Copy of `Dorland's Medical Dictionary`

The wordlist doesn't exist anymore, or, the website doesn't exist anymore. On this page you can find a copy of the original information. The information may have been taken offline because it is outdated.

Dorland's Medical Dictionary Category: Health and Medicine > Medical Dictionary Date & country: 31/12/2010, USA Words: 39128

uniocular
(u″ne-ok´u-lәr) monocular.

union
(ūn´yәn) the growing together of tissues separated by injury, as of the ends of a fractured bone, or of the edges of a wound; see also healing.

uniovular
(u″ne-ov´u-lәr) monovular, monozygotic.

unipara
(u-nip´ә-rә) primipara.

uniparental
(u″nĭ-pә-ren´tәl) pertaining to one of the parents only.

uniparous
(u-nip´ә-rәs) producing only one offspring or egg at one time. primiparous; see primipara.

unipennate muscle
semipennate muscle.

unipolar
(u″nĭ-po´lәr) having but a single pole or process, as a nerve cell. pertaining to mood disorders in which only depressive episodes occur.

unipolar depression
a type that is not accompanied by episodes of mania or hypomania, such as major depressive disorder or dysthymic disorder. The term is sometimes used more specifically as a synonym of major depressive disorder.

unipolar disorders
depressive disorders.

unipolar lead
a configuration of two electrodes, an active or therapeutic electrode in contact with the organ being stimulated and the other (the reference or indifferent electrode) at a distant site, usually the surface of the pulse generator.

unipolar limb lead
any unipolar array in which the exploring electrode is placed on a limb.

unipolar neuron
a neuron that has just one process.

unipolar pacemaker
an implanted pacemaker in which the lead has a single stimulating electrode, the cathode, with the anode connected to an indifferent electrode, usually the outer surface of the pulse generator.

unipotency
(u″nĭ-po´tәn-se) the ability of a part to develop in one manner only, or of a cell to develop into only one type of cell. adj., unip´otent, unipoten´tial., adj.

unique DNA
single copy DNA.

unisexual
(u″nĭ-sek´shoo-әl) pertaining to only one sex. having the sexual organs of one sex only.

unit
(u´nit) a single thing; one segment of a whole that is made up of identical or similar segments. a specifically defined amount of anything subject to measurement, as of activity, dimension, velocity, volume, or the like. a distinct part of a hospital, usually having a specific physical location and...

unit membrane
the trilaminar structure of all cellular membranes (such as the plasma membrane, nuclear membranes, mitochondrial membranes, endoplasmic reticulum, lysosomes) as they appear in electron micrographs. The biochemical structure is a lipid bilayer.

unitary
(u´nĭ-tar″e) pertaining to a single object or individual.

United States Adopted Name
(USAN) a nonproprietary designation for any compound used as a drug, established by negotiation between the manufacturer of the compound and a nomenclature committee known as the USAN Council, which is sponsored jointly by the American Medical Association, the American Pharmaceutical Association, and The Uni...

United States Pharmacopeia
(USP) a legally recognized compendium of standards for drugs, published by The United States Pharmacopeial Convention, Inc., and revised periodically. It includes also assays and tests for the determination of strength, quality, and purity.

United States Public Health Service
(USPHS) a governmental health agency that is part of the United States Department of Health and Human Services; see also public health.

uniterminal
(u″nĭ-tur´mĭ-nәl) a monopolar apparatus.

univalent
(u″nĭ-va´lәnt) having a valence of one.

universal alopecia
alopecia universalis.

universal donor
a person whose blood is type O in the ABO blood group system; such blood is sometimes used in emergency transfusion. Transfusion of blood cells rather than whole blood is preferred.

Universal Numbering System
a tooth numbering system that numbers the permanent teeth from 1 (maxillary right third molar) through 32 (mandibular right third molar), working leftward across the maxilla, dropping to the mandible and working back rightward; the primary teeth are dented similarly, using the letters A through T.

universal pacemaker
a term sometimes used to describe a DDD pacemaker, emphasizing that because it can be programmed to operate in one of numerous possible pacemaker modes under specific circumstances, it can be made to most closely approximate normal electrophysiologic functioning under a variety of conditions.

universal precautions
a group of measures formerly recommended for protection of noninfected individuals against bloodborne infections such as hepatitis B virus and human immunodeficiency virus, now replaced by the measures called standard precautions.

unmyelinated
(әn-mi´ә-lĭ-nāt″әd) not having a myelin sheath.

unmyelinated fibers
nerve fibers that lack a myelin sheath; these are abundant in the autonomic nervous system and constitute the gray matter of the central nervous system.

