| ur-defenses | Fundamental beliefs essential for human psychological integrity; e.g., religion, science. Origin: Ger. Ur-, primitive, earliest, + defenses (05 Mar 2000) |
|---|---|
| Ura | <abbreviation> Uracil. (05 Mar 2000) |
| urachal | Relating to the urachus. (05 Mar 2000) |
| urachal cyst | Cyst occurring in a persistent portion of the urachus, presenting as an extraperitoneal mass in the umbilical region. It is characterised by abdominal pain, and fever if infected. It may rupture, leading to peritonitis, or it may drain through the umbilicus. (12 Dec 1998) |
| urachal fistula | A fistula connecting the urachus with a hollow organ. (05 Mar 2000) |
| urachal fold | A fold of peritoneum on the anterior wall of the abdomen covering the urachus, or remains of the allantoic stalk. Synonym: plica umbilicalis mediana, middle umbilical fold, plica umbilicalis media, plica urachi, urachal fold. (05 Mar 2000) |
| urachal ligament | <anatomy> The remnant of the urachus, contained in the median umbilical fold; it persists as a midline fibrous cord between the apex of the bladder and the umbilicus. Synonym: ligamentum umbilicale medianum, middle umbilical ligament, urachal ligament. (05 Mar 2000) |
| urachus | <anatomy> A cord or band of fibrous tissue extending from the bladder to the umbilicus. Origin: NL, fr. Gr. Urine + to hold. Source: Websters Dictionary (01 Mar 1998) |
| uracil | <biochemistry> The pyrimidine base from which uridine is derived. (18 Nov 1997) |
| uracil dehydrogenase | An oxidoreductase catalyzing oxidation of uracil to barbituric acid; also oxidises thymine. Synonym: uracil oxidase. (05 Mar 2000) |
| uracil mustard | <chemical> Nitrogen mustard derivative of uracil. It is a alkylating antineoplastic agent that is used in lymphatic malignancies, and causes mainly gastrointestinal and bone marrow damage. Pharmacological action: antineoplastic agent, alkylating. Chemical name: 2,4(1H,3H)-Pyrimidinedione, 5-(bis(2-chloroethyl)amino)- (12 Dec 1998) |
| uracil oxidase | An oxidoreductase catalyzing oxidation of uracil to barbituric acid; also oxidises thymine. Synonym: uracil oxidase. (05 Mar 2000) |
| uracil permease | <chemical> Mediates uptake of uracil in eucaryotic organisms; does not transport other natural pyrimidines such as cytosine, thymine or uridine Chemical name: permease, uracil Synonym: n 137 (26 Jun 1999) |
| uracil phosphoribosyltransferase | See: phosphoribosyltransferase. (05 Mar 2000) |
| uracil-6-carboxylic acid | Intermediate in the de novo synthesis of pyrimidines. Linked glycosidically to ribose 5' phosphate, orotate forms the pyrimidine nucleotide orotidylate, that on decarboxylation at position 5 of the pyrimidine ring yields the major nucleotide uridylate (uridine 5' phosphate). (18 Nov 1997) |