| U-Plasminogen Activator use Urokinase-Type Plasminogen Activator | 
              | U1 Small Nuclear Ribonucleoproteins use Ribonucleoprotein, U1 Small Nuclear | 
              | U1 snRNP use Ribonucleoprotein, U1 Small Nuclear | 
              | U2 Small Nuclear Ribonucleoproteins use Ribonucleoprotein, U2 Small Nuclear | 
              | U2 snRNP use Ribonucleoprotein, U2 Small Nuclear | 
              | U4 Small Nuclear Ribonucleoproteins use Ribonucleoprotein, U4-U6 Small Nuclear | 
              | U4 snRNP use Ribonucleoprotein, U4-U6 Small Nuclear | 
              | U4-U6 Small Nuclear Ribonucleoproteins use Ribonucleoprotein, U4-U6 Small Nuclear | 
              | U4-U6 snRNP use Ribonucleoprotein, U4-U6 Small Nuclear | 
              | U5 Small Nuclear Ribonucleoproteins use Ribonucleoprotein, U5 Small Nuclear | 
              | U5 snRNP use Ribonucleoprotein, U5 Small Nuclear | 
              | U6 Small Nuclear Ribonucleoproteins use Ribonucleoprotein, U4-U6 Small Nuclear | 
              | U6 snRNP use Ribonucleoprotein, U4-U6 Small Nuclear | 
              | U7 Small Nuclear Ribonucleoproteins use Ribonucleoprotein, U7 Small Nuclear | 
              | U7 snRNP use Ribonucleoprotein, U7 Small Nuclear | 
              | U937 Cells | 
              | Ubiquinol-Cytochrome-c Reductase use Electron Transport Complex III | 
              | Ubiquinone | 
              | Ubiquitin | 
              | Ubiquitin C | 
              | Ubiquitin Thiolesterase | 
              | Ubiquitin-Activating Enzymes | 
              | Ubiquitin-Conjugating Enzymes | 
              | Ubiquitin-Like Proteins use Ubiquitins | 
              | Ubiquitin-Protein Ligase use Ubiquitin-Protein Ligases | 
              | Ubiquitin-Protein Ligase Complexes | 
              | Ubiquitin-Protein Ligases | 
              | Ubiquitination | 
              | Ubiquitins | 
              | Uca use Brachyura | 
              | Udder use Mammary Glands, Animal | 
              | UDP use Uridine Diphosphate | 
              | UDP Acetylgalactosamine use Uridine Diphosphate N-Acetylgalactosamine | 
              | UDP Acetylglucosamine use Uridine Diphosphate N-Acetylglucosamine | 
              | UDP Acetylmuramic Acid use Uridine Diphosphate N-Acetylmuramic Acid | 
              | UDP Galactose use Uridine Diphosphate Galactose | 
              | UDP Galactose Acetylglucosamine Galactosyltransferase use N-Acetyllactosamine Synthase | 
              | UDP Galactose Epimerase use UDPglucose 4-Epimerase | 
              | UDP Galactose Pyrophosphorylase use UTP-Hexose-1-Phosphate Uridylyltransferase | 
              | UDP Glucose use Uridine Diphosphate Glucose | 
              | UDP Glucose Dehydrogenase use Uridine Diphosphate Glucose Dehydrogenase | 
              | UDP Glucose Epimerase use UDPglucose 4-Epimerase | 
              | UDP Glucose Pyrophosphorylase use UTP-Glucose-1-Phosphate Uridylyltransferase | 
              | UDP Glucuronic Acid use Uridine Diphosphate Glucuronic Acid | 
              | UDP Glucuronosyltransferase use Glucuronosyltransferase | 
              | UDP Sugars use Uridine Diphosphate Sugars | 
              | UDP Xylose use Uridine Diphosphate Xylose | 
              | UDPG use Uridine Diphosphate Glucose | 
              | UDPG Dehydrogenase use Uridine Diphosphate Glucose Dehydrogenase | 
              | UDPGA use Uridine Diphosphate Glucuronic Acid | 
              | UDPGal use Uridine Diphosphate Galactose | 
              | UDPgalactose 4-Epimerase use UDPglucose 4-Epimerase | 
              | UDPglucose 4-Epimerase | 
              | UDPglucose 4-Epimerase Deficiency Disease use Galactosemias | 
              | UDPglucose-Hexose-1-Phosphate Uridylyltransferase | 
              | UDPglucose-Hexose-1-Phosphate Uridylyltransferase Deficiency use Galactosemias | 
              | UDPGNAc use Uridine Diphosphate N-Acetylglucosamine | 
              | Uganda | 
              | Ukraine | 
              | Ulcer | 
              | Ulcer, Aphthous use Stomatitis, Aphthous | 
              | Ulcer, Rodent use Carcinoma, Basal Cell | 
              | Ulex | 
              | Ulmaceae | 
              | Ulmus | 
              | Ulmus campestris | 
              | Ulna | 
              | Ulna Fractures | 
              | Ulnar Artery | 
              | Ulnar Nerve | 
