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S I Shevchenko

Publications and source records attributed to S I Shevchenko.

34 records · Page 2Linked to original sources
PubMed1989

[The blocking effect of aliphatic hydrocarbons on Ca2+ leakage channels formed by aggregates of Ca2+-ATPase of the sarcoplasmic reticulum].

The effects of aliphatic hydrocarbons within the liposomes on the Ca2+ transport function of isolated sarcoplasmic reticulum (SR) membranes of rabbit skeletal muscle, vesiculate preparation of Ca2+ dependent ATPase and proteoliposomes reconstituted from Ca2+-ATPase and egg phosphatidylcholine, were studied. It was shown that liposomes prepared from dipalmitoyl phosphatidylcholine containing aliphatic hydrocarbons increase 2 to 3 times Ca2+ accumulation by Ca2+-dependent ATPase from rabbit skeletal muscle SR. Ca2+ transport by SR vesicles increases in the presence of hydrocarbons by 15--20%. The activating effect of hydrocarbons on Ca2+ transport by proteoliposomes depends on the lipid/protein ratio. The proteoliposomes with a high lipid/protein ratio are practically insensitive to the effects of hydrocarbons. It was suggested that activation of Ca2+ transport by hydrocarbons is due to blocking of Ca2+ leakage channels formed during the aggregation of Ca2+-ATPase molecules. Treatment of membranes by formaldehyde results in the oligomerization of Ca2+-ATPase and decreases 2--4-fold the ATP-dependent accumulation of Ca2+. Subsequent addition of decane restores Ca2+ transport practically completely.

Animals↗
PubMed1989

[Quantitative immunomorphological criteria in the diagnosis of thyroid diseases].

Quantitative assessment of the degree of pronouncement of lymphoid infiltration in the micropreparations of the thyroid gland (TG) allows to define the index of lymphoid infiltration according to which autoimmune reactions and autoimmune diseases can be differentiated. Similar reaction of stroma in cancer, nodular and mixed euthyroid, goiter and TG adenoma permits to consider the patients with nodular goiter as a group of risk for the development of cancer.

Adenoma↗
PubMed1982

Microbial transformations of inorganic sulphur compounds in soil under conditions of heterocontinuous cultivation.

Development and activity of the association of the sulphur cycle bacteria, represented by Thiobacillus thioparus and Desulfovibrio sp., were followed in chernozem soil continuously supplemented with sodium thiosulphate. The technique of heterocontinuous cultivation made it possible (i) to determine changes in the individual components of microflora involved in successive metabolic steps, their time and space sequence, (ii) to follow changes in the transformations of substrate and formation of metabolic products, and (iii) to reach a steady state in the system. A possible use of this approach for the evaluation of the effect of ecological factors, for modelling microbiological processes of the sulphur cycle, for the investigation of trophic relationships among microorganisms in natural and artificial association and for the evaluation of the geochemical activity of sulphur bacteria is discussed.

Biotransformation↗