| H-V conduction time | Conduction of the cardiac impulse through the ventricular myocardium, represented by the QRS complex in the electrocardiogram. H-R conduction time is from the onset of the first high frequency component of the His bundle electrogram to the onset of the QRS complex of the surface electrocardiogram (normally 43 ± 12 msec); H-V conduction time is from the onset of the first high frequency component of the His bundle electrogram to the onset of the ventricular electrogram (normally approximates the H-R interval but may be a little shorter). Synonym: ventricular conduction. (05 Mar 2000) |
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| sinoatrial conduction time | <cardiology, physiology> The time required for an impulse to travel from the sinoatrial node to the atrium; estimated indirectly during asystole by halving the average interval from the premature beat to the following normal sinus beat of the atrium. (05 Mar 2000) |
| sinoatrial recovery time | <cardiology, physiology> Interval from the last paced P wave to the first succeeding spontaneous P wave (after 2 to 5 minutes of right atrial pacing at 120 to 140 beats per minute, and when expressed as percentage of control cycle length, it normally ranges from 115 to 159%). (05 Mar 2000) |
| space-time clustering | A statistically significant excess of cases of a disease, occurring within a limited space-time continuum. (12 Dec 1998) |
| Stypven time test | A test measuring the clotting time of plasma after addition of Russell's viper venom, useful in evaluating patients with deficiencies in factor X. Origin: Trade name styptic + venom (05 Mar 2000) |
| survival time | The period elapsing between the completion or institution of any procedure and death, the life-span of biologically or physically marked erythrocytes or other cells. (05 Mar 2000) |
| systolic time intervals | See: electromechanical systole, left ventricular ejection time, preejection period. (05 Mar 2000) |
| discrete time model | <epidemiology> A model in which the system jumps from one state to the next at fixed intervals or timesteps. These difference models are simple to understand but often difficult to analyse; Contrast continuous time models. The parameters in such a model refer to the amount of change over the finite timestep; they are sometimes referred to as finite rates. In a (rather precise) sense, a differential equation is what you eventually get from a difference equation when you let the timestep get smaller and smaller and smaller. (05 Dec 1998) |
| doubling time | <cell biology> The time taken for a cell to complete the cell cycle. (10 Oct 1997) |
| Duke bleeding time test | A bleeding time test in which an incision is made in the earlobe and the time until bleeding stops is measured. (05 Mar 2000) |
| incubation time | <microbiology> The time from the moment of inoculation (exposure) to the development of the clinical manifestations of a particular infectious disease. (13 Nov 1997) |
| inertia time | The interval elapsing between the reception of the stimulus from a nerve and the contraction of the muscle. (05 Mar 2000) |
| intra-atrial conduction time | The total duration of electrical activity of the atria in one cardiac cycle. (05 Mar 2000) |
| Ivy bleeding time test | A bleeding time test in which a sphygmomanometer is inflated to 40 mm Hg around the upper arm, a 5-mm deep incision is made on the flexor surface of the forearm, and the time is measured to cessation of bleeding. (05 Mar 2000) |
| thrombin time | Test of the conversion of fibrinogen to fibrin by thrombin in which clotting time of plasma mixed with a thrombin solution is measured. Time is prolonged by afibrinogenaemia, abnormal fibrinogen, or the presence of inhibitory substances, e.g., fibrin-fibrinogen degradation products, heparin. Reptilase, a thrombin-like enzyme unaffected by the presence of heparin, may be used in place of thrombin. (12 Dec 1998) |