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Related to antithrombin: heparin, Antithrombin deficiency


any naturally occurring or therapeutically administered substance that neutralizes the action of thrombin and thus limits or restricts blood coagulation.
antithrombin I fibrin, referring to the capacity of fibrin to adsorb thrombin and thus neutralize it.
antithrombin III a naturally occurring inhibitor of blood coagulation; it is an α2-globulin member of the serpin group, synthesized in the liver and found in the plasma and various extravascular sites. It inactivates thrombin as well as certain coagulation factors and kallikrein. Inherited deficiency of the protein, an autosomal dominant disorder, is associated with recurrent deep vein thrombosis and pulmonary emboli. Complications from the disorder are prevented and, in conjunction with heparin, treated with a preparation of antithrombin III from pooled human plasma, administered intravenously.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Any substance that inhibits or prevents the effects of thrombin in such a manner that blood does not coagulate. A deficiency of antithrombin results in impaired inhibition of coagulation factors IIa, IXa, and Xa in plasma, causing recurrent thrombosis.
Farlex Partner Medical Dictionary © Farlex 2012


A plasma protein that diminishes the activity of THROMBIN, or the amount of thrombin produced during or following coagulation of the blood.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


Any substance that counters the effect of thrombin, an enzyme that converts fibrinogen into fibrin, leading to blood coagulation.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
At the same time, there was negative correlation between procalcitonin and protein C (p=0.044; r=-0.189); antithrombin III and CRP (p=0.018; r=-0.220), while antithrombin III and protein C (p=0.001; r=0.417) and protein C and protein S (p=0.010; r=0.240) had positive correlation.
(8.) Lotta LA, Martinelli I, Peyvandi F (2012) Prothrombin mutation conveying antithrombin resistance.
Antithrombin concentrate derived from pooled human plasma is indicated in the treatment and prevention of VTE in patients with hereditary AT deficiency whose AT activity is less than 70%.
Coagulation parameters (factor 2, 5, 8, 9, 10, 11, protein C and S, antithrombin III, active protein C resistance and homocysteine levels (2.38 mmol/L and 12 mmol/L, N 4-15)) were found to be normal.
If we aimed to decrease the within-subject individual variation to below 10%, the number of measurements is still 1 for PT and antithrombin. For the other tests more measurements would be required to achieve this precision, and for VWF:CB, for example, 82 measurements would be needed to obtain an analytical variation below 10% (Table 3), but in daily routine this precision is not needed.
Because of the limitation of our clinical laboratory, we could not examine other coagulation factors, such as protein C or S, antithrombin III.
Deficiencies of antithrombin, protein C and protein S--Practical experience in genetic analysis of a large patient cohort.
New antithrombin agents, such as vorapaxar, have shown efficacy in reducing the risk of new cardiovascular events in secondary prevention strategy but also showed an increased hemorrhagic risk [29]; this raises new questions about whether patients with high baseline TAT benefited more of such therapy and compensate the hemorrhagic risk and the possible regression or attenuation of the atherosclerosis process [9, 30, 31].
Antithrombin III (AT) is synthesized in liver and changes in its levels are associated with the extent of cirrhosis.
Janssen Pharmaceuticals, Inc., a Johnson & Johnson company, has acquired XO1 Ltd., a privately held virtual biopharma company founded to develop the antithrombin antibody ichorcumab.
Antinuclear antibody (ANA), protein C, S and antithrombin III tests were all negative.