PubMed Health⌕ Search

Biomedical subjects

D A Romanov

Publications and source records attributed to D A Romanov.

15 recordsLinked to original sources
PubMed1989

[Characteristics of the physiological functions in the operators of foundry transfer lines in the course of the work day and week].

The correlation analysis covered the state of the cardiovascular, hemodynamic, thermoregulatory, vegetative nervous systems, the characteristics of strength, endurance, attention, readiness to action among operators of transfer foundry lines during working days and weeks. It was shown that the main physiologic changes occurred at the initial stage, i. e., on the first day before the dinner break. To the end of the working week correlational links were established among temperature, arterial pressure, characteristics of strength, endurance, the time necessary for response and attention, thus higher intensity of the thermoregulatory system functioning being evidenced.

Adaptation, Physiological↗
PubMed1982

[Factor analysis of the mechanisms of the structure of sleep-wakefulness cycle].

As a result of factor analysis of the structure of the cat sleep--wakefulness cycle, six factors have been defined, regarded as factors of "paradoxical sleep", "structure of slow-wave sleep", "transitions or delta-sleep", "sleep of medium depth", "stage of sleep spindles" and "delta sleep". Along with the detected certain independence of the apparatuses controlling individual sleep stages it was shown that mechanisms of paradoxical sleep may determine the organization of the entire sleep--wakefulness cycle, representing a peculiar system-forming factor. A considerable part in cessation of the fast sleep, as well as in the sleep general mechanisms is played by the apparatuses responsible for the transitional processes between the stages.

Analysis of Variance↗
PubMed1981

[Electrophysiologic correlates of interaction between desynchronized and synchronized brain structures during sleep and wakefulness].

The relations of the basal preoptic area to mesencephalic RF, center median of the thalamus, hippocampus and posterior hypothalamus were studied in cats with the aid of positive wave (P-wave) evoked by preoptic stimulation during wakefulness and sleep. In light slow wave sleep, the amplitude and duration of P-wave increased for all the structures except hippocampus. Correlation between the P-wave amplitude in hippocampus and the duration of the paradoxical sleep was revealed. In paradoxical sleep, the P-wave of the mesencephalic RF and the center median was reduced as compared to wakefulness. Various functional properties of the P-wave evoked by preoptic stimulation, are discussed.

Animals↗
PubMedDate not supplied

[Participation of the neocortical and reticulo-hypothalamic apparatuses in the regulation of recurrent inhibition in the thalamic relay nucleus].

In acute experiments on cats a study was made into the development of the field potential of the recurrent inhibition wave (P-wave) in VPL in response to the stimulation of the somatosensory cortex. It has been found that high-frequency stimulation of the posterior medial hypothalamus results in the reduction of the thalamic P-wave brought about antidromically and in a decrease of the number of waves in the series. The effect of stimulation of the posterior hypothalamus on the processes of recurrent inhibition in the relay thalamus is to a great extent mediated through mechanisms of the branstem reticular formation. It has been shown that the dynamics of amplitude characteristics of primary sensory responses in the VPL depends on the phases of development of P-wave in the nucleus. Functional switching off of the cortex by means of loci toxic action reduces the amplitude of P-wave produced by stimulation of a point of the poisoned cortex. Spatial non-coincidence between the topography of foci of maximal activity of primary thalamo-cortical responses and the foci of maximal influences of the stimulated cortex on recurrent inhibition in VPL points to the likely involvement of the neocortical apparatus proper in recurrent thalamic inhibition.

Animals↗
PubMedDate not supplied

[Autonomic support of the systemic response under conditions of operator visual-stress activities].

The parameters of functioning of muscular, cardiac-respiratory, vegetative and other systems in the organism of healthy persons engaged in the work connected with visual strength have been studied. The optimal limits of system response are determined and thus its realization is shown to be provided with the activation of vegetative regulation apparatus. The structure of the relations between the distinguished parameters is maintained even when new level of functioning is established. Initial activation of vegetative mechanisms is a leading factor of the further rearrangements of visual and somatosensory analyzers with the given kind of activity.

Adolescent↗
PubMedDate not supplied

[Role of the median forebrain bundle in organizing the electrical activity of the neocortex].

Bilateral coagulation of the forebrain medial bundle in the lateral hypothalamus enhances the formation of spontaneous spindles and facilitates the recruiting response in the neocortex. This combines with a defect of desynchronizing influences of the posterior hypothalamus and the concurrent dominance of synchronizing effects of the preoptic area (PA). PA stimulation enhances the slow wave and spindle activity in the ECoG of the intact brain. After disruption of PA connections with the bulbar synchronizing apparatus the stimulation effect is manifested only in enhanced spindle activity. It is assumed that in addition to hypnogenic influences which PA shares with the parasolitary apparatus, it maintains a definite level of cortical reactivity after the onset of sleep. Elimination of the orbito-frontal cortex, as well as PA coagulation, does not prevent the appearance of spindles in the ECoG of the preparation with an intersected medial bundle, only limiting them to some extent.

Animals↗
PubMedDate not supplied

[Effect of arousing and somnogenic effects on the hypothalamus on the space-time organization of the internal connections of the somatosensory cortex].

Evoked potentials arising in the somatosensory cortex in response to single local stimulation of a forepaw, were recorded in cats in a state of slow-wave sleep and strained alertness elicited by electric activation of the basal preoptic area and posterior hypothalamus. Structure of connections between cortical points was studied by values of responses' amplitudes by means of correlation and factor analyses. It has been found that the organization of functional connections within the somatosensory cortex is determined by several factors, sensitive to hypothalamic influences. The most specific organization for each state is revealed at the stage of completion of the positive-negative complex of the primary response, which combines with the highest plasticity of connection formation.

Animals↗
PubMedDate not supplied

[Participation of the preoptic area in the synchronizing and desynchronizing mechanisms of the brain].

The paper deals with spreading of the positive wave (P-wave), appearing in response to stimulation of the basal preoptic area (BPA) in the structures of meso-diencephalic and bulbar levels, predominantly involved into synchronizing and desynchronizing brain systems. It is shown that P-wave is mostly pronounced in the structures situated along the medial fascicle of the forebrain, its bilateral coagulation leading to changes in wave characteristics in the studied structures. Besides, after section of the medial fascicle of the forebrain pronounced inhibitory effects of the posterior hypothalamus on P-wave appearing in response to stimulation of BPA, are considerably weakened.

Animals↗