| beta [Greek letter beta] | an anomer of a carbohydrate; buffer capacity; carbon separated from a carboxyl by one other carbon i... |
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| BGAg | blood group antigen |
| BGC | basal ganglion calcification; blood group class |
| BGD | blood group degradation |
| BGS | balance, gait, and station; blood group substance; British Geriatrics Society |
| I region associated antigens | Class II major histocompatibility (MHC) antigens. (18 Nov 1997) |
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| O antigens | Tetra and penta saccharide repeat units of the cell walls of gram-negative bacteria. They are a component of lipopolysaccharide. (18 Nov 1997) |
| oncofetal antigens | Tumour-associated antigen's present in foetal tissue but not in normal adult tissue, including alpha-fetoprotein and carcinoembryonic antigen. (05 Mar 2000) |
| T antigens | Tumour antigens associated wtih replication and transformation by certain DNA tumour viruses, including adenoviruses and papovaviruses. See: beta-haemolytic streptococci, tumour antigens. (05 Mar 2000) |
| epstein-barr virus nuclear antigens | Nuclear antigens encoded by epstein-barr virus genes. at least six nuclear antigens have been identified but their mechanism of action and role in B-cell transformation is still unknown. (12 Dec 1998) |
| tumour antigens | Antigens that may be frequently associated with tumours or may be specifically found on tumour cells of the same origin (tumour specific), tumour antigens may also be associated with replication and transformation by certain DNA tumour viruses, including adenoviruses and papovaviruses. Synonym: neoantigens. See: T antigens. (05 Mar 2000) |
| tumour-specific transplantation antigens | Surface antigen's of DNA tumour virus-transformed cells, which elicit an immune rejection of the virus-free cells when transplanted into an animal that has been immunised against the specific cell-transforming virus. (05 Mar 2000) |
| Jk antigens | See Blood Groups appendix. (05 Mar 2000) |
| K antigens | <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) |
| Le antigens | <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) |
| Lu antigens | 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) |
| Lyt antigens | A group of alloantigens that are present on either T or B murine lymphocytes, e.g., Lyt 2,3 is equivalent to human CD8. (05 Mar 2000) |
| ABO blood group | <haematology> The major human blood type system which describes the oligosaccharide glycoprotein antigens found on the surface of human blood cells. According to the type of antigen present, a person may be assigned a blood type of A, B, AB or O. A second type of antigen, the Rh factor, renders a positive or negative blood type. The ABO blood group system is important because it determines who can donate blood to or accept blood from whom. Type A or AB blood will cause an immune reaction in people with type B blood and type B and AB blood will cause a reaction in people with type A blood. Conversely, type O blood has no A or B antigens, so people with type O blood are universal donors. And since AB blood already produces both antigens, people who are type AB can accept any of the other blood types without suffering an immune reaction. (04 Jul 1999) |
| actinobacteria group | A group of gram-positive, heterogeneous bacteria. This group encompasses a range of morphologically, physiologically, and chemically different organisms and includes bacteria that form cocci, short rods, irregular rods, and mycelia that fragment. (12 Dec 1998) |
| alkyl group | <chemistry> A funtional group on an organic molecule which is derived from an alkane which has lost a hydrogen atom. (13 Nov 1997) |