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Related to thromboplastin time: Thrombin time


see blood clottingblood clotting,
process by which the blood coagulates to form solid masses, or clots. In minor injuries, small oval bodies called platelets, or thrombocytes, tend to collect and form plugs in blood vessel openings.
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(Factor III), an important coagulation factor in the blood-clotting system; it helps convert prothrombin into thrombin. Thromboplastin is localized in the membranes of formed elements of the blood and in the cells of various organs. A large amount of thromboplastin enters the blood upon injury to tissues. Brain and lung tissues have especially high thrombo-plastic activity, and lung thromboplastin also takes part in the metabolism of the vasoactive polypeptides angiotensin and bradykinin.

Chemically, thromboplastin is a protein-lipid complex. The basis of its activity is its lipid constituent, which contains serine, eth-anolamine, and choline phosphatides. Blood coagulation factors are adsorbed on the phospholipid micelle, creating favorable conditions for the enzymatic reactions involved in blood clotting.

The term “thromboplastin” is sometimes used to designate an active complex that includes, in addition to thromboplastin, a number of protein factors and Ca2+ ions. Such active thromboplastin, which directly converts prothrombin into thrombin, is also called thrombokinase or prothrombinase. Thromboplastin is used in clinical practice to determine the prothrombin level, an indicator of the condition of the blood-clotting system.



Any of a group of lipid and protein complexes in blood that accelerate the conversion of prothrombin to thrombin. Also known as factor III; plasma thromboplastin component (PTC).
References in periodicals archive ?
activated partial thromboplastin time for monitoring unfractionated heparin: A pilot study.
As both Prothrombin time and Activated Partial Thromboplastin Time were deranged during hospital stay and at multiple times in the previous records, factor levels were sent.
As previously mentioned, the incidence of bleeding is minimized with normal partial thromboplastin time, prothrombin time, platelet count, and bleeding time.
aPTT, a modified version of the activated Partial Thromboplastin Time test, is a test that measures the intrinsic pathway of coagulation.
Several screening tests are available for evaluating coagulation pathways: activated partial thromboplastin time (APTT), prothrombin time (PT), and thromboelastography (TEG).
In afibrin-ogenemia, prothrombin time, thrombin time and activated partial thromboplastin time are prolonged and there is no fibrinogen in the blood (2).
Hence present study is undertaken to see the effect of type 2 diabetes on platelet aggregation, prothrombin time and activated partial thromboplastin time.
Assessment of coagulation status of patients was done using coagulation tests: activated partial thromboplastin time (APTT) and international normalized ratio (INR).
There were significant differences in age, gender, hospital days, peptic ulcer disease, hemoglobin, platelet, prothrombin time, activated partial thromboplastin time, and all biochemistry tests.
5) or prolonged activated partial thromboplastin time (aPTT >50 seconds).
Hematological parameters, including hemoglobin, hematocrit, platelet count, peripheral smear, erythrocyte sedimentation rate, electrolytes, bleeding time, prothrombin, thrombin, and partial thromboplastin time, and coagulation factors are usually within normal limits.