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O’Beirne Sarah L. Chazen J. Levi Cornman-Homonoff Joshua Carey Bridget T. Gelbman Brian D. 《Lung》2019,197(6):727-733
Lung - Diaphragmatic paralysis (DP) is an important cause of dyspnea with many underlying etiologies; however, frequently no cause is identified despite extensive investigation. We hypothesized... 相似文献
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Bridget A. Bagert 《Current neurology and neuroscience reports》2009,9(5):405-410
Recent seroepidemiologic and pathologic evidence suggests that prior infection with Epstein-Barr virus (EBV) may be necessary
for the development of multiple sclerosis (MS). EBV infects more than 90% of all humans, most of whom remain healthy. In contrast,
99% of MS patients have evidence of prior infection with EBV. EBV infects resting B lymphocytes, immortalizing them into long-lived
memory B cells that survive largely undetected by the immune system in the peripheral circulation. MS patients show elevated
titers to EBV years before developing any neurologic symptoms. Postmortem pathologic analysis of brains of patients with MS
has revealed diffuse EBV-associated B-cell dysregulation in all forms of MS. Theories of pathogenesis of EBV in MS include
antigenic mimicry, immortalization of B-cell clones, and cytotoxic T-cell dysfunction against virally infected B cells. This
article reviews the existing evidence of the relationship between EBV and MS and considers the therapeutic implication of
this evidence. 相似文献
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Optimal Selection of Sib Pairs from Random Samples for Linkage Analysis of a QTL Using the EDAC Test
Percentages of extremely concordant and extremely discordant sib pairs are calculated that maximize the power to detect a quantitative trait locus (QTL) under a variety of circumstances using the EDAC test. We assume a large fixed number of randomly sampled sib pairs, such as one would hope to find in the large twin registries, and limited resources to genotype a certain number of selected sib pairs. Our aim is to investigate whether optimal selection can be achieved when prior knowledge concerning the QTL gene action, QTL allele frequency, QTL effect size, and background (residual) sib correlation is limited or absent. To this end we calculate the best selection percentages for a large number of models, which differ in QTL gene action allele frequency, background correlation, and QTL effect size. By averaging these percentages over gene action, over allele frequency, over gene action, and over allele frequencies, we arrive at general recommendations concerning selection percentages. The soundness of these recommendations is subsequently in a number of test cases. 相似文献
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