| antirachitic vitamins | Ergocalciferol (v. D2) and cholecalciferol (v. D3). (05 Mar 2000) |
|---|---|
| vitamins | For the various vitamins see Vitamins. The word vitamin was coined in 1911 by the warsaw-born biochemist casimir funk (1884-1967). at the lister institute in london, funk isolated a substance that prevented nerve inflammation (neuritis) in chickens raised on a diet deficient in that substance. He named the substance vitamine because he believed it was necessary to life and it was a chemical amine. The e at the end was later removed when it was recognised that vitamins need not be amines. The letters (a, b, c and so on) were assigned to the vitamins in the order of their discovery. The one exception was vitamin k which was assigned its k from koagulation by the danish researcher henrik dam. (12 Dec 1998) |
| fat-soluble vitamins | Those vitamin's, soluble in fat solvents (nonpolar solvents) and relatively insoluble in water, marked in chemical structure by the presence of large hydrocarbon moieties in the molecule; e.g., vitamin's A, D, E, K. (05 Mar 2000) |
| achromatic vision | A severe congenital deficiency in colour perception, often associated with nystagmus and reduced visual acuity. Synonym: achromatic vision, monochromasia, monochromasy, monochromatism. Origin: G. A-priv. + chroma, colour, + opsis, vision (05 Mar 2000) |
| binocular vision | Vision with a single image, by both eyes simultaneously. (05 Mar 2000) |
| blue vision | A condition in which all objects appear blue; may temporarily follow cataract extraction. Synonym: blue vision, cyanopia. Origin: cyano-+ G. Opsis, vision (05 Mar 2000) |
| red vision | An abnormality of vision in which all objects appear to be tinged with red. Synonym: red vision. Origin: erythro-+ G. Ops, eye (05 Mar 2000) |
| vision | 1. <ophthalmology> The act or faculty of seeing, sight. 2. <psychiatry> An apparition, a subjective sensation of vision not elicited by actual visual stimuli. 3. Visual acuity, symbol V. Origin: L. Visio (18 Nov 1997) |
| vision, binocular | The blending of separate images seen by each eye into one composite image. (12 Dec 1998) |
| vision disorders | Visual impairment limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, colour vision, or peripheral vision. Visual disability refers to inability of the individual to perform specific visual tasks, such as reading, writing, orientation, or traveling unaided. It is to be differentiated from eye diseases which are restricted to diseases of the eye, the organ and its anatomical parts. (12 Dec 1998) |
| vision disparity | The difference between two images on the retina when looking at a visual stimulus. This occurs since the two retinas do not have the same view of the stimulus because of the location of our eyes. Thus the left eye does not get exactly the same view as the right eye. (12 Dec 1998) |
| vision, entoptic | Visual sensation due to shadows or optical effects of structures within the eye or to excitation of the receptor system by stimuli other than light. (12 Dec 1998) |
| vision, monocular | Vision with one eye or the affecting of one eye. (12 Dec 1998) |
| vision screening | Application of tests and examinations to identify visual defects or vision disorders occurring in specific populations, as in school children, the elderly, etc. It is differentiated from vision tests, which are given to evaluate/measure individual visual performance not related to a specific population. (12 Dec 1998) |
| vision, subnormal | Vision considered to be inferior to normal vision as represented by accepted standards of acuity, field of vision, or motility. (12 Dec 1998) |