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71.
72.
Positive assortative mating for age at marriage, birthplace and nationality has been revealed by means of sample analysis of couples married in Moscow in 1955 and 1980. The correlation coefficient between mates for age at marriage was r = 0.81 in 1955 and r = 0.88 in 1980; the age difference between spouses had a mean of 1.55 and 2.21 years, respectively. The determinative role of migration in forming Moscow population marriage structure accounts for the fact that the greater part of marriages registered in the capital are between migrants from various regions of the USSR or between the Moscow-born and the migrants. The proportion of marriages between individuals born in Moscow has increased over 25 years from 10 to 38%, these values being significantly higher than those expected under random mating between the migrants and the Moscow-born. The contingency coefficient measuring the association between the birthplaces of husband and wife was K = 0.16 in 1955 and K = 0.11 in 1980, the preferential marriage between mates born in the same region being still significant even when marriages are registered in Moscow. The highest degrees of assortative mating were observed for nationality character: K = 0.37 in 1955 and K = 0.28 in 1980. The decrease in these values over the past 25 years has resulted in a slight growth of the proportion of international marriages (from 14.75 to 16.53%) which has not yet reached the level expected under panmixia (about 21%). 相似文献
73.
Polypterids, the most basal actinopterygians, are a group of fish long-considered living fossils and holding a key position for understanding fish and tetrapod evolution. Knowledge of the natural history of Polypterus is limited, their having been studied in little detail since the early 1900s. The locomotory habits of wild Polypterus senegalus from Lake Albert, Uganda, were investigated in 2014. High-speed videography demonstrated the capability of large Polypterus to move overland successfully. Contrary to previous evidence, field observations found that terrestrial locomotion in Polypterus is not inherently restricted by body size. Evidence that Polypterus exhibit this behaviour as part of their natural life history can be found in the existence of environmental challenges and the presence of adaptations for amphibious life. 相似文献
74.
Analysis carried out on medical documentation containing data on several thousand healthy and affected babies has revealed patterns of differential mortality and differential morbidity for newborns and infants which allow to estimate relative risk as a function of birth weight and body length. Adaptive norm for anthropometric traits at birth was defined as the weight or length interval in which mortality/morbidity rates were lower than the overall population level. The intensity of stabilizing selection associated with birth weight calculated from these data is several times higher in the neonatal period than for the age interval 1-12 months. Neonatal mortality in more than 50% cases can be attributed to the effects of stabilizing selection associated with birth weight. 相似文献
75.
A method of a quantitative histenzymological analysis was used for determination of the extent of participation of various zones of the adrenal cortex in provision of physiological rhythm of the steroid synthesis. The activity of 3beta-OH-steroid dehydrogenase, glucoso-6-phosphat dehydrogenase, NAD- and NADP-diaphorases, acid and alkaline phosphatases and non-specific esterase was investigated. The data of a histoenzymotological study were compared with the result of biochemical analysis of corticosteroids in the peripheral blood. Under physiological conditions intensification of steroidogenesis was realized by mobilization of individual groups of cells of the adrenal gland, not its whole parenchyma. Physiological rhythm of steroid synthesis was provided by an integrated function of all the zones; however, by duration and quantitative expression of the secretory activity a structural heterogeneity was revealed in the adrenal cortex. 相似文献
76.
Akhmatova NK Semenova IB Donenko FV Kiselevskiĭ MV Kurbatova EA Egorova NB 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2006,(6):35-40
Effect of immunomodulators for microbial origin on innate immunity and antitumor system was continued to study. Immunomodificator Immunovac VP-4, purified staphylococcal toxoid and glucosaminyl muramyl dipeptide (GMDP) equally enhanced cytotoxicity of mononuclear leukocytes of peripheral blood of healthy donors. Index of cytotoxicity was 2.78, 2.77 and 2.70 respectively. Reduced metastatic progression of Lewis lung carcinoma in mice was observed after Immunovac VP-4 and GMDP administration. Effectiveness was seen when preparations administered according to schedules including their administration before implantation of the tumor. If preparations were administered number of metastases reduced in 4.4-5.6 times and size of metastases reduced in 7-10 times. Interplay between antitumor activity of studied immunomodulators and cytotoxic activity of NK-cells, which are base effectors of antitumor immune response, are discussed. 相似文献
77.
78.
Joyce JBC van Beers Annemiek Willemze Jeroen J Jansen Gerard HM Engbers Martin Salden Jos Raats Jan W Drijfhout Annette HM van der Helm-van Mil Rene EM Toes Ger JM Pruijn 《Arthritis research & therapy》2013,15(5):R140
Introduction
Autoantibodies against citrullinated peptides/proteins (ACPA) are found in approximately 75% of the sera of patients with rheumatoid arthritis (RA). The RA-specific ACPA are frequently present prior to disease onset and their presence associates with a more erosive disease course. ACPA can therefore be used to aid the diagnosis and prognosis of RA. Recently, it became clear that ACPA are very heterogeneous, both in an individual patient and among different patients. The aim of this study was to investigate whether clinically meaningful ACPA profiles exist in early RA patients.Methods
Twenty citrullinated peptides and the corresponding non-citrullinated control peptides were immobilized on microarray sensor chips. Sera from 374 early arthritis patients were analyzed by surface plasmon resonance imaging (iSPR) of biomolecular interactions on the sensor chip.Results
Cluster analysis of the reactivities with the citrullinated peptides, after subtraction of the reactivities with the corresponding control peptides confirmed the heterogeneity of the ACPA response in RA and revealed 12 distinct ACPA profiles. The association of the 5 most frequent profiles with clinical features at diagnosis and during the disease course was examined, showing no statistically significant associations.Conclusions
Compared to the detection of ACPA in RA sera by CCP-based assays, ACPA profiling in early arthritis patients did not reveal associations with disease activity and progression scores. 相似文献79.
80.
O. L. Kurbatova E. Yu. Pobedonostseva V. M. Veremeichyk A. S. Prudnikova L. A. Atramentova I. S. Tsybovsky I. G. Udina 《Russian Journal of Genetics》2013,49(4):448-456
Based on data collected from urban residents by questionnaire, the basic parameters of the genetic-demographic structure of populations of the three megalopolises, i.e., Moscow, Kharkov, and Minsk, have been calculated, including the migration coefficients and their dynamics in generations, the radius of the cities migration attraction, the parameters of marriage structure (the proportion of interethnic marriages, the level of intraethnic assortative mating the marital distances), and the gene flow between the ethnic groups. Representatives of the most numerous ethnic group of each megalopolis show significant amount of admixture. For Russians of Moscow, Ukrainians of Kharkov, and Belarusians of Minsk, the proportion of individuals whose ancestors were all born in the given city for at least three generations and belonged to the same nationality turned out to be very low (4.75% in Moscow, 1.83% in Kharkov, and 3.13% in Minsk). This finding questions the formation of a reference population in the megalopolis as a sampling of aboriginals of certain ethnic origins. In the paper, we justify principles of creating genetic databases for the population of the megalopolis taking into account the complexity and dynamism of its population structure. 相似文献