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   1672篇
  免费   97篇
  国内免费   4篇
  2023年   18篇
  2022年   46篇
  2021年   121篇
  2020年   76篇
  2019年   95篇
  2018年   71篇
  2017年   50篇
  2016年   73篇
  2015年   89篇
  2014年   106篇
  2013年   135篇
  2012年   119篇
  2011年   121篇
  2010年   57篇
  2009年   55篇
  2008年   69篇
  2007年   56篇
  2006年   49篇
  2005年   52篇
  2004年   47篇
  2003年   35篇
  2002年   34篇
  2001年   8篇
  2000年   13篇
  1999年   11篇
  1998年   9篇
  1997年   8篇
  1995年   4篇
  1994年   10篇
  1993年   8篇
  1992年   4篇
  1991年   11篇
  1990年   8篇
  1989年   8篇
  1988年   5篇
  1987年   7篇
  1986年   7篇
  1984年   7篇
  1983年   3篇
  1982年   7篇
  1981年   4篇
  1980年   9篇
  1979年   11篇
  1978年   3篇
  1977年   8篇
  1976年   3篇
  1975年   3篇
  1974年   6篇
  1973年   2篇
  1972年   6篇
排序方式: 共有1773条查询结果,搜索用时 15 毫秒
171.
Pollen beetles (Meligethes aeneus) and cabbage seed weevils (Ceutorhynchus assimilis) are major pests of oilseed rape (Brassica napus) throughout Europe. In field cage experiments in both winter and spring rape, honey bees (Apis mellifera) effectively transported the entomopathogenic fungus Metarhizium anisopliae to the flowers, causing infection and mortality of both adult and larval pollen beetles, as well as of adult seed weevils. External conidiation was observed on many of the dead pest insects. Although some external conidiation also occurred on dead honey bees, reduction in honey bee colony size during the experiments appeared unrelated to the fungus. The potential of this technique for integration into pest management strategies for the crop, particularly in association with a trap crop, is discussed.  相似文献   
172.
We isolated and characterized a cluster of platypus DMRT genes and compared their arrangement, location, and sequence across vertebrates. The DMRT gene cluster on human 9p24.3 harbors, in order, DMRT1, DMRT3, and DMRT2, which share a DM domain. DMRT1 is highly conserved and involved in sexual development in vertebrates, and deletions in this region cause sex reversal in humans. Sequence comparisons of DMRT genes between species have been valuable in identifying exons, control regions, and conserved nongenic regions (CNGs). The addition of platypus sequences is expected to be particularly valuable, since monotremes fill a gap in the vertebrate genome coverage. We therefore isolated and fully sequenced platypus BAC clones containing DMRT3 and DMRT2 as well as DMRT1 and then generated multispecies alignments and ran prediction programs followed by experimental verification to annotate this gene cluster. We found that the three genes have 58-66% identity to their human orthologues, lie in the same order as in other vertebrates, and colocate on 1 of the 10 platypus sex chromosomes, X5. We also predict that optimal annotation of the newly sequenced platypus genome will be challenging. The analysis of platypus sequence revealed differences in structure and sequence of the DMRT gene cluster. Multispecies comparison was particularly effective for detecting CNGs, revealing several novel potential regulatory regions within DMRT3 and DMRT2 as well as DMRT1. RT-PCR indicated that platypus DMRT1 and DMRT3 are expressed specifically in the adult testis (and not ovary), but DMRT2 has a wider expression profile, as it does for other mammals. The platypus DMRT1 expression pattern, and its location on an X chromosome, suggests an involvement in monotreme sexual development.  相似文献   
173.
174.
175.
Journal of Plant Growth Regulation - The field experiment was conducted to investigate the effects of applying urea with nitrification inhibitor (NI) (Nitrapyrine) alone or in combination with...  相似文献   
176.
Molecular Biology Reports - Celiac disease (CeD) and inflammatory bowel disease (IBD) are accompanied by impaired immune responses. To study the immune regulation of these diseases, we evaluated...  相似文献   
177.
Molecular Biology Reports - The present study aimed to evaluate the expression of the chemokine CXCL8 in both mRNA and protein levels in the serum, follicular fluid (FF), and cumulus cells (CCs)...  相似文献   
178.
179.
180.
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