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   13442篇
  免费   1034篇
  国内免费   839篇
  15315篇
  2024年   29篇
  2023年   137篇
  2022年   331篇
  2021年   602篇
  2020年   368篇
  2019年   485篇
  2018年   427篇
  2017年   332篇
  2016年   491篇
  2015年   822篇
  2014年   878篇
  2013年   1051篇
  2012年   1219篇
  2011年   1041篇
  2010年   637篇
  2009年   567篇
  2008年   775篇
  2007年   606篇
  2006年   613篇
  2005年   488篇
  2004年   413篇
  2003年   346篇
  2002年   289篇
  2001年   269篇
  2000年   222篇
  1999年   215篇
  1998年   155篇
  1997年   126篇
  1996年   135篇
  1995年   129篇
  1994年   115篇
  1993年   94篇
  1992年   134篇
  1991年   117篇
  1990年   81篇
  1989年   102篇
  1988年   60篇
  1987年   48篇
  1986年   58篇
  1985年   64篇
  1984年   18篇
  1983年   24篇
  1982年   28篇
  1981年   12篇
  1980年   25篇
  1979年   20篇
  1978年   16篇
  1977年   19篇
  1974年   9篇
  1972年   13篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
995.
996.
Mucosal tissues in the human female reproductive tract (FRT) are primary sites for both gynecological cancers and infections by a spectrum of sexually transmitted pathogens, including human immunodeficiency virus (HIV), that compromise women''s health. While the regulation of innate and adaptive immune protection in the FRT by hormonal cyclic changes across the menstrual cycle and pregnancy are being intensely studied, little to nothing is known about the alterations in mucosal immune protection that occur throughout the FRT as women age following menopause. The immune system in the FRT has two key functions: defense against pathogens and reproduction. After menopause, natural reproductive function ends, and therefore, two overlapping processes contribute to alterations in immune protection in aging women: menopause and immunosenescence. The goal of this review is to summarize the multiple immune changes that occur in the FRT with aging, including the impact on the function of epithelial cells, immune cells, and stromal fibroblasts. These studies indicate that major aspects of innate and adaptive immunity in the FRT are compromised in a site‐specific manner in the FRT as women age. Further, at some FRT sites, immunological compensation occurs. Overall, alterations in mucosal immune protection contribute to the increased risk of sexually transmitted infections (STI), urogenital infections, and gynecological cancers. Further studies are essential to provide a foundation for the development of novel therapeutic interventions to restore immune protection and reverse conditions that threaten women''s lives as they age.  相似文献   
997.
998.
999.
1000.
The genus Dichocarpum is endemic to East Asia, and many species have been used to treat various diseases. However, phytochemical researches of this genus have been limited to date. In the present study, a metabolomic approach based on UPLC-Q-TOF-MS/MS was used to explore the phytochemical profiles of 10 Chinese Dichocarpum species, and cannabinoid receptor (CB1/CB2) agonistic activities evaluation of these plants was performed. A total of 128 features were putatively annotated, belonging to alkaloids, flavonoids, triterpenes saponins, phenolic acids, and others. Semi-quantitative statistics demonstrated that alkaloids and flavonoids were widely distributed, with the former the most abundant, whereas triterpenes saponins were mainly distributed in D. fargesii and D. wuchuanense. The phylogenetic results obtained from DNA sequencing assigned the 10 species to three groups. Further results of in silico annotation revealed three chemical families and helped determine the characteristic features of the three groups. In addition, the plant extracts of nine species from this genus showed agonistic activity on CB2 receptors. This comprehensive analysis revealed the chemotype distribution and pharmacophylogenetic relationship, to provide clues for the prospective resource utilization of the medicinal plants from the genus Dichocarpum.  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