[Comparative characteristics of the biological aggressiveness of welding dusts].

The article contains a study of the cytotoxic properties of welding dusts (WD) and their capacity to activate lipoid peroxidation (LP) depending on the particles of chemical composition. A correlation was established between the WD cytotoxic properties, activation of LP in the lungs and the concentration of cremnium dioxide.

[Plasma erythropoiesis inhibitors in humans during hyperbaric hyperoxia].

Before exposure of man to hyperbaric hyperoxia the blood plasma possessed marked erythropoietic activity. Erythropoietins disappeared completely and erythropoiesis inhibitors appeared in the plasma of persons untrained to hyperbaric hyperoxia after a 24-hour exposure to hyperoxic conditions (25% of oxygen in the inhaled air) in the high pressure chamber corresponding to the depth of 63 metres. A reduction of the peripheral red blood indices was observed by that time.

[Influence of hypoxia and hyperoxia on the 2,3-diphosphoglycerate concentration in rat red blood cells].

The influence of hypoxia (pO2 = 85 mmHg) lasting 5 h, a strong single bleeding of the animals, and the effect of hyperoxia (pO2 = 745 and 1520 mmHg) lasting 24 and 5 h, respectively, on the 2.3-DPG concentration of red cells from rat has been studied. A distinct increase in 2.

[Effect of hyperoxia on the rate of restoration of blood composition after blood loss].

Regeneration of the peripheral red blood was considerably retarded in the anemic rabbits (blood letting of 2% of body weight) after a 5-hour exposure to the hyperoxiconditions (98% of oxygen in the inhaled air, 2 ata).

[Erythropoietic activity of human blood following exposure to hyperbaric hyperoxygenation].

Before exposure of man to hyperoxia the blood plasma posessed erythropoietic activity, but 18 to 20 hours after exposure to compressed air condition in the high pressure chamber corresponding to the depth of 100 metres there proved to be a marked fall of the erythropoietic activity. No statistically significant shifts were revealed in the peripheral blood indices by that time.

[Erythropoietic function of the kidneys under conditions of abnormally high oxygen pressure].

Three to five hours after 5-hour exposure of rabbits to high oxygen pressure (2 ata) the erythropoietin proved to disappear from both the arterial and the venous blood plasma of the kidneys. At the same time the blood plasma from the renal vein began to suppress the mitotic activity of erythroblastic cells in the bone marrow culture. These data testify to the fact that under hyperbaric hyperoxia the kidneys secreted the inhibitor of erythropoiesis.