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Systematic efforts are underway to decipher the genetic changes associated with tumor initiation and progression. However, widespread clinical application of this information is hampered by an inability to identify critical genetic events across the spectrum of human tumors with adequate sensitivity and scalability. Here, we have adapted high-throughput genotyping to query 238 known oncogene mutations across 1,000 human tumor samples. This approach established robust mutation distributions spanning 17 cancer types. Of 17 oncogenes analyzed, we found 14 to be mutated at least once, and 298 (30%) samples carried at least one mutation. Moreover, we identified previously unrecognized oncogene mutations in several tumor types and observed an unexpectedly high number of co-occurring mutations. These results offer a new dimension in tumor genetics, where mutations involving multiple cancer genes may be interrogated simultaneously and in 'real time' to guide cancer classification and rational therapeutic intervention.  相似文献   
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Schizophrenia is a severe psychiatric disorder that profoundly affects cognitive, behavioral and emotional processes. The wide spectrum of symptoms and clinical variability in schizophrenia suggest a complex genetic etiology, which is consistent with the numerous loci thus far identified by linkage, copy number variation and association studies. Although schizophrenia heritability may be as high as ~80%, the genes responsible for much of this heritability remain to be identified. Here we sequenced the exomes of 14 schizophrenia probands and their parents. We identified 15 de novo mutations (DNMs) in eight probands, which is significantly more than expected considering the previously reported DNM rate. In addition, 4 of the 15 identified DNMs are nonsense mutations, which is more than what is expected by chance. Our study supports the notion that DNMs may account for some of the heritability reported for schizophrenia while providing a list of genes possibly involved in disease pathogenesis.  相似文献   
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B Pessac  A Girard  G Romey  P Crisanti  A M Lorinet  G Calothy 《Nature》1983,302(5909):616-618
Neuroretina (NR) is an evagination of the central nervous system (CNS) which is composed of photoreceptors, glial (Müller) cells and horizontal, bipolar, amacrine and ganglion neuronal cells. We describe here the usefulness of Rous sarcoma virus (RSV) in the establishment of a neuronal clone from quail embryo neuroretina. When primary cultures of chick and quail embryo neuroretina cells are transformed by RSV, neuronal markers such as ribbon synapses, choline acetyltransferase (CAT) and glutamic acid decarboxylase (GAD) specific activity are present. These RSV-transformed primary cultures can be established into permanent cell lines from which neuronal clones have been isolated. One of them, clone QNR/D, can generate tetrodotoxin(TTX)-inhibitable action potentials on electrical stimulation, has a high GAD activity and binds monoclonal antibodies raised against chick embryo neuroretina. The presence of these neuronal markers suggests that the QNR/D clone is derived from cells of the amacrine or ganglionic lineage. This is the first time that a neuronal cell clone of defined origin has been obtained from the CNS. The neuronal markers of the QNR/D clone are expressed at both the permissive and the non-permissive temperatures for transformation.  相似文献   
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基于8根混凝土倒T形叠合梁受弯试验,研究了钢筋钢纤维自应力混凝土做加固材料层二次浇注到待加固混凝土T形梁,从而形成的叠合梁在负弯矩区的抗裂性能.试验结果表明,仅占叠合梁高13.9%的叠合层将梁的开裂弯矩提高44.9%.同时根据已有理论模型,推导了自应力混凝土叠合T梁后加自应力的求法和负弯矩区正截面抗裂计算公式,其计算结果与试验结果比较吻合.  相似文献   
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