | 
              | Rhode Island | 
              | Rhodesia, Northern use Zambia | 
              | Rhodesia, Southern use Zimbabwe | 
              | Rhodiola | 
              | Rhodium | 
              | Rhodium Metallicum | 
              | Rhodium Oxydatum Nitricum | 
              | Rhodnius | 
              | Rhodobacter | 
              | Rhodobacter capsulatus | 
              | Rhodobacter sphaeroides | 
              | Rhodobacteraceae | 
              | Rhodococcus | 
              | Rhodococcus equi | 
              | Rhodocyclaceae | 
              | Rhodocyclus use Rhodocyclaceae | 
              | Rhododendron | 
              | Rhododendron chrysanthum | 
              | Rhodomicrobium | 
              | Rhodomicrobium vannielii use Rhodomicrobium | 
              | Rhodophyta use Algae, Red | 
              | Rhodopseudomonas | 
              | Rhodopseudomonas capsulatus use Rhodobacter capsulatus | 
              | Rhodopseudomonas sphaeroides use Rhodobacter sphaeroides | 
              | Rhodopsin | 
              | Rhodopsin Kinase use G-Protein-Coupled Receptor Kinase 1 | 
              | Rhodopsins, Microbial | 
              | Rhodospirillaceae | 
              | Rhodospirillales | 
              | Rhodospirillum | 
              | Rhodospirillum centenum | 
              | Rhodospirillum rubrum | 
              | Rhodothermus | 
              | Rhodotorula | 
              | Rhodovulum | 
              | rhoGAP2 Protein use Chimerin 1 | 
              | Rhombencephalic Sleep use Sleep, REM | 
              | Rhombencephalon | 
              | Rhomboid Thalamic Nucleus use Midline Thalamic Nuclei | 
              | Rhonchi use Respiratory Sounds | 
              | Rhubarb use Rheum | 
              | Rhus | 
              | Rhus aromatica | 
              | Rhus cotinus | 
              | Rhus Dermatitis use Dermatitis, Toxicodendron | 
              | Rhus diversiloba | 
              | Rhus glabra | 
              | Rhus laurina | 
              | Rhus radicans | 
              | Rhus toxicodendron | 
              | Rhus venenata | 
              | Rhus vernix | 
              | Rhyncophthirina use Lice | 
              | Rhythmicity use Periodicity | 
              | Rhytidectomy use Rhytidoplasty | 
              | Rhytidoplasty | 
              | Rib Fractures | 
              | Ribavirin | 
              | Ribes | 
              | Ribitol | 
              | Riboflavin | 
              | Riboflavin Deficiency | 
              | Riboflavin Synthase | 
              | Ribonuclease A use Ribonuclease, Pancreatic | 
              | Ribonuclease H | 
              | Ribonuclease H, Calf Thymus use Ribonuclease H | 
              | Ribonuclease H, Human Immunodeficiency Virus | 
              | Ribonuclease III | 
              | Ribonuclease N1 use Ribonuclease T1 | 
              | Ribonuclease P | 
              | Ribonuclease P, RNA Catalytic Subunit use Ribonuclease P | 
              | Ribonuclease T1 | 
              | Ribonuclease, Pancreatic | 
              | Ribonucleases | 
              | Ribonucleic Acid use RNA | 
              | Ribonucleic Acid Regulatory Sequences use Regulatory Sequences, Ribonucleic Acid | 
              | Ribonucleoprotein Particles, Vault use Vault Ribonucleoprotein Particles | 
              | Ribonucleoprotein, U1 Small Nuclear | 
              | Ribonucleoprotein, U2 Small Nuclear | 
              | Ribonucleoprotein, U4-U6 Small Nuclear | 
              | Ribonucleoprotein, U5 Small Nuclear | 
              | Ribonucleoprotein, U7 Small Nuclear | 
              | Ribonucleoproteins | 
              | Ribonucleoproteins, Small Cytoplasmic | 
              | Ribonucleoproteins, Small Nuclear | 
              | Ribonucleoproteins, Small Nucleolar | 
              | Ribonucleoproteins, U4 Small Nuclear use Ribonucleoprotein, U4-U6 Small Nuclear | 
              | Ribonucleoproteins, U6 Small Nuclear use Ribonucleoprotein, U4-U6 Small Nuclear | 
              | Ribonucleoside Diphosphate Reductase | 
              | Ribonucleoside Phosphates use Ribonucleotides | 
              | Ribonucleosides | 
              | Ribonucleotide Reductases | 
              | Ribonucleotides | 
              | Ribose | 
              | Ribose-Phosphate Pyrophosphokinase | 
