PubMed Health⌕ Search

Biomedical subjects

N A Kuznetsov

Publications and source records attributed to N A Kuznetsov.

At least 91 records · Page 5Linked to original sources
PubMed1978

[Mechanisms of the hemodynamic disorder in embolisms of the major arteries of the extremities and the ways for their correction].

The main mechanisms of hemodynamic disorders are discussed and the means of correcting disturbances in homeostasis developing in embolism of the major arteries of the extremities are planned. It is shown that activation of the sympathico-adrenal system is the principal trigger mechanism of homeostasis disorders during acute occlusion of the vessels. This leads to the development of cardiac and pulmonary insufficiency. The restoration of circulation in the affected extremities is attended with the progression of cardiac, vascular, and pulmonary insufficiency. The different outcomes in the correction of 6- and 12-hour occlusion of the terminal aorta are mostly due to the different functional state of the cardiovascular system prior to correction.

Acid-Base Equilibrium↗
PubMed1978

[State of the "contraction-relaxation" mechanism and the bioelectric activity of the myocardium in acute arterial occlusion].

The results of 57 experiments on adult mongrel dogs are shown. Acute occlusion of the terminal aorta was reproduced by means of a balloon catheter. The pressure in the cavity of the left ventricle and in the office of the aorta and the ECG were recorded synchronously. The load experienced by the heart grew by the 6th hour of occlusion of the terminal aorta. This is attended by disorders in excitability and trophics of the myocardium and inhibition of the rate of myocardial contractions. At the same time the potency of the system of myocardial relaxation grows. By the 12th hour of occlusion of the terminal aorta, not only are the myocardial contractility and bioelectric activity impaired, but the capacity of the myocardial relaxation mechanism diminishes. The restoration of the circulation in the involved extremities is attended with further inhibition of the main functions of the heart. A new index of the functional condition of the myocardium, the restoration index, is proposed.

Action Potentials↗
PubMed1975

[Functional state of the cardiovascular system in experimental acute occlusion of the terminal segment of the aorta].

In 30 experiments on dogs a study was conducted of the pathophysiological mechanisms of the disorders in central haemodynamics and myocardial contractility during an acute occlusion of the terminal aorta and after reestablishment of the circulation in the diseases extremities. In response to the occlusion an elevation was noted in the total peripheral resistance, in the force and rate of the cardiac contractions, and a compensatory hyperfunction of the heart developed. By 6 hours of the occlusion the total peripheral resistance increased, the force and rate of the cardiac contractions decreased, the myocardial tension increased, the external work of the heart decreased, and myocardial hypodynamy developed. In 45 min following the restoration of the circulation a reduction of the total peripheral resistance was observed, the myocardial contractility was inhibited, the phase structure of the cardiac cycle was disturbed. A further observation for 45 min failed to reveal any changes in the indices of cardio- and haemodynamics, the phase structure of the cardiac contractions and myocardial contractility, as compared to the data obtained in the preceeding study.

Acute Disease↗
PubMedDate not supplied

[Rheologic effects of normovolemic hemodilution].

The effect of normovolemic hemodilution on blood viscosity has been studied in 79 patients with arterial obstruction in the lower extremities. It has been established that 21 to 25% hemodilution (which corresponds to hematocrit level of 0.34-0.36 l/l) was optimal for the correction of blood viscosity abnormalities. With this hemodilution level, the oxygen transport index reflecting blood oxygen transport function reached its maximum approaching the values of healthy persons. The most marked hemodilution effect was observed with slow shift rate.

Albumins↗
PubMedDate not supplied

[The mechanisms of hemodynamic shifts in normovolemic hemodilution].

Normovolemic hemodilution is shown to activate adaptation mechanisms of the heart, regional circulation and microvasculature. This is accompanied by a decline in the total peripheral resistance, an increase in venous return and intensification of the regional tissue blood flow. An increase in the cardiac output is due to mobilization of the functional cardiac reserve and is not accompanied by intensification of the heart work. Accelerated pulmonary circulation in normovolemic hemodilution may lead to functional shunting and blood oxygenation disturbances in patients with anatomic and functional respiratory changes.

Hemodilution↗
PubMedDate not supplied

The effect of diazane on the proliferation of human tumor cells.

The effect of the antitumorigenic agent diazane (1,2-bis-diazoacetylethane) in the cells of 30 human tumors cultured in vivo in diffusion chambers, implanted intraperitoneally into mice. Twenty-four hours after the introduction of diazane, a decrease in the proportion of DNA-synthesizing cells and the intensity of DNA synthesis to 30--50% of the control values is observed. By 48 hours, the values of these parameters had returned to the initial level.

Antineoplastic Agents↗