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   2284篇
  免费   84篇
  国内免费   5篇
  2022年   12篇
  2020年   33篇
  2019年   28篇
  2018年   55篇
  2017年   53篇
  2016年   47篇
  2015年   37篇
  2014年   56篇
  2013年   294篇
  2012年   106篇
  2011年   113篇
  2010年   59篇
  2009年   57篇
  2008年   98篇
  2007年   92篇
  2006年   79篇
  2005年   82篇
  2004年   78篇
  2003年   76篇
  2002年   72篇
  2001年   38篇
  2000年   32篇
  1999年   36篇
  1998年   39篇
  1997年   31篇
  1996年   26篇
  1995年   32篇
  1994年   34篇
  1993年   36篇
  1992年   31篇
  1991年   22篇
  1990年   25篇
  1989年   22篇
  1988年   21篇
  1987年   19篇
  1986年   14篇
  1985年   25篇
  1984年   19篇
  1983年   28篇
  1982年   20篇
  1981年   18篇
  1980年   18篇
  1979年   19篇
  1978年   36篇
  1977年   27篇
  1976年   14篇
  1975年   22篇
  1974年   21篇
  1973年   16篇
  1972年   13篇
排序方式: 共有2373条查询结果,搜索用时 93 毫秒
991.
992.
993.
The relationship between punishment shock intensity and basal skin resistance (BSR) was investigated in two sessions with human females selected for their ability to maintain a fairly substantial operant rate under a wide range of shock intensities. In both sessions each button-pressing response was reinforced with a counter tally. Subjects were paid one cent for each 20 counts. In session 1, punishment followed each response during alternate 4-min periods; in session 2 punishment was programmed in all 4-min periods. Shock intensities were presented randomly among the 4-min shock periods, with the restriction that the first three presentations occurred in ascending order. Operant responding showed some suppression at higher shock intensities in session 1, with substantial recovery in most subjects during session 2. Respondent behavior was characterized by greater activity at successively higher intensities, with recovery at all shock levels, especially the lowest levels, apparent during the second session.  相似文献   
994.
In a double-blind cross-over design sixteen subjects took 50 mg of chlorpromazine or placebo in tablet form 2 hours prior to completing a dichotic listening and simple reaction time task with and without warnings. In the simple reaction time task, blocks of 80 stimuli were presented to each ear with and without warning cue under drug and placebo conditions. On the dichotic listening task the expected right ear advantage for reporting digits was obtained. While the drug had no main effect on the number of errors, there were more trials on which an ear advantage was present than in the placebo condition. In the reaction time task there were main effects of drug, warning cue and foreperiod: warnings facilitated reaction; chlorpromazine retarded reaction; and reaction times were most facilitated by warning foreperiods in excess of 1200ms. Several findings were of interest: On uncued trials, with placebo, right ear responses were faster than those for stimuli presented to the left ear. Drug also interacted with foreperiod duration. These results were interpreted in the light of Tucker and Williamson’s (1984) review of the role of Pribram and McGuinness’s Arousal and Activation sytems in lateralized behavior.  相似文献   
995.
Forty-one clinic-referred children were given the DSM-III diagnosis of attention deficit disorder with hyperactivity (ADD/H) based on structured diagnostic interviews of the child and mother and on two teacher and two parent rating scales. The degree of agreement between diagnostic classification of ADD/H based solely on criterion scores on each rating scale and classification based on the comprehensive clinical assessments that included use of the same rating scaleswas assessed by comparing the ratings of the 41 children with ADD/H to those of 47 clinic-referred children given other diagnoses or no diagnosis. The accuracy of classification was highly similar across scales. Increasing the cutoff score increased the acing true positives. Using the point of intersection of these two curves to choose the optimal cutoff scores resulted in 70–75% accurate classification and 25–30% misclassification of children given clinical diagnoses of ADD/H. This rate of misclassification suggests that rating scales alone should not be used to classify ADD/H for most clinical and research purposes, especially because the method of comparison used in this study favored finding a high degree of correspondence.  相似文献   
996.
