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   58776篇
  免费   2362篇
  国内免费   32篇
  2020年   678篇
  2019年   852篇
  2018年   1196篇
  2017年   1196篇
  2016年   1254篇
  2015年   854篇
  2014年   1088篇
  2013年   5253篇
  2012年   1862篇
  2011年   2059篇
  2010年   1186篇
  2009年   1246篇
  2008年   1842篇
  2007年   1858篇
  2006年   1640篇
  2005年   1472篇
  2004年   1454篇
  2003年   1329篇
  2002年   1394篇
  2001年   1858篇
  2000年   1739篇
  1999年   1348篇
  1998年   766篇
  1997年   702篇
  1996年   603篇
  1995年   596篇
  1994年   579篇
  1993年   617篇
  1992年   1110篇
  1991年   1022篇
  1990年   1016篇
  1989年   929篇
  1988年   881篇
  1987年   878篇
  1986年   876篇
  1985年   919篇
  1984年   747篇
  1983年   655篇
  1982年   561篇
  1980年   517篇
  1979年   725篇
  1978年   589篇
  1976年   531篇
  1975年   686篇
  1974年   705篇
  1973年   656篇
  1972年   591篇
  1971年   531篇
  1968年   577篇
  1967年   574篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
921.
922.
The present study was designed to explore both the predictors of ethnic identity and the relationship between ethnic identity and psychosocial adjustment. Perceptions of ethnicity and ethnic identity and measures of psychosocial adjustment were obtained from 82 Italian-Australian adolescents. Parents' maintenance of cultural ties was associated with a strong sense of ethnic identity, however ethnic identity was relatively unimportant in predicting psychosocial adjustment. Cultural variables such as parents' embeddedness in the Italian community, the desire to assimilate into the Australian culture, and the perception of problems arising from minority group membership were of greater significance.  相似文献   
923.
A cross-cultural study of psychological differentiation of Canadian and Pakistani high school students was undertaken to examine the nature of psychological differentiation in relation to differences in age/grade, gender, and academic programs. The study involved 707 Canadian students from grades 6, 8, 10, and 12; and 349 Pakistani students from grades 8, 9, 10, and 12. The Group Embedded Figures Test was employed as a measure of the field-dependence-independence cognitive style. Analyses of data included two-way and three-way analyses of variance to determine the effects of grade, gender, and academic program upon GEFT scores. Differences in psychological differentiation between high school students in the two cultures were discussed in terms of Berry's eco-cultural model.  相似文献   
924.
A new test for measuring the ability to perceive pictorial depth was used with children of two remote Bushman populations (!Xu and Kxoe), as well as with a sample of adult Bushmen drawn from these populations and a sample of urban Zulu children. The results show that subjects of apparently little sophistication are capable of perceiving depth when confronted with a ‘geometric’ figure. They also show surprising inter-group differences which cannot be easily explained by differences of environmental experience.  相似文献   
925.
The effects of the perceived accuracy of attributions of self blame and chance blame were examined in the context of health care. Health practitioners ( N = 147) rated interviews in which patients made self-or chance-blaming attributions for diseases with high (heart attack, stroke), or low (cancer, arthritis) life-style involvement, or acidental injuries. Three discriminant analyses yielded p < .001. Self-blaming heart and stroke patients were rated as coping better and acting more appropriately and typically than chance blamers. Other self blamers were rated as more depressed, poorly adjusted, coping poorly, not accepting disability, needing counselling and information. Additionally, self-blaming accident victims were judged as more dependent, less likeable, and having poorer prognoses than chance blamers. Realistic self blame for life-style diseases did not lead to victimization, but other self-blaming patients were stigmatized and the adaptiveness of self blame as a coping strategy was unrecognized.  相似文献   
926.
927.
Correlations between a job performance criterion and personality measures reflecting achievement motivation and an interpersonal orientation were examined at three points in time after completion of job training for a sample of airline reservations agents. Although correlations between the personality predictors and performance were small and nonsignificant for the 3-month period after beginning the job, by the end of 6 and 8 months a number of significant relationships had emerged. Implications for the utility of personality measures in selection and performance prediction are discussed.  相似文献   
928.
Because young children have poorer auditory temporal resolution than older children, they ought to have, according to the inverse relation between temporal and frequency resolution, narrower auditory filters than older children. Therefore, the auditory filters of two 6-year-olds, two 10-year-olds, and two adults were measured by having them detect a 400-ms sinusoid (500, 1000, or 3000 Hz) centered in a spectral notch in a band of noise. The signal power for 71% correct was determined as a function of notch width with the two-alternative, forced-choice procedure. The principal results showed a significant decrease in signal power with age and a significant interaction between age and notch width. The best-fitting parameters of a model of the auditory filter showed that the filter was significantly wider for the 6-year-olds than for the 10-year-olds or the adults.  相似文献   
929.
Pigeon's observational learning of successive visual discrimination was studied using within-subject comparisons of data from three experimental conditions. Two pairs of discriminative stimuli were used; each bird was exposed to two of the three experimental conditions, with different pairs of stimuli used in a given bird's two conditions. In one condition, observers were exposed to visual discriminative stimuli only. In a second condition, subjects were exposed to a randomly alternating sequence of two stimuli where the one that would subsequently be used as S+ was paired with the operation of the grain magazine. In a third experimental condition, subjects were exposed to the performance of a conspecific in the operant discrimination procedure. After exposures to conspecific performances, there was facilitation of discriminative learning, relative to that which followed exposures to stimulus and reinforcement sequences or exposures to stimulus sequences alone. Exposure to stimulus and food-delivery sequences enhanced performance relative to exposure to stimulus sequences alone. The differential effects of these three types of exposure were not attributable to order effects or to task difficulty; rather, they clearly were due to the type of exposure.  相似文献   
930.
The matching law applies to wagtails' foraging in the wild   总被引:2,自引:2,他引:0       下载免费PDF全文
Field data concerning the time budgets and foraging success of pied wagtails (Motacilla alba yarrelli, Gould) are reanalyzed. It is found that the data are well described by the generalized matching law, with a marked bias towards spending time on the territory. In this case matching is not the result of maximizing reward rate, but it remains possible that it results from an allocation of time that maximizes survival.  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