              | Ulnar Nerve Compression Syndromes | 
              | Ulnar Nerve Diseases use Ulnar Neuropathies | 
              | Ulnar Neuropathies | 
              | Ultimobranchial Body | 
              | Ultracentrifugation | 
              | Ultradeformable Liposomes use Liposomes | 
              | Ultradian Cycles use Activity Cycles | 
              | Ultrafiltration | 
              | Ultrahigh Frequency Waves use Microwaves | 
              | Ultramicrotomy use Microtomy | 
              | Ultrasonic Diagnosis use Ultrasonography | 
              | Ultrasonic Endoscopy use Endosonography | 
              | Ultrasonic Imaging use Ultrasonography | 
              | Ultrasonic Lithotripsy use Lithotripsy | 
              | Ultrasonic Therapy | 
              | Ultrasonics | 
              | Ultrasonography | 
              | Ultrasonography, Color Doppler use Ultrasonography, Doppler, Color | 
              | Ultrasonography, Doppler | 
              | Ultrasonography, Doppler, Color | 
              | Ultrasonography, Doppler, Duplex | 
              | Ultrasonography, Doppler, Pulsed | 
              | Ultrasonography, Doppler, Transcranial | 
              | Ultrasonography, Duplex Doppler use Ultrasonography, Doppler, Duplex | 
              | Ultrasonography, Endoscopic use Endosonography | 
              | Ultrasonography, Fetal use Ultrasonography, Prenatal | 
              | Ultrasonography, Interventional | 
              | Ultrasonography, Intravascular use Ultrasonography, Interventional | 
              | Ultrasonography, Mammary | 
              | Ultrasonography, Prenatal | 
              | Ultrasonography, Pulsed Doppler use Ultrasonography, Doppler, Pulsed | 
              | Ultrasonography, Transcranial Doppler use Ultrasonography, Doppler, Transcranial | 
              | Ultrasound, High-Intensity Focused, Transrectal | 
              | Ultrasound, Interventional use Ultrasonography, Interventional | 
              | Ultraviolet Filters | 
              | Ultraviolet Microscopy use Microscopy, Ultraviolet | 
              | Ultraviolet Rays | 
              | Ultraviolet Spectrophotometry use Spectrophotometry, Ultraviolet | 
              | Ultraviolet Therapy | 
              | Ulva | 
              | Umbelliferae use Apiaceae | 
              | Umbelliferones | 
              | Umbellularia | 
              | Umbilical Arteries | 
              | Umbilical Cord | 
              | Umbilical Cord Blood use Fetal Blood | 
              | Umbilical Cord Blood Stem Cell Transplantation use Cord Blood Stem Cell Transplantation | 
              | Umbilical Cyst use Urachal Cyst | 
              | Umbilical Hernia use Hernia, Umbilical | 
              | Umbilical Veins | 
              | Umbilicus | 
              | Umbra use Umbridae | 
              | Umbrella Filters use Vena Cava Filters | 
              | Umbrella Tree use Araliaceae | 
              | Umbridae | 
              | UMLS use Unified Medical Language System | 
              | UMP use Uridine Monophosphate | 
              | UN use United Nations | 
              | Unaccompanied Child use Unaccompanied Minor | 
              | Unaccompanied Minor | 
              | Unaccounted-For Water | 
              | Unassigned Codon use Codon, Nonsense | 
              | Uncaria | 
              | Uncaria procumbens use Harpagophytum | 
              | Uncaria tomentosa use Cat's Claw | 
              | Uncertainty | 
              | Uncinaria stenocephala use Ancylostomatoidea | 
              | Uncompensated Care | 
              | Unconscious (Psychology) | 
              | Unconscious State use Unconsciousness | 
              | Unconsciousness | 
              | Uncoupling Agents | 
              | Undaria | 
              | Undecylenic Acids | 
              | Under-Developed Countries use Developing Countries | 
              | Underachievement | 
              | Underground Storage use Underground Tanks | 
              | Underground Streams use Groundwater Flow | 
              | Underground Tanks | 
              | Underlying Cause of Death | 
              | Underpopulation use Population Density | 
              | Underregistration | 
              | Understanding use Comprehension | 
              | Undertaking use Mortuary Practice | 
              | UNDP use United Nations Development Programme | 