              | Ribosemonophosphates | 
              | Ribosomal DNA use DNA, Ribosomal | 
              | Ribosomal Frameshifting use Frameshifting, Ribosomal | 
              | Ribosomal Protein S6 | 
              | Ribosomal Protein S6 Kinases | 
              | Ribosomal Protein S6 Kinases, 70-kDa | 
              | Ribosomal Protein S6 Kinases, 90-kDa | 
              | Ribosomal Proteins | 
              | Ribosomal RNA use RNA, Ribosomal | 
              | Ribosomal Spacer DNA use DNA, Ribosomal Spacer | 
              | Ribosome Inactivating Proteins | 
              | Ribosome Inactivating Proteins, Type 1 | 
              | Ribosome Inactivating Proteins, Type 2 | 
              | Ribosome Subunits | 
              | Ribosome Subunits, Large | 
              | Ribosome Subunits, Large, Archaeal | 
              | Ribosome Subunits, Large, Bacterial | 
              | Ribosome Subunits, Large, Eukaryotic | 
              | Ribosome Subunits, Small | 
              | Ribosome Subunits, Small, Archaeal | 
              | Ribosome Subunits, Small, Bacterial | 
              | Ribosome Subunits, Small, Eukaryotic | 
              | Ribosomes | 
              | Ribostamycin | 
              | Ribosylhypoxanthine Monophosphate use Inosine Monophosphate | 
              | Ribotyping | 
              | Ribovirin use Ribavirin | 
              | Ribozymes use RNA, Catalytic | 
              | Ribs | 
              | Ribulose Biphosphate Carboxylase-Oxygenase use Ribulose-Bisphosphate Carboxylase | 
              | Ribulose Diphosphate Carboxylase use Ribulose-Bisphosphate Carboxylase | 
              | Ribulose-Bisphosphate Carboxylase | 
              | Ribulosebiphosphate Carboxylase use Ribulose-Bisphosphate Carboxylase | 
              | Ribulosephosphates | 
              | Rice use Oryza sativa | 
              | Rice stripe virus use Tenuivirus | 
              | Rice Tungro Bacilliform Virus use Tungrovirus | 
              | Rice tungro spherical virus use Waikavirus | 
              | Richter Scale | 
              | Ricin | 
              | Ricinoleic Acids | 
              | Ricinus | 
              | Ricinus communis | 
              | Rickets | 
              | Rickets, Hypophosphatemic use Hypophosphatemic Rickets, X-Linked Dominant | 
              | Rickets, Renal use Renal Osteodystrophy | 
              | Rickets, Vitamin D-Resistant use Hypophosphatemic Rickets, X-Linked Dominant | 
              | Rickets, X-Linked Hypophosphatemic use Hypophosphatemic Rickets, X-Linked Dominant | 
              | Rickettsia | 
              | Rickettsia akari | 
              | Rickettsia conorii | 
              | Rickettsia felis | 
              | Rickettsia Infections | 
              | Rickettsia prowazekii | 
              | Rickettsia quintana use Bartonella quintana | 
              | Rickettsia rickettsii | 
              | Rickettsia tsutsugamushi use Orientia tsutsugamushi | 
              | Rickettsia typhi | 
              | Rickettsiaceae | 
              | Rickettsiaceae Infections | 
              | Rickettsial Pneumonia use Pneumonia, Rickettsial | 
              | Rickettsial Vaccines | 
              | Rickettsialpox use Rickettsiaceae Infections | 
              | Rickettsieae | 
              | Rickettsiella use Coxiellaceae | 
              | RICYT use Network on Science and Technology Indicators - Ibero-American and Inter-American | 
              | Rida use Scrapie | 
              | Ridge use Oceanic Ridge | 
              | Rietveld Refinement use Least-Squares Analysis | 
              | Rifabutin | 
              | Rifampicin use Rifampin | 
              | Rifampin | 
              | Rifamycins | 
              | Rifles use Firearms | 
              | Rifomycins use Rifamycins | 
              | Rift Valley Fever | 
              | Rift Valley fever virus | 
              | Right Atrial Function use Atrial Function, Right | 
              | Right Heart Bypass use Heart Bypass, Right | 
              | Right to Die | 
              | Right to Health | 
              | Right to Treatment use Patient Rights | 
              | Right Ventricular Dysfunction use Ventricular Dysfunction, Right | 
