| K blood group | K blood group See Kell blood group, Blood Groups appendix. (05 Mar 2000) |
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| Kell blood group | <haematology, immunology> Blood type classification based on a group of erythrocyte antigens that is characterised by an antibody called anti-K. Multiple erythrocytic antigens that comprise at least three pairs of alternates and amorphs, determined by one complex gene or possibly several genes at closely linked loci. The system is important in transfusion reactions. Its expression involves the X chromosome. (21 Jun 2000) |
| family group | <zoology> The highest-ranking group of taxa whose names are regulated. The family group includes taxa at the ranks of superfamily, family, subfamily, tribe, and any other rank below superfamily and above the genus group that may be required, such as subtribe (09 Jan 1998) |
| ketole group | Carbons 1 and 2 of a 2-ketose (HOCH2CO-); trans-ketolation from d-xylose 5-phosphate to C-1 of aldoses is important in various metabolic pathways involving carbohydrates (e.g., photosynthesis, Dickens shunt); the two-carbon unit is transferred as a,beta-dihydroxyethyl thiamin pyrophosphate. (05 Mar 2000) |
| Kidd blood group | See Blood Groups appendix. (05 Mar 2000) |
| kidd blood-group system | A group of antigens consisting principally of jk(a) and jk(b), determined by allelic genes. Amorphs are encountered. Antibodies of these substances are usually weak and quite labile, stimulated by erythrocytes. (12 Dec 1998) |
| uukuniemi group viruses | A group of viruses in the genus phlebovirus of the family bunyaviridae, infecting vertebrates and vectored by ticks. Its members have not been associated with human disease though antibodies have been isolated from human sera. (12 Dec 1998) |
| laramie group | <geology> An extensive series of strata, principally developed in the Rocky Mountain region, as in the Laramie Mountains, and formerly supposed to be of the Tertiary age, but now generally regarded as Cretaceous, or of intermediate and transitional character. It contains beds of lignite, often valuable for coal, and is hence also called the lignitic group. See Chart of Geology. Source: Websters Dictionary (01 Mar 1998) |
| lateral group of axillary lymph nodes | Lymph nodes along the brachial vein that receive lymph drainage from most of the free superior limb and send efferent vessels to the central group of axillary lymph nodes. Synonym: nodi lymphatici brachiales, brachial lymph nodes. (05 Mar 2000) |
| Lewis blood group | <haematology> A pair of blood group activities associated with the A, B, H substances. Lewis Lea is a separate gene, whereas Leb arises from the combined activity of the enzymes specified by Le(a) and H genes. (18 Nov 1997) |
| lewis blood-group system | A group of dominantly and independently inherited antigens associated with the abo blood factors. They are glycolipids present in plasma and secretions that may adhere to the erythrocytes. The phenotype le(b) is the result of the interaction of the le gene le(a) with the genes for the abo blood groups. (12 Dec 1998) |
| linkage group | A set of two or more loci that have been shown by linkage analysis to be physically close in the genome but that have not yet been assigned to specific chromosomes. It is rapidly becoming an outmoded term. (05 Mar 2000) |
| llandeilo group | <geology> A series of strata in the lower Silurian formations of Great Britain; so named from Llandeilo in Southern Wales. See Chart of Geology. Source: Websters Dictionary (01 Mar 1998) |
| ludlow group | <geology> A subdivision of the British Upper Silurian lying below the Old Red Sandstone; so named from the Ludlow, in Western England. Source: Websters Dictionary (01 Mar 1998) |
| lutheran blood-group system | A complex blood group system having pairs of alternate antigens and amorphic genes, but also subject to a dominant independently segregating repressor. (12 Dec 1998) |