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991.
992.
Soubhagya R. Nayak Ashwin Krishnamurthy SJ Madhan Kumar Latha V. Prabhu Bhagath Kumar Potu Sujatha D’Costa Anu Vinod Ranade 《Hand (New York, N.Y.)》2010,5(1):31-36
The superficial palmar arch (SPA) and its contributing arteries are highly variable. The palmar type of median artery (PMA)
can be involved in the formation of the SPA by replacing the superficial palmar branch of the radial artery (RA) or the ulnar
artery (UA). The present study was undertaken to investigate the presence of the PMA and its contribution in the formation
of SPA in 42 cadavers (84 upper limbs) of Indian origin. When there was a PMA, its outer diameter was measured in the carpal
tunnel. The PMA was found in 13 upper limbs (15.4%), and of these ten incidences (11.9%), the PMA took part in the formation
of SPA, and in three instances (3.5%), the PMA did not make up part of the SPA. Out of the ten cases in which the PMA contributed
to the formation of SPA, in six cases (7.1%), the PMA anastomosed with the UA; in three cases (3.5%), the PMA anastomosed
with both the UA and the RA, and in one incidence (1.1%), the PMA joined the arteria radialis indicis (deep branch of the
RA) to complete the SPA. The outer diameters of the median arteries varied between 0.8 and 2.6 mm with the mean value of 1.7 mm.
The present study concludes that the median–ulnar type of SPA was the most common type of SPA when the PMA was encountered
as a source of superficial arterial arcade of the hand, followed by the radial–median–ulnar type. The vascular patterns found
in this study are important to hand surgeons. The present study of PMA origin, course, and its contribution to the SPA will
add to the existing knowledge of the vascular anatomy of forearm and hand. 相似文献
993.
Katarzyna Bryc Adam Auton Matthew R. Nelson Jorge R. Oksenberg Stephen L. Hauser Scott Williams Alain Froment Jean-Marie Bodo Charles Wambebe Sarah A. Tishkoff Carlos D. Bustamante 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(2):786-791
Quantifying patterns of population structure in Africans and African Americans illuminates the history of human populations and is critical for undertaking medical genomic studies on a global scale. To obtain a fine-scale genome-wide perspective of ancestry, we analyze Affymetrix GeneChip 500K genotype data from African Americans (n = 365) and individuals with ancestry from West Africa (n = 203 from 12 populations) and Europe (n = 400 from 42 countries). We find that population structure within the West African sample reflects primarily language and secondarily geographical distance, echoing the Bantu expansion. Among African Americans, analysis of genomic admixture by a principal component-based approach indicates that the median proportion of European ancestry is 18.5% (25th–75th percentiles: 11.6–27.7%), with very large variation among individuals. In the African-American sample as a whole, few autosomal regions showed exceptionally high or low mean African ancestry, but the X chromosome showed elevated levels of African ancestry, consistent with a sex-biased pattern of gene flow with an excess of European male and African female ancestry. We also find that genomic profiles of individual African Americans afford personalized ancestry reconstructions differentiating ancient vs. recent European and African ancestry. Finally, patterns of genetic similarity among inferred African segments of African-American genomes and genomes of contemporary African populations included in this study suggest African ancestry is most similar to non-Bantu Niger-Kordofanian-speaking populations, consistent with historical documents of the African Diaspora and trans-Atlantic slave trade. 相似文献
994.
已婚流动人口避孕节育服务利用情况分析 总被引:1,自引:0,他引:1
目的:了解近年来流动人口避孕节育服务利用情况及变化趋势,以期为提升流动人口避孕节育服务质量提供依据。方法:从2013年全国流动人口动态监测数据中选取年龄在16~49岁且首次外出时间在2007年以前、现用避孕方法始于2008年1月~2013年5月的已婚女性共17429人,分析其避孕节育措施利用状况及相关影响因素。结果:宫内节育器、避孕套、绝育术是该人群最主要的3种避孕措施,从2008年~2012年,在流入地获得服务的比例从49.24%上升到了69.21%,选择避孕套避孕的比例从37.14%上升到了52.11%。多因素logistic分析显示,现居住在城镇、非农业户口、低年龄、文化程度较高、亲生子女数量少、未持婚育证明和未报告避孕节育状况、跨省流动的已婚育龄妇女更可能选择避孕套避孕。结论:越来越多的流动人口在流入地获得避孕节育服务,避孕套成为流动人口首选方式;应提升流入地避孕节育手术服务的可及性,并加强生殖健康宣传教育,促进避孕套的正确使用。 相似文献
995.
《Clinical and experimental hypertension (New York, N.Y. : 1993)》2013,35(4):897-903
It is a paradox that intra-population studies fail to show significant correlation between sodium excretion and blood pressure while a clear relationship exists in cross-cultural studies. Since daily variation of sodium excretion is high, the discrepancy between the two observations could be due to non -comparable data on sodium excretion. This is a discussion of the hypothesis that the finding of a significant correlation or not between sodium excretion and blood pressure depends on the statistical analysis of the data. 相似文献
996.