              | Undulant Fever use Brucellosis | 
              | Unedited Footage | 
              | Unemployment | 
              | UNESCO use United Nations Educational, Scientific and Cultural Organization | 
              | UNICEF use United Nations | 
              | Unicism | 
              | Unified Health System use Single Health System | 
              | Unified Medical Language System | 
              | Uniform Flow | 
              | Unilamellar Liposomes | 
              | Unilateral Hearing Loss use Hearing Loss, Unilateral | 
              | Unio | 
              | Union Lists | 
              | Union of South Africa use South Africa | 
              | Union of Soviet Socialist Republics use USSR | 
              | Unionidae | 
              | Uniparental Disomy | 
              | Uniparental Heterodisomy use Uniparental Disomy | 
              | Uniparental Isodisomy use Uniparental Disomy | 
              | Unipolar Depression use Depressive Disorder | 
              | Uniport use Ion Transport | 
              | Unit Dose Drug Distribution Systems use Medication Systems | 
              | Unit Operations | 
              | Unit Process use Unit Operations | 
              | United Arab Emirates | 
              | United Arab Republic use Egypt | 
              | United Kingdom use Great Britain | 
              | United Nations | 
              | United Nations Development Program use United Nations Development Programme | 
              | United Nations Development Programme | 
              | United Nations Educational, Scientific and Cultural Organization | 
              | United Nations International Children's Emergency Fund use United Nations | 
              | United States | 
              | United States Agency for Health Care Policy and Research use United States Agency for Healthcare Research and Quality | 
              | United States Agency for Healthcare Research and Quality | 
              | United States Agency for International Development | 
              | United States Alcohol, Drug Abuse, and Mental Health Administration use United States Substance Abuse and Mental Health Services Administration | 
              | United States Centers for Disease Control and Prevention use Centers for Disease Control and Prevention (U.S.) | 
              | United States Centers for Medicare and Medicaid Services use Centers for Medicare and Medicaid Services (U.S.) | 
              | United States Department of Agriculture | 
              | United States Department of Health and Human Services use United States Dept. of Health and Human Services | 
              | United States Department of Health, Education, and Welfare use United States Dept. of Health and Human Services | 
              | United States Department of Homeland Security | 
              | United States Department of Veterans Affairs | 
              | United States Dept. of Health and Human Services | 
              | United States Employee Retirement Income Security Act use Employee Retirement Income Security Act | 
              | United States Environmental Protection Agency | 
              | United States Federal Trade Commission | 
              | United States Food and Drug Administration | 
              | United States Gov't Supported, N.I.H. use Research Support, U.S. Gov't, P.H.S. | 
              | United States Gov't Supported, Non-P.H.S. use Research Support, U.S. Gov't, Non-P.H.S. | 
              | United States Gov't Supported, P.H.S. use Research Support, U.S. Gov't, P.H.S. | 
              | United States Government Agencies | 
              | United States Health Care Financing Administration use Centers for Medicare and Medicaid Services (U.S.) | 
              | United States Health Insurance Portability and Accountability Act use Health Insurance Portability and Accountability Act | 
              | United States Health Resources Administration use United States Health Resources and Services Administration | 
              | United States Health Resources and Services Administration | 
              | United States Indian Health Service | 
              | United States National Academy of Sciences use National Academy of Sciences (U.S.) | 
              | United States National Aeronautics and Space Administration | 
              | United States National Center for Health Statistics use National Center for Health Statistics (U.S.) | 