Harm minimization approaches have been recommended to reduce the risks of transmission of HIV for injecting drug users by the elimination of sharing injecting equipment. The risks associated with the sexual behaviours of these individuals have been given less emphasis, and where considered have been in terms of the threat to non-drug partners and potential penetration of HIV infection into the general population. Data are presented from four survey studies conducted between 1985 and 1990 focusing on both drug-taking behaviours and sexual activities. These provide evidence for larger shifts, over this period, in injecting practices than in sexual behaviours. The risks associated with sexual activities for injecting drug users and their sexual partners are considered. It is concluded that counsellors have an important role to play in introducing a second phase of harm minimization that involves interventions to modify sexual behaviours and offers integrated services for injecting drug users and their families.  相似文献   
997.
In the first three experiments, we attempted to learn more about subjects' understanding of the importance of sample size by systematically changing aspects of the problems we gave to subjects. In a fourth study, understanding of the effects of sample size was tested as subjects went through a computerassisted training procedure that dealt with random sampling and the sampling distribution of the mean. Subjects used sample size information more appropriately for problems that were stated in terms of the accuracy of the sample average or the center of the sampling distribution than for problems stated in terms of the tails of the sampling distribution. Apparently, people understand that the means of larger samples are more likely to resemble the population mean but not the implications of this fact for the variability of the mean. The fourth experiment showed that although instruction about the sampling distribution of the mean led to better understanding of the effects of sample size, subjects were still unable to make correct inferences about the variability of the mean. The appreciation that people have for some aspects of the law of large numbers does not seem to result from an in-depth understanding of the relation between sample size and variability.  相似文献   
998.
Personality, social support, and psychological distress in later life   总被引:5,自引:0,他引:5  
A conceptual model was developed to address 2 issues that have received relatively little attention in the social support literature. First, an attempt was made to assess the interrelationships among 3 types or dimensions of supportive social relations. In addition, the impact of selected psychological and social factors on social support use was examined. Findings from a nationwide survey of older adults in the United Kingdom suggest that social contact tends to increase the amount of received support, and received support in turn tends to bolster perceptions of support availability in the future (i.e., anticipated support). With regard to the second issue, social roles (especially marital status) and social extraversion emerged as potentially important correlates of social support use in later life.  相似文献   
999.
This article reviews the essential features, types, prevalence, pathophysiology, and neuropsychological correlates associated with the sleep apnea syndrome. Persons who experience the intermittent hypoxia and fragmented sleep characteristic of the sleep apnea syndrome tend to exhibit moderate symptoms of diffuse cognitive dysfunction as well as multiple emotional and psychosocial sequela. It is concluded that more research is required in order to elucidate the relationship between the hypoxic parameters and neurocognitive deficits seen in the sleep apnea syndrome, and that neuropsychological assessment might represent a means whereby the effectiveness of various treatments for sleep apnea may be evaluated.  相似文献   
1000.
C Nelson  J Keith 《Adolescence》1990,25(97):183-204
This study contrasted female and male early adolescent sex role attitude and behavior development in an ecological context as defined by Bronfenbrenner. Data were the results of a state-wide survey of early adolescents and their parents. Hierarchical multiple regression was used to test both sex role attitude development and behavior development models. Only the models for attitude development were significant. The level of traditionalism of female sex role attitude development was significantly influenced by maternal employment, the level of traditionalism of the father's sex role attitudes in interaction with the amount of time he spent with his daughter, and chronological age. In contrast, the level of traditionalism of male sex role attitude development was significantly influenced by the level of traditionalism of the mother's sex role attitudes in interaction with the level of closeness to the mother that was reported by the son, and both mother's and father's perception of pubertal age. The implications of the findings for human development theory, early adolescence as a stage of development, and sex role theory and research 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