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51.
Summary The gene FUR4, coding for the uracil permease in Saccharomyces cerevisiae, was mapped on chromosome II, at a distance of 7.8 cM from the centromere on the right arm of the chromosome. In a first step, we used the chromosome loss mapping method developed by Falco and Botstein (1983) to determine on which chromosome the gene mapped. After the observation that FUR4 was closely linked to GAL10, one of the three genes forming the gal cluster (Bassel and Mortimer 1971), we could determine precisely the position of the gene on chromosome II.  相似文献   
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Despite extensive genomic scans, linkage studies of multiplex pedigrees have been unable to produce replicable evidence of genes predisposing to schizophrenia. This indicates that it is unlikely that a single gene accounts for a majority of cases of schizophrenia, even in multiplex pedigrees. It is most likely that schizophrenia is caused by the nonlinear interaction of multiple genetic and environmental factors influencing brain development and function. This conclusion has strong implications for the design of linkage and association studies. Recently designed linkage studies involve several improvements to deal with extensive locus heterogeneity and multiplicative interaction. These improvements include much larger samples of pedigrees, systematic ascertainment and sequential extension rules, and standardized procedures at multiple sites to facilitate collaboration and replication. Future improvements are likely to require advances in the assessment of clinical and neurobiological variability in multiplex pedigrees, more systematic environmental assessment, and advances in analytic methods to deal with multiplicative interaction. Rather than focusing only on schizophrenia as one or more discrete disorders, future linkage efforts should also consider the etiology of individual clinical syndromes or dimensional components of risk that interact to cause the complex pattern of syndromal comorbidity observed within schizophrenics and their families. © 1994 Wiley-Liss, Inc.  相似文献   
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A combined segregation, linkage, and association analysis using the program COMBIN was performed on the simulated pedigree data prepared for the Second Genetic Analysis Workshop. The model used in COMBIN is described and the presented results illustrate its effectiveness in the analysis of such data. Linkage analysis was performed and maps for each linkage group are presented.  相似文献   
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《Vaccine》2021,39(12):1727-1735
BackgroundRisk-based recommendations are common for pneumococcal vaccines but little is known about their uptake. In Australia, pneumococcal conjugate vaccine (PCV) was funded only for Aboriginal or Torres Strait Islander (Indigenous) children and those with underlying medical conditions in 2001, and then there were different booster dose recommendations depending on risk after the introduction of universal PCV vaccination in 2005.MethodsWe measured coverage of PCV dose 3 and additional PCV and 23-valent pneumococcal polysaccharide vaccine (PPV23) doses by risk group among children born in July 2001–December 2012 in two Australian states using linked immunisation and hospitalisation data (available until December 2013). We ascertained medical risk conditions using hospitalisation diagnosis codes and Indigenous status using an established algorithm, comparing coverage for children born pre (2001–2004) and post (2005–2012) universal PCV funding.ResultsAmong 1.3 million children, 63,897 (4.9%) were Indigenous and 32,934 (2.5%) had at least one medically at-risk condition identified by age 6 months. For births in 2001–2004, coverage for PCV dose 3 by 1 year of age was 37% for Indigenous, 15% for medically at-risk and 11% in other children, increasing to 83%, 91% and 92%, respectively for births in 2005–2012. In children with medically at-risk conditions, PCV dose 4 coverage by 2 years was 1% for 2001–2004 births, increasing to 9% for 2005–2012 births, with PPV23 coverage by 6 years 3% in both cohorts. Among eligible Indigenous children, PPV23 coverage by 3 years was 45% for 2001–2004 births and 51% for 2005–2012 births.ConclusionsCoverage with additional recommended booster doses was very low among children with medical conditions, and only modest among Indigenous children. If additional PCV doses are recommended for some risk groups, especially in the context of routine schedules with reduced doses (e.g. 2 + 1 and 1 + 1), measures to improve implementation will be required.  相似文献   
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目的:对我国发布的27份三医联动政策文件的政策工具进行分析,探究我国三医联动政策体系的着重点与缺失点,为健全我国三医联动政策体系提供参考。方法;以我国2014—2019年发布的27份三医联动政策文件为研究对象,以政策工具为视角对纳入分析的政策文件进行摘录和编码,采用内容分析法和定量分析法对各项政策工具进行统计分析,并确定其运用情况。结果:260个政策编号中,需求型,供给型和环境型政策工具分别占6.9%、24.6%和68.5%;医疗、医保和医药政策工具分别占54.2%、24.6%和21.2%。由此可以看出,我国三医联动改革对环境现状的依赖程度较大,需求与供给政策相对不足,而医疗则是三医联动改革的核心关键点。结论:应适当增加需求型和供给型政策工具,着重解决医疗方面的重难点问题,促使医疗、医保、医药三个利益主体达成合力,形成“三医既联又动”的协同发展机制。  相似文献   
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基于统计参数图的脑功能磁共振成像数据处理方法   总被引:1,自引:0,他引:1  
介绍了基于统计参数图的脑功能磁共振成像数据处理方法。脑功能磁共振成像由于其高的时间、空间分辨率、无创性等特点而得到广泛的应用。使用统计参数图进行脑功能成像的数据处理过程主要分为:原始数据的读取、图像预处理、统计分析和统计推论。图像预处理包括运动伪影的消除、图像标准化、图像空间平滑;统计分析包括广义线性模型的建立;统计推论包括T检验等。重点介绍了各个过程所使用的传统的处理方法和最新的处理方法。  相似文献   
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Age of onset heterogeneity in Alzheimer's disease families was modelled by allowing for different liability classes for affected individuals according to their age of onset when calculating lod scores to chromosome 21 and chromosome 19 markers. Linkage to chromosome 21 was supported in the Boston data set, and the method of age correction did not greatly change the lod scores when only affected individuals were analyzed. The location of a gene on chromosome 19 for late age of onset illness was affected by the assumptions about early onset individuals. © 1993 Wiley-Liss, Inc.
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America.
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