              | Right Ventricular Dysplasia, Arrhythmogenic use Arrhythmogenic Right Ventricular Dysplasia | 
              | Right Ventricular Function use Ventricular Function, Right | 
              | Right Ventricular Hypertrophy use Hypertrophy, Right Ventricular | 
              | Right Whale Dolphins use Dolphins | 
              | Right Whale, Greenland use Bowhead Whale | 
              | Right Whale, North Atlantic use Whales | 
              | Right Whale, Southern use Whales | 
              | Rights of the Handicapped use Handicapped Advocacy | 
              | Rightsizing use Personnel Downsizing | 
              | Rigidity, Decerebrate use Decerebrate State | 
              | Rigidity, Decorticate use Decerebrate State | 
              | Rigidity, Muscular use Muscle Rigidity | 
              | Rigor Mortis | 
              | Riley Virus use Lactate dehydrogenase-elevating virus | 
              | Riley-Day Syndrome use Dysautonomia, Familial | 
              | Riluzole | 
              | Rimantadine | 
              | Rinderpest | 
              | Rinderpest virus | 
              | Ring Chromosomes | 
              | Ring Constrictions, Intrauterine use Amniotic Band Syndrome | 
              | RING Finger Domains | 
              | RING Finger Motifs use RING Finger Domains | 
              | Ringelman Chart | 
              | Ringelman Scale use Ringelman Chart | 
              | Ringtails use Procyonidae | 
              | Ringworm use Tinea | 
              | Rio Muni use Equatorial Guinea | 
              | Rioprostil | 
              | Riot Control Agents, Chemical | 
              | Riots | 
              | RIP Serine-Threonine Kinases use Receptor-Interacting Protein Serine-Threonine Kinases | 
              | Rising Tide | 
              | Risk | 
              | Risk Acceptance use Risk-Taking | 
              | Risk Adjustment | 
              | Risk Areas Delimitation | 
              | Risk Assessment | 
              | Risk Behavior use Risk-Taking | 
              | Risk Exposure use Risk-Taking | 
              | Risk Factors | 
              | Risk Grade | 
              | Risk Grade I | 
              | Risk Grade II | 
              | Risk Groups | 
              | Risk Groups Nutrition | 
              | Risk Index | 
              | Risk Management | 
              | Risk Map | 
              | Risk of Biological Agents use Exposure to Biological Agents | 
              | Risk Rate use Risk Index | 
              | Risk Ratio use Odds Ratio | 
              | Risk Reduction use Risk Reduction Behavior | 
              | Risk Reduction Behavior | 
              | Risk Sharing, Financial | 
              | Risk Zone | 
              | Risk-Benefit Assessment use Risk Assessment | 
              | Risk-Taking | 
              | Risperidone | 
              | Risso's Dolphin use Dolphins | 
              | Ristocetin | 
              | Ritanserin | 
              | Ritodrine | 
              | Ritonavir | 
              | Ritter Disease use Staphylococcal Scalded Skin Syndrome | 
              | Rituals use Ceremonial Behavior | 
              | Rivea use Convolvulaceae | 
              | River Basins | 
              | River Bed | 
              | River Blindness use Onchocerciasis, Ocular | 
              | River Forecast use Hydrological Forecast | 
              | River Mouth use Delta | 
              | River Otters use Otters | 
              | River Pollution | 
              | River Water Collection | 
              | Rivers | 
              | RNA | 
              | RNA 3' End Processing | 
              | RNA 3' Polyadenylation Signals | 
              | RNA 5' Terminal Oligopyrimidine Sequence | 
              | RNA Amplification Techniques use Nucleic Acid Amplification Techniques | 
              | RNA Aptamers use Aptamers, Nucleotide | 
              | RNA Cap Analogs | 
              | RNA Cap-Binding Proteins | 
              | RNA Caps | 
              | RNA Computers use Computers, Molecular | 
              | RNA Databases use Databases, Nucleic Acid | 
              | RNA Decay use RNA Stability | 
              | RNA Denaturation use Nucleic Acid Denaturation | 
              | RNA Editing | 
              | RNA Helicases | 
              | RNA Interference | 
              | RNA Ligase (ATP) | 
