Search PubMed⌕ Search

Biomedical subjects

A V Nemtsov

Publications and source records attributed to A V Nemtsov.

At least 37 records · Page 2Linked to original sources
PubMed1979

[Structure and correlation of "fast" and "slow" background impulse activity of visual cortex neurons].

Background and optically modified impulse activity of neurons in visual cortex of unanaesthetized rabbits was analyzed. By means of joint interval histograms it was shown that neurons can be distinguished by the ratio of burts (intervals to 15-40 ms) and extraburst activity and by the shape of transition from one from of activity to another. The extraburst activity comprises 63% of impulses and its ratio to bursts of 2 or 3 and more impulses was 27:3:1. Burts impulse distribution showed a relative stability of timing pattern within bursts and small number of burst impulses (2.4 on the average). Bursts of 3 and more impulses (3.6 on the average) are not rhythmical and 79% of them contained long intervals (18.6 +/- 2.4 ms) before the shortest one (7.9 +/- 0.9 ms). Optical stimulation resulted in bursts containing core impulses, shorter intervals and beginning with the shortest interval in most neurons. This may testify to the increase of the EPSP steepness and amplitude. 20% of cortical neurons showed background bursts containing more impulses and shorter intervals in comparison with evoked bursts.

Animals↗
PubMed1975

[Effect of neuroleptics of the phenothiazine series on the impulse activity and ultrastructure of the cortical neurons of rabbits].

Experiments on rabbits showed that chlorpromazine given in a dose of 5 mg/kg produced a disaggregation of polysomes, dilatation of the cysterns of the endoplasmic reticulum, hypertrophy of the Golgi apparatus and swelling of the mitochondria in the majority of the cortical neurons. To these ultrastructural changes corresponded the inhibition of the pulse activity of the nerve cells. In difference from chlorpromazine, trephthazine given in the same dose caused a thickening of the matrix of a part of the neurons, accompanied by an increase in the pulse activity of a group of the cortical cells (28%) under the effect of triphthazine. The established changes in the pulse activity and the ultrastructure of the neurons are regarded in association with the differences in the spectrum of the psychotropic activity of the two neuroleptics--phenothiazine derivatives.

Animals↗
PubMed1975

[Effect of triftazin on the transmission of excitation in the brain of the rabbit under the prolonged administration of the preparation].

Experiments were conducted on awake rabbits to which trifluoperazine was given daily for 2 weeks in a dose of 1 mg/kg a day; a study was made of the reaction of the cortical neurones in response to the electrostimulation of its adjacent areas. In measuring the dispersions of the poststimular histograms it was found that under the effect of trifluoperazine there occurred a reduction of the value and the duration of the responses of the cortical neurons after the infliction of stimulation. The effect obtained after the administration of trifluoperazine was regarded from the point of view of aggravation of the signal conduction in the neuronal reticula.

Amitriptyline↗
PubMedDate not supplied

[Classification of cortical neurons according to the character of their background impulse activity].

The method of basic components and cluster analysis was used to classify 75 units in the visual cortex of alert rabbits, proceeding from the empiric form of distribution of interspike intervals (DII), the mean frequency of impulsation and the relative number of intervals up to 500 msec. They were classified into nine groups containing from two to twelve units. Besides the cues, used as a basis for classification, the groups of units also differed in the structure of burst activity, the correlation of adjacent intervals and the ratio between the short (up to 20 to 60 msec) and long intervals. The latter served to make suggestions on the genetic affinity of bimodal DII to those with a bend on the waning after the maximum, and on the nature of formation of high frequency bursts and intervals exceeding 20 to 60 msec.

Animals↗
PubMedDate not supplied

[The character of the background spike activity of cortical neurons under the influence of psychotropic drugs].

A comparison was made on alert rabbits between the nature of spike activity of normal cortical neurones and of those after a two-week daily administration of neuroleptics, namely chlorpromazine, trifluoperazine and haloperidol in 1 and 5 mg/kg doses. The groups of neurones did not differ in the mean frequency of firing. However, the use of the main components method and of cluster analysis showed considerable differences between neuronal activity following the action of neuroleptics and that in control animals. The most common effect of neuroleptics consisted in a reduction of the number of low frequency neurones with burst discharges and small dispersion of distribution of interspike intervals. Trifluoperazine and especially haloperidol differed from chlorpromazine in that they brought about an appearance of cortical neurones for which the distribution of interspike intervals had an almost symmetrical form and a mode of 80--170 msec. After the action of haloperidol about a third of the neurones had a mode up to 10 msec. An assumption has been made that the major effect of trifluoperazine and haloperidol consists in an increase in the reverberative activity of the brain.

Animals↗
PubMedDate not supplied

[Regional indices of alcoholic poisonings and alcoholic psychoses].

Interrelations of phenomena preconditioned by alcohol consumption were the starting prerequisite of the case study. The annual lethality rates due the to alcohol poisonings (AP) and alcoholic psychosis (APS) morbidity were investigated in 77 Russia's regions during 1991-1999, when the alcohol consumption used to be dynamic in the country--a sharp growth in 1991-1994, a drop in 1995-1998, and a new increase in 1999. The correlation of studied phenomena was observed only in 33 regions. The ratio of AP level to APS level varied in different regions and during different time periods from 50-fold AP prevalence to 65-fold APS prevalence. The distribution of APS indices was normal, while the distribution of AP deviated from the norm towards a higher dispersion. Two etalons were made use of, i.e. one for AP and the other for APS, to assess the differences between the AP and APS indices. APS differed from the appropriate etalon by far less versus AP. A list of regions with respect for deviations of APS and AP indices was compiled. A conclusion was made to the extent that consciously or unconsciously the postmortem diagnoses of AP were concealed in a majority of Russia's regions; APS were not registered in full either. However, the latter reflect better the alcohol-related situation in regions versus AP.

Alcoholic Intoxication↗
PubMedDate not supplied

[Use of the PFK-01 psychophysiologic unit in the diagnosis of alcoholic patients].

Alcoholic patients were tested on production of short time intervals by means of psychophysiological computer-controlled unit PFK-01 after the dedicated software was completed. Subjective time rate was related to the emotional state of patients. A tendency towards hypoproduction, i.e. towards acceleration of subjective time rate, was associated with the state of anxiety.

Adult↗