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排序方式: 共有1330条查询结果,搜索用时 31 毫秒
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Bradley D 《Science (New York, N.Y.)》2003,300(5628):2022-2023
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Isolation of a cDNA from the virus responsible for enterically transmitted non-A, non-B hepatitis 总被引:59,自引:0,他引:59
G R Reyes M A Purdy J P Kim K C Luk L M Young K E Fry D W Bradley 《Science (New York, N.Y.)》1990,247(4948):1335-1339
Major epidemic outbreaks of viral hepatitis in underdeveloped countries result from a type of non-A, non-B hepatitis distinct from the parenterally transmitted form. The viral agent responsible for this form of epidemic, or enterically transmitted non-A, non-B hepatitis (ET-NANBH), has been serially transmitted in cynomolgus macaques (cynos) and has resulted in typical elevation in liver enzymes and the detection of characteristic virus-like particles (VLPs) in both feces and bile. Infectious bile was used for the construction of recombinant complementary DNA libraries. One clone, ET1.1, was exogenous to uninfected human and cyno genomic liver DNA, as well as to genomic DNA from infected cyno liver. ET1.1 did however, hybridize to an approximately 7.6-kilobase RNA species present only in infected cyno liver. The translated nucleic acid sequence of a portion of ET1.1 had a consensus amino acid motif consistent with an RNA-directed RNA polymerase; this enzyme is present in all positive strand RNA viruses. Furthermore, ET1.1 specifically identified similar sequences in complementary DNA prepared from infected human fecal samples collected from five geographically distinct ET-NANBH outbreaks. Therefore, ET1.1 represents a portion of the genome of the principal viral agent, to be named hepatitis E virus, which is responsible for epidemic outbreaks of ET-NANBH. 相似文献
76.
Taylor FW Diner DJ Elson LS McCleese DJ Martonchik JV Delderfield J Bradley SP Schofield JT Gille JC Coffey MT 《Science (New York, N.Y.)》1979,205(4401):65-67
Further results from the Venus orbiter radiometric temperature experiment (VORTEX) on the Pioneer orbiter are presented. These are used to characterize the three-dimensional temperature field, the cloud structure, and the dynamics of the 60-to 130-kilometer altitude region of the Venus atmosphere. One of the new discoveries is a "dipole" structure at high latitudes, with two hot spots rotating around the pole, surrounded by banks of cold cloud. 相似文献
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Michel JB Shen YK Aiden AP Veres A Gray MK;Google Books Team Pickett JP Hoiberg D Clancy D Norvig P Orwant J Pinker S Nowak MA Aiden EL 《Science (New York, N.Y.)》2011,331(6014):176-182
We constructed a corpus of digitized texts containing about 4% of all books ever printed. Analysis of this corpus enables us to investigate cultural trends quantitatively. We survey the vast terrain of 'culturomics,' focusing on linguistic and cultural phenomena that were reflected in the English language between 1800 and 2000. We show how this approach can provide insights about fields as diverse as lexicography, the evolution of grammar, collective memory, the adoption of technology, the pursuit of fame, censorship, and historical epidemiology. Culturomics extends the boundaries of rigorous quantitative inquiry to a wide array of new phenomena spanning the social sciences and the humanities. 相似文献
78.
Outeiro TF Kontopoulos E Altmann SM Kufareva I Strathearn KE Amore AM Volk CB Maxwell MM Rochet JC McLean PJ Young AB Abagyan R Feany MB Hyman BT Kazantsev AG 《Science (New York, N.Y.)》2007,317(5837):516-519
The sirtuins are members of the histone deacetylase family of proteins that participate in a variety of cellular functions and play a role in aging. We identified a potent inhibitor of sirtuin 2 (SIRT2) and found that inhibition of SIRT2 rescued alpha-synuclein toxicity and modified inclusion morphology in a cellular model of Parkinson's disease. Genetic inhibition of SIRT2 via small interfering RNA similarly rescued alpha-synuclein toxicity. Furthermore, the inhibitors protected against dopaminergic cell death both in vitro and in a Drosophila model of Parkinson's disease. The results suggest a link between neurodegeneration and aging. 相似文献
79.
Rett syndrome is an autism spectrum disorder caused by mosaic expression of mutant copies of the X-linked MECP2 gene in neurons. However, neurons do not die, which suggests that this is not a neurodegenerative disorder. An important question for future therapeutic approaches to this and related disorders concerns phenotypic reversibility. Can viable but defective neurons be repaired, or is the damage done during development without normal MeCP2 irrevocable? Using a mouse model, we demonstrate robust phenotypic reversal, as activation of MeCP2 expression leads to striking loss of advanced neurological symptoms in both immature and mature adult animals. 相似文献
80.
Bradley HC 《Science (New York, N.Y.)》1904,19(474):196-197