              | RNA Methylases use tRNA Methyltransferases | 
              | RNA N-Glycosidase use Ribosome Inactivating Proteins | 
              | RNA Nucleotidyltransferases | 
              | RNA Phages | 
              | RNA Polymerase I | 
              | RNA Polymerase II | 
              | RNA Polymerase III | 
              | RNA Polymerase Sigma 54 | 
              | RNA Polymerases use DNA-Directed RNA Polymerases | 
              | RNA Precursors | 
              | RNA Probes | 
              | RNA Processing, Post-Transcriptional | 
              | RNA Regulatory Sequences use Regulatory Sequences, Ribonucleic Acid | 
              | RNA Replicase | 
              | RNA Rodent Viruses use RNA Viruses | 
              | RNA Sequence use Base Sequence | 
              | RNA Sequence Analysis use Sequence Analysis, RNA | 
              | RNA Splice Sites | 
              | RNA Splicing | 
              | RNA Splicing, Alternative use Alternative Splicing | 
              | RNA Stability | 
              | RNA Synthesis Inhibitors use Nucleic Acid Synthesis Inhibitors | 
              | RNA trans-Splicing use Trans-Splicing | 
              | RNA Transport | 
              | RNA Tumor Viruses use Retroviridae | 
              | RNA Virus Infections | 
              | RNA Viruses | 
              | RNA, Algal | 
              | RNA, Antisense | 
              | RNA, Archaeal | 
              | RNA, Bacterial | 
              | RNA, Catalytic | 
              | RNA, Chloroplast | 
              | RNA, Chromosomal use RNA, Nuclear | 
              | RNA, Complementary | 
              | RNA, Double-Stranded | 
              | RNA, Fungal | 
              | RNA, Guide | 
              | RNA, Helminth | 
              | RNA, Heterogeneous Nuclear | 
              | RNA, Messenger | 
              | RNA, Messenger, Editing use RNA Editing | 
              | RNA, Messenger, Masked use RNA, Messenger, Stored | 
              | RNA, Messenger, Maternal use RNA, Messenger, Stored | 
              | RNA, Messenger, Paternal use RNA, Messenger, Stored | 
              | RNA, Messenger, Polyadenylated use RNA, Messenger | 
              | RNA, Messenger, Precursors use RNA Precursors | 
              | RNA, Messenger, Splicing use RNA Splicing | 
              | RNA, Messenger, Stored | 
              | RNA, Neoplasm | 
              | RNA, Non-Polyadenylated use RNA | 
              | RNA, Nuclear | 
              | RNA, Piwi-Interacting use RNA, Small Interfering | 
              | RNA, Plant | 
              | RNA, Polyadenylated use RNA, Messenger | 
              | RNA, Protozoan | 
              | RNA, Ribosomal | 
              | RNA, Ribosomal, 16S | 
              | RNA, Ribosomal, 18S | 
              | RNA, Ribosomal, 23S | 
              | RNA, Ribosomal, 28S | 
              | RNA, Ribosomal, 5.8S | 
              | RNA, Ribosomal, 5S | 
              | RNA, Ribosomal, Precursors use RNA Precursors | 
              | RNA, Ribosomal, Self-Splicing | 
              | RNA, Satellite | 
              | RNA, Scan use RNA, Small Interfering | 
              | RNA, Small Cytoplasmic | 
              | RNA, Small Interfering | 
              | RNA, Small Nuclear | 
              | RNA, Small Nuclear, Precursors use RNA Precursors | 
              | RNA, Small Nucleolar | 
              | RNA, Small Temporal use MicroRNAs | 
              | RNA, Spliced Leader | 
              | RNA, Transfer | 
              | RNA, Transfer, Ala | 
              | RNA, Transfer, Amino Acid-Specific | 
              | RNA, Transfer, Amino Acyl | 
              | RNA, Transfer, Arg | 
              | RNA, Transfer, Asn | 
              | RNA, Transfer, Asp | 
              | RNA, Transfer, Cys | 
              | RNA, Transfer, Gln | 
              | RNA, Transfer, Glu | 
              | RNA, Transfer, Gly | 
              | RNA, Transfer, His | 
              | RNA, Transfer, Ile | 
              | RNA, Transfer, Initiator use RNA, Transfer, Met | 
              | RNA, Transfer, Leu | 
              | RNA, Transfer, Lys | 
              | RNA, Transfer, Met | 
              | RNA, Transfer, Methyltransferases use tRNA Methyltransferases | 
              | RNA, Transfer, Phe | 
