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21.
Individual characteristics of animal behavior can serve a prognostic parameter of predisposition to use of alcohol. The goal of the work was to study dynamics of formation of preference of alcohol at early stages in the process of forced alcoholization in male and female rats as well as the accompanying changes in behavior parameters. For 3 months, the rats were submitted to the forced alcoholization with 10 % ethanol. Each week the rats were tested in the "two-glass trial". Individual peculiarities of all animals were evaluated prior to, after 6 weeks, and after the end of the experiment with aid of the "open field test" and "Suok-test". Results showed that the male rats demonstrating by the end of the experiment the significantly higher level of the alcohol preference, at the initial stages of the forced alcoholization demonstrated the significantly lower preference as compared with the remaining ones. These rats also showed the lower levels of the motor and exploratory activities before alcoholization as compared with control. On the contrary, the individuals that by the end of the experiment did not differ from control by the level of the alcohol preference demonstrated prior to alcoholization in the "Suok-test" the higher anxiety level. In female groups, no statistically significant differences were observed both in parameters of the motor and exploratory activities and in the anxiety level in both tests. Thus, in male rats, the prognostic parameter predicting formation of the abuse can serve the degree of alcohol preference at the initial stages.  相似文献   
22.
Specificity of the structure of gene pools of different ethno-territorial groups of the human population can underlie the epidemiological features of the spread of tuberculosis (TB) and the structure of the genetic component of the susceptibility to the disease. The variability of 62 genetic variants potentially associated with the risk of the development of TB in the Russian population of the city of Tomsk has been studied and the differentiation of various ethno-territorial groups of the world by these markers has been assessed. The studied sample comprised 445 Russian residents of the city of Tomsk without bronchopulmonary pathology. For comparison, the data on the variability of the genetic markers of interest in 26 populations from the 1000 Genomes Project was involved. In the Tomsk population, only the ancestral allele was found for seven of the 58 SNPs studied; the allele frequencies for 36 markers were within the limits of the values seen in other European populations; for 12 SNPs, the observed frequencies were closer to populations with a significant Mongoloid component. By the total of the SNPs, the Tomsk population, despite the geographical distance from the rest of the European populations, did not differ from them (in genetic distances and Gst statistics), although it had some features of the gene pool. Intergroup differentiation of the world populations by these SNPs reflects mainly interracial differences. The greatest differences in the genetic structure between the studied populations were seen for the markers localized in intergenic regions. Statistically significant differences were found when comparing the levels of the average expected heterozygosity between groups of “L4 carrier populations” of mycobacteria and “non-L4” populations, which indicates the impact of the prevalence of different pathogenic lineages of M. tuberculosis on the formation of population specificity of the allelic frequencies.  相似文献   
23.
The sequencing of the nucleotide sequences of the mrjp3 repetitive region (mrjp3 microsatellite locus) in Siberian honeybees was carried out. A high similarity of the studied nucleotide sequences (≥99% identity) with reference sequences was observed, which indicates a high conservation of the mrjp3 repetitive region in different Apis mellifera subspecies.  相似文献   
24.
In the wild-type strain of methylotrophic yeast Pichia pinus diauxic growth is observed during cultivation in medium containing a mixture of methanol and ethanol: firstly, slow phase of ethanol utilization is revealed and, secondly, a fast phase of methanol consumption is shown. Diauxic growth is observed also in ecr1 mutant, impaired in ethanol-induced catabolite repression of methylotrophic metabolism enzymes, but the order of utilization of the alcohols is inverted in this mutant. Such succession of alcohols utilization in both strains correlates well with the sequence of synthesis of microbody enzymes which catalyze key reactions of C1- and C2-metabolism. On the contrary, simultaneous utilization of methanol and ethanol from the mixture, as well as synchronous synthesis of both peroxisomal and glyoxisomal enzymes is observed in adh1 mutant which has reduced alcohol dehydrogenase activity. The strong differences between the wild-type strain and adh1 mutant were observed also in the kinetics of specific activity changes for C1-metabolizing enzymes, localized in cytosol. In the wild-type strain during growth on methanol and ethanol mixture such changes correlate with the sequence of alcohol utilization. At the same time, in adh1 mutant the activities of formaldehyde dehydrogenase and formate dehydrogenase during the growth on the alcohols mixture are as high as during growth on methanol only, but the activity of dihydroxyacetone kinase is as low as under the growth on ethanol and is lower than on methanol.  相似文献   
25.
