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T Sylwestrowicz

Publications and source records attributed to T Sylwestrowicz.

32 records · Page 2Linked to original sources
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[Studies on the thrombocytopoietic factor. I. Elaboration of investigative methods].

The authors present a method of determination of the activity of the thrombocytopoietic factor (AT) by means of biological test on rats using 75-Se-selenomethionine for in vivo labelling of platelets. For suppression of endogenous thrombocytopoiesis the rats received antiplatelet rabbit serum which was used for investigations in the period of reactive hyperthrombocytosis. The thrombocytopoietic activity was expressed in radioactivity impulses per 1 mg of platelet protein of rats which permitted to eliminate the error-fraught determination of platelet count. A statistically significant rise in the thrombocytopoietic activity was demonstrated in rabbits with experimental thrombocytopenia as compared with the AT in healthy rabbits. The error of the method was 9.6-9.8 percent (P less than 0.05).

Animals↗
PubMedDate not supplied

[Studies on the thrombocytopoietic factor. II. Determination of thrombocytopoietic activity in patients with hematological syndromes (preliminary study)].

Using the biological test on rats the thrombocytopoietic activity (AT) was determined in sera of 13 patients with idiopathic thrombocytopenia (ITP), 5 patients with pancytopenia and bone marrow hypoplasia, 18 with thrombocytopenia developing during proliferative diseases of the haemopoietic system, and 4 patients with erythremia vera. A high mean thrombocytopoietic activity was demonstrated in ITP and this high activity was accounted for by significantly raised AT in acute thrombocytopenia. Increased AT was observed also in myeloproliferative syndromes associated with thrombocytopenia, while in pancytopenia with bone marrow hypoplasia and in erythremia vera AT seemed not increased independently of the stage of the disease. Greater number of cases will be necessary for drawing reliable conclusions.

Acute Disease↗
PubMedDate not supplied

[Studies of the thrombocytopoietic factor. III. Modification of the method of determination of serum thrombocytopoietic activity].

A medification of the previously described method of thrombocytopoietic activity (ATS) determination is reported using mouse instead of rats as laboratory animals. This makes possible to reduce significantly the volume of blood necessary for ATS determination. The error of the method was 8.6--11.6% when the results were calculated in impulses per 1 mg of platelet protein (imp/mg BP) and 5.5--9.2% when presented as a percentage of total activity adsorbed to the platelets.

Animals↗
PubMedDate not supplied

[Effect of platelet concentrate transfusions on the thrombopoietic activity in rats].

Rats were given selected doses of rabbit antiplatelet serum (APS) inducing after 6 hours thrombocytopenia at the level of 14% of the initial platelet count followed by a gradual rise in this count (after 12, 24 and 48 hours). Eight hours after APS administration the rats were given transfusion of a concentrate containing 1-2 X 10(9) fresh allogenic platelets (group A) or the same number of previously frozen platelets (group B). Rats receiving no concentrate after APS administration (group C) and rats receiving neither APS nor concentrate (group D) served as controls. Using a bioassay on mice the serum thrombocytopoietic activity (ATS) was determined in the rats and the platelet count was measured by the direct method. These determinations were done before and 24 and 48 hours after the experiment. It was shown that after 24 hours the values of the platelets (p less than 0.1) and ATS (p less than 0.001) were lower in group B than in the remaining groups. This suggests an inhibitory effect of the frozen concentrate on the ATS. After 24 hours the platelet count was highest in group A, and after 48 hours in group C, which suggests that transfusion of fresh concentrate has an immediate effect but in a later phase it inhibits spontaneous mechanisms effacing the thrombocytopenic effect.

Animals↗
PubMedDate not supplied

[Effect of splenectomy on blood serum thrombopoietic activity (ATS) in patients with hematopoietic diseases].

Thrombocytopoietic activity (ATS) was determined in tests on mice on the day before and on the 1st, 7th, and 14th days after splenectomy in 18 patients (13 with idiopathic thrombocytopenia, 5 with haemolytic anaemia). It was found that in patients with ITP and high-grade splenic destruction of platelets ATS increased on the first days after splenectomy. On the other hand, in ITP patients with low-grade splenic platelet destruction splenectomy decreased the value of ATS immediately after the operation. Splenectomy performed in cases with normal platelet count caused no greater changes in ATS in the first week. These observations suggest that in patients with increased splenic destruction of platelets ATS may be inhibited and this inhibition may be removed after splenectomy. Absent correlation between ATS and platelet count may indicate that the value of ATS is not of decisive importance in thrombocytopenia regression following splenectomy.

Adolescent↗