[Effect of systematic gravitational forces on the external respiration function in conditions of prolonged immersion].

Test subjects were exposed to 13-day water immersion per se or combined with centrifugation. The immersion did not influence the state of ventilation and gas exchange at rest, diminished significantly the functional capabilities of external respiration. An exposure of the test subjects to acceleration during the second half of water immersion resulted in the normalization of the functional reserves of external respiration.

[Study of the antigenic structure of Salmonella by means of immunoelectrophoresis].

The method of immunoelectrophoretic analysis was applied to the study of the antigenic structure of 180 freshly-isolated and laboratory cultures of salmonellae belonging to 29 serological types. A complicated set of specific and common antigens of bacteria was revealed in direct and cross experiments with the use of homologous and heterogenous antisera; immunophoregrams were drawn for each of the serological type under study. General regularities in immunophoretic, diffuse and serological characteristics of the individual antigens of salmonellae were established.

[Arousal thresholds during stimulation of brain structures in nonanesthetized cats].

In cats, there was no apparent difference between the average low thresholds for evoking EEG arousal when stimulating the mesencephalic RF, thalamic CM or some cortical structures (sensorimotor area, inferior part of auditory Ep). Most of other cortical points had much higher thresholds (g. lateralis anterior, g.

[The disinhibitory influence of the activating system when artificially excited from different points in the brain].

EEG activation can be produced by electrical stimulation of some cortical points with the same threshold current strength as by the midbrain RF and thalamic CM stimulation. Near-threshold stimulation of all these points acting simultaneously with inhibitory conditioned signals does not disturb the effector inhibition but displays an EEG difference between negative signals: the fine differentiation sound evokes considerable EEG desynchronization, while the rough one does not change the background rhythms. The same stimulation combined with a positive signal which has been made ineffective by successive inhibition or extinction, reestablishes the intensive EEG activation in response to this signal and the effector conditioned reflex.

[Extinction of brain activation responses to direct electrical stimulation of its structures in normal awake cats].

In unrestrained cats, repeated electric stimulation of the mesencephalic reticular formation (MRF), center median (CM) of the thalamus, and different cortical areas: both the low--and the high--threshold points (in regard to the brain activation), with the threshold strength current evoked similar EEG reactions of activation which diminished and disappeared after 3--5 repetitions of the stimuli. The moderate strength current evoked, apart from the EEG activation, pseudoviolent movements (turning of the head, etc.) and changes in the breathing rate.