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   56949篇
  免费   1456篇
  国内免费   20篇
  2020年   418篇
  2019年   510篇
  2018年   3983篇
  2017年   3345篇
  2016年   2879篇
  2015年   743篇
  2014年   714篇
  2013年   3095篇
  2012年   1673篇
  2011年   3483篇
  2010年   3170篇
  2009年   2187篇
  2008年   2677篇
  2007年   3090篇
  2006年   1006篇
  2005年   1077篇
  2004年   983篇
  2003年   944篇
  2002年   864篇
  2001年   1332篇
  2000年   1289篇
  1999年   960篇
  1998年   478篇
  1997年   409篇
  1996年   378篇
  1995年   368篇
  1994年   373篇
  1993年   360篇
  1992年   800篇
  1991年   765篇
  1990年   729篇
  1989年   655篇
  1988年   625篇
  1987年   629篇
  1986年   599篇
  1985年   669篇
  1984年   529篇
  1983年   431篇
  1981年   360篇
  1979年   518篇
  1978年   404篇
  1977年   391篇
  1976年   360篇
  1975年   461篇
  1974年   471篇
  1973年   511篇
  1972年   405篇
  1968年   412篇
  1967年   358篇
  1966年   420篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
851.
The subjects were divided into three groups with respect to their expectations concerning a recall task given after the final trial of the usual STM distractor procedure. Group 1 were told only that they would have to recall during each trial's recall interval, thus did not expect to have to recall again. Group 2 were told that they would have to recall all the words presented in the experiment at the end of the last trial, in addition to the trial-by-trial recall. Group 3 were told only that they would have to recall after all words had been presented and they sat passively through the presentation trials. In addition to their recall expectations, half of the subjects in each group received a 2-s presentation and half received a 5-s presentation interval. It was found that the length of the presentation interval had an effect on the number of words recalled at the end of all trials, but recall expectancy did not. However, expectancy did determine the rehearsal strategies of subjects and hence the serial positions from which items were recalled.  相似文献   
852.
An ann-out-of-water response was conditioned as an operant inOctopus cyaneus Gray. The response was limited to a vertical tube, 2.54 em i.d, Photoresistive sensors, illuminated with modulated light arranged around the tube above the waterline, detect the presence of an opaque object in the tube. The signal from this response detector is amplified and used to initiate a commercial motor-driven universal feeder according to the reinforcement schedule maintained by the logic control circuit. A sample cumulative record for perfonnance on a CRF schedule is given.  相似文献   
853.
854.
The author examines the criticisms of counselors which center on such factors as age, sex, race, and elitism. Areas of confusion regarding the functions of the counselor are related to the teacher-counselor issue, the professional functions of the counselor, and the basic purpose of counseling. The counselor is seen primarily as doing psychological counseling with individuals and groups, rather than teaching or advising.  相似文献   
855.
Two experiments were carried out, employing a computer-based cathode-ray tube display system, to study further the effects of sub-span Hst length, i.e., two, three, four, and five decimal digits, and relatively small interstimulus interval (ISI) values, i.e., 20, 40, 60, 80, and 100 msec, on visual information processing, storage, and retrieval mechanisms. The results of the first experiment confirmed the compttcated intenctions found in two earlier studies between Hst length and ISI values, but with much smaller ISI values than employed preriousfy. The results of the second experiment, in which unequal ISI values were employed within the same length input string, showed little effect resulting from this parameter, but it was suggested that a wider distribution of different ISI values within the same length input string would produce very strong effects.  相似文献   
856.
857.
858.
859.
860.
Nature of love--simplified   总被引:1,自引:0,他引:1  
  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