              | United States National Health Insurance use National Health Insurance, United States | 
              | United States National Health Planning Information Center use National Health Planning Information Center (U.S.) | 
              | United States National Institutes of Health use National Institutes of Health (U.S.) | 
              | United States National Library of Medicine use National Library of Medicine (U.S.) | 
              | United States Occupational Safety and Health Administration | 
              | United States Office of Economic Opportunity | 
              | United States Office of National Drug Control Policy | 
              | United States Office of Research Integrity | 
              | United States Office of Technology Assessment | 
              | United States Office of the Assistant Secretary for Health Office of Research Integrity use United States Office of Research Integrity | 
              | United States Patient Self-Determination Act use Patient Self-Determination Act | 
              | United States Public Health Service | 
              | United States Social Security Administration | 
              | United States Substance Abuse and Mental Health Services Administration | 
              | United States Supreme Court use Supreme Court Decisions | 
              | United States Tax Equity and Fiscal Responsibility Act use Tax Equity and Fiscal Responsibility Act | 
              | United States Veterans Administration use United States Department of Veterans Affairs | 
              | United States Visible Human Project use Visible Human Projects | 
              | Unithiol | 
              | Units of Hemotherapy use Hemotherapy Service | 
              | Universal Access To Health Care Services | 
              | Universal Coverage | 
              | Universal Precautions | 
              | Universities | 
              | University Health Services use Student Health Services | 
              | University Medical Centers use Academic Medical Centers | 
              | Unknown Primary Tumors use Neoplasms, Unknown Primary | 
              | Unleaded Gasoline | 
              | Unna-Thost Syndrome use Keratoderma, Palmoplantar, Diffuse | 
              | Unnecessary Procedures | 
              | Unnecessary Surgery use Unnecessary Procedures | 
              | Unpublished Works | 
              | Unsafe Sex | 
              | Unsaturated Dietary Fats use Dietary Fats, Unsaturated | 
              | Unsaturated Fats use Fats, Unsaturated | 
              | Unsaturated Oils use Fats, Unsaturated | 
              | Unstable DNA Sequence use DNA Sequence, Unstable | 
              | Untranslated Regions | 
              | Unux Process Activated Sludges use Pure Oxygen Activated Sludges | 
              | Unventilated Spaces use Confined Spaces | 
              | Unverricht-Lundborg Syndrome | 
              | Up-Regulation | 
              | Upas antiaris | 
              | Upas tieute | 
              | Upflow Anaerobic Reactors | 
              | Upflow Filters | 
              | Upflow Filtration | 
              | Uphill Transport use Biological Transport, Active | 
              | Upper Aerodigestive Tract Neoplasms use Head and Neck Neoplasms | 
              | Upper Airway Resistance Sleep Apnea Syndrome use Sleep Apnea, Obstructive | 
              | Upper Esophageal Sphincter use Esophageal Sphincter, Upper | 
              | Upper Extremity | 
              | Upper Extremity Deformities, Congenital | 
              | Upper Gastrointestinal Tract | 
              | Upper Limb Deformities, Congenital use Upper Extremity Deformities, Congenital | 
              | Upper Respiratory Tract Infections use Respiratory Tract Infections | 
              | Upper Volta use Burkina Faso | 
              | Upregulation use Up-Regulation | 
              | Upstream Stimulatory Factors | 
              | Upwelling | 
              | Urachal Cyst | 
              | Urachus | 
              | Uracil | 
              | Uracil Arabinofuranoside use Arabinofuranosyluracil | 
              | Uracil Arabinoside use Arabinofuranosyluracil | 
              | Uracil Mustard | 
              | Uracil Nucleotides | 
              | Uracil Polynucleotides use Poly U | 
              | Uracil-DNA Glycosidase | 
