| urethral plate | An endodermal plate located ventromedially in the developing genital tubercle of a young embryo; it later opens to form the lining of the penile urethra. (05 Mar 2000) |
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| urethral pressure profile | The continual recording of pressure through a hole in the side of a small catheter as it is pulled (at a constant rate while either water or a gas is infused through the hole) from a point within the bladder, through the vesical neck, and down the entire urethra; a form of resistance measurement which gives a tracing indicative of the functional length of the urethra and the points of maximal urethral resistance. (05 Mar 2000) |
| urethral stricture | <urology> A narrowing of the urethra that results from inflammation, injury or infection. (27 Sep 1997) |
| urethral surface of penis | The surface of the penis opposite to the dorsum penis. Synonym: facies urethralis penis. (05 Mar 2000) |
| urethral syndrome | <syndrome, urology> Symptoms of a urinary tract infection although the urine is sterile when analysed. This suggests the infection is localised to the urethra (urethritis). Treated with antibiotics. (27 Sep 1997) |
| urethral valves | Folds in the urethral mucous membrane. See: anterior urethral valve, posterior urethral valves. (05 Mar 2000) |
| abdominal ring | The opening in the transversalis fascia through which the ductus deferens (or round ligament in the female) and gonadal vessels enter the inguinal canal. Located midway between anterior superior iliac spine and pubic tubercle, it is bounded medially by the lateral umbilical ligament (inferior epigastric vessels) and inferiorly by the inguinal ligament. Indirect inguinal hernias exit the abdominal cavity via the deep inguinal ring Synonym: annulus inguinalis profundus, abdominal ring, annulus abdominalis, internal inguinal ring. (05 Mar 2000) |
| amnion ring | The ring formed by the attachment of the amnion to the umbilical cord at its point of emergence from the umbilicus. (05 Mar 2000) |
| annuloplasty ring | The dilated annulus is sutured, often to a prosthetic ring, thereby reducing it to its normal systolic size. (05 Mar 2000) |
| anterior limiting ring | The periphery of the cornea marking the termination of Descemet's membrane and the anterior border of the trabecular meshwork; an important landmark in gonioscopy. Synonym: Schwalbe's ring. (05 Mar 2000) |
| Balbani ring | An extremely large puff at a band of a polytene chromosome. (05 Mar 2000) |
| Balbiani ring | <cell biology, genetics> The largest puffs seen on the polytene chromosomes of Diptera are called Balbiani rings after the nineteenth century microscopist who first described polytene chromosomes. (18 Nov 1997) |
| Bandl's ring | A constriction located at the junction of the thinned lower uterine segment with the thick retracted upper uterine segment, resulting from obstructed labour; this is one of the classic signs of threatened rupture of the uterus. Synonym: Bandl's ring, Baudelocque's uterine circle, Scanzoni's second os. (05 Mar 2000) |
| benzene ring | The closed-chain arrangement of the carbon and hydrogen atoms in the benzene molecule. See: cyclic compound. (05 Mar 2000) |
| Bickel's ring | The broken ring of lymphoid tissue, formed of the lingual, faucial, and pharyngeal tonsils. Synonym: Bickel's ring, tonsillar ring, Waldeyer's throat ring. (05 Mar 2000) |