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41.
导读:自从微软购买SCO公司的Unix技术使用许可之后,Windows和Linux两种操作系统之间的争夺似乎有愈演愈烈之势。到底二者之间孰优孰劣,哪种更容易出现安全问题呢?《NewsFactor》网站就此撰写了一份特别报道,从各方业内分析师的角度帮助对两种操作系统的表现进行了对比和分析。  相似文献   
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The incidence of melanoma is increasing more than any other cancer, and knowledge of its genetic alterations is limited. To systematically analyze such alterations, we performed whole-exome sequencing of 14 matched normal and metastatic tumor DNAs. Using stringent criteria, we identified 68 genes that appeared to be somatically mutated at elevated frequency, many of which are not known to be genetically altered in tumors. Most importantly, we discovered that TRRAP harbored a recurrent mutation that clustered in one position (p. Ser722Phe) in 6 out of 167 affected individuals (~4%), as well as a previously unidentified gene, GRIN2A, which was mutated in 33% of melanoma samples. The nature, pattern and functional evaluation of the TRRAP recurrent mutation suggest that TRRAP functions as an oncogene. Our study provides, to our knowledge, the most comprehensive map of genetic alterations in melanoma to date and suggests that the glutamate signaling pathway is involved in this disease.  相似文献   
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Although murine X-linked muscular dystrophy (mdx) and Duchenne muscular dystrophy (DMD) are genetically homologous and both characterized by a complete absence of dystrophin, the limb muscles of adult mdx mice suffer neither the detectable weakness nor the progressive degeneration that are features of DMD. Here we show that the mdx mouse diaphragm exhibits a pattern of degeneration, fibrosis and severe functional deficit comparable to that of DMD limb muscle, although adult mice show no overt respiratory impairment. Progressive functional changes include reductions in strength (to 13.5% of control by two years of age), elasticity, twitch speed and fibre length. The collagen density rises to at least seven times that of control diaphragm and ten times that of mdx hind-limb muscle. By 1.5 years of age, similar but less severe histological changes emerge in the accessory muscles of respiration. On the basis of these findings, we propose that dystrophin deficiency alters the threshold for work-induced injury. Our data provide a quantitative framework for studying the pathogenesis of dystrophy and extend the application of the mdx mouse as an animal model.  相似文献   
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The double puzzle of diabetes   总被引:12,自引:0,他引:12  
Diamond J 《Nature》2003,423(6940):599-602
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Evolution,consequences and future of plant and animal domestication   总被引:36,自引:0,他引:36  
Diamond J 《Nature》2002,418(6898):700-707
Domestication interests us as the most momentous change in Holocene human history. Why did it operate on so few wild species, in so few geographic areas? Why did people adopt it at all, why did they adopt it when they did, and how did it spread? The answers to these questions determined the remaking of the modern world, as farmers spread at the expense of hunter-gatherers and of other farmers.  相似文献   
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F Michal  M H Maguire  G Gough 《Nature》1969,222(5198):1073-1074
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M H Maguire  F Michal 《Nature》1968,217(5128):571-573
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