              | Uralenic Acid use Glycyrrhetinic Acid | 
              | Uramustine use Uracil Mustard | 
              | Uranium | 
              | Uranium (Homeopathy) | 
              | Uranium Compounds | 
              | Uranium Nitricum | 
              | Uranothorium | 
              | Uranus | 
              | Uranyl Nitrate | 
              | Urate Oxidase | 
              | Urbach-Wiethe Disease use Lipoid Proteinosis of Urbach and Wiethe | 
              | Urban Agglomeration use Agglomeration, Urban | 
              | Urban Agriculture | 
              | Urban Agriculture Networks | 
              | Urban Cleaning | 
              | Urban Cleaning Coverage | 
              | Urban Cleaning Enterprises | 
              | Urban Cleaning Equipment | 
              | Urban Cleaning Service | 
              | Urban Development use Urban Renewal | 
              | Urban Fires | 
              | Urban Health | 
              | Urban Health Services | 
              | Urban Horticulture use Urban Agriculture | 
              | Urban Hospitals use Hospitals, Urban | 
              | Urban Planning use City Planning | 
              | Urban Population | 
              | Urban Population Health use Urban Health | 
              | Urban Renewal | 
              | Urban Sanitation | 
              | Urban Settlements | 
              | Urban Villages use Urban Settlements | 
              | Urban Zones | 
              | Urban-Rural Migration use Rural-Urban Migration | 
              | Urbanization | 
              | Urea | 
              | Urea Nitrica | 
              | Urea Pura | 
              | Ureaplasma | 
              | Ureaplasma Infections | 
              | Ureaplasma parvum use Ureaplasma | 
              | Ureaplasma urealyticum | 
              | Urease | 
              | Urecholine use Bethanechol Compounds | 
              | Uremia | 
              | Ureohydrolases | 
              | Ureter | 
              | Ureteral Calculi | 
              | Ureteral Cancer use Ureteral Neoplasms | 
              | Ureteral Diseases | 
              | Ureteral Neoplasms | 
              | Ureteral Obstruction | 
              | Ureterocele | 
              | Ureterolithiasis | 
              | Ureteroscopes | 
              | Ureteroscopic Surgical Procedures use Ureteroscopy | 
              | Ureteroscopy | 
              | Ureterostomy | 
              | Urethane | 
              | Urethra | 
              | Urethral Cancer use Urethral Neoplasms | 
              | Urethral Diseases | 
              | Urethral Neoplasms | 
              | Urethral Obstruction | 
              | Urethral Stenosis use Urethral Stricture | 
              | Urethral Stricture | 
              | Urethritis | 
              | Urgencies use Emergencies | 
              | Urginea | 
              | Urginea scilla use Squilla maritima | 
              | Uric Acid | 
              | Uricase use Urate Oxidase | 
              | Uricosuric Agents | 
              | Uricum Acidum | 
              | Uridine | 
              | Uridine Diphosphate | 
              | Uridine Diphosphate Galactose | 
              | Uridine Diphosphate Glucose | 
              | Uridine Diphosphate Glucose Dehydrogenase | 
              | Uridine Diphosphate Glucose Epimerase use UDPglucose 4-Epimerase | 
              | Uridine Diphosphate Glucuronic Acid | 
              | Uridine Diphosphate N-Acetylgalactosamine | 
              | Uridine Diphosphate N-Acetylglucosamine | 
              | Uridine Diphosphate N-Acetylmuramic Acid | 
              | Uridine Diphosphate Sugars | 
              | Uridine Diphosphate Xylose | 
              | Uridine Diphospho-N-Acetylglucosamine use Uridine Diphosphate N-Acetylglucosamine | 
              | Uridine Diphosphogalactose use Uridine Diphosphate Galactose | 
              | Uridine Diphosphoglucose use Uridine Diphosphate Glucose | 
              | Uridine Diphosphoglucuronic Acid use Uridine Diphosphate Glucuronic Acid | 
              | Uridine Kinase | 
              | Uridine Monophosphate | 
              | Uridine Phosphates use Uracil Nucleotides | 
              | Uridine Phosphorylase | 
              | Uridine Pyrophosphoacetylglucosamine use Uridine Diphosphate N-Acetylglucosamine | 
              | Uridine Pyrophosphogalactose use Uridine Diphosphate Galactose | 
