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131.
132.
认识BMP及其受体与口腔正常上皮及其癌变的关系。有助于深入了解口腔上皮癌变的机理。本文用免疫组织化学方法对BMP-2/4,-5与BMPR-IA在口腔颊部粘膜正常上皮,良性病变和癌变中的表达进行观察和半定量分析。标本包括:9例正常上皮(normal buccal muosa,NB)。8例慢性炎症(nonspecific chronic inflammation,NCI),7例过度角化(hyperkeratosis,HK)。5例乳头状瘤(squamous cell papilloma,SCP)。29例鳞癌(squamous cell carcinoma,SCC)。10例癌旁上皮(epithelium immediately adjacent to carcinoma,EAC)以及6例硬腭粘膜上皮(normal mucosa of hard palate,NHP)。结果显示:BMP-2/4,-5与BMPR-IA在口腔粘膜的正常与良性病变上皮中有弱的和不均一的阳性表达,NB与NHP无明显差别,而除3例SCC外,其它SCC几乎均有程度不一的阳性表达,在EAC中的表达接近于SCC,二者明显高于正常与良性组,此外,转移在淋巴结中的癌细胞的BMP-2/4与BMP-5阳性程度略高于原发灶的癌细胞,本文认为;BMP-2/4,5与BMPR-IA可能参与调控口腔上皮的癌变。  相似文献   
133.
As a result of sample cytogenetic studies of 23 persons living on the territory of Yamal-Nentsy Autonomous District and chronically exposed to the small doses of radiation the data on the frequency and spectrum of chromosome aberrations, detected by the routine and differential (GTG) staining were obtained. Comparative efficiency of these methods was determined. The absence of significant differences for the spectrum and frequencies of chromosome aberrations revealed by both methods was shown.  相似文献   
134.
The genetic difference between maize line A188 and A188-derived somaclones was assessed via analysis of randomly amplified polymorphic DNA (RAPD). In total, 15 out of 17 decanucleotide primers used each allowed amplification of 2-17 fragments ranging 200-2000 bp. The RAPD patterns did not differ between individual plants of line A188, which demonstrated again its high genetic homogeneity. The difference between the initial line and the somaclones was high, ranging 64-74%. On evidence of the genetic divergence, the somaclones formed two clusters. The distribution of somaclones between these clusters was consistent with their origin.  相似文献   
135.
RAPD (Random Amplified Polymorphic DNA) and ISSR (Inter Simple Sequence Repeats) markers were used to analyse the genetic divergence between the regenerated plants derived from callus cultures and the original maize line A188. Analysis of polymorphism by using 38 RAPD- and 10 ISSR-oligonucleotide primers showed that the differences between eight examined somaclones and the original line ranged from 6.5 to 23%. As confirmed using new primers, the regenerants derived from callus cultures grouped into two clusters according to their origin. The regenerants isolated from calluses grown for eight months differed from one another and the original line to a larger extent than the regenerants obtained from two-month callus cultures. In some somaclones, molecular marking of the regenerants revealed specific RAPD and ISSR fragments that were absent in other somaclones or the original maize line. On the basis of six specific fragments (five RAPD and one ISSR), SCAR (Sequence Characterized Amplified Region) markers were developed. Specific polymorphism revealed with random primers was completely confirmed using five SCAR markers. Polymorphism of one SCAR marker differed from that revealed with random primers. Five SCAR fragments were inherited as simple dominant traits. One SCAR fragment displayed codominant inheritance.  相似文献   
136.
We examined genetic variation on the nonrecombining portion of the Y chromosome (NRY) to investigate the paternal population structure of indigenous Siberian groups and to reconstruct the historical events leading to the peopling of Siberia. A set of 62 biallelic markers on the NRY were genotyped in 1432 males representing 18 Siberian populations, as well as nine populations from Central and East Asia and one from European Russia. A subset of these markers defines the 18 major NRY haplogroups (A-R) recently described by the Y Chromosome Consortium (YCC 2002). While only four of these 18 major NRY haplogroups accounted for -95% of Siberian Y-chromosome variation, native Siberian populations differed greatly in their haplogroup composition and exhibited the highest phiST value for any region of the world. When we divided our Siberian sample into four geographic regions versus five major linguistic groupings, analyses of molecular variance (AMOVA) indicated higher phiST and phiCT values for linguistic groups than for geographic groups. Mantel tests also supported the existence of NRY genetic patterns that were correlated with language, indicating that language affiliation might be a better predictor of the genetic affinity among Siberians than their present geographic position. The combined results, including those from a nested cladistic analysis, underscored the important role of directed dispersals, range expansions, and long-distance colonizations bound by common ethnic and linguistic affiliation in shaping the genetic landscape of Siberia. The Siberian pattern of reduced haplogroup diversity within populations combined with high levels of differentiation among populations may be a general feature characteristic of indigenous groups that have small effective population sizes and that have been isolated for long periods of time.  相似文献   
137.
