| Xaa | Symbol for unspecified amino acid. (05 Mar 2000) |
|---|---|
| xamoterol | <chemical> A selective beta-1-adrenergic partial agonist. Because it is a partial agonist it acts like an agonist when sympathetic activity is low and as an antagonist when sympathetic activity is high. It reduces myocardial ischemia and improves ventricular function in patients with mild to moderate heart failure. In patients with severe heart failure it has been shown to produce benefits in systolic and diastolic function. Pharmacological action: adrenergic beta-agonists, cardiotonic agent, sympathomimetic. Chemical name: 4-Morpholinecarboxamide, N-(2-((2-hydroxy-3-(4-hydroxyphenoxy)propyl)amino)ethyl)-, (+-)- (12 Dec 1998) |
| Xan | <abbreviation> Xanthine. (05 Mar 2000) |
| xanchromatic | Yellow-coloured. Synonym: xanchromatic, xanthochromic. (05 Mar 2000) |
| xanthamide | <chemistry> An amido derivative of xanthic acid obtained as a white crystalline substance, C2H5O.CS.NH2. Synonym: xanthogen amide. Origin: Xanthic + amide. Source: Websters Dictionary (01 Mar 1998) |
| xanthan gum | <chemical> A polysaccharide gum often used in foods, it is synthesised (fermented) from glucose by the bacterium Xanthomonas campestris. (11 May 1997) |
| xanthate | <chemistry> A salt of xanthic; a xanthogenate. See: Xanthic. Source: Websters Dictionary (01 Mar 1998) |
| xanthelasma | <medicine> See Xanthoma. Origin: NL.; Gr. Xanqos = yellow + 'elasma a metal plate. Source: Websters Dictionary (01 Mar 1998) |
| xanthelasma palpebrarum | Soft yellow-orange plaques on the eyelids or medial canthus, the most common form of xanthoma; may be associated with low-density lipoproteins, especially in younger adults Synonym: xanthelasma, xanthoma palpebrarum. (05 Mar 2000) |
| xanthematin | A yellow substance derived from haematin by treating with nitric acid. (05 Mar 2000) |
| xanthemia | Synonym: carotenaemia. Origin: xanth-+ G. Haima, blood (05 Mar 2000) |
| xanthene | <chemical> A yellowish, alcohol and ether soluble compound that serves as the chemical core for the dyes fluoroscein, eosin and rhodamine, by itself, xanthene is used as a fungicide and in organic synthesis. (11 May 1997) |
| xanthene dyes | Derivatives of the compound xanthene; include the pyronins, rhodamines, and fluoresceins. (05 Mar 2000) |
| xanthic | 1. Tending toward a yellow colour, or to one of those colours, green being excepted, in which yellow is a constituent, as scarlet, orange, etc. <botany> Xanthic colours, those colours (of flowers) having some tinge of yellow; opposed to cyanic colours. See Cyanic. 2. <chemistry> Possessing, imparting, or producing a yellow colour; as, xanthic acid. Of or pertaining to xanthic acid, or its compounds; xanthogenic. Of or pertaining to xanthin. <chemistry> Xanthic acid, a heavy, astringent, colourless oil, C2H5O.CS.SH, having a pungent odour. It is produced by leading carbon disulphide into a hot alcoholic solution of potassium hydroxide. So called from the yellow colour of many of its salts. Called also xanthogenic acid. Origin: Gr. Xanqos = yellow: cf. F. Xanthique. Source: Websters Dictionary (01 Mar 1998) |
| xanthide | <chemistry> A compound or derivative of xanthogen. See: Xantho-. Source: Websters Dictionary (01 Mar 1998) |