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51.
Some genetical demographic characteristics of population of Ashkhabad city were studied by direct interviewing of women aged over 18 years. The influence of urbanization on the basic genetical-demographic indices was found, the indices being essentially different from those of rural population studied elsewhere. Analysis of intensity and the structure of marriage migrations showed considerable ethnic subdivision in Ashkhabad population and stability of marriage policy in an every ethnic group. The level and structure of inbreeding as well as positive marriage assortativity are of the same order as in the Turkmen rural population.  相似文献   
52.
The study on the nature of distribution of certain mendelian markers aimed at specifying their role in determination of rheumatoid arthritis disease was carried out, based on the material from the Family Data Bank of the Department of Epidemiology and Genetics of the rheumatic diseases in this institute comprising data on 200 families of patients with definite rheumatoid arthritis (RA). Antigens of HLA-system (the loci A, B, DR), ABO blood groups, Rh, MN and P, phenotypes of acid erythrocyte phosphatase and the types of haptoglobin were studied. Based on the data from this and the previous studies, it is established that the steadiest deviations of the RA patients groups from the general population concerned the frequency of HLA A11, B12, B27 and DR4, blood group P and phenotypes of the acid erythrocyte phosphatase. When using additional controls--a group of healthy mothers of women-probands from the families with the type of marriage "healthy x healthy", and analysing some pair combinations of the HLA system antigens, it was demonstrated that the most clearly their role in formation of the disease display the antigens DR4, and in their absence--DR3, and B12, whereas accumulation of A11 and B27 depended on the presence of other antigens of HLA loci--A and B. Taken together, these data may imply that genetic markers under study serve, when in certain combinations, as "modifiers" of the major gene, or, in a general case, of major genes of multifactorial disease affecting its appearance and clinical manifestations.  相似文献   
53.
The study on the nature of genetic determination of the definite rheumatoid arthritis (RA) and its forms was carried out, based on the material comprising clinical data on 189 probands and their 1st and 2nd degree relatives (713 subjects) which is contained in the computer Family Data Bank at the Department of Epidemiology and Genetics of this institute. The heritability coefficient "in narrow sense" (80%) obtained within the framework of the multifactorial threshold model confirmed once more important role of genetic factors in the appearance of the disease. The study of genetic heterogeneity within the framework of the Ch. Smith's and T. Reich's models failed to reveal any independent genetically RA forms. An assumption of the essential role of the genes localized in the X chromosome, based on diverse susceptibility of sexes, received no conformation. It has been shown that the RA distribution in the population and families may well be described by means of a variant of the single autosomal two-allele locus model with incomplete and differentiated for two sexes penetrance. The model parameters obtained, a particular penetrance of the mutant homozygote in both sexes equalling 100%, and penetrance of the normal homozygote equalling 0 in men and reaching 0 (0.028%) in women testify to a very essential influence of the major gene on determination of RA.  相似文献   
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Sensitivity to II antibiotics of 80 strains of M. hominis isolated from patients with various inflammatory processes of the urogenital tract was studied by the method of suppressing the metabolic activity. Inhibition of the arginine metabolism of mycoplasma was used as a test for determination of the growth suppression. All the strains tested were highly sensitive to tetracycline and lincomycin. Kanamycin and neomycin were less active against M. hominis. All the strains tested were resistant to erythromycin, oleandomycin, ristomycin, novobiocin and streptomycin. The inhibitory effect of tetracycline and lincomycin on M. hominis decreased by the 5th day.  相似文献   
57.
Activity of lysozyme in the blood serum and leucocytes was determined. The experiments were carried out on albino unbred rats weighing 170 to 200 gm. Benzylpenicillin and oxacillin were administered intramuscularly in doses of 500000 Units/kg or 20000 gamma/kg once every 24 hours for 2, 4 and 6 days. The activity of lysozyme was determined by the turbidimetric and agar-diffusion methods. It was found that the activity of lysozyme in the leucocytes increased by the 5th day accompanied by a simultaneous decrease in its level in the serum followed by reaching the initial values. The data are indicative of the fact that the use of antibiotics in mega-doses is not contraindicated from the point of view of their effect on lysozyme activity.  相似文献   
58.
The effect of palladium and platinum salts (K2PdCl4, K2PtCl4) on bacteriophage F4 and its isolated DNA in genetic transformation is investigated. Both compounds efficiently inactivated the phage and decreased the transforming activity of donor DNA. The palladium salt exhibited the higher activity. The palladium compounds inhibited the transforming activity of native donor DNA to a greater degree. No difference was observed in the degree of inactivation of the transforming activity of native and denatured DNA under the effect of platinum salt. It is suggested that the difference in the transforming activity of donor DNA treated with the tested compounds reflect the pattern of their interactions with nucleic acids.  相似文献   
59.
A series of fatty acid ethyl esters ranging from C14 to C24 was isolated from a hexane extract of the liverwort Conocephalum conicum, these esters accounted for 77% of the extract. The ethyl esters consisting of even-numbered fatty acids were predominant and ethyl palmitate was the major constituent.  相似文献   
60.
The intra- and extracellular concentrations of cyclic adenosine monophosphate (cAMP) in cell line CHO-K1, sensitive (clone 773) and resistant to cytotoxic action of ethidium bromide (EBr), colchicine (Cr) and actinomycin D (ADr), as well as the amount of cAMP in response to isoproterenol, 10% serum and ethidium bromide (EB) in these cells were studied. The increased level of cAMP in EBr- and, Cr-cells, and the decreased one--in ADr cells was found as compared with sensitive cells. The amount of cAMP extruded in the surrounding medium was lower for EBr- and Cr-cells and higher for ADr-cells, in comparison with sensitive cells. All the variants of resistant cells were characterized by a less intensive but a longer reaction for isoproterenol, as compared with sensitive cells. In all the investigated variants 10% serum induced a remarkable increase in the intracellular cAMP by the 2nd hour after their insignificant decrease. 1 mcg/ml concentration of EBr increased intracellular cAMP only in 773-cells. The rules changing the cAMP level to isoproterenol and EB2; are determined by differences in reaction of adenylate cyclase, as it has been demonstrated for the 773- and EBr-cells.  相似文献   
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