| CNL | cardiolipin natural lecithin; chronic neutrophilic leukemia |
|---|---|
| DND | died a natural death |
| e | base of natural logarithms, approximately 2.7182818285; egg transfer; ejection; electric charge; ele... |
| LGL-NK | large granular lymphocyte-natural killer |
| ln | natural logarithm |
| natural language processing | Computer processing of a language with rules that reflect and describe current usage rather than prescribed usage. (12 Dec 1998) |
|---|---|
| natural mutation | A mutation which occurs by itself without first being affected by a mutagen, for example during the process of DNA replication. Spontaneous mutations arise at a remarkably constant rate. The rate that spontaneous mutations arise has been used as an evolutionary clock to estimate how closely related two (or more) separate species are to each other. (09 Oct 1997) |
| natural passive immunity | Immunity conferred by the mother on the foetus or newborn. (14 Nov 1997) |
| natural pigment | A naturally occurring coloured compound; absorbs light in the visible range of the electromagnetic spectrum. Compare: structural colour. Synonym: biochrome. (05 Mar 2000) |
| natural products | Naturally occurring compounds that are end products of secondary metabolism; often, they are unique compounds for particular organisms or classes of organisms. (05 Mar 2000) |
| natural selection | The hypothesis that genotype environment interactions occurring at the phenotypic level lead to differential reproductive success of individuals and hence to modification of the gene pool of a population. (18 Nov 1997) |
| immunity, natural | The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from non-specific mechanisms such as genetic endowment, naturally occurring antiviral and bactericidal substances, phagocytosis, and constitutional factors such as body temperature, oxygen tension, and age. (12 Dec 1998) |
| killer cells, natural | Cells responsible for spontaneous cytotoxicity of a variety of tumour cells without prior immunization. These natural killer cells are found in non-immune humans and experimental animals and are thought by some to be the same as killer cells (killing by antibody-dependent cell cytotoxicity), but they can also kill in the absence of antibody. (12 Dec 1998) |
| absolute CD4 count | The number of helper T-lymphocytes in a cubic millimeter of blood. With HIV, the absolute CD4 count declines as the infection progresses. The absolute CD4 count is frequently used to monitor the extent of immune suppression in persons with HIV. Also called a T4 count. (12 Dec 1998) |
| absolute eosinophil count | <haematology, investigation> A measurement (cells per microlitre) of the number of eosinophils in a blood specimen. This measurement is useful in the evaluation of autoimmune disease, allergies, eczema, leukaemia, asthma and hay fever. Normal absolute eosinophil counts are less than 350 cells/mcl (microlitre). (27 Sep 1997) |
| Addis count | A quantitative enumeration of the red blood count, white blood count, and casts in a 12-hr urine specimen; used to follow the progress of known renal disease. (05 Mar 2000) |
| Arneth count | The percentage distribution of polymorphonuclear neutrophils, based on the number of lobes in the nuclei (from 1 to 5). See: Arneth index. (05 Mar 2000) |
| b and t cell count | A test that measures the respective quantities of B lymphocytes and T lymphocytes. This test is often performed in the analysis of an immune deficiency disorder. Normal values include: 68 to 75% of total lymphocytes are T lymphocytes and 10 to 20% are B lymphocytes. Increased T-cell counts can indicate infectious mononucleosis, acute lymphocytic leukaemia or multiple myeloma. Increased B lymphocytes can indicate chronic lymphocytic leukaemia, multiple myeloma, Waldenstrom's macroglobulinaemia or Di George syndrome. Decreased T-cells may indicate congenital T-cell deficiency, Wiskott-Aldrich syndrome or AIDS. Decreased B-cells may indicate acute lymphocytic leukaemia or a congenital immunoglobulin deficiency disorder. (27 Sep 1997) |
| blood cell count | A count of the number of leukocytes and erythrocytes per unit volume in a sample of venous blood. A complete blood count (cbc) also includes measurement of the haemoglobin, haematocrit, and erythrocyte indices. (12 Dec 1998) |
| blood count | <haematology, investigation> The determination of the proper number of red blood cells, white blood cells and platelets are present in the patients blood. Acronym: FBC (16 Dec 1997) |