Magnesium is unique among biological cations. Its volume change from hydrated cation to atomic ion is over an order of magnitude larger than that of any other biological cation. This volume change presents particular problems for a magnesium transport system and suggests that these systems may be significantly different from other classes of ion transport systems. Detailed study of Mg2+ transport in complex organisms is limited by severe technical problems. However, molecular genetic techniques have enabled the isolation of three Mg2+ transport systems from the Gram-negative bacterium Salmonella typhimurium. The MgtA and MgtB transport systems are members of the P-type ATPase superfamily of transporters but possess unique characteristics among members of this family. The CorA transport protein is the first member of an entirely new class of transport proteins. In addition, another completely new family of Mg2+ transport proteins have been identified that is present in both Gram-negative and Gram-positive bacteria. Characterization of these transporters should provide substantial insight into Mg2+ transport and cellular Mg2+ homeostasis. 相似文献
997.
Katie Dreiling Stacey Trushenski Diane Kayongo-Male Bonny Specker 《Public health nursing (Boston, Mass.)》2009,26(2):192-201
ABSTRACT The National Children's Study (NCS) is a longitudinal study that will examine the influence of environmental and social factors on the health and development of 100,000 children, following them from before birth until age 21. Proposed participant recruitment methods call for locating and listing all dwelling units (DUs) located within randomly selected segments within the 105 NCS sites. One of seven Vanguard Centers of the NCS includes four rural counties that span approximately 2,500 square miles. The size of this sampling area presents unique geographic challenges. In order to determine the most efficient method for listing DUs within this large area, a study was undertaken to investigate the differences in the percent of DUs identified and the cost of four different approaches. It compared the on-site listing method of physically identifying each DU with three other methods: plat maps, postal listings, and Geographic Information Systems (GIS)/satellite imagery techniques. The on-site method had the strongest κ (.85) in terms of identifying true DUs. There was a moderate agreement (.59) with the plat map method, fair agreement (.34) with the postal method, and only a slight agreement (.14) with the GIS/satellite imagery method. The plat map, postal listing, and GIS/satellite methods were less time-consuming than the on-site method. 相似文献
998.
Infodemiology can be defined as the science of distribution and determinants of information in an electronic medium, specifically the Internet, or in a population, with the ultimate aim to inform public health and public policy. Infodemiology data can be collected and analyzed in near real time. Examples for infodemiology applications include: the analysis of queries from Internet search engines to predict disease outbreaks (eg. influenza); monitoring peoples'' status updates on microblogs such as Twitter for syndromic surveillance; detecting and quantifying disparities in health information availability; identifying and monitoring of public health relevant publications on the Internet (eg. anti-vaccination sites, but also news articles or expert-curated outbreak reports); automated tools to measure information diffusion and knowledge translation, and tracking the effectiveness of health marketing campaigns. Moreover, analyzing how people search and navigate the Internet for health-related information, as well as how they communicate and share this information, can provide valuable insights into health-related behavior of populations. Seven years after the infodemiology concept was first introduced, this paper revisits the emerging fields of infodemiology and infoveillance and proposes an expanded framework, introducing some basic metrics such as information prevalence, concept occurrence ratios, and information incidence. The framework distinguishes supply-based applications (analyzing what is being published on the Internet, eg. on Web sites, newsgroups, blogs, microblogs and social media) from demand-based methods (search and navigation behavior), and further distinguishes passive from active infoveillance methods. Infodemiology metrics follow population health relevant events or predict them. Thus, these metrics and methods are potentially useful for public health practice and research, and should be further developed and standardized. 相似文献
999.
EK Greisenegger N Novak L Maintz T Bieber F Zimprich D Haubenberger A Gleiss G Stingl T Kopp A Zimprich 《Journal of the European Academy of Dermatology and Venereology》2010,24(5):607-610
Background Recently, mutations in the filaggrin gene (FLG) have been shown to be a major predisposing factor for atopic dermatitis (AD). Objective In this study, we evaluated the influence of four prevalent mutations (R501X, 2282del4, R2447X and S3247X) in a large cohort of 462 Austrian and German AD patients and in 402 control individuals. Results We found a strong association of the FLG mutations with AD. Subgroup analysis revealed a significantly higher proportion of patients with an early age of disease onset and significantly higher median serum IgE levels among mutation carriers. Furthermore, we observed an overrepresentation of null alleles in AD patients with concomitant asthma compared with those without this co‐morbidity. Conclusion Our data confirm and extend the knowledge of the influence of FLG mutations in AD. 相似文献
1000.
K. V. Arunkumar Viveka Vardhan Reddy David P. Tauro 《Journal of maxillofacial and oral surgery》2010,9(2):127-133