              | Uridine Triphosphate | 
              | Uridyl Transferase use UDPglucose-Hexose-1-Phosphate Uridylyltransferase | 
              | Uridylate 5'-Nucleotidase use 5'-Nucleotidase | 
              | Uridylic Acid use Uridine Monophosphate | 
              | Urinals use Sanitary Devices | 
              | Urinalysis | 
              | Urinary Bladder | 
              | Urinary Bladder Calculi | 
              | Urinary Bladder Diseases | 
              | Urinary Bladder Fistula | 
              | Urinary Bladder Neck Obstruction | 
              | Urinary Bladder Neoplasms | 
              | Urinary Bladder Prolapse use Cystocele | 
              | Urinary Bladder Stones use Urinary Bladder Calculi | 
              | Urinary Bladder, Neurogenic | 
              | Urinary Bladder, Overactive | 
              | Urinary Calculi | 
              | Urinary Catheterization | 
              | Urinary Diversion | 
              | Urinary Fistula | 
              | Urinary Incontinence | 
              | Urinary Incontinence, Stress | 
              | Urinary Incontinence, Urge | 
              | Urinary Kallikrein use Tissue Kallikreins | 
              | Urinary Plasminogen Activator use Urokinase-Type Plasminogen Activator | 
              | Urinary Reservoirs, Continent | 
              | Urinary Retention | 
              | Urinary Sphincter, Artificial | 
              | Urinary Stones use Urinary Calculi | 
              | Urinary Tract | 
              | Urinary Tract Cancer use Urologic Neoplasms | 
              | Urinary Tract Diseases use Urologic Diseases | 
              | Urinary Tract Infections | 
              | Urinary Tract Physiological Phenomena | 
              | Urinary Tract Physiological Processes | 
              | Urinary Tract Physiology use Urinary Tract Physiological Phenomena | 
              | Urination | 
              | Urination Disorders | 
              | Urine | 
              | Urine Concentrating Ability use Kidney Concentrating Ability | 
              | Urinoma | 
              | Urobilin | 
              | Urobilinogen | 
              | Urocanase use Urocanate Hydratase | 
              | Urocanate Hydratase | 
              | Urocanic Acid | 
              | Urochordata | 
              | Urocortin use Urocortins | 
              | Urocortins | 
              | Urocyon use Foxes | 
              | Urodela | 
              | Urodynamics | 
              | Urofollitropin | 
              | Urogastrone use Epidermal Growth Factor | 
              | Urogastrone Receptor use Receptor, Epidermal Growth Factor | 
              | Urogenital Abnormalities | 
              | Urogenital Cancer use Urogenital Neoplasms | 
              | Urogenital Neoplasms | 
              | Urogenital Surgical Procedures | 
              | Urogenital System | 
              | Urography | 
              | Urokinase use Urokinase-Type Plasminogen Activator | 
              | Urokinase-Type Plasminogen Activator | 
              | Urolithiasis | 
              | Urologic Cancer use Urologic Neoplasms | 
              | Urologic Diseases | 
              | Urologic Neoplasms | 
              | Urologic Surgical Procedures | 
              | Urologic Surgical Procedures, Male | 
              | Urological Manifestations | 
              | Urology | 
              | Urology Department, Hospital | 
              | Uronic Acids | 
              | Uropepsinogen use Pepsinogen A | 
              | Uroporphyrinogen Carboxy-Lyase use Uroporphyrinogen Decarboxylase | 
              | Uroporphyrinogen Decarboxylase | 
              | Uroporphyrinogen I Synthase use Hydroxymethylbilane Synthase | 
              | Uroporphyrinogen III Cosynthetase use Uroporphyrinogen III Synthetase | 
              | Uroporphyrinogen III Synthetase | 
              | Uroporphyrinogen Isomerase use Uroporphyrinogen III Synthetase | 
              | Uroporphyrinogen-III Synthase use Uroporphyrinogen III Synthetase | 
              | Uroporphyrinogens | 
              | Uroporphyrins | 
              | Urotensins | 
              | Urothelium | 
              | Ursidae | 
              | Ursodeoxycholic Acid | 
              | Ursus use Ursidae | 
              | Urtica crenulata | 
              | Urtica dioica | 
              | Urtica gigas | 
              | Urtica urens | 
