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   37183篇
  免费   833篇
  国内免费   15篇
  2021年   135篇
  2020年   239篇
  2019年   255篇
  2018年   3786篇
  2017年   3122篇
  2016年   2576篇
  2015年   475篇
  2014年   389篇
  2013年   1408篇
  2012年   1123篇
  2011年   3010篇
  2010年   2853篇
  2009年   1815篇
  2008年   2168篇
  2007年   2628篇
  2006年   427篇
  2005年   556篇
  2004年   515篇
  2003年   432篇
  2002年   389篇
  2001年   731篇
  2000年   751篇
  1999年   475篇
  1998年   199篇
  1997年   190篇
  1996年   146篇
  1995年   135篇
  1993年   139篇
  1992年   364篇
  1991年   321篇
  1990年   352篇
  1989年   335篇
  1988年   319篇
  1987年   289篇
  1986年   310篇
  1985年   298篇
  1984年   237篇
  1983年   203篇
  1979年   191篇
  1978年   162篇
  1975年   187篇
  1974年   241篇
  1973年   198篇
  1972年   203篇
  1971年   167篇
  1970年   149篇
  1969年   199篇
  1968年   202篇
  1967年   161篇
  1966年   182篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
912.
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   
913.
914.
Failure to share household chores equitably may be a major cause of the high failure rate of experimental group-living arrangements. A behavioral approach to worksharing based on a point system was implemented in one experimental group and its most important components experimentally evaluated. Experiment I showed that awarding credits produced more work than not awarding credits. Experiment II showed that making credits contingent on the outcome of a detailed inspection produced more work than awarding credits noncontingently. Experiment III demonstrated that awarding rent reductions contingent on credit earnings produced more work than awarding rent reductions noncontingently. Other evaluative data suggest that the resulting living arrangement is cheaper, more effective, and more satisfactory to the residents when compared to the most popular alternative living arrangements.  相似文献   
915.
916.
Abstract.— A token economy program was applied on a ward for 12 chronic schizophrenic patients. An ABABC-design, i.e. a group reversal design with a noncontingent reinforcement phase at the end, was used to evaluate the treatment. The patients' activity-level increased from baseline to the treatment phase. During the reversal period the activity-level decreased but it increased again when the token economy was reintroduced. The non-contingent reinforcement resulted in the predicted decrease for two of the six behaviors recorded. Five of the twelve patients were discharged from the ward during the 8-month program period and none of them had been readmitted at the end of the one year follow-up. Individual treatment programs for two of the patients concerning aggressive acts, deficient eye-contact and lip-biting are described.  相似文献   
917.
Two levels of confinement duration (5 or 60 sec) in either startbox or goalbox were factorially combined with presence or absence of shock during extinction of a runway escape response in a self-punitive paradigm under a spaced-trials procedure. All groups were equated for amount and temporal spacing of handling before and after each trial. Shocked rats were more resistant to extinction than nonshocked rats only when startbox confinement was short. When startbox confinement was long, shock facilitated extinction. Long goalbox confinement enhanced running speed for shocked rats, but only in the presence of shock. It was suggested that duration of startbox confinement affects strength of conditioned fear, with long confinement leading to its extinction.  相似文献   
918.
Key pecking and treadle pressing in pigeons were compared under concurrent (key-treadle) and single-operant differential-reinforcement-of-low-rate schedules of food reinforcement ranging from 5 to 60 sec (concurrent procedure) or 5 to 120 sec (single-operant procedure). Under both procedures, the two operants followed the same general law: decreasing response rate and reinforcement rate and increasing number of responses per reinforcement as a function of increasing schedule interval. High correlations were found between key pecking and treadle pressing for the measures of response rate, reinforcement rate, and responses per reinforcement. Regression equations allowed the prediction of treadle pressing from key pecking. More bursting occurred in responding to the key, and key pecking showed a more precise temporal discrimination than treadle pressing. A test for sequential dependencies between key and treadle responses showed significant dependencies not only under the concurrent procedure but also in data created artificially by merging key and treadle sequences from different pigeons under the concurrent procedure and from the same pigeon under the single-operant procedure. It seems likely that the sequential dependencies found were due to the independent action of the schedule on each operant and that behavioral dependencies did not occur with the concurrent training procedure. The key-peck operant does not appear to have any special qualities that preclude its use in discovering general laws of behavior, at least under the differential-reinforcement-of-low-rate schedule. The usefulness of the key peck in other situations requires direct experimental study.  相似文献   
919.
The stages of acquisition in stimulus fading   总被引:1,自引:1,他引:0       下载免费PDF全文
Pigeons were exposed to a stimulus fading procedure in which control of responding was transferred from red and black stimuli to lines of different angular orientation. After superimposing one line on the red stimulus and the other line on the black stimulus, the intensity of the lines was gradually increased and that of the red stimulus was gradually reduced. Probes consisting of red and line stimuli presented separately were used during the course of fading to assess control exerted by each element of the compound. As the lines were faded in, they did not acquire control of responding. As red was faded out, control of responding was acquired first by the lower intensity red stimuli in combination with the line stimulus, and finally by the angular orientation of the lines. Probes also determined the point at which the line stimuli, presented alone, would maintain a high degree of stimulus control. The results demonstrated that new stimuli in fading acquire dimensional control of responding in two sequential stages. Acquisition of stimulus control in fading was explained in terms of attenuation of stimulus blocking.  相似文献   
920.
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