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E V Petrova

Publications and source records attributed to E V Petrova.

At least 19 recordsLinked to original sources
PubMed2005

Actions of pulsed ultra-broadband electromagnetic irradiation on the EEG and sleep in laboratory animals.

Irradiation of animals with ultrashort impulses of ultra-broadband magnetic irradiation with an impulse repetition frequency of 6 Hz for 1 h induced changes in the spectral composition of cerebral cortex electrical activity in rats, measured over the 5 min immediately after irradiation, as compared with controls. In particular, there was suppression of frequencies close to the impulse sequence frequency, along with a decrease in interhemisphere coherence. Continuous recording of polygrams for 22 h from rabbits after irradiation revealed a "delayed" effect--a significant increase in paradoxical sleep, starting 16 h after the end of irradiation and persisting to the end of the recording period. It is suggested that irradiation has a direct action both on the mechanisms of generation of the theta rhythm (septohippocampal) and on the system controlling circadian rhythms (the suprachiasmatic nucleus-epiphysis system).

Acoustic Stimulation↗
PubMed1996

Generalized absence epilepsy and catalepsy in rats.

Adult WAG/Rij rats are considered adequate genetic models for human generalized absence epilepsy. Rats of this strain of 8, 12, and 18 weeks old and age-matched control Wistar rats were exposed to sound stimulation. After offset of stimulation, all WAG/Rij rats showed cataleptic or even cataplexic reactions, which could persist for up to 20 min. Age effects could be demonstrated. None of the Wistar rats showed cataleptic reactions. Electroencephalographic studies in WAG/Rij rats of 21 weeks showed that spike-wave discharges were abundantly present in the background electroencephalogram prior to sound stimulation. Age-matched Wistar rats had almost no spike-wave discharges. Spike-wave discharges in WAG/Rij rats disappeared during sound stimulation and were then increased compared to the prestimulation and stimulation periods. The electroencephalogram during the cataleptic state was also characterized by the presence of large amplitude 2 Hz waves, interspersed with spike-wave discharges. The data suggest that the cataleptic state can be elicited in genetically epilepsy-prone rats. The youngest WAG/Rij rats showed no spike-wave discharges during the cataleptic state. In all, the data suggest that epilepsy-prone animals are sensitive for catalepsy at an age at which the EEG signs of generalized absence epilepsy are not yet manifest.

Animals↗
PubMed1996

Biochemical properties and excretion behavior of repressible acid phosphatases with altered subunit composition.

Yeast repressible acid phosphatase (rAP) is the oligomeric extracellular enzyme encoded by the three structural genes PH05 (p60), PHO10 (p58) and PHO11 (p56). We examined the ability of acid phosphatases formed by various subunit combinations to be excreted into the medium. Plasmids with repressible acid phosphatase structural genes under control of the yeast glyceraldehyde-phosphate dehydrogenase (GAP) promoter were constructed to obtain constitutive expression of acid phosphatase, and yeast strains with disruptions in PHO5, PHO10 and PHO11, respectively, were used to generate mutants expressing single genes or specific gene combinations. EndoF treatment of acid phosphatases, produced by these strains, followed by SDS-electrophoresis in combination with densitometry techniques revealed that the ratio p60/(p56 + p58) among structural polypeptides in extracellular enzyme is constant and equals to 6.0. A study of acid phosphatases formed by single type subunits was undertaken. Expression products of PHO5, PHO10 and PHO11 genes were isolated from the culture medium. The specific activities of the enzymes were found to be 33, 2 and 2 mM x mg-1 x min-1, respectively. The values of Mr estimated by HPLC chromatography for the enzymes encoded for by the genes PHO5, PHO10 and PHO11 and SDS-polyacrilamide gel electrophoresis data suggested an oligomeric organisation of the enzymes. Isoelectric focusing in polyacrylamide gel with immobilised pH gradient followed by activity staining yielded numerous sharp bands of homopolymeric acid phosphatases forms being different in their pI. The kinetic characterisation of the enzymes revealed differences in Km values, sensitivity to temperature inactivation, inhibition by orthophosphate and the effect of pH on the enzyme activity.

Acid Phosphatase↗
PubMed1996

[International concept of antituberculous care organization for the Tomsk region's population].

The priorities of the international concept of organization of antituberculous care to the population of the Tomsk Region are as follows: detection of bacillar patients and their short-term intensive chemotherapy by the WHO categories; formation of a 6-month reserve of tuberculostatics and complete control over patients' drug use; diagnosis of diseases by the general medical network for patients' referrals by introducing indications for clinical examinations for tuberculosis and sputum tests for Mycobacterium tuberculosis, fluorographic studies of only risk group populations; tuberculin diagnosis among children aged 1-14 years from risk groups; BCG vaccination of the newborn and revaccination at the age of 6-7 years. Resource mobilization is essential. This includes: strengthening of basic service institutions and centralization of its structures; fund saving by reasonably reducing the beds in sanatoria and hospitals; extension of therapeutical and diagnostic services at the outpatient stage of a follow-up; decrease in the length of patients' medical examinations and in the number of groups registered at a tuberculous dispensary; intensification the work of a phtx11p4trist and a nurse with their salary increases.

BCG Vaccine↗
PubMed1991

[Transformation of semantic concepts in alcoholism].

As many as 20 alcoholic patients and 20 healthy men were subjected to a free associative experiment with the stimuli-words such as "wife", "chief", "shop", while the word "pencil" was used as neutral control. In the patients, the words "chief" and "wife", in particular, evoked highly predominant emotional associations due to the negative characteristics of the chief and positive ones of the wife, her general human qualities and attitude toward her husband. The latter association was compensatory in nature, reflecting the importance of the wife theme for alcoholic patients. As compared to the healthy persons, the degree of transformation of the meanings of the stimuli-words in the patients can serve as an indicator of the importance of the meanings "wife", "chief", "shop" and "pencil" (zero transformation). The data obtained indicate that the psychosomatic approach makes it possible to rearrange the semantic structure of the patients transformed personality, to reveal its so-called "hot points" which may require psychocorrection.

Adult↗
PubMed1984

[Intestinal peptidase content of the mucous coat of the small intestine in dogs].

The content of leucine aminopeptidase, cathepsins B and D was measured in the mucous coating of the small intestine and duodenal juice of adult fistula dogs. It was shown that inhibitory assay was mandatory for measuring the content of intestinal peptidases. The authors discuss the possibility of hydrolysis of food substrates in the parietal layer of the mucous coating by proteolytic enzymes of both intestinal and pancreatic origin.

Animals↗