[Obtaining active extracts for use in production of soluble thromboplastin].

Methods of obtaining (from cadaveric human brain) the highly-active extracts to be used later as raw-materials for thromboplastin manufacturing, which is applied to determine the prothrombin (thromboplastin) time of human plasma or blood, are described in the paper. The study resulted in defining the optimal requirements to choosing the raw-materials, storing regime, centrifuging and extraction. The thus elaborated technology of soluble thromboplastin manufacturing ensures the production of a reagent with a high sensitivity to a changing level of factors VII and X and to a reducing activity of the prothrombin complex, which is achieved through the impact of indirect anticoagulants.

[Effect of activators for activated partial thromboplastin time test on its results in the tube and automated test versions].

Effects of activators used in combination with partial thromboplastin (PT), manufactured by the Kirov Institute of Hematology and Blood Transfusion, on the results of the activated partial thromboplastin time (APTT) test and its sensitivity to heparin were studied. Kaolin manufactured in Russia and by Aldrich firm and silica from Sigma were used. The method was reproduced in tubes and on Organon Teknika photooptic coagulometers: semiautomatic Coag-A-Mate XM and automated Coag-A-Mate RA-4.

[The quality indices of the Quick method using thromboplastin reagents performed manually and instrumentally].

The reproduction and results of Quick's method with tissue thromboplastin (Kirov Institute of Hematology and Blood Transfusion--KIHBT) and Excel and Excel S simplastins (Organon Teknika, Netherlands) in the tube and automated versions were compared. Semiautomated coagulometer COAG-A-MATE XM and automated COAG-A-MATE RA-4 of the same firm were used. Three Verifi plasmas (Organon Teknika) with different activities of factors II, VII, IX, and X were used.

[The evaluation of lyophilized plasma as a reference standard for the prothrombin complex].

Analysis of a number of parameters of a lyophilized donor plasma reference sample to be used for the assessment of the prothrombin complex factors has shown the stability of this sample over the course of 14 months (a follow-up period). The sample may be used as a reference one in estimation of plasma prothrombin complex factor activities, and of PPSB activity. The reference sample activity should be estimated from the fresh donor plasma native pool, whose procoagulant activity is conventionally estimated as 100% or 1 U/ml.

[Evaluation of single-stage methods of studying the activity of factor VIII].

Accurate diagnosis of coagulopathies related to changed factor VIII activity, studies of specific activities of antihemophilic cryoprecipitate globulin used for hemostatic correction in patients, and monitoring of therapy efficacy are impossible without a reproducible, sensitive, standard, and available method. The authors have compared two single-stage methods developed by Soviet scientists: that by V. P.