              | RNA, Transfer, Precursors use RNA Precursors | 
              | RNA, Transfer, Pro | 
              | RNA, Transfer, Ser | 
              | RNA, Transfer, Thr | 
              | RNA, Transfer, Trp | 
              | RNA, Transfer, Tyr | 
              | RNA, Transfer, Val | 
              | RNA, Untranslated | 
              | RNA, Viral | 
              | RNA-Binding Protein EWS | 
              | RNA-Binding Protein FUS | 
              | RNA-Binding Proteins | 
              | RNA-Dependent DNA Polymerase use RNA-Directed DNA Polymerase | 
              | RNA-Dependent Protein Kinase use eIF-2 Kinase | 
              | RNA-Dependent RNA Polymerase use RNA Replicase | 
              | RNA-Directed DNA Polymerase | 
              | RNA-Induced Silencing Complex | 
              | RNase use Ribonucleases | 
              | RNase A use Ribonuclease, Pancreatic | 
              | RNase H use Ribonuclease H | 
              | RNase T1 use Ribonuclease T1 | 
              | Roach (Fish) use Cyprinidae | 
              | Roads | 
              | Robenidine | 
              | Robenzidene use Robenidine | 
              | Robenzidine use Robenidine | 
              | Robinia | 
              | Robinia pseudacacia | 
              | Robins use Songbirds | 
              | Robotics | 
              | ROC Analysis use ROC Curve | 
              | ROC Curve | 
              | Rochalimaea use Bartonella | 
              | Rochalimaea henselae use Bartonella henselae | 
              | Rochalimaea Infections use Bartonella Infections | 
              | Rochalimaea quintana use Bartonella quintana | 
              | Rock Decomposition | 
              | Rock Shrimp use Decapoda (Crustacea) | 
              | Rock Slide use Landslides | 
              | Rocket, Yellow use Barbarea | 
              | Rockfall | 
              | Rockslide use Rockfall | 
              | Rocky Mountain Bighorn Sheep use Sheep, Bighorn | 
              | Rocky Mountain Spotted Fever | 
              | Rod Cell Inner Segment use Retinal Photoreceptor Cell Inner Segment | 
              | Rod Cell Outer Segment | 
              | Rod Opsins | 
              | Rod Outer Segment use Rod Cell Outer Segment | 
              | Rod Photoreceptors use Retinal Rod Photoreceptor Cells | 
              | Rod Vision use Night Vision | 
              | Rod-Cone Dystrophy use Retinitis Pigmentosa | 
              | Rod-Cone Interaction | 
              | Rod-Opsin use Rod Opsins | 
              | Rodent Control | 
              | Rodent Diseases | 
              | Rodent Ulcer use Carcinoma, Basal Cell | 
              | Rodentia | 
              | Rodenticides | 
              | Rodents use Rodentia | 
              | Rods (Retina) use Retinal Rod Photoreceptor Cells | 
              | Rods and Cones use Photoreceptor Cells, Vertebrate | 
              | Roentgen Rays use X-Rays | 
              | Roentgenkymography use Electrokymography | 
              | Roentgenography use Radiography | 
              | Roentgenotherapy use X-Ray Therapy | 
              | Rogerian Therapy use Nondirective Therapy | 
              | Rohypnol use Flunitrazepam | 
              | Rolands Epilepsy use Epilepsy, Rolandic | 
              | Role | 
              | Role Concept use Role | 
              | Role Playing | 
              | Rolipram | 
              | Rolitetracycline | 
              | Roller | 
              | Rollinia | 
              | Romaleidae use Grasshoppers | 
              | Roman Chamomile use Anthemis nobilis (Homeopathy) | 
              | Roman Empire use Roman World | 
              | Roman World | 
              | Romania | 
              | Romano-Ward Syndrome | 
              | Romanomermis use Mermithoidea | 
              | Romberg Disease use Facial Hemiatrophy | 
              | Rome | 
              | Ronidazole | 
              | Roniviridae | 
              | Rooibos use Aspalathus | 
              | Rooming-in Care | 
              | Rooms, Patient use Patients' Rooms | 
              | Root Canal use Dental Pulp Cavity | 
              | Root Canal Filling Materials | 
              | Root Canal Irrigants | 
              | Root Canal Medicaments use Root Canal Irrigants | 
              | Root Canal Obturation | 
