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We examined the multifarious genetic heterogeneity of Europe and neighboring regions from a geographical perspective. We created composite maps outlining the estimated geographical distribution of major groups of genetically similar individuals on the basis of forensic Y-chromosomal markers. We analyzed Y-chromosomal haplotypes composed of 7 highly polymorphic STR loci, genotyped for 33,010 samples, collected at 249 sites in Europe, Western Asia and North Africa, deposited in the YHRD database (www.yhrd.org). The data set comprised 4176 different haplotypes, which we grouped into 20 clusters. For each cluster, the frequency per site was calculated. All geostatistical analysis was performed with the geographic information system GRASS-GIS. We interpolated frequency values across the study area separately for each cluster. Juxtaposing all 20 interpolated surfaces, we point-wisely screened for the highest cluster frequencies and stored it in parallel with the respective cluster label. We combined these two types of data in a composite map. We repeated this procedure for the second highest frequencies in Europe. Major groups were assigned to Northern, Western and Eastern Europe. North Africa built a separate region, Southeastern Europe, Turkey and Near East were divided into several regions. The spatial distribution of the groups accounting for the second highest frequencies in Europe overlapped with the territories of the largest countries. The genetic structure presented in the composite maps fits major historical geopolitical regions and is in agreement with previous studies of genetic frequencies, validating our approach. Our genetic geostatistical approach provides, on the basis of two composite maps, detailed evidence of the geographical distribution and relative frequencies of the most predominant groups of the extant male European population, examined on the basis of forensic Y-STR haplotypes. The existence of considerable genetic differences among geographic subgroups in Europe has important consequences for the statistical inference in forensic Y-STR haplotype analyses.  相似文献   
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Sleep and Breathing - We prospectively investigated the effects of continuous positive airway pressure (CPAP) on long-term cognitive and psychomotor performances, and excessive daytime sleepiness...  相似文献   
997.
Alexander Brunschwig was very important person in surgical oncology during the 20th century. He helped Maximow and Bloom to write their well-known histology text "A text-book of histology", he was the first to do a one-stage radical pancreatoduodenectomy and pelvic exenteration. Doctor Alexander Brunschwig was born in El Paso, Texas, on September 11, 1901. He graduated from Rush Medical College in 1927. He was named for the chief of gynecology and clinical assistant at Clinics and Medical School of the Chicago University in 1933. He became professor of surgery at the same University in 1940 where he worked until 1947. Doctor Brunschwig moved to New York in 1947 and became the Chief of gynecology in Memorial Hospital for Cancer and Allied Diseases and professor of clinical surgery at Cornell University at Medical College. He published some very important books about oncology, "The Surgery of Pancreatic Tumors", "Radical Surgery in Advanced Abdominal Cancer" and "L' Exenteration pelvienne".  相似文献   
998.
The most frequent benign gallbladder polyps are cholesterol polyps. Next in frequency were adenomas, which may have malignant potential. The aim of this study was to assess the possibility of ultrasonography in the diagnosis and differential diagnosis of cholesterol polyps compared to adenomas. Patients were examined during the period from October 2006. to December 2008. In Department of Ultrasound, Clinic for Gastroenterology and Hepatology, Belgrade. The group of 54 patients analyzed consisted of 30 women (56%) and 24 men (44%). Most (59%) had solitary polyps. In 92.6% of patients the size of polyps was below 10 mm. 74% of respondents were over 50 years. Ultrasonography is the method of choice and gold standard in diagnosis of gallbladder polyps. Based on echoic properties cholesterol polyps can not be distinguished from adenomas. Malignant alteration of polyps also could not be detected. Appropriate ultrasonographic characteristics such as size of polyps, appearance of a broad base that sits on the wall, concomitant lithiasis findings and patient age may be indicative for malignancy.  相似文献   
999.
von Willebrand factor (VWF) is an essential component of hemostasis and has been implicated in thrombosis. Multimer size and the amount of circulating VWF are known to impact hemostatic function. We associated 78 VWF single nucleotide polymorphisms (SNPs) and haplotypes constructed from those SNPs with VWF antigen level in 7856 subjects of European descent. Among the nongenomic factors, age and body mass index contributed 4.8% and 1.6% of VWF variation, respectively. The SNP rs514659 (tags O blood type) contributed 15.4% of the variance. Among the VWF SNPs, we identified 18 SNPs that are associated with levels of VWF. The correlative SNPs are either intronic (89%) or silent exonic (11%). Although SNPs examined are distributed throughout the entire VWF gene without apparent cluster, all the positive SNPs are located in a 50-kb region. Exons in this region encode for VWF D2, D', and D3 domains that are known to regulate VWF multimerization and storage. Mutations in the D3 domain are also associated with von Willebrand disease. Fifteen of these 18 correlative SNPs are in 2 distinct haplotype blocks. In summary, we identified a cluster of intronic VWF SNPs that associate with plasma levels of VWF, individually or additively, in a large cohort of healthy subjects.  相似文献   
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