| citric acid | <biochemistry> An important intermediate in the citric acid cycle which breaks down glucose into water and carbon dioxide when oxygen is present. The acid contains three carboxyl groups, has the chemical formula of C6H8O7, and is found in citrus fruits (oranges, grapefruit, lemons, etc.). It is used as an antioxidant and as artificial flavouring in commercially-processed foods. (09 Oct 1997) |
|---|---|
| citric acid cycle | <biochemistry> The central feaure of oxidative metabolism. Cyclic reactions whereby acetyl CoA is oxidized to carbon dioxide providing reducing equivalents (NADH or FADH2) to power the electron transport chain. Also provides intermediates for biosynthetic processes. (16 Dec 1997) |
| citric acid urine test | <investigation> A test which measures the amount of citric acid in the urine. This test is used to diagnose renal tubular acidosis and evaluate those with kidney stones. A below normal level of citric acid in the urine can indicate renal tubular acidosis. Urine citric acid levels can be increased in those with have a high carbohydrate diet, are on oestrogen therapy or vitamin D therapy. (27 Sep 1997) |
| anhydrous | <chemistry> A substance deprived or destitute of water. (12 Nov 1997) |
| anhydrous alcohol | Water having been removed. Synonym: anhydrous alcohol. (05 Mar 2000) |
| anhydrous chloral | CCl3-CHO; trichloroacetaldehyde;a thin oily liquid with a pungent odour, formed by the action of chlorine gas on alcohol. Synonym: anhydrous chloral. (05 Mar 2000) |
| anhydrous lanolin | Lanolin that contains not more than 0.25% of water; used as a water-adsorbable ointment base. (05 Mar 2000) |
| Rambourg's chromic acid-phosphotungstic acid stain | <technique> A stain for glycoproteins, used with an electron microscope, with which ultrathin tissue sections reveal complex carbohydrates in the same locations as shown by Rambourg's periodic acid-chromic methenamine-silver stain. (05 Mar 2000) |
| a1-acid glycoprotein | <biology> Plasma protein of mammals and birds, 38% carbohydrate. In humans a single chain glycoprotein of 39 kD. Increased levels are associated with inflammation, pregnancy and various diseases. (18 Nov 1997) |
| abscisic acid | <biochemistry> A lipid hormone that inhibits cell growth in plants, it is associated with fruit drop, leaf death and seed dormancy. It is synthesised in the plastids from carotenoids. This hormone helps plants deal with water loss, and its effects can be reversed with gibberellins. (06 May 1997) |
| abscisic acid 8'-hydroxylase | <enzyme> Catalyses conversion of abscisic acid to 8'-hydroxyabscisic acid, which rearranges to phaseic acid Registry number: EC 1.14.99.- Synonym: aba 8'-hydroxylase (26 Jun 1999) |
| acetic acid | <chemical> The acid most commonly associated with vinegar, it is the most commercially important organic acid and is used to manufacture a wide range of chemical products, such as plastics and Acetobacter but, except for making vinegar, is usually made through synthetic processes. Derivatives of acetic acid which may be formed by substitution reactions. Mono- and di-substituted, as well as, halogenated compounds have been synthesised. Experimentally, alpha- and n2- substituted acetic acids have been examined for their anti-inflammatory activity and effect on the central nervous system respectively. Additionally, limited exposure data has been collected on dibromo and dichloroacetic acids to determine whether they pose health effects. Synonym: ethanoic acid. (26 Jun 1999) |
| acetoacetic acid | CH3COCH2COOH;one of the ketone bodies, formed in excess and appearing in the urine in starvation or diabetes. Synonym: diacetic acid. (05 Mar 2000) |
| acetohydroxamic acid | C2H5NO2; N-Hydroxyacetamide;an inhibitor of urease, used as adjunctive therapy in chronic urea-splitting urinary infections. (05 Mar 2000) |
| acetrizoic acid | <chemical> A water-soluble, iodinated radiographic contrast medium, used as sodium acetrizoate in hysterosalpingography. Pharmacological action: contrast media. Chemical name: Benzoic acid, 3-(acetylamino)-2,4,6-triiodo- (12 Dec 1998) |