time (redirected from time limits)

time (tim) a measure of duration. Symbol t.

---

activated partial thromboplastin time  (APTT) (aPTT) (PTT) the period required for clot formation in recalcified blood plasma after contact activation and the addition of platelet substitutes; used to address the intrinsic and common pathways of coagulation.

bleeding time  the duration of bleeding after controlled, standardized puncture of the earlobe or forearm; a relatively inconsistent measure of capillary and platelet function.

circulation time  the time required for blood to flow between two given points.

clotting time , coagulation time the time required for blood to clot in a glass tube.

inertia time  the time required to overcome the inertia of a muscle after reception of a stimulus from a nerve.

one-stage prothrombin time  prothrombin t.

prothrombin time  (PT) the rate at which prothrombin is converted to thrombin in citrated blood with added calcium; used to assess the extrinsic coagulation system of the blood.

reaction time  the time elapsing between the application of a stimulus and the resulting reaction.

stimulus-response time  reaction t.

thrombin time  (TT) the time required for plasma fibrinogen to form thrombin, measured as the time for clot formation after exogenous thrombin is added to citrated plasma.

---

time (tm)

n.

1. A duration or relation of events expressed in terms of past, present, and future, and measured in units such as minutes, hours, days, months, or years.

2. A certain period during which something is done.

---

time,

n a measure of duration.

time, clot retraction,

n the time required for a given quantity of blood to separate in the tube in which it has been placed. For 3 ml of blood at room temperature, 1 hour is normal. It is very slow in thrombocytopenia.

time, coagulation,

n the time required for blood clotting to begin in a capillary tube, normally 2 to 8 minutes. A coagulation time three times normal is a definite danger sign.

time, gel,

n (gelation time), the interval of time required for a colloidal solution to become a solid or semisolid jelly or gel. Usually refers to the working time of a hydrocolloid or alginate impression material.

time, gelation,

n See time, gel.

time limits,

n.pl the periods within which a notice of claim must be filed.

time, median lethal,

n (LD₅₀ time, MLT), the time required for 50% of a large group of animals or organisms to die after administration of a specified dose of radiation.

time, prothrombin

n (one-stage test), a gross but useful screening test of the completeness of the second and third stages of blood coagulation. Normal prothrombin time by the Quick method is 12 to 15 seconds. The time is affected by deficiencies of factor V or VII as well as of prothrombin. See also test, prothrombin consumption.

time, serum prothrombin,

n See test, prothrombin consumption.

time, setting,

n the length of time for a mixed preparation of materials to reach a state of hardness, measured from the start of the mixing. The end point for dental materials is usually determined by a penetration test.

---

time

a measure of duration. See under adjectives for specific times, e.g. bleeding time.

---

time chart

a graph on which the values of a variable are plotted on one axis and time on the other.

time cluster

a cluster of cases at particular points along a time axis.

developing time

for an x-ray film is about 3 to 5 minutes, but automatic processors complete the task in 90 seconds.

time gain compensation (TGC)

in ultrasonography, electronic amplification of returning sound waves, which are weaker because they come through deeper structures, is necessary so there is an even image density through the field. This is usually represented graphically by a TGC curve on most machines.

time graph

see time chart (above).

time horizon

the period until which the economic analysis under consideration applies.

time series

a distribution of data according to occurrence.

time-space series

a distribution of data according to the time and the place of occurrence.

time value

said of money; money now is more valuable than money later.