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   4722篇
  免费   240篇
  国内免费   23篇
  2023年   70篇
  2022年   66篇
  2021年   106篇
  2020年   92篇
  2019年   85篇
  2018年   182篇
  2017年   157篇
  2016年   201篇
  2015年   148篇
  2014年   215篇
  2013年   334篇
  2012年   320篇
  2011年   356篇
  2010年   213篇
  2009年   148篇
  2008年   212篇
  2007年   237篇
  2006年   207篇
  2005年   215篇
  2004年   208篇
  2003年   238篇
  2002年   163篇
  2001年   113篇
  2000年   124篇
  1999年   90篇
  1998年   31篇
  1997年   25篇
  1996年   17篇
  1993年   9篇
  1992年   22篇
  1991年   31篇
  1990年   13篇
  1989年   19篇
  1988年   25篇
  1987年   20篇
  1986年   14篇
  1985年   23篇
  1984年   14篇
  1983年   13篇
  1982年   14篇
  1981年   10篇
  1979年   15篇
  1978年   10篇
  1977年   10篇
  1975年   17篇
  1974年   15篇
  1973年   16篇
  1972年   10篇
  1971年   14篇
  1966年   9篇
排序方式: 共有4985条查询结果,搜索用时 0 毫秒
1.
The authors have studied in the dog--normal or diabetic insipidus after hypothalamic lesion--submitted to oral ingestion of ethanol the effects of a few antidiuretic drug: chlorpropamid, atromid-S, carbamazepin and carisoprodol. The carisoprodol only can reduce the diuresis and the drinking provoked by ethanol.  相似文献   
2.
We isolated a recombinant H9N2 avian influenza virus (AIV) from fresh egret feces in the Ardeidae protection region of the Dongting Lake wetland area in China, and it was designated A/Egret/Hunan/1/2012(H9N2). This is the first report of isolating H9N2 AIV from wild birds in the Dongting Lake wetland. Its eight gene segments are generated by reassortment of gene segments of different AIV subtypes. These results are helpful for understanding the epidemiology and evolution of AIV in wild birds during migration.  相似文献   
3.
4.
Allopatric isolation in glacial refugia has caused differentiation and speciation in many taxa globally. In this study, we investigated the nuclear and mitochondrial genetic differentiation of the long fingered bat, Myotis capaccinii during the ice ages in south-eastern Europe and Anatolia. The mitochondrial DNA (mtDNA) analyses indicated a suture zone similar to those recorded in other animal species, including bats, suggesting the association of more than one refugium with the region. Contrary to most of the other species where a suture zone was seen in Anatolia, for M. capaccinii the geographical location of the genetic break was in south-eastern Europe. This mitochondrial differentiation was not reflected in the nuclear microsatellites, however, suggesting that the lack of contact during the ice ages did not result in reproductive isolation. Hence taxonomically, the two mitochondrial clades cannot be treated as separate species.  相似文献   
5.
6.
A complex of immunological cell tests with M. pneumoniae antigen (the lymphocyte blast-cell transformation test, the allergic neutrophil alteration test) was carried out in order to establish the correlation between the results of positive seroconversion and the sepcific immunological reactivity of lymphoid cells in pneumonia patients. Mycoplasmic cutireactive allergen, when used for the accelerated diagnosis of mycoplasmic pneumonia in humans, was shown to be specific and safe. Cuti-allergic tests with mycoplasmic allergen allowed to diagnose mycoplasmic pneumonia at early stages (beginning from days 5--7), which ensures the possibility of indicating etiotropic treatment to patients in due time.  相似文献   
7.
8.
9.
10.
Cerebrohepatorenal malformation is a rare familial disorder characterized by typical renal lesions combined with Dandy-Walker malformation, and congenital hepatic fibrosis. In this case report, a male premie with the diagnosis of cerebrorenal syndrome or so called Goldston syndrome is presented. Besides the rarity of this syndrome, this case is the second reported patient diagnosed prenatally.  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