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111.
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   
112.
De novo somatic mutations in focal areas are well documented in diseases such as neoplasia but are rarely reported in malformation of the developing brain. Hemimegalencephaly (HME) is characterized by overgrowth of either one of the two cerebral hemispheres. The molecular etiology of HME remains a mystery. The intractable epilepsy that is associated with HME can be relieved by the surgical treatment hemispherectomy, allowing sampling of diseased tissue. Exome sequencing and mass spectrometry analysis in paired brain-blood samples from individuals with HME (n = 20 cases) identified de novo somatic mutations in 30% of affected individuals in the PIK3CA, AKT3 and MTOR genes. A recurrent PIK3CA c.1633G>A mutation was found in four separate cases. Identified mutations were present in 8-40% of sequenced alleles in various brain regions and were associated with increased neuronal S6 protein phosphorylation in the brains of affected individuals, indicating aberrant activation of mammalian target of rapamycin (mTOR) signaling. Thus HME is probably a genetically mosaic disease caused by gain of function in phosphatidylinositol 3-kinase (PI3K)-AKT3-mTOR signaling.  相似文献   
113.
Although the Copernican hypothesis is popularized in Japan by Shiba Kōkan's books published between 1793 and 1805, the whole of the conceptions of the Occidental astronomy remains unknown at that time to most of the Japanese. Through the publication of Ensei kanshō zusetsu in 1823, Yoshio Nankō does achieve posthumously the project designed two years earlier by his young disciple, Kusano Yōjun, to spread this knowledge widely among the society. The book is a great and unprecedented success. Well known nowadays for its appendix (Chidō wakumon) and the influence that its content, while claiming the mobility of the Earth, did exert on the propagation of the heliocentrism in Japan until the very end of the Edo period, the book also provides as we think an unexpected and completely new platform for classical science, being the emissary of certain concepts invented by Shizuki Tadao from his relentless studies of Newtonian mechanics. Once we briefly recount Yoshio's career and discuss the sources and the morphology of his work, we give some arguments towards it.  相似文献   
114.
Bronchial asthma is a common inflammatory disease caused by the interaction of genetic and environmental factors. Through a genome-wide association study and a replication study consisting of a total of 7,171 individuals with adult asthma (cases) and 27,912 controls in the Japanese population, we identified five loci associated with susceptibility to adult asthma. In addition to the major histocompatibility complex and TSLP-WDR36 loci previously reported, we identified three additional loci: a USP38-GAB1 locus on chromosome 4q31 (combined P = 1.87 × 10(-12)), a locus on chromosome 10p14 (P = 1.79 × 10(-15)) and a gene-rich region on chromosome 12q13 (P = 2.33 × 10(-13)). We observed the most significant association with adult asthma at rs404860 in the major histocompatiblity complex region (P = 4.07 × 10(-23)), which is close to rs2070600, a SNP previously reported for association with FEV(1)/FVC in genome-wide association studies for lung function. Our findings offer a better understanding of the genetic contribution to asthma susceptibility.  相似文献   
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116.
Recently, two common sequence variants on 9p21, tagged by rs10757278-G and rs10811661-T, were reported to be associated with coronary artery disease (CAD) and type 2 diabetes (T2D), respectively. We proceeded to further investigate the contributions of these variants to arterial diseases and T2D. Here we report that rs10757278-G is associated with, in addition to CAD, abdominal aortic aneurysm (AAA; odds ratio (OR) = 1.31, P = 1.2 x 10(-12)) and intracranial aneurysm (OR = 1.29, P = 2.5 x 10(-6)), but not with T2D. This variant is the first to be described that affects the risk of AAA and intracranial aneurysm in many populations. The association of rs10811661-T to T2D replicates in our samples, but the variant does not associate with any of the five arterial diseases examined. These findings extend our insight into the role of the sequence variant tagged by rs10757278-G and show that it is not confined to atherosclerotic diseases.  相似文献   
117.
In this paper various molecular chemical interactions are modelled under different computational paradigms. P systems andπ-calculus are used to describe intra-cellular reactions like protein-protein interactions and gene regulation control.  相似文献   
118.
Mechanisms of long-distance dispersal of seeds by wind   总被引:35,自引:0,他引:35  
Nathan R  Katul GG  Horn HS  Thomas SM  Oren R  Avissar R  Pacala SW  Levin SA 《Nature》2002,418(6896):409-413
  相似文献   
119.
Summary This report completes the examination of the 3 butadiynes substituted with phenyl and thienyl groups, and their related thiophene molecules. With the exception of 2,5-diphenylthiophene, they are all non-photodynamic (type B) phototoxic compounds.Acknowledgments. We are grateful to the National Institutes of Health for the support of this research (GM 24144).  相似文献   
120.
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