Molecular Biology - The pandemic of coronavirus disease 2019 (COVID-19) warrants the identification of factors that may determine both risk and severity of infection. The factors include microRNAs...  相似文献   
26.
Russian Journal of Genetics - Histamine is a biologically active substance of local effect, but is involved in the regulation of different processes in the body, including the pathogenesis of...  相似文献   
27.
The genetic demographic structure of 12 rural populations from eight uluses of Sakha Republic (Yakutia) has been analyzed. The ethnic, sex, and age composition of the population and the reproductive parameters of women that have completed and have not completed the reproductive period are reported. Crow's indices have been estimated in representatives of three indigenous ethnic groups (Yakuts, Evens, and Evenks).  相似文献   
28.
The population dynamics and changes in the sex and age structure of the Shor populations of four rural district municipalities of Tashtagolskii raion of Kemerovo oblast (Kyzyl-Shorskii, Ust-Anzasskii, Ust-Kolzasskii, and Ust-Kabyrzinsskii) with time have been analyzed. The Shor populations have been found to have contained a high proportion of people under 18 years of age during two periods, 1940–1955 and 1970–1975 (38.12–46.38 and 40.98–54.97%, respectively). However, the population reproduction pattern changed into the “reduced” one in all the municipalities studied by the early 2000s. Although there are some regional variations, a common trend towards rural population aging has formed: the man age in the Tashtagolskii raion population has increased by 7.52 and 6.94 years for men and women, respectively, during two generations; the natural sex ratio has been disturbed in both the prereproductive and reproductive populations. The total population size and effective reproductive size have decreased in three out of the four rural subpopulations studied.  相似文献   
29.
Kucher AN  Soltobaeva ZhO 《Genetika》2004,40(11):1540-1548
The genetic demographic parameters of rural populations of Kyrgyzstan have been studied. The rural population of Kyrgyzstan has the following demographic characteristics: (1) it is demographically young (the population mean age is 25-28 years); (2) the sex ratio in reproductive age groups is unfavorable; (3) the fertility is high (5.78-7.68 pregnancies and 4.27-5.20 surviving children per woman of postreproductive age; (4) interethnic marriages are rare (1.0-5.9%), whereas consanguineous marriages are frequent (1.4-12%); (5) Crow's indices are relatively low (I(tot) = 0.24-0.29, I(m) = 0.05-0.13, I(f) = 0.14-0.22); and (6) both male and female contributions of different regions of the republic make unequal contributions to the gametic structure of the population, with the gametic structure varying from generation to generation. Demographic parameters vary in rural populations of different geographic regions and with different ethnic compositions.  相似文献   
30.
Information on the sex, age, and ethnic compositions; reproductive parameters; intensity of natural selection (Crow's indices); and surname diversity of three rural populations (the Byadi, Dyupsya, and Cheriktey villages) of the Ust-Aldan ulus (district) of Sakha Republic (Yakutia) has been analyzed. The rural Yakut population of the Ust-Aldan ulus is demographically young (the mean age 25–31 years) and characterized by low outbreeding, unfavorable sex ratio in both prereproductive and reproductive ages, and high fertility (3.58–5.45 children surviving until the reproductive age per woman that has completed the reproductive period), although the actual reproductively active period is shorter than half its physiological duration. In the structure of index of total selection, the differential-fertility component is considerably greater than the differential-mortality component (I tot = 0.625, I m = 0.093, and I f = 0.487). In the villages studied, some surnames are accumulated (45–65% of the population have five most frequent surnames), which determines the low surname diversity ( = 11.62–25.19) and high random isonymy (I r= 0.0391–0.0823).  相似文献   
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