| matrix mitochondrialis | The substance occupying the space enclosed by the inner membrane of a mitochondrion; it contains enzymes, filaments of DNA, ribosomes, granules, and inclusions of protein crystals, glycogen, and lipid. Synonym: mitochondrial matrix. (05 Mar 2000) |
|---|---|
| matrix processing peptidase | <enzyme> From matrix fraction of rat liver mitochondria; cleaves mitochondrial protein precursors; inhibited by metal chelators and reactived by mn2+; classified as EC 3.4.24.64 Registry number: EC 3.4.24.- Synonym: mitochondrial processing peptidase, mitochondrial processing protease, alpha-mpp, beta-mpp, p-52 protein, rat, p-55 protein, rat, mas1 protein, yeast, mas2 protein, yeast (26 Jun 1999) |
| matrix proteins | Proteins of the outer layer of the cell wall of gram-negative bacteria. (18 Nov 1997) |
| matrix retainer | A mechanical device designed to hold a matrix around a tooth during restorative procedures, usually by engaging the ends of the matrix band and drawing the band tight. (05 Mar 2000) |
| matrix unguis | The area of the corium on which the nail rests; it is extremely sensitive and presents numerous longitudinal ridges on its surface. According to some anatomists, the nail bed is the portion covered by the body of the nail, the nail matrix being only the part on which the root of the nail rests. Synonym: matrix unguis, keratogenous membrane, nail matrix, onychostroma. (05 Mar 2000) |
| matrix-associated helicase | <enzyme> Component of the pre-mRNA splicing complex; has atpase activity and DNA helicase activity on a partially double-stranded DNA substrate in the 3'-5' direction Registry number: EC 2.7.7.- Synonym: helicase mah (26 Jun 1999) |
| matron | 1. A wife or a widow, especially, one who has borne children; a woman of staid or motherly manners. "Your wives, your daughters, Your matrons, and your maids." (Shak) "Grave from her cradle, insomuch that she was a matron before she was a mother." (Fuller) 2. A housekeeper; especially, a woman who manages the domestic economy of a public instution; a head nurse in a hospital; as, the matron of a school or hospital. Jury of matrons, a jury of experienced women called to determine the question of pregnancy when set up in bar of execution, and for other cognate purposes. Origin: F. Matrone, L. Matrona, fr. Mater mother. See Mother. Source: Websters Dictionary (01 Mar 1998) |
| matronal | Of or pertaining to a matron; suitable to an elderly lady or to a married woman; grave; motherly. Origin: L. Matronalis. Source: Websters Dictionary (01 Mar 1998) |
| mattages | <zoology> A shrike or butcher bird; written also matagasse. Source: Websters Dictionary (01 Mar 1998) |
| matte | 1. <chemistry> A partly reduced copper sulphide, obtained by alternately roasting and melting copper ore in separating the metal from associated iron ores, and called coarse metal, fine metal, etc, according to the grade of fineness. On the exterior it is dark brown or black, but on a fresh surface is yellow or bronzy in colour. 2. A dead or dull finish, as in gilding where the gold leaf is not burnished, or in painting where the surface is purposely deprived of gloss. Origin: F. Matte; cf. F. Mat, masc, matte, fem, faint, dull, dim; said of metals. See Mate checkmate. Source: Websters Dictionary (01 Mar 1998) |
| matted | Having a dull surface; unburnished; as, matted gold leaf or gilding. Matted glass, glass ornamented with figures on a dull ground. See: Matte. Source: Websters Dictionary (01 Mar 1998) |
| matter | <chemistry> The material of the universe. (09 Jan 1998) |
| matter, gray | The cortex of the brain which contains nerve cell bodies. The gray matter is as opposed to the white matter, the part of the brain that contains myelinated nerve fibres. The gray matter is so named because it in fact appears gray. In the mysterious affair at styles (1920), agatha christie first quoted the fictional belgian detective hercule poirot in regard to his gray matter: 'this affair must be unravelled from within.' he tapped his forehead. 'these little grey cells. It is up to them as you say over here.' (12 Dec 1998) |
| matter, white | The part of the brain that contains myelinated nerve fibres. The white matter is white because it is the colour of myelin, the insulation covering the nerve fibres. The white matter is as opposed to the gray matter (the cortex of the brain which contains nerve cell bodies). (12 Dec 1998) |
| mattowacca | <zoology> An American clupeoid fish (Clupea mediocris), similar to the shad in habits and appearance, but smaller and less esteemed for food. Synonym: hickory shad, tailor shad, fall herring, and shad herring. Origin: Indian name. Source: Websters Dictionary (01 Mar 1998) |