| gene duplication | <molecular biology> A class of DNA rearrangement that generates a supernumerary copy of a gene in the genome. This would allow each gene to evolve independently to produce distinct functions. Such a set of evolutionarily related genes can be called a gene family. (18 Nov 1997) |
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| duplication | 1. The act of duplicating, or the state of being duplicated; a doubling; a folding over; a fold. 2. <biology> The act or process of dividing by natural growth or spontaneous action; as, the duplication of cartilage cells. <mathematics> Duplication of the cube, the operation of finding a cube having a volume which is double that of a given cube. Origin: L. Duplicatio: cf. F. Duplication. Source: Websters Dictionary (01 Mar 1998) |
| duplication cyst | A congenital cystic malformation attached to or originating from any part of the alimentary canal, from the base of the tongue to the anus, which reproduces the structure of the adjacent alimentary tract. (05 Mar 2000) |
| duplication of chromosomes | A chromosome aberration resulting from unequal crossing over or exchange of segments between two homologous chromosomes; one chromosome of the pair loses a small segment, while the other gains this segment; the chromosome gaining the segment has undergone duplication while its homologue has undergone deletion. See: haemoglobin Lepore. (05 Mar 2000) |
| acute urethral syndrome | <syndrome> This describes a clinical syndrome of dysuria (pain on urination) with sterile or low bacterial colony count culture results. Many of these patients have early or low-grade E. Coli, Staphylococcal saprophyticus or Chlamydia trachomatis infections. All are treated with antibiotics. (27 Sep 1997) |
| anterior urethral valve | A crescentic horizontal fold in the proximal spongy urethra. (05 Mar 2000) |
| posterior urethral valves | Anomalous folds occurring at the level of the seminal colliculus. Synonym: Amussat's valvula. (05 Mar 2000) |
| preprostate urethral sphincter | The complete collar of smooth muscle cells of the neck of the urinary bladder which extend distally to surround the preprostatic sportion of the male urethra. There is not a comparable structure in the neck of the femoral bladder; the internal urethral sphincter may exist to prevent reflux of semen into bladder. Synonym: annulus urethralis, internal urethral sphincter, musculus sphincter vesicae, preprostate urethral sphincter, proximal urethral sphincter, sphincter muscle of urinary bladder. (05 Mar 2000) |
| proximal urethral sphincter | The complete collar of smooth muscle cells of the neck of the urinary bladder which extend distally to surround the preprostatic sportion of the male urethra. There is not a comparable structure in the neck of the femoral bladder; the internal urethral sphincter may exist to prevent reflux of semen into bladder. Synonym: annulus urethralis, internal urethral sphincter, musculus sphincter vesicae, preprostate urethral sphincter, proximal urethral sphincter, sphincter muscle of urinary bladder. (05 Mar 2000) |
| internal urethral opening | The internal opening or orifice of the urethra, at the anterior and inferior angle of the trigone. Synonym: ostium urethrae internum, internal urethral opening. (05 Mar 2000) |
| internal urethral orifice | The internal opening or orifice of the urethra, at the anterior and inferior angle of the trigone. Synonym: ostium urethrae internum, internal urethral opening. (05 Mar 2000) |
| internal urethral sphincter | The complete collar of smooth muscle cells of the neck of the urinary bladder which extend distally to surround the preprostatic sportion of the male urethra. There is not a comparable structure in the neck of the femoral bladder; the internal urethral sphincter may exist to prevent reflux of semen into bladder. Synonym: annulus urethralis, internal urethral sphincter, musculus sphincter vesicae, preprostate urethral sphincter, proximal urethral sphincter, sphincter muscle of urinary bladder. (05 Mar 2000) |
| external urethral orifice | The slitlike opening of the urethra in the glans penis, the external orifice of the urethra (in the female) in the vestibule, usually upon a slight elevation, the papilla urethrae. Synonym: ostium urethrae externum, external opening of urethra, meatus urinarius, orificium urethrae externum. (05 Mar 2000) |
| external urethral sphincter | Origin, ramus of pubis; insertion, with fellow in median raphe behind and in front of urethra; action, constricts membranous urethra; nerve supply, pudendal. Synonym: musculus sphincter urethrae, external urethral sphincter, Guthrie's muscle, musculus compressor urethrae, musculus constrictor urethrae, musculus sphincter urethrae membranaceae, sphincter muscle of urethra, Wilson's muscle. (05 Mar 2000) |
| female 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) |