[Oxygen balance and regional blood flow in the gingival mucosa during exposure to head-pelvis (+Gz) acceleration]. / Kislorodnyi rezhim i regionarnyi krovotok tkanei slizistoi obolochki desnypri vozdeistvi peregruzki golova - taz (+Gz).

The information content of a new contact rheopolarographic procedure used to determine the oxygen balance and regional circulation of the gingival mucosa was measured, bearing in mind the applicability of the procedure as an objective index of human tolerance to +Gz acceleration. It was found that the parameters of the oxygen balance and regional circulation of the gingival mucosa were well correlated with blood pressure in the floor of the auricle. In contrast to the traditional methods for assessing tolerance to acceleration, the new procedure provides information about the health condition of the centrifuged subjects on a continuous basis. Variations in the oxygen balance and regional circulation of the gingival mucosa helped to identify compensatory reactions of the cardiovascular system in response to +Gz acceleration.

[Oxygen status and regional blood flow in the gingival mucosa as affected by lower body negative pressure]. / Kislorodnyi rezhim i regionarnyi krovotok slizistoi obolochki desny pri vozdeistvii otritsatel'nogo davleniia na nizhnuiu polovinu tela.

Five test subjects were exposed to lower body negative pressure (LBNP). During exposure their regional circulation and oxygen balance of the gingival mucosa were measured and electrocardiography and kinetocardiography were performed to calculate parameters of the left heart function. The study showed a distinct correlation between LBNP tolerance and the level of compensatory reactions of the gingival mucosa blood flow and the cardiovascular system as a whole. The subjects with a high LBNP tolerance showed well pronounced regional compensatory reactions of the gingival mucosa that were not accompanied by significant changes in the left heart function. The subjects with a moderate tolerance exhibited either weak or no regional compensatory reactions of the gingival mucosa and significant changes in the left heart function.

[Results of electrocardiographic examinations of the Saliut-5 crews in flight]. / Rezul'taty élektrokardiograficheskikh obsledovanii ékipazhei "Saliuta-5" v polete.

In Salyut-5 crewmembers, electrocardiograms were recorded in 12 standard and D--S leads. No marked changes in bioelectric properties of the myocardium were detected. However, during the second part of the mission B. V. Bolynov and V. M. Zholobov showed changes in the terminal portion of the ventricular complex in the left sternal leads. It is presumed that they were induced by repolarization anomalies due to neurohormonal effects on myocardial metabolism. Members of the second crew did not exhibit similar electrocardiographic changes.