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Summary Blood samples from 403 Reindeer Chukchi of inland Chukotka, and 100 samples from Chaplin Eskimos of the Chukot Peninsula were tested for G1m (z,a,x,f), G2m (n), G3m (g,b0,b1,b3,b5,s,t), and Km (1) allotypic determinants. An apparent affinity between the Chukchi and the Eskimos could be inferred from similar frequencies of the two common haplotypes, Gmza;g and Gmza;bst, and from very similar frequencies of the Km1 allele. However, none of the Eskimos had Gmzax;g, though it occurred at a low or moderate frequency in the five Chukchi populations studied. It is assumed that Chukchi can be distinguished from adjoining Eskimos by the same G1m (x) outlier, that has been considered as a taxonomic marker useful in differentiating between Eskimos and American Indians. Comparison of North Asian and North American populations with respect to the array and frequencies of Gm haplotypes and the Km1 allele, supports the hypothesis of a nonrandom distribution of the Gmza;bst and Km1 on both sides of the Bering Strait.  相似文献   
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The results of detection of phosphatases with different substrates in the cells forming steroid hormones in ovaries, testes and adrenals of newborn seals, ovaries of adult seals and adrenals of adult rabbits, dogs and man were compared. The first group of substrates includes sodium glycerophosphate, glucose-1-phosphate, nitrophenylphosphate (Gomori's sulfide method). The second group includes naphthol phosphates AS-BI, AS-MX and AS-BS, whose hydrolysis is determined by simultaneous and successive azocoupling with diazotized benzidine and stable diazotates by fast blue and fast cherry-coloured. Detection of phosphomonesterases in the cells forming steroid hormones with these two groups of substrates gives absolutely different results which are presented in the table. These results are thought to be associated with presence of the isoenzyme, intensively splitting azotholphosphates, but inhibited by the diazonium salt. This isoenzyme is found mainly in the cells producing steroid hormones.  相似文献   
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This is the first study to obtain a high-purity luciferase from the fungus Neonothopanus nambi biomass that is suitable for subsequent sequencing.  相似文献   
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The first study on the frequencies of polymorphic variants of the GSTP1 gene encoding glutathione-S-transferase P1 in Tundra Nenets and Nganasan populations was performed. The subject of the study was the single nucleotide polymorphisms rs1695 (Ile105Val substitution in the protein sequence) and rs1138272 (Ala114Val substitution) that had previously been shown to be associated with cancer and other multifactorial diseases. The data for Tundra Nenets of the Yamalo-Nenets autonomous okrug, Nganasans of the Taimyr Peninsula, and Russian residents of the Northern Siberia were compared. The frequencies of the mutant 105Val and 114Val variants were 10.8% and 0.8% in Nganasans, 23.7% and 4.8% in Nenets, and 35.8% and 9.1% in Russian population samples, respectively. The differences within all pairs of populations were significant for each allele. These differences may characterize the population-level susceptibility to cancer and other multifactorial diseases.  相似文献   
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The article deals with the influence of meteorological factors on the activity of the taiga tick Ixodes persulcatus Sch. in the city of St. Petersburg and its environs. The results of correlation analysis of meteorological data (21 parameters) and tick collection data for 1980-2012 demonstrated a linear dependence between 11 meteorological parameters and the mean abundance of ticks. Factor analysis reduced dimensionality down to 3 parameters: the accumulated temperatures higher than +5.0°C, the annual sum of daily precipitation amounts greater than 5 mm, and Selyaninov’s hydrothermal coefficient. It was shown that, while the mean abundance of active ticks in the studied territories tended to decrease, correlation between the abundance of ticks and meteorological parameters varied significantly in both intensity and direction depending on the microclimatic features of the collection sites. At low annual variation of the mean tick abundance, the methods of collection can significantly affect the results of statistical analysis. This fact should be taken into account when predicting both the timing and the intensity of the epidemiological season.  相似文献   
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The structure of fungal oxyluciferin was determined, the enzymatic bioluminescence reaction under substrate saturation conditions with discrete monitoring of formed products was conducted, and the structures of the end products of the reaction were established. On the basis of these studies, the scheme of oxyluciferin degradation to the end products was developed. The structure of fungal oxyluciferin was confirmed by counter synthesis.  相似文献   
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