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Nei's coefficient of genetic differentiation (Gst) was used to estimate the intergroup differentiation of four ethnic geographic groups of Bashkirs and the interethnic differentiation of seven ethnoses (Bashkirs, Tatars, Chuvashes, Udmurts, Maris, Komis, and Mordovians) from the Volga-Ural region. The coefficient of genetic differentiation calculated from data on four polymorphic loci (MET, D7S23, PKU, and apoB) and classical biochemical markers (AB0, MN, Rh, Hp, and AcP) of the nuclear genome was similar in all tested populations. The genetic difference between the ethnoses from the Volga-Ural region (Gst = 1.91%) was intermediate between that in European (Gst = 1.18%) and Siberian (Gst = 5.84%) ethnoses.  相似文献   
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Addition of Polyethylene glycol(PEG) to the nutrient medium of wheatseedlings led to a rapid cessation of leaf growth and shrinkage, measured withahighly sensitive growth sensor, followed by a partial restoration of extensionin the subsequent 40 min. This osmotic shock resulted in IAAaccumulation in the shoots. Leaf extensibility, measured by addition of 5g as a counterweight to an extensiometer, did not change for 20min after the start of the treatment, but then increased andbecametwice as high as the initial value. Changes in leaf extensibility coincidedwitha restoration of leaf growth. Leaf shrinkage, which was observed immediatelyafter addition of the osmoticum, suggests that the initial growth response wasdue to a water deficit, which led to a decrease in cell turgor. Howeverrestoration of growth during water stress could be due to changes in cell wallrheological properties, which could be triggered by IAA accumulation.  相似文献   
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Hypermethylation is an important mechanism for the dynamic regulation of gene expression, necessary for metastasizing tumour cells. Our aim is to identify methylation tumour markers that have a predictive value for the presence of regional lymph node metastases in patients with oral and oropharyngeal squamous cell carcinoma (OOSCC). Significantly differentially expressed genes were retrieved from four reported microarray expression profiles comparing pN0 and pN+ head-neck tumours, and one expression array identifying functionally hypermethylated genes. Additional metastasis-associated genes were included from the literature. Thus genes were selected that influence the development of nodal metastases and might be regulated by methylation. Methylation-specific PCR (MSP) primers were designed and tested on 8 head-neck squamous cell carcinoma cell lines and technically validated on 10 formalin-fixed paraffin-embedded (FFPE) OOSCC cases. Predictive value was assessed in a clinical series of 70 FFPE OOSCC with pathologically determined nodal status. Five out of 28 methylation markers (OCLN, CDKN2A, MGMT, MLH1 and DAPK1) were frequently differentially methylated in OOSCC. Of these, MGMT methylation was associated with pN0 status (P = 0.02) and with lower immunoexpression (P = 0.02). DAPK1 methylation was associated with pN+ status (P = 0.008) but did not associate with protein expression. In conclusion, out of 28 candidate genes, two (7%) showed a predictive value for the pN status. Both genes, DAPK1 and MGMT, have predictive value for nodal metastasis in a clinical group of OOSCC. Therefore DNA methylation markers are capable of contributing to diagnosis and treatment selection in OOSCC. To efficiently identify additional new methylation markers, genome-wide methods are needed.  相似文献   
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Chemokine CCL2, or monocytic chemoatractant protein 1 (CCL2/MCP-1) plays an important role in the development of cardiovascular diseases. In the present study, genotypes of four polymorphic markers (rs1860190, rs1024611, rs3917887, and rs991804) of the CCL2gene were identified in the population of Tatars (residents of the Republic of Bashkortostan). Analysis of associations of these markers with essential hypertension (EH) was carried out. It was demonstrated that haplotype CCL2*A*G*D*T was associated with the increased risk of EH (P = 0.01; OR = 1.53).  相似文献   
87.
A mutation of wing fragility that was not yet been revealed in adult housefly is described. Criss-cross inheritance of the character of fragility of the wing blade, which indicates localization of gene (fw) for this character in the X chromosome. Phenotypic expression of the mutant allele depends on sex. In male flies, the mutant allele in hemizygous state is expressed at the age of 2-3 weeks and older with penetrance close to 100%. In females, the mutant allele in homozygous state is lethal and in heterozygous state, totally recessive.  相似文献   
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Russian Journal of Genetics - The aim of this study was to investigate the associations between the polymorphic loci in the JAK/STAT signaling pathway and the aging processes and longevity in the...  相似文献   
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