              | Root Canal Preparation | 
              | Root Canal Sealants use Root Canal Filling Materials | 
              | Root Canal Therapy | 
              | Root Caries | 
              | Root Nodules, Plant | 
              | Root Planing | 
              | Root Resorption | 
              | Root Scaling use Dental Scaling | 
              | Root Tip use Meristem | 
              | Rorippa | 
              | Rorschach Test | 
              | Rosa | 
              | Rosa canina | 
              | Rosa centifolia | 
              | Rosa damascena | 
              | Rosacea | 
              | Rosaceae | 
              | Rosai-Dorfman Disease use Histiocytosis, Sinus | 
              | Rosales | 
              | Rosaniline Dyes | 
              | Rose use Rosa | 
              | Rose Bengal | 
              | Rosehips use Rosa | 
              | Rosenthal Syndrome use Factor XI Deficiency | 
              | Rosenzweig Picture-Frustration Study use Projective Techniques | 
              | Roseobacter | 
              | Roseola Infantum use Exanthema Subitum | 
              | Roseolovirus | 
              | Roseolovirus Infections | 
              | Roseomonas use Methylobacteriaceae | 
              | Roseroot use Rhodiola | 
              | Rosette Formation | 
              | Rosmarinus | 
              | Rosmarinus officinalis | 
              | Ross River virus | 
              | Rostral Intralaminar Nuclei use Intralaminar Thalamic Nuclei | 
              | Rotameters | 
              | Rotarod Performance Test | 
              | Rotary Disks | 
              | Rotary Drilling | 
              | Rotary Nystagmus use Nystagmus, Pathologic | 
              | Rotary Pumps | 
              | Rotation | 
              | Rotational Atherectomy use Atherectomy, Coronary | 
              | Rotator Cuff | 
              | Rotavirus | 
              | Rotavirus Infections | 
              | Rotavirus Vaccines | 
              | Rotaxanes | 
              | Rotenone | 
              | Rothmund-Thomson Syndrome | 
              | Rotifera | 
              | Rotifers use Rotifera | 
              | Rotor Syndrome use Hyperbilirubinemia, Hereditary | 
              | Rouges use Products for Facial Makeup | 
              | Rouget Cells use Pericytes | 
              | Rough-Toothed Dolphin use Dolphins | 
              | Roughage use Dietary Fiber | 
              | Round Ligament | 
              | Round Window, Ear | 
              | Rounded Crested Weirs | 
              | Rourea use Connaraceae | 
              | Rous Sarcoma use Sarcoma, Avian | 
              | Rous sarcoma virus | 
              | Rous-Associated Virus use Avian leukosis virus | 
              | Rousettus use Chiroptera | 
              | Roussy-Levy Syndrome use Charcot-Marie-Tooth Disease | 
              | Routine Diagnostic Tests use Diagnostic Tests, Routine | 
              | Routing use Flood Routing | 
              | Roux-en-Y Anastomosis use Anastomosis, Roux-en-Y | 
              | Roux-en-Y Diversion use Anastomosis, Roux-en-Y | 
              | Roux-en-Y Loop use Anastomosis, Roux-en-Y | 
              | Rowan use Sorbus | 
              | Rowson-Parr Virus use Friend murine leukemia virus | 
              | Roxarsone | 
              | Roxithromycin | 
              | Royer Syndrome use Prader-Willi Syndrome | 
              | rRNA Genes use Genes, rRNA | 
              | rRNA Operon | 
              | rRNA Promoter use Promoter Regions, Genetic | 
              | RSH Syndrome use Smith-Lemli-Opitz Syndrome | 
              | RSV Vaccines use Respiratory Syncytial Virus Vaccines | 
              | RT-PCR use Reverse Transcriptase Polymerase Chain Reaction | 
              | Ruanda use Rwanda | 
              | Rubber | 
              | Rubber Allergy use Latex Hypersensitivity | 
              | Rubber Dams | 
              | Rubber Industry | 
              | Rubber Silicone use Silicone Elastomers | 
              | Rubber Tires use Tires | 
              | Rubber Tree use Hevea | 
              | Rubberplant use Ficus | 
              | Rubefacients use Irritants | 
              | Rubella | 
              | Rubella Syndrome, Congenital | 
              | Rubella Vaccine | 
              | Rubella virus | 
