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51.
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Siridechadilok B Fraser CS Hall RJ Doudna JA Nogales E 《Science (New York, N.Y.)》2005,310(5753):1513-1515
Protein synthesis in mammalian cells requires initiation factor eIF3, a approximately 750-kilodalton complex that controls assembly of 40S ribosomal subunits on messenger RNAs (mRNAs) bearing either a 5'-cap or an internal ribosome entry site (IRES). Cryo-electron microscopy reconstructions show that eIF3, a five-lobed particle, interacts with the hepatitis C virus (HCV) IRES RNA and the 5'-cap binding complex eIF4F via the same domain. Detailed modeling of eIF3 and eIF4F onto the 40S ribosomal subunit reveals that eIF3 uses eIF4F or the HCV IRES in structurally similar ways to position the mRNA strand near the exit site of 40S, promoting initiation complex assembly. 相似文献
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Prinn R Cunnold D Rasmussen R Simmonds P Alyea F Crawford A Fraser P Rosen R 《Science (New York, N.Y.)》1987,238(4829):945-950
Frequent atmospheric measurements of the anthropogenic compound methylchloroform that were made between 1978 and 1985 indicate that this species is continuing to increase significantly around the world. Reaction with the major atmospheric oxidant, the hydroxyl radical (OH), is the principal sink for this species. The observed mean trends for methylchloroform are 4.8, 5.4, 6.4, and 6.9 percent per year at Aldrigole (Ireland) and Cape Meares (Oregon), Ragged Point (Barbados), Point Matatula (American Samoa), and Cape Grim (Tasmania), respectively, from July 1978 to June 1985. These measured trends, combined with knowledge of industrial emissions, were used in an optimal estimation inversion scheme to deduce a globally averaged methylchloroform atmospheric lifetime of 6.3 (+ 1.2, -0.9) years (1sigma uncertainty) and a globally averaged tropospheric hydroxyl radical concentration of (7.7 +/- 1.4) x 10(5) radicals per cubic centimeter (1sigma uncertainty). These 7 years of gas chromatographic measurements, which comprise about 60,000 individual calibrated real-time air analyses, provide the most accurate estimates yet of the trends and lifetime of methylchloroform and of the global average for tropospheric hydroxyl radical levels. Accurate determination of hydroxyl radical levels is crucial to understanding global atmospheric chemical cycles and trends in the levels of trace gases such as methane. 相似文献
55.
Eigner J Watson JD Haselkorn R Signer E Fraser D Echols H 《Science (New York, N.Y.)》1968,162(3853):511
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Ainley DG Ballard G Emslie SD Fraser WR Wilson PR Woehler EJ 《Science (New York, N.Y.)》2003,300(5618):429-30; author reply 429-30
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Much has been gained from genomic and evolutionary studies of species. Combining the perspectives of these different approaches suggests that an integrated phylogenomic approach will be beneficial. 相似文献
60.
The Air noncoding RNA epigenetically silences transcription by targeting G9a to chromatin 总被引：1，自引：0，他引：1
Nagano T Mitchell JA Sanz LA Pauler FM Ferguson-Smith AC Feil R Fraser P 《Science (New York, N.Y.)》2008,322(5908):1717-1720