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81.
Cancer cells frequently have disease-specific chromosome rearrangements. It is poorly understood why translocations between chromosomes recur at specific breakpoints in the genome. Here we provide evidence that higher-order spatial genome organization is a contributing factor in the formation of recurrent translocations. We show that MYC, BCL and immunoglobulin loci, which are recurrently translocated in various B-cell lymphomas, are preferentially positioned in close spatial proximity relative to each other in normal B cells. Loci in spatial proximity are non-randomly positioned towards the nuclear interior in normal B cells. This locus proximity is the consequence of higher-order genome structure rather than a property of individual genes. Our results suggest that the formation of specific translocations in human lymphomas, and perhaps other tissues, is determined in part by higher-order spatial organization of the genome.  相似文献   
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To identify susceptibility loci for meningioma, we conducted a genome-wide association study of 859 affected individuals (cases) and 704 controls with validation in two independent sample sets totaling 774 cases and 1,764 controls. We identified a new susceptibility locus for meningioma at 10p12.31 (MLLT10, rs11012732, odds ratio = 1.46, P(combined) = 1.88 × 10(-14)). This finding advances our understanding of the genetic basis of meningioma development.  相似文献   
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This paper investigates a reconstruction method for helical computed tomography which compensates for the motion artifacts in the thorax caused by patient breathing.The method takes into account a motion vector field determined from a four-dimensional(4-D) uncompensated image data set.Surface models of the lung and the ribs are tracked through the 4-D data set to create motion information within the entire thorax.Finally,an image is reconstructed using motion compensated back-projection.The results show tha...  相似文献   
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Descartes is always concerned about knowledge. However, the Galileo affair in 1633, the reactions to his Discourse on method, and later his need to reply to objections to his Meditations provoked crises in Descartes’s intellectual development the import of which has not been sufficiently recognized. These events are the major reasons why Descartes’s philosophical position concerning how we know and what we may know is radically different at the end of his life from what it was when he began. We call this later position Descartes’s epistemic stance and contrast it with his earlier methodological, metaphysical realism. Yet Descartes’s epistemic views cannot be separated from other aspects of his work, for example, his views concerning God, causality, metaphysics, and the nature of science. A further meta-implication is that serious errors await any scholar who cites early Cartesian texts in support of late Cartesian positions, or who uses later texts in conjunction with early ones to support a reading of Descartes’s philosophy.  相似文献   
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制造企业从大规模化转向了小型化,其中定单的处理是少量的并且时刻发生变化,这种趋势导致虚拟车间的出现,虚拟车间包括一些分布在车间中的加工中心,阐述了一些基本的概念和方法,用代理关联结构和特征继承关系来解决分布式工艺规划中的特殊问题,在应用中,工艺规划的零件模型的特征继承性是关键,它有助于选择正确的机床和刀具,本文还说明优化工艺规划产生的结果。  相似文献   
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Understanding the role of anthropogenic forcings in regional hydrological changes can help communities plan their adaptation in an informed manner.Here we apply...  相似文献   
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