thromboplastin

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Related to thromboplastin time: Thrombin time

thromboplastin

 [throm″bo-plas´tin]
tissue thromboplastin factor III, a coagulation factor derived from several different sources in the body, such as brain and lung; it is important in the formation of extrinsic prothrombin converting principle in the extrinsic pathway of coagulation. Called also tissue factor. See also activated partial thromboplastin time.

throm·bo·plas·tin

(throm'bō-plas'tin),
A substance present in tissues, platelets, and leukocytes necessary for the coagulation of blood; in the presence of calcium ions thromboplastin is necessary for the conversion of prothrombin to thrombin, an important step in coagulation of blood. It is now generally believed that thromboplastin activity may be developed through blood (intrinsic) or tissue (extrinsic) systems. Tissue thromboplastin (factor III) interacts with factor VII and calcium to activate factor X; active factor X combines with factor V in the presence of calcium and phospholipid to produce thromboplastin activity (also commonly called thromboplastin).

thromboplastin

/throm·bo·plas·tin/ (-plas´tin) coagulation factor III.
tissue thromboplastin  coagulation factor III.

thromboplastin

(thrŏm′bō-plăs′tĭn)
n.
A protease that converts prothrombin to thrombin in the early stages of blood clotting. Also called thrombokinase.

thromboplastin

a plasma protein that initiates the clotting process by converting prothrombin to thrombin in the presence of calcium ions.

throm·bo·plas·tin

(throm'bō-plas'tin)
A substance present in tissues, platelets, and leukocytes necessary for the coagulation of blood; in the presence of calcium ions, thromboplastin is necessary for the conversion of prothrombin to thrombin, an important step in blood coagulation.
Synonym(s): platelet tissue factor, thrombokinase.

thromboplastin

Blood clotting factor III, an obsolete term referring to what is now known to be several blood clotting factors operating together.

thromboplastin

see BLOOD CLOTTING.

Thromboplastin

A protein in blood that converts prothrombin to thrombin.
Mentioned in: Prothrombin Time

thromboplastin

; thrombokinase catalyst (in tissues, platelets, leukocytes) which, in presence of calcium ions, aids conversion of prothrombin to thrombin

throm·bo·plas·tin

(throm'bō-plas'tin)
A substance present in tissues, platelets, and leukocytes necessary for the coagulation of blood.
Synonym(s): platelet tissue factor, thrombokinase.

thromboplastin (throm´bōplas´tin),

n a substance necessary to the coagulant activity of tissue extracts; also has been referred to as the direct activator of prothrombin and as a substance from plasma, platelets, and tissues that initiates thromboplastic activity in blood coagulation. See also thromboplastin, extrinsic.
thromboplastin, activated,
n See thromboplastin, extrinsic.
thromboplastin, cofactor of,
n See factor V.
thromboplastin, extrinsic,
n a direct prothrombin activator formed by the interaction of brain extracts, factors V and VII, and factor IV calcium (Ca++).
thromboplastin, incomplete,
n tissue thromboplastin.
thromboplastin, intrinsic (plasma thromboplastin, intrinsic prothrombin activator),
n a prothrombin activator formed from interaction of blood coagulation factors V, VIII, IX, and X and factor IV calcium (Ca++) with a foreign surface.
thromboplastin, partial time (PTT),
n a blood test used to determine von Willebrand disease, hemophilia, and to monitor anticoagulant medications. Normal coagulation time is 68 to 82 seconds. An updated form of the test, activated partial thromboplastin time (APTT), is replacing PTT.
thromboplastin, tissue,
n a factor in tissue extract responsible for coagulation of blood.

thromboplastin

a substance in blood and tissues which, in the presence of ionized calcium, aids in the conversion of prothrombin to thrombin. Extrinsic and intrinsic thromboplastin are formed as the result of the interaction of different clotting factors; the factors that combine to form extrinsic thromboplastin are not all derived from intravascular sources, whereas those that form intrinsic thromboplastin are.

activated partial thromboplastin time
see activated partial thromboplastin time.
extrinsic thromboplastin
the prothrombin activator formed as a result of interaction of coagulation factors III, VII, and X which, with factor IV, aids in the formation of thrombin.
thromboplastin generation time (TGT)
evaluates the first stage in blood coagulation by measuring the efficiency of prothrombinase formation.
intrinsic thromboplastin
the prothrombin activator formed as a result of interaction of coagulation factors V, VII, IX, X, XI and XII and platelet factor 3 (PF-3), which, with factor IV, aids in the conversion of prothrombin to thrombin.
plasma thromboplastin antecedent (PTA)
clotting factor XI; deficiency occurs in cattle and dogs, causing mild to severe bleeding tendencies called hemophilia C.
plasma thromboplastin component (PTC)
clotting factor IX; deficiency causes christmas disease. Called also Christmas factor, antihemophilic factor B, autoprothrombin II.
thromboplastin time
see activated partial thromboplastin time.
tissue thromboplastin
factor III, a material derived from several sources in the body (e.g. brain, lung), and is important in the formation of extrinsic prothrombin converting principle in the extrinsic pathway of blood coagulation. Called also tissue factor.
References in periodicals archive ?
Activated partial thromboplastin time and anti-Xa measurements in heparin monitoring: Biochemical basis for discordance.
Table 1: Clotting time of blood treated with mushroom extracts in activated Partial Thromboplastin Time (aPTT) assay.
Results (mean [+ or -] SD) of activated partial thromboplastin time (APPT) and prothrombin time (PT) assays (in seconds) and measurement of plasma fibrinogen levels from 5 avian species.
Platelet poor plasma was taken for estimation of prothrombin time and activated partial thromboplastin time with the help of coagulometer.
Determination of normal versus abnormal activated partial thromboplastin time and prothrombin time after cardiopulmonary bypass.
In univariate analysis, gender, hospital days, diabetic mellitus, peptic ulcer disease, hemoglobin, platelet, prothrombin time, activated partial thromboplastin time, glucose, creatinine, aspartate aminotransferase, alanine aminotransferase and albumin were significant predictors of death (all p [less than or equal to] 0.
To assess the coagulation profile, I recommend the use of the whole-blood clotting test ("red-top tube test"), described in my editorial, and the measurement of prothrombin time, partial thromboplastin time, platelets, and fibrinogen.
Subgroup analyses revealed a significant reduction in activated partial thromboplastin time for subgroups receiving high-dose ginkgo (240 mg per day or more) and for studies including only patients, not healthy volunteers; however, both findings were not considered clinically relevant.
Q Our pharmacy has started running partial thromboplastin time (PTT) tests on patients on a drug called argatroban.
If his prothrombin time and partial thromboplastin time are abnormal, fresh frozen plasma may help correct a clotting factor deficiency.
95%) met one of the three diagnostic criteria (an abnormality in either prothrombin time, partial thromboplastin time, or platelet count), and 32 patients (6.