              | Urticaceae | 
              | Urticaria | 
              | Urticaria Pigmentosa | 
              | Urticaria, Giant use Angioedema | 
              | Uruguay | 
              | Urundi use Burundi | 
              | US Agency for International Development use United States Agency for International Development | 
              | US AID use United States Agency for International Development | 
              | USAID use United States Agency for International Development | 
              | USDA use United States Department of Agriculture | 
              | Use of Radiation in Medicine and Investigation | 
              | Use of Radiation on Energy | 
              | Use of Radiation on Industry | 
              | Use of Scientific Information for Health Decision Making | 
              | Used Oils use Lubricant Oils | 
              | Used Rubber Tires use Tires | 
              | Used Tires use Tires | 
              | User Embracement | 
              | User-Computer Interface | 
              | Uses of Epidemiology | 
              | Uses of Radiation | 
              | USFDA use United States Food and Drug Administration | 
              | USFTC use United States Federal Trade Commission | 
              | Usher Syndromes | 
              | Usnea | 
              | Usnea barbata use Usnea | 
              | Usnea Barbata (Homeopathy) | 
              | USPHS use United States Public Health Service | 
              | USSR | 
              | Ustilaginales | 
              | Ustilago | 
              | Ustilago maydis | 
              | Utah | 
              | Uterine Appendages use Adnexa Uteri | 
              | Uterine Artery Embolization | 
              | Uterine Cancer use Uterine Neoplasms | 
              | Uterine Cervical Diseases | 
              | Uterine Cervical Dysplasia | 
              | Uterine Cervical Erosion | 
              | Uterine Cervical Incompetence | 
              | Uterine Cervical Neoplasms | 
              | Uterine Cervicitis | 
              | Uterine Contraction | 
              | Uterine Diseases | 
              | Uterine Endoscopy use Hysteroscopy | 
              | Uterine Hemorrhage | 
              | Uterine Inertia | 
              | Uterine Inversion | 
              | Uterine Monitoring | 
              | Uterine Muscle use Myometrium | 
              | Uterine Neoplasms | 
              | Uterine Perforation | 
              | Uterine Prolapse | 
              | Uterine Rupture | 
              | Uterine Stimulants use Oxytocics | 
              | Uteroglobin | 
              | Uteroplacental Circulation use Placental Circulation | 
              | Uteroscopes use Hysteroscopes | 
              | Uteroverdine use Biliverdine | 
              | Uterus | 
              | Utility Failure use Interruption of Services Supply | 
              | Utilization and Quality Control Peer Review Organizations use Professional Review Organizations | 
              | Utilization Review | 
              | Utilization Review, Drug use Drug Utilization Review | 
              | Utopias | 
              | UTP use Uridine Triphosphate | 
              | UTP-Glucose-1-Phosphate Uridylyltransferase | 
              | UTP-Hexose-1-Phosphate Uridylyltransferase | 
              | Utricle use Saccule and Utricle | 
              | Utrophin | 
              | UTRs use Untranslated Regions | 
              | Uukuniemi Group Viruses use Uukuniemi virus | 
              | Uukuniemi virus | 
              | Uva ursi (Homeopathy) | 
              | Uva-ursi use Arctostaphylos | 
              | Uvaria | 
              | Uvaria triloba | 
              | Uvea | 
              | Uveal Diseases | 
              | Uveal Neoplasms | 
              | Uveitis | 
              | Uveitis, Anterior | 
              | Uveitis, Intermediate | 
              | Uveitis, Posterior | 
              | Uveitis, Suppurative | 
              | Uveitis, Sympathetic use Ophthalmia, Sympathetic | 
              | Uveomeningoencephalitic Syndrome | 
              | Uveomeningoencephalitis use Uveomeningoencephalitic Syndrome | 
              | Uveoparotid Fever | 
              | Uveoparotitis use Uveoparotid Fever | 
              | Uvomorulin use Cadherins | 
              | Uvula | 
              | Uzara | 
              | Uzbek S.S.R. use Uzbekistan | 
              | Uzbekistan |