| A-LAK | adherent lymphokine-activated killer [cell] |
|---|---|
| APC | acetylsalicylic acid, phenacetin, and caffeine; activated protein C; adenoidal-pharyngeal-conjunctiv... |
| APTT, aPTT | activated partial thromboplastin time |
| ATC | activated thymus cell; around the clock |
| BaFBr:Eu | europium-activated barium fluorohalide |
| immunologically activated cell | An immunocyte that is in an elevated state of reactivity capable of carrying out an immune response, in contradistinction to an immunologically competent cell. (05 Mar 2000) |
|---|---|
| thiol activated haemolysins | Cytolytic bacterial exotoxins that act by binding to cholesterol in cell membranes and forming ring like complexes that act as pores. SH groups of these toxins must be in the reduced state for the toxin to function. Oxidation (to disulphide bridges) inactivates the toxin. Examples: tetanolysin, streptolysin O, _ toxin, cereolysin. (18 Nov 1997) |
| TNF-IL1-activated protein kinase | <enzyme> Phosphorylates beta casein in vitro; not the same as casein kinase 1 and casein kinase 2; not activated by mitogens, celllular stresses or any other cytokines than il1 and tnf Registry number: EC 2.7.1.- Synonym: tip kinase, beta casein kinase (26 Jun 1999) |
| Fas-activated serine-threonine kinase | <enzyme> Phosphorylates tia-1 during fas-mediated apoptosis; contains proline-rich sh3-binding domains; mw 60-63 kD; genbank x86779 Registry number: EC 2.7.10.- Synonym: fast kinase (26 Jun 1999) |
| killer cells, lymphokine-activated | Cytolytic lymphocytes with the unique capacity of killing natural killer (nk)-resistant fresh tumour cells. They are interleukin-2-activated nk cells that have no MHC (major histocompatibility complex) restriction or need for antigen stimulation. Lak cells are used for adoptive immunotherapy in cancer patients. (12 Dec 1998) |
| fluorescence-activated cell sorter | <technique> Flow cytometry is an emerging technique which holds great promise for the separation, classification and quantitation of blood cells and antibodies which affect blood cells. Complex computerised instruments are used to pass a monocellular stream of cells, platelets or other microscopic particulate elements through a beam of laser light. The cells are categorised first by size and then computer analysed to sort the mixture of cellular elements into cell type by size. Cells are labelled with fluorescent dye and then passed, in suspending medium, through a narrow dropping nozzle so that each cell is in a small droplet. A laser based detector system is used to excite fluorescence and droplets with positively fluorescent cells are given an electric charge. Charged and uncharged droplets are separated as they fall between charged plates and so collect in different tubes. The machine can be used either as an analytical tool, counting the number of labelled cells in a population or to separate the cells for subsequent growth of the selected population. Further sophistication can be built into the system by using a second laser system at right angles to the first to look at a second fluorescent label or to gauge cell size on the basis of light scatter. The great strength of the system is that it looks at large numbers of individual cells and makes possible the separation of populations with, for example: particular surface properties. Tabulation of counted data in conjunction with size analysis enables determination of relative percentages of each specific cellular subset for which monoclonal antibody conjugates are utilised, even when the size of the cell is identical to other subset species. Flow cytometry is a slightly imprecise but common term for the use of the Fluorescence-activated Cell Sorter (FACS). (01 Dec 1998) |
| fluorescence-activated cell sorting | <technique> A technique for separating and sorting cells marked with a fluorescent label based on how much they fluoresce at a particular wavelength. (12 Jan 1998) |
| light-activated resin | A resin which uses visible or ultraviolet light to excite a photoinitiator which interacts with an amine to form free radicals and initiate polymerization. Used mainly in restorative dentistry. Synonym: light-activated resin. (05 Mar 2000) |
| active carbon dioxide | Activated carbon dioxide, a complex of N-carboxybiotin (biotin + CO2) and an enzyme; the form in which carbon dioxide is added to other molecules in carboxylations; e.g., to methylcrotonyl-CoA to form beta-methylglutaconyl in the catabolism of leucine, and to acetyl-CoA to form malonyl-CoA. See: acetyl-CoA carboxylase. (05 Mar 2000) |
| anomeric carbon | The reducing carbon of a sugar; C-1 of an aldose, C-2 of a 2-ketose. (05 Mar 2000) |
| arteriovenous carbon dioxide difference | <physiology> The difference in carbon dioxide content (in ml per 100 ml blood) between arterial and venous blood. (05 Mar 2000) |
| carbon | <chemistry, element> Sixth element (Z=6) in the periodic table, has 6 protons, often described as the basis of life on earth because of its chemical properties, has potential for use with silicon as a low-activation structural material for fusion reactors, in the form silicon carbide. Carbon tiles are often used in plasma-facing components because its low Z makes carbon a relatively nice impurity. It is also useful as a neutron moderator. See: low-activation materials, plasma-facing components. Abbreviation: C (13 Nov 1997) |
| carbon-11 | A cyclotron-produced, positron-emitting radioisotope of carbon with a half-life of 20.3 minutes; used in positron-emitting tomography. (05 Mar 2000) |
| carbon-12 | The standard of atomic mass, 98.90% of natural carbon. (05 Mar 2000) |
| carbon-13 | A stable natural isotope, 1.1% of natural carbon. (05 Mar 2000) |