| dP/dV | pressure per unit change in volume |
|---|---|
| dZ | impedance change |
| LCU | life change unit |
| MC | mass casualties; mast cell; Master of Surgery [Lat. Magister Chirurgiae]; maximum concentration; Med... |
| MCD | magnetic circular dichroism; mast-cell degranulation; mean cell diameter; mean of consecutive differ... |
| zone electrophoresis | <chemistry, procedure> A type of electrophoresis used by physical chemists. In it, the components of a mixture are separated into distinct zones by moving the solution through a porous medium such as filter paper. (06 May 1997) |
|---|---|
| zone of inhibition | <microbiology> The area of no bacterial browth around an antimicrobial agent in the disk-diffusion test. (09 Oct 1997) |
| zone of optimal proportion | <chemistry> A zone in a solution of mixed antigen in which the two biomolecules are totally combined. (11 May 1997) |
| zone of polarizing activity | <cell biology> The small group of mesenchyme cells in avian limb buds that is located at the posterior margin of the developing bud and that produces a substance, possibly retinoic acid, that provides positional information to the developing limb bud. (18 Nov 1997) |
| foetal zone | An extensive area of the adrenal gland present in primates during foetal life and for a short period after birth; located between the definitive cortex and the medulla, it contains large steroid-secreting cells arranged in a reticular pattern; involution of this zone in humans is largely completed by three months after birth. Synonym: androgenic zone, foetal reticularis, foetal zone, provisional cortex. (05 Mar 2000) |
| language zone | A large area of the cerebral cortex on the left side (in right-handed persons) considered by some to embrace all the centres of memories and associations connected with language. (05 Mar 2000) |
| latent zone | That portion of the cerebral cortex, the stimulation of which produces no movement and a lesion of which produces no symptoms; mainly the more anterior areas of the frontal lobes. (05 Mar 2000) |
| frontal zone contraction theory | Model proposed to account for the movement of giant amoebae in which cytoplasmic contraction at the front of the leading pseudopod (fountain zone) pulls viscoelastic cytoplasm forward in the centre of the cell and forms a tube of more rigid cytoplasm immediately below the plasma membrane behind the active region. The peripheral contracted cytoplasm relaxes into a weaker gel at the rear and is pulled forward in its turn. Contrasts with the ectoplasmic tube contraction model. (18 Nov 1997) |
| Lissauer's marginal zone | A longitudinal bundle of thin, unmyelinated and poorly myelinated fibres capping the apex of the posterior horn of the spinal gray matter, composed of posterior root fibres and short association fibres that interconnect neighboring segments of the posterior horn. Synonym: fasciculus dorsolateralis, tractus dorsolateralis, dorsolateral tract, fasciculus marginalis, Lissauer's bundle, Lissauer's column, Lissauer's fasciculus, Lissauer's marginal zone, Lissauer's tract, marginal fasciculus, Spitzka's marginal tract, Spitzka's marginal zone, Waldeyer's tract, Waldeyer's zonal layer. (05 Mar 2000) |
| activated clotting time | The most common test used for coagulation time in cardiovascular surgery. (05 Mar 2000) |
| activated partial thromboplastin time | The time needed for plasma to form a fibrin clot following the addition of calcium and a phospholipid reagent; used to evaluate the intrinsic clotting system. (05 Mar 2000) |
| A-H conduction time | Forward conduction of the cardiac impulse from atria to ventricles via the A-V node or any bypass tract, represented in the electrocardiogram by the P-R interval. P-H conduction time is from the onset of the P wave to the first high frequency component of the His bundle electrogram (normally 119 ± 38 msec); A-H conduction time is from the onset of the first high frequency component of the atrial electrogram to the first high frequency component of the His bundle electrogram (normally 92 ± 38 msec); P-A conduction time is from the onset of the P wave to the onset of the atrial electrogram (normally 27 ± 18 msec). (05 Mar 2000) |
| association time | Time elasping between a stimulus and the verbalised response to it. (05 Mar 2000) |
| biologic time | The concept that our appreciation of time varies with age and is governed by the neural organization of the individual; it obeys a logarithmic rather than an arithmetic law. (05 Mar 2000) |
| bleeding time | <haematology> A test which measures the time it takes for small blood vessels to close off and bleeding to stop. Abnormal results can be seen in those with congenital or acquired platelet function disorders or thrombocytopenia. (27 Sep 1997) |