unmyelinated nerve
a nerve whose fibers (axons) are not encased in a myelin sheath.

unoprostone
(u″no-pros´tōn) an antiglaucoma agent that decreases elevated intraocular pressure by increasing the outflow of aqueous humor; used as unoprostone isopropyl in the treatment of open-angle glaucoma and ocular hypertension, applied topically to the conjunctiva.

unphysiologic
(un″fiz-e-o-loj´ik) not in harmony with the laws of physiology.

unresolved pneumonia
pneumonia in which the lung signs fail to clear up within the usual period.

unsaturated
(әn-sach´ә-rāt″әd) not having all affinities of its elements satisfied (unsaturated compound). not holding all of a solute that can be held in solution by the solvent (unsaturated solution). denoting compounds in which two or more atoms are united by double or triple bo...

unsaturated fat
a fat containing unsaturated fatty acids.

unsaturated fatty acid
a fatty acid that contains one or more double bond(s); those with one double bond are called monounsaturated fatty acids, and those with several are called polyunsaturated fatty acids.

Unschuld sign
a nonspecific early sign of diabetes mellitus: a tendency to cramping in the calves.

unstable angina
chest pain of cardiac origin that is variable, usually increasing in frequency and intensity and with irregular timing.

unstriated
(әn-stri´āt-әd) having no striations, as smooth muscle.

Unverricht disease
(oon´fer-ikt) Unverricht-Lundborg disease myoclonic epilepsy.

upper airway
the airway from the nares and lips to the larynx.

upper airway resistance syndrome
an incomplete form of obstructive sleep apnea in which the upper airway resists air flow and becomes partially obstructed during sleep.

upper brachial plexus paralysis
paralysis of arm muscles due to destruction of the fifth and sixth cervical roots (upper trunk of the brachial plexus); small hand muscles are unaffected. When due to birth trauma it is called Erb-Duchenne paralysis.

upper limb
the limb of the body extending from the deltoid region to the hand; it is specialized for functions requiring great mobility, such as grasping and manipulating. See also arm.

UPPP
uvulopalatopharyngoplasty.

Uppsala virus
U virus.

upregulation
(up″reg-u-la´shәn) increase in expression of a gene; in the narrowest sense, that in which transcription of a specific mRNA is increased, but also used more broadly to refer to increase in mRNA levels for a particular gene from any cause, such as increased stability of the specific mRNA.

upstream
(up´strēm) in molecular biology, a term used to denote a region of nucleic acid to the 5´ side of a gene or region of interest.

uptake
(up´tāk) absorption and incorporation of a substance by living tissue. biologic uptake movement of hazardous substances from the environment into the tissues of plants or animals. radioactive iodine uptake , radioiodine uptake uptake o...

urachal fossa
one on the inner abdominal wall, between the urachus and the hypogastric artery.

urachus
(u´rә-kәs) a fetal canal connecting the bladder with the allantois, persisting throughout life as a cord (median umbilical ligament). adj., u´rachal., adj. patent urachus a condition in which the urachus remains a hollow tube connecting the bladder and the umbil...

uracil
(ūr´ә-sil) a pyrimidine base found in RNA (ribonucleic acid).

uracil test
see Wheeler and Johnson test.

uranium
(U) (u-ra´ne-әm) a hard and heavy radioactive metallic element; atomic number, 92; atomic weight, 238.03; see Appencix 6. Naturally occurring uranium is composed of three isotopes of mass numbers 234, 235, and 238. Uranium 235 separated from U 238 undergoes fission with slow neutrons, giving...

uranyl
(u´rә-nәl) the UO2++ ion, as in uranyl sulfate.

urarthritis
(u″rahr-thri´tis) gouty arthritis.

urate
(ūr´āt) any salt or anion of uric acid.

urate calculus
uric acid calculus.

urate nephropathy
uric acid nephropathy any of a group of kidney diseases occurring in patients with hyperuricemia, including an acute form, a chronic form (gouty nephropathy), and nephrolithiasis with formation of uric acid calculi.

uratemia
(u″rә-te´me-ә) urates in the blood.

uratic
(u-rat´ik) pertaining to urates or to gout.

uratic degeneration
degeneration marked by the deposit of urates or uric acid.

uratoma
(u″rә-to´mә) a concretion made up of urates; tophus.

uratosis
(u″rә-to´sis) the deposit of urates in the tissues.

uraturia
(u″rә-tu´re-ә) hyperuricosuria.

