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   26138篇
  免费   874篇
  国内免费   12篇
  27024篇
  2019年   252篇
  2018年   316篇
  2017年   346篇
  2016年   391篇
  2015年   310篇
  2014年   337篇
  2013年   1889篇
  2012年   641篇
  2011年   658篇
  2010年   414篇
  2009年   434篇
  2008年   617篇
  2007年   557篇
  2006年   495篇
  2005年   483篇
  2004年   451篇
  2003年   458篇
  2002年   472篇
  2001年   705篇
  2000年   684篇
  1999年   475篇
  1998年   254篇
  1992年   471篇
  1991年   456篇
  1990年   459篇
  1989年   466篇
  1988年   410篇
  1987年   424篇
  1986年   449篇
  1985年   487篇
  1984年   413篇
  1983年   379篇
  1982年   276篇
  1981年   320篇
  1980年   244篇
  1979年   442篇
  1978年   320篇
  1977年   288篇
  1976年   279篇
  1975年   420篇
  1974年   459篇
  1973年   488篇
  1972年   414篇
  1971年   406篇
  1970年   381篇
  1969年   401篇
  1968年   501篇
  1967年   481篇
  1966年   455篇
  1958年   252篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
271.
272.
273.
Flicker fusion frequencies of 48 healthy controls and of 35 alcoholics were measured to detect possible associations between flicker fusion and signs of nonspecific brain damage, the aim of the study. FFF was statistically significantly lower in patients addicted to alcohol than in healthy subjects. Lower flicker fusion frequencies were associated with the severeness of organic psychosis as rated psychopathologically. The hypothesis that addiction to alcohol is a sign of diffuse, nonspecific, organic brain damage was discussed.  相似文献   
274.
Plasma concentrations of imipramine and amitriptyline and their desmethylated metabolites were measured in 20 children being treated for major depressive illness 2 wk. and 5 to 10 wk. after achieving drug dosages of 2.25 mg/kg body weight. At 2 wk. all children had exhibited clinical improvement, but by 10 wk. 4 of the 10 children treated with imipramine and 5 of the 10 children treated with amitriptyline had experienced clinical relapse of depressive symptoms. Tricyclic antidepressant plasma concentrations and ratios were comparable in the subgroups of children who maintained their clinical improvement and those who relapsed. There was no evidence of a systematic decline in plasma tricyclic antidepressant concentrations in those children who relapsed.  相似文献   
275.
Groups of 12 normal and insomniac male subjects aged 55 to 71 yr. were sleep deprived for 64 hr. In both groups, the sleep loss was preceded by four baseline sleep nights and followed by four recovery nights. Reaction time, immediate recall, sleepiness, and body temperature were measured at approximately 2300, 0115, 0330, 0530, and 0800 during baseline, deprivation and recovery nights. Significant performance or mood differences were not found between the normal and insomniac males on any measure or at any testing period throughout the study. Performance of both groups declined characteristically during sleep loss while subjective sleepiness increased. As in young adults, degraded performance was restored by 8 hr. of recovery sleep. However, subjective sleepiness did not return to baseline levels until early in the second recovery night. It was concluded that chronic insomnia does not result in group performance deficits similar to those seen after chronic sleep loss; and the restorative function of sleep operates as efficiently in older insomniac subjects (who apparently have reduced need to sleep) as in older normal subjects.  相似文献   
276.
Effects of presentation complexity on rapid-sequential reading   总被引:1,自引:0,他引:1  
  相似文献   
277.
278.
279.
280.
The authors present a short review of the pertinent literature and report on their own neuropsychiatric findings following internal craniocerebral injuries, at the same time drawing attention to the necessity of psychological examination. Statistical comparisons with the international literature are complicated owing to the different classifications used for craniocerebral injuries.  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