thromboplastin

(redirected from thromboplastin time)
Also found in: Dictionary, Thesaurus, Encyclopedia.
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 ?
Relationship between diluted prothrombin time (dPT) ratios and prolongation of activated partial thromboplastin time (aPTT) in the presence of lepirudin.
2] Nonstandard abbreviations: DTI, direct thrombin inhibitor; DFXaI, direct factor Xa inhibitor; PT, prothrombin time; APTT, activated partial thromboplastin time.
Parameters were retrieved electronically and by manual chart review, including the exact timing of changes in the bivalirudin infusion and the corresponding partial thromboplastin time (PTT) values that were obtained for clinical monitoring at that time.
Prior to undergoing a renal biopsy, a prothrombin time (PT) and activated partial thromboplastin time (aPTT) were ordered and the patient was noted to have an elevated PT of 22.
How to interpret and pursue an abnormal prothrombin time, activated partial thromboplastin time, and bleeding time in adults.
1,2) The activated partial thromboplastin time (aPTT) is the most common monitoring method; however, it is only a surrogate measure of the plasma heparin concentration.
She had mild hyponatremia, a mild increase in activated partial thromboplastin time and prothrombin time, and a moderately raised fasting level of low-density lipoprotein; other biochemical tests were within normal limits.
The other data collected included demographic factors, diagnosis, Acute Physiology and Chronic Health Evaluation II score, Sequential Organ Failure Assessment score on the day of TEG testing (9), C-reactive protein concentration (10), fibrinogen concentration, International Normalised Ratio, activated partial thromboplastin time, active infection requiring antibiotics, thrombotic complications (deep vein thrombosis, pulmonary embolism, thrombotic stroke) and hospital mortality.
Screening coagulation assays revealed a prolonged prothrombin time (PT), prolonged activated partial thromboplastin time (aPTT), and low fibrinogen-activity level.
Measurements included complete blood count (CBC); platelets; PT; activated partial thromboplastin time (APTT); fibrinogen (clottable, immunological); coagulation factors II, V, VII, VIII, IX, X, XI, XII; anti-thrombin (AT); alpha-2 antiplasmin (AP); Protein C (PC); mixing studies; lupus anticoagulant screening; plasminogen; thrombin-anti-thrombin; fibrin degradation products (FDP); d-dimer; and thrombin time.
Lab data revealed activated partial thromboplastin time (PTT) prolonged at 103 which did not correct on mixing studies.
Blood pressure, leukocyte count, hemoglobin, platelet count, prothrombin time, activated partial thromboplastin time, C-reactive protein, serum electrolytes, alanine amino- transferase (ALT), serum protein, serum creatinine, urea nitrogen, proteinuria, and microscopic qualitative and quantitative (Addis count) urine analysis were evaluated.