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   7303篇
  免费   297篇
  国内免费   5篇
  7605篇
  2023年   63篇
  2022年   74篇
  2021年   100篇
  2020年   151篇
  2019年   154篇
  2018年   242篇
  2017年   258篇
  2016年   253篇
  2015年   190篇
  2014年   231篇
  2013年   885篇
  2012年   411篇
  2011年   359篇
  2010年   221篇
  2009年   235篇
  2008年   292篇
  2007年   327篇
  2006年   256篇
  2005年   207篇
  2004年   221篇
  2003年   200篇
  2002年   155篇
  2001年   129篇
  2000年   127篇
  1999年   114篇
  1998年   75篇
  1997年   61篇
  1996年   51篇
  1995年   54篇
  1994年   55篇
  1993年   54篇
  1992年   56篇
  1991年   47篇
  1990年   70篇
  1989年   52篇
  1988年   51篇
  1987年   57篇
  1986年   62篇
  1985年   60篇
  1984年   63篇
  1983年   57篇
  1982年   40篇
  1981年   46篇
  1980年   48篇
  1979年   59篇
  1978年   49篇
  1976年   51篇
  1975年   60篇
  1974年   63篇
  1973年   46篇
排序方式: 共有7605条查询结果,搜索用时 15 毫秒
201.
The variation in the speed of conduction of motor fibers of the ulnar nerve was determined by Hopf's double-stimulus method and compared with values obtained from the duration of muscular response potentials for differently spaced points of stimulation. However, the values obtained from the difference of the duration of response potentials are inadequate since the duration of potentials cannot always be determined accurately. After a ten-day administration of faustan (15 mg per day) or phenytoin (300 mg per day) there was observed a decrease especially in the minimum rate of conduction of motor fibers of the ulnar nerve.  相似文献   
202.
203.
The present study examined whether or not certain anorexic agents produced flavor aversions. Rats showed comparable anorexia when injected with lithium chloride, ammonium sulfate, arginine·HCl, and d-glucose. Only lithium chloride produced a flavor aversion to either a novel liquid or food. Only arginine was found to interfere with the formation or recall of an association. The effects of the other chemicals were discussed in terms of the relationship between anorexia and induced sickness.  相似文献   
204.
Negotiations were conducted to investigate the effects on settlement-points andon the attitudes and perceptions of participants of (i) group participation and (ii)belief in own group's point of view, in a 2 × 2 factorial design. Ninety-six school children prepared cases in groups of four before representing their group's position against an individual of a similarly prepared opposed group. Group participation was manipulated by groups either participating in preparatory discussions or observing video films of another group's discussions. Belief was manipulated by systematically varying the composition of groups according to scores on a pre-test of attitudes towards the raising of the school-leaving age. In general the belief manipulation operated as expected, ‘believers’ exhibiting less variability, more tit-for-tat agreements and less opinion change than the ‘disbelievers’. Group participation did not influence the measures as predicted, and measures of interpersonal perception did not conform to the pattern of findings in recent experiments on intergroup discrimination. The results are discussed in terms of (i) their relevance to the issue of the appropriate relationship of the representative to his group in a negotiation and (ii) their implications for intergroup relations theory.  相似文献   
205.
The construction of a simple thermistor respiration-transducer support assembly, which allows the monitoring of respiration in human subjects without the discomfort often associated with more traditional attachment methods, is described.  相似文献   
206.
Regional cerebral glucose metabolism in aphemia: A case report   总被引:1,自引:0,他引:1  
Local cerebral metabolism was determined in a patient suffering aphemia following cerebral infarction using the 18FDG-PET technique. The syndrome was characterized by profound ictal nonfluency with sparing of other language functions. Speech subsequently improved so that content and grammar were appropriate but mild dysprosody persisted. Conventional CT showed no lesion of the left hemisphere while PET revealed a discrete focus of hypometabolism on the left which partially resolved on serial studies. The metabolic lesion could be localized to the region of the inferior precentral gyrus and the adjacent subcortical space.  相似文献   
207.
208.
209.
210.
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