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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
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Nestbox provision is a technique used to increase nest-site availability for secondary cavity-nesting birds. However, little is known about the demographic consequences of nestbox provision in different habitat types. To assess how nestbox provision affects the density of hole-nesting birds simultaneously in two contrasting habitats, we compared the breeding density of Great Tits along transects without nestboxes with that in transects where nestboxes were provided. Although the initial density of breeders was considerably higher in the deciduous habitat than in the coniferous habitat, provision of nestboxes increased density by a similar number of additional pairs in each habitat type. Thus, the provision of nestboxes in managed coniferous forests may be as effective in increasing the breeding opportunities of cavity nesters as in deciduous stands. Moreover, previous research showed that pairs in deciduous habitat with nestboxes have consistently lower breeding success than those in coniferous habitat with nestboxes. It is possible that the addition of nestboxes in the preferred habitat increased density to such an extent that density-dependent effects became apparent. 相似文献
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The causes of the indefinite propagation of immortalized cell populations remain insufficiently understood, that hinders the research of such fundamental processes as ageing and cancer. In this study the interrelations between clonal proliferation and abnormalities of mitotic divisions in the immortalized cell line established from the mouse embryo were investigated with the aid of computerized microscopy of living cells. 3 mitoses with three daughter cells and 7 asymmetric mitoses which generated two daughter cells of conspicuously different sizes were registered among 71 mitotic divisions in the individual cell genealogy. Abnormal mitotic divisions either did not slow the proliferation in cell clones compared with progenies of cells that divided by means of normal mitoses or were followed by the acceleration of divisions in consecutive cell generations. These data suggest that abnormal mitotic divisions may contribute to the maintenance of the immortalized state of cell populations by means of generating chromosomal instability. 相似文献
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A. N. Kucher A. L. Danilova L. A. Koneva A. N. Nogovitsina 《Russian Journal of Genetics》2007,43(6):677-684
The distributions of surnames have been studied in 12 rural ethnic territorial groups of Sakha Republic (Yakutia). The populations studied are characterized by considerable accumulation of individual surnames, the surname spectra of representative of different ethnic groups living in the same area substantially overlapping. The random isonymy, migration index, surname diversity, and the surname distribution redundancy index display geographic and ethnic differences. The isonymy relationship coefficients calculated for representatives of individual ethnic groups (Yakuts, Evens, and Russians) and for total populations of the settlements studied are determined by the geographic distances between the compared populations and the intensity of migrations. 相似文献
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Elena Yu. Bragina Evgeny S. Tiys Maxim B. Freidin Lada A. Koneva Pavel S. Demenkov Vladimir A. Ivanisenko Nikolay A. Kolchanov Valery P. Puzyrev 《Immunogenetics》2014,66(7-8):457-465
Co-existence of bronchial asthma (BA) and tuberculosis (TB) is extremely uncommon (dystropic). We assume that this is caused by the interplay between genes involved into specific pathophysiological pathways that arrest simultaneous manifestation of BA and TB. Identification of common and specific genes may be important to determine the molecular genetic mechanisms leading to rare co-occurrence of these diseases and may contribute to the identification of susceptibility genes for each of these dystropic diseases. To address the issue, we propose a new methodological strategy that is based on reconstruction of associative networks that represent molecular relationships between proteins/genes associated with BA and TB, thus facilitating a better understanding of the biological context of antagonistic relationships between the diseases. The results of our study revealed a number of proteins/genes important for the development of both BA and TB. 相似文献
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Lars E. Holmer Svetlana P. Koneva Leonid E. Popov Ajdar M. Zhylkaidarov 《Pal?ontologische Zeitschrift》1996,70(3-4):481-495
A new middle Ordovician fauna including conodonts and brachiopods is described from the early Llanvirn Zhyrykaus Formation, Malyi Karatau Range, southern Kazakhstan. The fauna includes the lingulate brachiopodsHyperobolus fragilis n. sp. andTalasotreta apollonovi n. gen. n. sp., as well as the conodontsCordylodus? cf.horridus, Drepanoistodus? sp.,Erraticodon sp.,Parapaltodus simplicissimus, Prioniodus (Baltoniodus) sp.,Protopanderodus cf.varicostatus, andWalliserodus sp. s. f. It represents the first record of Llanvirn conodonts and Ungulate brachiopods from southern Kazakhstan. 相似文献