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At present the scope of research in radio astronomy is limited by the allocation of frequencies, some of which have to be shared with other radio services. When the International Telecommunications Union reconsiders all frequency allocations next year, astronomers are hoping for an improvement. 相似文献
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Natural selection and the concept of a protein space 总被引:16,自引:0,他引:16
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D. F. Smith 《Cellular and molecular life sciences : CMLS》1976,32(10):1320-1321
Summary Injection of hypertonic LiCl i.p. has several nonspecific adverse effects in rats. No evidence was obtained forJohnson's hypothesis that the effect of LiCl on rearing is mediated by environmental stimuli.Acknowledgments. The author thanks Aarhus University, The Danish Medical Research Council, andMarianne Jensen for assistance. 相似文献
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Sporadic autism exomes reveal a highly interconnected protein network of de novo mutations 总被引:2,自引:0,他引:2
O'Roak BJ Vives L Girirajan S Karakoc E Krumm N Coe BP Levy R Ko A Lee C Smith JD Turner EH Stanaway IB Vernot B Malig M Baker C Reilly B Akey JM Borenstein E Rieder MJ Nickerson DA Bernier R Shendure J Eichler EE 《Nature》2012,485(7397):246-250
It is well established that autism spectrum disorders (ASD) have a strong genetic component; however, for at least 70% of cases, the underlying genetic cause is unknown. Under the hypothesis that de novo mutations underlie a substantial fraction of the risk for developing ASD in families with no previous history of ASD or related phenotypes--so-called sporadic or simplex families--we sequenced all coding regions of the genome (the exome) for parent-child trios exhibiting sporadic ASD, including 189 new trios and 20 that were previously reported. Additionally, we also sequenced the exomes of 50 unaffected siblings corresponding to these new (n = 31) and previously reported trios (n = 19), for a total of 677 individual exomes from 209 families. Here we show that de novo point mutations are overwhelmingly paternal in origin (4:1 bias) and positively correlated with paternal age, consistent with the modest increased risk for children of older fathers to develop ASD. Moreover, 39% (49 of 126) of the most severe or disruptive de novo mutations map to a highly interconnected β-catenin/chromatin remodelling protein network ranked significantly for autism candidate genes. In proband exomes, recurrent protein-altering mutations were observed in two genes: CHD8 and NTNG1. Mutation screening of six candidate genes in 1,703 ASD probands identified additional de novo, protein-altering mutations in GRIN2B, LAMC3 and SCN1A. Combined with copy number variant (CNV) data, these results indicate extreme locus heterogeneity but also provide a target for future discovery, diagnostics and therapeutics. 相似文献
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