              | Rubeola use Measles | 
              | Rubia | 
              | Rubia tinctorum | 
              | Rubiaceae | 
              | Rubidium | 
              | Rubidium Radioisotopes | 
              | Rubidomycin use Daunorubicin | 
              | Rubinstein-Taybi Syndrome | 
              | Rubisco use Ribulose-Bisphosphate Carboxylase | 
              | Rubivirus | 
              | Rubivirus Infections | 
              | Rubomycin use Daunorubicin | 
              | Rubredoxins | 
              | Rubulavirus | 
              | Rubulavirus Infections | 
              | Rubus villosus | 
              | Ruby Lasers use Lasers, Solid-State | 
              | Rudbeckia | 
              | Rudbeckia angustifolia use Echinacea angustifolia | 
              | Rudbeckia hirta | 
              | Rudbeckia purpurea use Echinacea | 
              | Rudiviridae | 
              | Rudivirus use Rudiviridae | 
              | Rudolphi's Rorqual use Balaenoptera | 
              | Rue use Ruta | 
              | Rue, Goat's use Galega | 
              | Rue, Meadow use Thalictrum | 
              | Ruellia use Acanthaceae | 
              | Ruffini's Corpuscles use Mechanoreceptors | 
              | Rufocromomycin use Streptonigrin | 
              | Rugby use Football | 
              | Rumania use Romania | 
              | Rumen | 
              | Rumex | 
              | Rumex acetosa | 
              | Rumex crispus | 
              | Rumex obtusifolius use Lapathum acutum | 
              | Ruminantia use Ruminants | 
              | Ruminants | 
              | Rumination Disorders use Feeding and Eating Disorders of Childhood | 
              | Ruminococcus | 
              | Runaway Behavior | 
              | Running | 
              | Runoff | 
              | Runoff Coefficient | 
              | Runt Disease use Graft vs Host Disease | 
              | Rupicapra | 
              | Ruppia use Alismatidae | 
              | Rupture | 
              | Rupture, Spontaneous | 
              | Rural Communities use Rural Settlements | 
              | Rural Development | 
              | Rural Economy | 
              | Rural Health | 
              | Rural Health Services | 
              | Rural Hospitals use Hospitals, Rural | 
              | Rural Planning | 
              | Rural Population | 
              | Rural Population Health use Rural Health | 
              | Rural Sanitation | 
              | Rural Settlements | 
              | Rural Water Supply use Water Supply, Rural | 
              | Rural Workers | 
              | Rural Zones | 
              | Rural-Rural Migration use Internal Migration | 
              | Rural-Urban Migration | 
              | Ruscus | 
              | Russell's Viper | 
              | Russell's Viper Venom Time use Prothrombin Time | 
              | Russia | 
              | Russia (Pre-1917) | 
              | Russian Orthodoxy use Eastern Orthodoxy | 
              | Russian S.F.S.R. use Russia | 
              | Russian S.F.S.R., Asian use Siberia | 
              | Russian-Japanese War | 
              | Russula emetica use Agaricus emeticus | 
              | Russula foetens | 
              | Rut Behavior use Sexual Behavior, Animal | 
              | Ruta | 
              | Ruta graveolens | 
              | Rutabaga use Brassica napus | 
              | Rutaceae | 
              | Rutamycin | 
              | Ruthenium | 
              | Ruthenium Compounds | 
              | Ruthenium Radioisotopes | 
              | Ruthenium Red | 
              | Rutin | 
              | Rwanda | 
              | Ryania | 
              | Ryanodine | 
              | Ryanodine Receptor 1 use Ryanodine Receptor Calcium Release Channel | 
              | Ryanodine Receptor 2 use Ryanodine Receptor Calcium Release Channel | 
              | Ryanodine Receptor 3 use Ryanodine Receptor Calcium Release Channel | 
              | Ryanodine Receptor Calcium Release Channel | 
              | Ryanodine Receptors use Ryanodine Receptor Calcium Release Channel | 
              | Rye use Secale cereale | 
              | Ryegrass use Lolium | 
              | Rymovirus use Potyviridae | 
              | RyR1 use Ryanodine Receptor Calcium Release Channel |