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41.
Three separate and reproductively isolated populations living at present in boreal forest and tundra area in Eastern Siberia were studied. Blood groups (AB0, MNSs, Rhesus, Duffy, P. Diego), immunoglobulin allotypes--G1m (z, a, x, f), G3m (b, b0, b1, b3, s, t), Hp, Tf, PGM1, AcP, 6-PGD were tested in blood samples obtained from total 570 individuals. Analysis of covariance and variance matrices containing gene frequencies of the Nganasans, Reindeer Chukchi, the Yugaghir and the Evens has revealed major aspects of regional genetic structure which is in good accordance with regional history and geography. 相似文献
42.
O L Posukh V P Wiebe R I Sukernik L P Osipova T M Karaphet M S Schanfield 《Human biology; an international record of research》1990,62(4):457-465
Three territorial subgroups of reindeer breeders, fishermen, and fur hunters living under conditions of partial isolation in remote parts of the Yakut ASSR, have been investigated with respect to polymorphic genetic systems. Analysis of covariance matrices containing allele frequencies in an array of 12 loci for a large sample of Evens, Nganasans, and reindeer Chukchi indicates that the genetic relationships support known phylogenetic, linguistic, and historical events. 相似文献
43.
The formation of "early" (5-8 days) and "late" (12-14 days) colonies in spleen of lethally irradiated syngeneic or hybrid recipients after transplantation of bone marrow cells has been studied. The differentiation pattern did not depend on bone marrow cell donor's genotype and the donor-recipient combination. Erythroid to granulocyte colonies ratio (E/G) equals 2. Change of direction of bone marrow colony-forming units (CFU) differentiation has the same pattern at different stages of colony-formation. Under the influence of antigen-stimulated lymphocytes the granulopoiesis (E/G 0.3-0.5) dominanted. The thymectomy of adult animals leads to a predominant formation of erythroid colonies (E/G 3.5-5.1). When T-immunodeficiency is reversed with syngeneic lymphocytes, the differentiation of CFU is normalized at all stages of colony-formation. The process of differentiation of haemopoietic precursors, that form "early" and "late" colonies, is under T-lymphocyte control. 相似文献
44.
No colonies were found in the spleen at "early" times (7-8 days) after irradiation of mice with doses of 8-9 Gy, while at "later" times (after 15 days) a confluent growth of the colonies was observed. The endogenous splenic foci of haemopoiesis of the "late" type were characterized by the preferable growth of granulocytic colonies. 相似文献
45.
46.
A A Bulatov T A Osipova S M Terekhov E T Sazina Iu A Pankov 《Biokhimii?a (Moscow, Russia)》1983,48(8):1305-1310
Some new evidence on the biological activity of somatotropin fragment 77-107 is given. This fragment was prepared from whale somatotropin by tryptic hydrolysis. Beside the previously established ability of the hormone to increase the width of the tibial epiphyseal cartilage in hypophysectomized rats ("tibia" test) two other properties of the fragment indicative of its growth-promoting activity were established. The fragment enhances DNA biosynthesis in cultured human fibroblasts and increases the somatomedin content in blood serum of hypophysectomized rats. However, the fragment unlike the native hormone does not exert any metabolic action on adipose tissue "in vitro", i. e. does not stimulate the nonesterified fatty acid release into the medium. A comparison of the biological activity spectrum of native somatotropin and of its fragment 77-107 suggests that the biochemical information required for the realization of a prolonged growth-promoting effect and a relatively rapid action of the hormone on lipid and carbohydrate metabolism is contained in different parts of the polypeptide chain. 相似文献
47.
Blood groups, immunoglobulin allotypes, serum proteins and red cell enzymes were tested in four populations of Asiatic Eskimos. 12 of 16 gene loci studied were found to be polymorphic. Analysis of covariance and variance matrices for gene frequencies of 8 Bering Sea populations revealed major aspects of regional genetic structure. Regression of average heterozygosity on genetic distance from centroid permitted us to interpret it in the light of counterbalancing action of systematic and non-systematic pressure. Analysis of R matrix containing gene frequencies for both Eskimo and Chukchi populations revealed two different clusters - more heterogeneous Eskimo cluster and less heterogeneous Chukchi cluster. Good fit was observed between regional genetic structure, history and geography. 相似文献
48.
G1m (z, a, x, f) and G3m (g, b0, b1, b3, b5, s, t) allotypes were tested in 1079 Chukchi inhabitants of interior Chukotka and adjacent Kamchatka. Genetic variation at this particular locus is provided by the presence of three haplotypes, namely, za;g, zax;g and za;bO35st, revealed with mean frequencies of 0.748, 0.089 and 0.154, respectively. Traces of Caucasian Gm (f;bO135) haplotype were observed in 9 of 10 populations studied. Judging from its frequency in the whole group (0.009), European admixture in Reindeer Chukchi did not exceed 1.3%. Analysis of covariance and variance matrices containing gene frequencies for 11 polymorphic loci revealed the aspects of genetic structure. Simultaneously, the action of systematic versus nonsystematic pressure was also evaluated and interpreted in the light of historical and ecological events. 相似文献
49.
Summary A Samoyed-speaking group of fishers, hunters, and deer breeders numbering 1500 in total has been investigated. Seven territorial subgroups were examined with respect to 15 genetic systems. The presence of A2, cde, CwDe, Kpa, AK2, pc, Gmfb, and Gmfnb genes or haplotypes in low or moderate frequencies was observed. An unexpected finding was a deleted Gm(-;n;gb) phenotype in three siblings.Significant local genetic heterogeneity was observed with regard to AB0, Rh, Tf, PGM1, 6-PGD, and Gm systems. The summed genic heterogeneity was found to be highly significant (
132
2
=663.70, P< 0.001). Mean Fst was equal to 0.0228, reflecting variation among subpopulations dispersed in the forest-tundra area and living under conditions of partial isolation. 相似文献
50.
5-week old rats underwent a partial hepatectomy (2/3 of the liver was removed). The operated rats were repeatedly injected hydroxyurea, within 9-24 or 12-24 hours following operation. Proliferation of hepatocytes and non-parenchymal cells in the regenerating liver was studied. Five or six injections of hydroxyurea increased the labelling index of hepatocytes up to 62.5% and induced proliferation of bile duct cells significantly. 相似文献