首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   191篇
  免费   3篇
  国内免费   3篇
安全科学   1篇
废物处理   5篇
环保管理   7篇
综合类   111篇
基础理论   43篇
污染及防治   22篇
评价与监测   5篇
社会与环境   2篇
灾害及防治   1篇
  2023年   4篇
  2021年   4篇
  2017年   3篇
  2016年   4篇
  2015年   2篇
  2014年   6篇
  2013年   8篇
  2012年   7篇
  2011年   10篇
  2010年   6篇
  2009年   5篇
  2008年   5篇
  2007年   7篇
  2006年   8篇
  2005年   2篇
  2004年   5篇
  2003年   2篇
  2002年   5篇
  2001年   5篇
  2000年   2篇
  1999年   2篇
  1998年   2篇
  1997年   4篇
  1992年   2篇
  1976年   1篇
  1975年   1篇
  1974年   1篇
  1968年   2篇
  1966年   1篇
  1965年   2篇
  1964年   4篇
  1963年   6篇
  1962年   5篇
  1961年   5篇
  1960年   7篇
  1959年   3篇
  1958年   1篇
  1957年   2篇
  1955年   5篇
  1954年   9篇
  1953年   6篇
  1951年   4篇
  1950年   2篇
  1949年   1篇
  1947年   2篇
  1939年   2篇
  1938年   1篇
  1937年   1篇
  1933年   1篇
  1927年   1篇
排序方式: 共有197条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
65.
66.
67.
68.
69.
Human noroviruses (HuNoV) are amongst the leading causes of acute non-bacterial gastroenteritis in humans and can be transmitted via person-to-person contact, via contact with contaminated surfaces or by consumption of contaminated food. Contaminated surfaces in healthcare settings contribute to the transmission of viruses. No-touch automated room disinfection systems might prevent such a spread of contamination and thus their virucidal effect needs to be evaluated. The aim of this study was to assess the efficacy of a nebulization system spraying hydrogen peroxide on two main surrogates of HuNoV, namely murine norovirus (MNV) and feline calicivirus (FCV). The viruses were dried on cover glasses and on stainless steel discs and exposed to nebulization. The number of infectious viral particles and genomic copies before and after the nebulization was compared. The efficacy in reducing infectivity of both surrogates was demonstrated. For the infectious viral titre of MNV and FCV, a log10 reduction factor ≥4.84 and 4.85 was observed after nebulization, respectively, for tests on cover glasses and ≥3.90 and 5.30, respectively, for tests on stainless steel discs. Only low reductions in genomic copy numbers were observed for both surrogates. The nebulization of hydrogen peroxide showed a clear virucidal effect on both HuNoV surrogates, MNV and FCV, on two different carriers and the use of nebulization should be promoted in complementarity with conventional disinfection methods in healthcare settings and food processing facilities to reduce viral load and spread of contamination.  相似文献   
70.
The use of conservation translocations to mitigate human effects on biodiversity is increasing, but how these efforts are allocated remains unclear. Based on a comprehensive literature review and online author survey, we sought to determine the goals of translocation efforts, whether they focus on species and regions with high threat and likelihood of perceived success, and how success might be improved. We systematically searched the ISI Web of Knowledge and Academic Search Complete databases to determine the species and regions of conservation translocations and found 1863 articles on conservation translocations in the United States, Canada, Mexico, Central America, and Caribbean published from 1974 to 2013. We questioned 330 relevant authors to determine the motivation for translocations, how translocations were evaluated, and obstacles encountered. Conservation translocations in North America were geographically widespread (in 21 countries), increased in frequency over time for all animal classes (from 1 in 1974 to 84 in 2013), and included 279 different species. Reintroductions and reinforcements were more common in the United States than in Canada and Mexico, Central America, or the Caribbean, and their prevalence was correlated with the number of species at risk at national and state or provincial levels. Translocated species had a higher threat status at state and provincial levels than globally (International Union for Conservation of Nature Red List categorization), suggesting that translocations may have been motivated by regional priorities rather than global risk. Our survey of authors was consistent with these results; most translocations were requested, supported, or funded by government agencies and downlisting species at national or state or provincial levels was the main goal. Nonetheless, downlisting was the least reported measure of success, whereas survival and reproduction of translocated individuals were the most reported. Reported barriers to success included biological factors such as animal mortality and nonbiological factors, such as financial constraints, which were less often considered in the selection of release sites. Our review thus highlights discrepancies between project goals and evaluation criteria and between risk factors considered and obstacles encountered, indicating room to further optimize translocation projects.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号