Urbach-Wiethe disease
(ur´bak ve´tә) lipid proteinosis.

urban yellow fever
see yellow fever.

urceiform
(әr-se´ĭ-form) pitcher-shaped.

urea
(u-re´ә) a substance found in urine, blood, and lymph, the chief nitrogenous constituent of urine, and the primary nitrogenous end-product of protein metabolism; it is formed in the liver from amino acids or ammonia compounds. The amount of urea in the urine increases both as tissues undergo disintegration and repair, a...

urea breath test
a breath test for the presence of Helicobacter pylori in the stomach: the patient is given an oral dose of urea labeled with carbon 13 (heavy carbon) or carbon 14 (radioactive carbon). At fixed time intervals the breath is analyzed for presence of labeled carbon dioxide. Excessive levels of carbon dioxide indicate presence of H...

urea clearance
the volume of the blood cleared of urea per minute by either renal clearance or hemodialysis. Called also blood-urea clearance.

urea excretion ratio
the ratio between the amount of urea in the urine excreted in one hour and the amount in 100 mL of blood; the normal ratio is 50.

urea nitrogen
the urea concentration of serum or plasma, conventionally specified in terms of nitrogen content and called blood urea nitrogen (BUN), an important indicator of renal function.

urea test
see specific tests, including diacetyl test, Schroeder test, and urease test (def. 1).

ureagenesis
(u-re″ә-jen´ә-sis) formation of urea; called also ureapoiesis. adj., ureagenet´ic., adj.

Ureaplasma
(u-re″ә-plaz´mә) a genus of gram-negative, nonmotile, pleomorphic bacteria that lack a cell wall and form small granular colonies. U. urealy´ticum is a common inhabitant of the genitourinary tract and is associated with sexually transmitted nongonococcal urethritis.

ureapoiesis
(u-re″ә-poi-e´sis) ureagenesis. adj., ureapoiet´ic., adj.

urease
(u´re-ās) an enzyme that catalyzes the decomposition of urea to ammonia and carbon dioxide.

urease test
a test for urea based on the conversion of urea into ammonium carbonate by the urease of soybean. (for the production of urease by bacteria) urease test broth is prepared in slants. After inoculation of the surface and incubation, urease-positive cultures produce an alkaline reaction (red color) in the medium. Pro...

Urecholine supersensitivity test
(for neurogenic bladder) 2.5 mg of bethanechol (Urecholine) is administered subcutaneously; the bladder is neurogenic if it exhibits a rise in intravesical pressure more than 15 cm greater than that of a control.

uredema
(u″rĕ-de´mah) swelling from extravasated urine.

uremia
(u-re´me-ә) an excess in the blood of urea, creatinine, and other nitrogenous end products of protein and amino acid metabolism; more correctly referred to as azotemia. in current usage, the entire complex of signs and symptoms of chronic renal failure. As the glomerular filtration rate falls, serum urea a...

uremic bone disease
renal osteodystrophy.

uremic pericarditis
pericarditis occurring as a complication of uremia; it is characterized by shaggy, vascular, fibrinous exudate on the surfaces of the pericardium.

uremic pleuritis
pleurisy, usually of the fibrinous type, with pleural effusion in patients with uremia, often accompanying uremic pericarditis.

uremic seizure
one due to uremia, or retention in the blood of material that should have been expelled by the kidneys.

uremic syndrome
the spectrum of symptoms accompanying uremia; see uremia (def. 2).

uremigenic
(u-re″mĭ-jen´ik) caused by uremia. causing uremia.

ureotelic
(u″re-o-tel´ik) having urea as the chief excretory product of nitrogen metabolism.

ureter
(u-re´tәr) (u´rә-tәr) the fibromuscular tube, 41 to 46 cm long, through which the urine passes from the kidney to the bladder. As urine is produced by each kidney, it passes into the ureter, which, by contracting rhythmically, forces the urine along and empties it in spurts into the bl...

ureteral catheter
a long, small gauge catheter designed for insertion directly into a ureter, either through the urethra and bladder or posteriorly via the kidney.

ureteral meatus
ureteral orifice.

ureteral neuromuscular dysplasia
megaureter.

ureteral orifice
the opening of a ureter into the urinary bladder at one corner of the trigone of the bladder. Called also ureteral meatus.

ureteralgia
(u-re″tәr-al´jә) pain in the ureter.

ureterectasis
(u-re″tәr-ek´tә-sis) distention of the ureter, such as in megaureter or hydroureter.

ureterectomy
(u-re″tәr-ek´tә-me) excision of a ureter.