Human health status in Russia has declined sharply over the last decade. The massive social changes that have taken place since the fall of the Soviet Union have resulted in increasing morbidity and mortality rates. However, relatively little information is available on the changes in health and disease patterns of Russia's many indigenous populations. The present study examines anthropometric indices of growth status of young children (< 6 years; n = 155), a sensitive index of population health, in three indigenous Evenki communities of Central Siberia between 1991 and 1995. Children of the 1995 sample are significantly shorter, lighter, and leaner than those measured in 1991 and 1992. In 1995, 61 % of Evenki children were growth stunted (heightfor-age z score < -2.0), as compared to 34% in 1991 and 1992 (p < 0.001). Similarly, the prevalence of low weight-for-age (weight-for-age z score < -2.0) children in the 1995 sample was more than double that of the 1991/92 sample (43% vs. 18%; p <0.001), and the prevalence of low weight-for-height (weight-for-height z score < -2.0; "wasting") increased from 2% to 17% (p < 0.001). The levels of growth retardation observed in 1995 are comparable to those seen among impoverished third-world populations. Additionally, the declines in linear growth appear to be particularly pronounced in girls, raising the question of whether there may be differential treatment of boys and girls under these conditions of stress. Overall, these results indicate that increased economic marginalization is having a profound effect on the health and well-being of indigenous Siberian groups. Further work is necessary to determine the proximate causes of the disturbing trends, and the potential solutions and interventions.  相似文献   
138.
Human health risks due to exposure of heavy metals in the atmospheric air of Tomsk, Russia, were studied. The concentrations of 22 metals in the ambient air were calculated on the basis of the ICP–MS experimental determination of their contents in the insoluble fraction of snow cover. Non-carcinogenic hazards were estimated for the areas of power plant (“Zone PP”), brickworks location (“Zone BF”), zone influenced by concrete product plants (“Zone CP”), and petrochemical plant suburbs (“Zone PCP”). Manganese, Al, Cu, and Ba make the largest contribution to the integral non-cancer hazard caused by chronic inhalation intake in all areas. Zinc is added to the above listed elements in the “Zone PP” and V, Co, Cr, and Ni in the “Zone BF” are also added. Densely populated residential areas “Zone BF” and “Zone PP” were characterized by the higher levels of diseases risks associated with human inhalation intake of metals in comparison with other areas. The dust load should be primarily decreased in the zones subjected to harmful effects of brick factories and other construction materials. As to the power station, the portion of natural gas in consumption should increase from year to year for decreasing heavy metal emissions from burning of coal.  相似文献   
139.
Kulikov AV  Osipova DV  Popova NK 《Genetika》2007,43(12):1676-1681
Brain neurotransmitter serotonin is involved in the regulation of many physiological functions and types of behavior. The key enzyme of serotonin synthesis in the brain is tryptophan hydroxylase-2 (TPH-2). An association of the C1473G polymorphism in gene tph2 causing the replacement of Pro447 by Arg447 in TPH-2 molecule with enzyme activity in the mouse brain of 10 inbred strains was found. Association of the polymorphism with the TPH-2 activity in the brain of F2 hybrids between strains C57BL/6 and CC57BR was shown. The results indicate that the C1473G polymorphism in gene tph2 is the main factor determining the genetic defined variability of enzyme activity in the mouse brain.  相似文献   
140.
Molecular Biology - At the International Space Station (ISS), artificial living conditions are created and maintained to satisfy human needs, these conditions are also favorable for the growth of...  相似文献   
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