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   40019篇
  免费   619篇
  国内免费   2篇
  40640篇
  2020年   470篇
  2019年   579篇
  2018年   782篇
  2017年   846篇
  2016年   868篇
  2015年   630篇
  2014年   722篇
  2013年   3078篇
  2012年   1339篇
  2011年   1335篇
  2010年   882篇
  2009年   826篇
  2008年   1187篇
  2007年   1196篇
  2006年   1055篇
  2005年   949篇
  2004年   891篇
  2003年   842篇
  2002年   862篇
  2001年   1190篇
  2000年   1130篇
  1999年   886篇
  1998年   393篇
  1997年   387篇
  1996年   360篇
  1995年   374篇
  1993年   364篇
  1992年   742篇
  1991年   654篇
  1990年   707篇
  1989年   612篇
  1988年   647篇
  1987年   601篇
  1986年   612篇
  1985年   555篇
  1984年   510篇
  1983年   494篇
  1982年   358篇
  1979年   577篇
  1978年   408篇
  1975年   454篇
  1974年   498篇
  1973年   530篇
  1972年   401篇
  1971年   391篇
  1970年   351篇
  1969年   401篇
  1968年   475篇
  1967年   429篇
  1966年   354篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
891.
Ten male and 10 female subjects, half of whom were classified as “heavy” and half as “light” drinkers, ingested a 4-1 combination of tonic water and 80-proof vodka in an amount calculated to produce a state of moderate intoxication (average estimated peak blood alcohol level=.075). This resulted in an increased sensitivity (latency, magnitude, and duration) to the calorically induced “oculogyral illusion” (OGI) relative to a placebo (tonic water) condition. “Heavy” and “light” drinkers did not differ significantly on any of the measures. It was speculated that the alcoholic enhancement of the OGI was due either to a decreased ability to suppress vestibular nystagmus when attempting to fixate a visual stimulus or to the expenditure of extra-normal effort in order to maintain fixation.  相似文献   
892.
Experienced observers were asked to identify, in a four-level 2AFC situation, the longer of two unfilled time intervals, each of which was marked by a pair of 20-msec acoustic pulses. When all the markers were identical, high-level (186-dB SPL) bursts of coherently gated sinusoids or bursts of band-limited Gaussian noise, a change in the spectrum of the markers generally did not affect performance. On the other hand, for 1-kHz tone-burst markers, intensity decreases below 25 dB SL were accompanied by sizable deterioration of the discrimination performance, especially at short (25-msec) base intervals. Similarly large changes in performance were observed also when the two tonal markers of each interval were made very dissimilar from each other, either in frequency (frequency difference larger than 1 octave) or in intensity (level of the first marker at least 45 dB below the level of the second marker). Time-difference thresholds in these two latter cases were found to be nonmonotonically related to the base interval, the minima occurring between 40- and 80-msec onset separations.  相似文献   
893.
Reaction times were measured in a task which requires the subject to search a brief visual array for a critical letter embedded in a row of background letters. In Experiment 1, the position of a critical letter in an instructed reading order and the size of a set of memorized letters were varied. Mean reaction time increased monotonically with distance of the critical letter from the beginning of the instructed reading path in the display. The variables reading position and memory set size were additive in their effect on mean reaction time. Data from a second experiment in which the retinal location of the critical letter and its reading position were varied showed that both reading position and retinal location influenced mean reaction time, but the effect of reading position on reaction time was greater. These variables interacted.  相似文献   
894.
895.
896.
897.
898.
899.
L B Feldman 《Family process》1976,15(4):389-395
A family-systems model of depression is presented and discussed. In this model, the intrapsychic concept of cognitive schema and the interpersonal concepts of social stimulation and social reingorcement are integrated within a systems-theory perspective. The effects of positive and negative feedback are delineated, and a concept of depression-triggering and depression-maintaining feedback loops is described. A clinical illustration is utilized to exemplify the theoretical model.  相似文献   
900.
This study examined differences in vocational maturity of women across different levels of internal-external control and typical versus atypical vocational choice. It was predicted that internally controlled women would have higher vocational maturity scores than externally controlled women; women who make atypical vocational choices would have higher vocational maturity scores than women who make typical choices. Data from the Attitude Scale of Crites' Career Maturity Inventory, MacDonald and Tseng's I-E Scale, and dichotomized ratings of typical versus atypical vocational choice were obtained from 179 freshmen to senior female student volunteers in a large New England university. Analysis of variance indicated that internally controlled women had significantly higher vocational maturity than externally controlled women (p <. 01); no differences were found in vocational maturity between those making typical or atypical vocational choices; the lowest level of vocational maturity was found for externally controlled females making atypical vocational choices. Implications of these findings for counseling are discussed.  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