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本研究对使用Vero细胞、RK13细胞或Vero/SLAM细胞从2000年~2007年山东省6个市风疹暴发和散发病例的咽拭子标本中所分离的风疹病毒,用RT-PCR方法扩增其E1基因的1107个核苷酸片段,并对其PCR产物进行序列测定和分析。结果提示,在基于WHO基因定型靶序列739个核苷酸片段构建的基因亲缘关系树上,16株风疹病毒株分属三个基因型:1E(12株)、1F(1株)和2A(3株)。1E基因型于2001年在山东省首次检测到,并逐年成为我省风疹病毒流行的优势基因型,其中,2006~2007年间流行的1E基因型风疹病毒与2001年和2002年流行的1E基因型风疹病毒存在差异,但无明显的时间和地理分布倾向;1F基因型和2A基因型分别于2000年、2001年分离到,至2007年间未再出现;3株2A基因型风疹病毒与我国风疹疫苗株(BRDII)密切相关。16株风疹病毒大部分核苷酸的突变为无义突变,氨基酸序列高度保守,均无重要抗原位点的改变;山东省2001~2007年间分离的所有1E基因型风疹病毒在E1蛋白的第338位氨基酸发生相同突变(Leu338→Phe338),以往报道相同。 相似文献
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This study analyzed the publications of authors from Costa Rican institutions that were included in the Science Citation Index (SCI) during 1999-2001. Out of the 722 references detected, distributed in 328 journals, 90.7% corresponded to original research articles. The total productivity figures showed a moderately increasing trend, both in absolute and population-adjusted terms, in concordance with previous data recorded for the period 1980-1998. The contribution of Revista de Biología Tropical to these figures corresponded to 10.0%, 8.9%, and 19.1%, for the years 1999, 2000, and 2001, respectively. The subject distribution of articles followed a similar pattern to that described for 1980-1998, with a predominance of biomedical (33.3%) and biological (27.5%) sciences, followed by agronomical (15.5%) sciences, chemistry (13.6%), physics (5.0%), geological sciences (3.6%), and mathematics (1.5%). Citation analyses for individual publications (up to July 15, 2002) revealed that only 45.2% of the articles had been cited at least once. The ten most cited references were analyzed, varying from 26 to 114 citations. The average citation per article was 2.60, and the average number of authors per article was 2.92. In agreement with data from 1980-1998, the University of Costa Rica appeared as the institution with highest productivity of SCI publications during 1999-2001, with a contribution of 50.0%. The percentage of publications performed without the participation of foreign co-authors showed a change in its decreasing trend of 1980-1998, stabilizing near the range of 25-30% during the period 1999-2001. 相似文献
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《Cell research》2002,(Z2)
AKIRE Shi Zuo…………………..1994;4:191.200AKOPOV SB…………………….1998;8:195-207AN Li Guo……………………….1999;9:281—290AN W_ei……………………………1999;9:37-49AN W_ei………………………….1999;9:225-235AN Zhu Ping……………………….1994;4:79—87ARAKI Satohiko………………….1999;9:237—242ARORA Kavita…………………..1994;4:117-125BAEHRECKE Eric H……………2000;10:193—204BAI Y0ng Yan……………………….1990;1:1一10BAI Y0ng Yan……………………..1996;6:65.73BAI Y0ng… 相似文献
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Background
There exists a lack of knowledge regarding the quantity and quality of scientific yield in relation to individual cancer types. We aimed to measure the proportion, quality and relevance of oncology-related articles, and to relate this output to their associated disease burden. By incorporating the impact factor(IF) and Eigenfactor™(EF) into our analysis we also assessed the relationship between these indices and the output under study.Methods
All publications in 2007 were retrieved for the 26 most common cancers. The top 20 journals ranked by IF and EF in general medicine and oncology, and the presence of each malignancy within these titles was analysed. Journals publishing most prolifically on each cancer were identified and their impact assessed.Principal Findings
63260 (PubMed) and 126845 (WoS) entries were generated, respectively. 26 neoplasms accounted for 25% of total output from the top medical publications. 5 cancers dominated the first quartile of output in the top oncology journals; breast, prostate, lung, and intestinal cancer, and leukaemia. Journals associated with these cancers were associated with much higher IFs and EFs than those journals associated with the other cancer types under study, although these measures were not equivalent across all sub-specialties. In addition, yield on each cancer was related to its disease burden as measured by its incidence and prevalence.Conclusions
Oncology enjoys disproportionate representation in the more prestigious medical journals. 5 cancers dominate yield, although this attention is justified given their associated disease burden. The commonly used IF and the recently introduced EF do not correlate in the assessment of the preeminent oncology journals, nor at the level of individual malignancies; there is a need to delineate between proxy measures of quality and the relevance of output when assessing its merit. These results raise significant questions regarding the best method of assessment of research and scientific output in the field of oncology. 相似文献15.
Biodiversity and Conservation - The rapid extinction of endangered plants (EPs) may lead to the destruction of entire ecosystems, which will seriously threaten the survival and development of... 相似文献
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This review focuses on some of the 'hot topics' that fall under the general heading 'mitochondria and aging'. For each selected topic, we highlight recent publications that have either addressed specific problems within the field or presented novel findings of interest regarding the links between mitochondria and aging. These include studies on the structure of complex I and the mechanisms of superoxide production by this complex; work showing a novel site of hydrogen peroxide production within mitochondria that is modulated by caloric restriction; explorations of the relationship between the rate of evolution of mitochondrial DNA and lifespan; a demonstration that mitochondrial DNA mutations do not limit lifespan in mice; and investigations of the effects of mitochondrial fission on aging. We also list other relevant articles of interest and suggest some key challenges for the field in the near future. 相似文献
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《Cell research》2002,(Z2)
31P NMR fnuclear magenetic resonancel………. ......……................….…1992;2:129.137‘~Ca2 accumulation.….……....…..1998;8:41.5097 KDa residual protein…….....…....1992;2:1-13 Agrobacterium tumefaciens.…….….…1990;1:1—10Acanthopanax brachypus...............1997;7:99.106AIlium sativt//D.…….....…….....1995;5:155.164A111tim cepa...............……...…1992:2:153,163Arabidopsis thallana...……....…..1996;6:125.136Arabidopsis……….……….…....1998;8:119.134aberrant di&ren… 相似文献
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Straume T Amundson SA Blakely WF Burns FJ Chen A Dainiak N Franklin S Leary JA Loftus DJ Morgan WF Pellmar TC Stolc V Turteltaub KW Vaughan AT Vijayakumar S Wyrobek AJ 《Radiation research》2008,170(3):393-405
A summary is provided of presentations and discussions at the NASA Radiation Biomarker Workshop held September 27-28, 2007 at NASA Ames Research Center in Mountain View, CA. Invited speakers were distinguished scientists representing key sectors of the radiation research community. Speakers addressed recent developments in the biomarker and biotechnology fields that may provide new opportunities for health-related assessment of radiation-exposed individuals, including those exposed during long-duration space travel. Topics discussed included the space radiation environment, biomarkers of radiation sensitivity and individual susceptibility, molecular signatures of low-dose responses, multivariate analysis of gene expression, biomarkers in biodefense, biomarkers in radiation oncology, biomarkers and triage after large-scale radiological incidents, integrated and multiple biomarker approaches, advances in whole-genome tiling arrays, advances in mass spectrometry proteomics, radiation biodosimetry for estimation of cancer risk in a rat skin model, and confounding factors. A summary of conclusions is provided at the end of the report. 相似文献