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   563篇
  免费   40篇
  国内免费   5篇
耳鼻咽喉   4篇
儿科学   23篇
妇产科学   12篇
基础医学   90篇
口腔科学   29篇
临床医学   51篇
内科学   121篇
皮肤病学   21篇
神经病学   18篇
特种医学   10篇
外科学   84篇
综合类   10篇
一般理论   2篇
预防医学   33篇
眼科学   28篇
药学   38篇
中国医学   3篇
肿瘤学   31篇
  2023年   8篇
  2022年   13篇
  2021年   27篇
  2020年   19篇
  2019年   17篇
  2018年   22篇
  2017年   16篇
  2016年   11篇
  2015年   22篇
  2014年   21篇
  2013年   23篇
  2012年   38篇
  2011年   30篇
  2010年   32篇
  2009年   7篇
  2008年   27篇
  2007年   27篇
  2006年   27篇
  2005年   22篇
  2004年   27篇
  2003年   23篇
  2002年   22篇
  2001年   10篇
  2000年   5篇
  1999年   9篇
  1998年   8篇
  1997年   6篇
  1996年   6篇
  1995年   3篇
  1994年   2篇
  1993年   2篇
  1992年   12篇
  1991年   8篇
  1990年   5篇
  1989年   4篇
  1988年   7篇
  1987年   5篇
  1986年   3篇
  1984年   3篇
  1983年   3篇
  1982年   2篇
  1981年   2篇
  1980年   2篇
  1977年   5篇
  1976年   3篇
  1974年   4篇
  1973年   1篇
  1972年   1篇
  1971年   2篇
  1967年   1篇
排序方式: 共有608条查询结果,搜索用时 15 毫秒
1.
The postnatal development of alcohol dehydrogenase (ADH) isozymes was studied in liver, kidney, stomach and eye tissues of C57BL/6J inbred male mice using agarose isoelectric focusing and histochemical methods. Development profiles were tissue specific, with adult patterns being attained by 30 days in the liver and stomach, and by 42 days in the kidneys. Ocular ADH-C2 increased in activity at the end of the first week, corresponding to the time of eye opening in the neonate.  相似文献   
2.
Intradural cavernomas are rare vascular lesions of the spinal cord. Four cases of histologically verified cavernomas of the cord are reported, of which two were extramedullary and two were intramedullary in location. Progressive neurological deficit was the presenting feature in three cases while one patient had a rapid evolution of neurological deficits and was found at surgery to have had bled from the extramedullary lesion. All the patients were subjected to surgery and total excision of the cavernomas was carried out in each case. While two patients improved after surgery the other two remained static. The available literature on spinal cord cavernomas is reviewed.  相似文献   
3.
4.
5.
Questionnaires assessing levels of job satisfaction and possible sources of stress were distributed to a random sample of general practitioners in the Greater Manchester area. The highest levels of job satisfaction were reported for `intrinsic' job factors such as freedom to choose method of working, amount of responsibility and amount of variety, rather than `extrinsic' factors such as rate of pay and hours of work. The main causes of stress appeared to be interruptions of various kinds. Factor analysis revealed four major sources of stress: interruptions; emotional involvement; administrative workload and work/home interface; and routine medical work. Of these, all but routine medical work were associated with job satisfaction. It is concluded that the major sources of stress for the general practitioner are not medical, but social.  相似文献   
6.
The kinetics and mechanism of the inhibiting action of toluene on the Ce(IV) initiated polymerization of acrylonitrile were studied together with the effects of [M], [Ce(IV)], [Toluene], [HClO4], [NaClO4], and [Acetic acid] on the rate of polymerization. The values of composite rate constant kkt/kpkoki for toluene (and substituted toluenes) was calculated by plotting [M]/Rp versus [M]?1. A very significant observation in the present study was that the plot of [M]/Rp versus [M]?1 gave a negative intercept, which seems to be a general observation for all inhibiting substrates. On the basis of the experimental data, it could be concluded that the benzyl radical obtained by hydrogen abstraction, and not a chain transfer, is responsible for the inhibition.  相似文献   
7.
Various clinical specimens were processed to find the prevalence rate of enterococci and to identify the species of clinical isolates of enterococci. Screening of various clinical specimens revealed that enterococci were prevalent in 2% of the total specimens, with urine and wound to be the major site of isolation. Conventional test scheme proposed by Facklam and Collins and commercially available systems Rapid ID 32 Strep (biomereiux) were successfully used to speciate enterococcal strains. Five species of enterococci were identified in the study from a set of 396 cultures, with E. faecalis (79.79%), and E. faecium (11.11%) predominating. E. hirae (3.03%), E. gallinarum (3.03%), and E. casseliflavus (3.03%), were the other members of Enterococcus species identified.  相似文献   
8.
Indomethacin, a nonsteroidal anti-inflammatory agent, will abolish salmonella-induced rabbit ileal secretion when given prior to the establishment of infection. In the present study, we assessed whether indomethacin can inhibit salmonella-induced intestinal secretion when administered after infection and net intestinal secretion are well established. A physiological model of salmonellosis, salmonella-infected rhesus monkeys, was used. This model also permitted an examination of the effects of indomethacin in both the small and large intestines. The effect of indomethacin in control monkeys was also studied. Indomethacin caused a striking enhancement of net intestinal water transport in the jejunum,, ileum, and colon of salmonella-infected monkeys. These effects occurred promptly and were of sufficient magnitude in the ileum and colon to cause a reversal in the direction of net transport from net secretion to net absorption. Indomethacin also enhanced net water transport in the jejunum ileum, and colon of normal animals. These data show that indomethacin markedly enhances net intestinal water transport in both the small and large intestines of salmonella-infected monkeys, even when administered after salmonella infection and intestinal secretion are well established. Similar enhancement also occurs in the normal intestine. The mechanism(s) by which indomethacin produces these effects is not known.  相似文献   
9.
10.
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