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   28358篇
  免费   1023篇
  国内免费   9篇
  2019年   281篇
  2018年   451篇
  2017年   447篇
  2016年   456篇
  2015年   324篇
  2014年   402篇
  2013年   2059篇
  2012年   715篇
  2011年   741篇
  2010年   494篇
  2009年   476篇
  2008年   703篇
  2007年   649篇
  2006年   607篇
  2005年   532篇
  2004年   532篇
  2003年   519篇
  2002年   529篇
  2001年   749篇
  2000年   719篇
  1999年   572篇
  1998年   284篇
  1997年   304篇
  1996年   307篇
  1992年   541篇
  1991年   513篇
  1990年   493篇
  1989年   472篇
  1988年   494篇
  1987年   456篇
  1986年   494篇
  1985年   486篇
  1984年   431篇
  1983年   375篇
  1982年   297篇
  1981年   298篇
  1979年   452篇
  1978年   378篇
  1977年   328篇
  1976年   335篇
  1975年   400篇
  1974年   483篇
  1973年   515篇
  1972年   385篇
  1971年   418篇
  1970年   360篇
  1969年   398篇
  1968年   479篇
  1967年   450篇
  1966年   451篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Interpersonal loss and self-mutilation   总被引:1,自引:0,他引:1  
Self-mutilation was hypothesized to increase in frequency during periods of interpersonal loss in a treatment program for seriously disturbed adolescents. The study examined changes in the frequency of acts of self-mutilation, aggression, and running away for 32 teenagers who experienced interpersonal loss when staff members left employment. Data were collected for a 4-year period. Statistical findings indicated that the frequency of self-mutilation increased significantly during the time period of anticipated loss, 2 weeks prior to staff terminations. There was no significant increase in the frequency of self-mutilation immediately following the staff terminations. Also, there was no significant change in the rates of aggression or running away either before or after the loss events. It was concluded that the time of anticipated loss was the period of highest risk for these adolescents in terms of self-mutilative behavior.  相似文献   
982.
From Dialog's PsychINFO database the number of studies with 6 species reported in the Psychological Abstracts was calculated for each year from 1967 to 1988. Also, the number of studies with an additional 11 species were calculated for each year from 1973 to 1988. A hand search in the Journal of the Experimental Analysis of Behavior and Learning and Motivation was also conducted to explore trends in studies on 12 species from 1970 to 1987. The numbers of studies on many species (e.g., baboons, bats, chimpanzees, dolphins, gerbils, guinea pigs, gorillas, hamsters, lemurs, mice, pigeons, rats, seals, and snakes) have remained stable. There has, however, been a steady decline in the numbers of studies on selected species (e.g., cats, dogs, and rabbits). Possible reasons for changing trends in studies on selected species include: increased costs, the cognitive emphasis in psychology, and arguably, animal rights activism.  相似文献   
983.
A. W. Moore 《Erkenntnis》1997,46(1):5-32
Two of W. V. Quine's most familiar doctrines are his endorsement of the distinction between underdetermination and indeterminacy, and his rejection of the distinction between analytic and synthetic truths. The author argues that these two doctrines are incompatible. In terms wholly acceptable to Quine, and based on the underdetermination/indeterminacy distinction, the author draws an exhaustive and exclusive distinction between two kinds of true sentences, and then argues that this corresponds to the traditional analytic/synthetic distinction. In an appendix the author expands on one aspect of the underdetermination/indeterminacy distinction, as construed here, and discusses, in passing, some of Quine's more general views on truth.  相似文献   
984.
Guidance and counseling in the schools lack focus and direction. Some attribute this confusion within guidance and counseling to a lack of a philosophical foundation. Little is known about the philosophical assumptions of counselors functioning in secondary schools. In this study, the counselors in the secondary schools of Iowa identified most frequently with the phenomenological orientation. The experience of the counselors was related to their philosophical orientation. Counselors with less experience subscribed to an existential orientation.  相似文献   
985.
The face-to-face interactions of 43 polydrug-with-cocaine-using mothers and their infants at 3 and 6 months were compared to 17 non-cocaine-but other-drug-using mothers and 21 mothers who used no drugs during their pregnancy. Coders blind to mothers' drug use status scored 3 min of face-to-face interactions for 16 measures of maternal and infant interactive behaviors. A principal component of 7 behaviors formed a measure of maternal attentiveness; a principal component of 5 behaviors formed a measure of mother-infant dyadic organization; and a principal component of 4 behaviors formed a measure of infant readiness to interact. A measure of maternal interruption was computed as the mean standard score of 3 additional interruptive behaviors. At 3 and 6 months, polydrug-with-cocaine-using mothers were less attentive to interactions, and polydrug-with-cocaine-using mothers and their infants engaged in fewer dyadic interactions than either non-cocaine or non-drug-using mothers. Compared to 3 months, polydrug-with-cocaine-using mothers at 6 months were less attentive to interactions and more frequently interrupted interactions by looking away, redirecting the infant, or withdrawing, whereas non-cocaine-using and non-drug- using mothers showed no change or an improvement in attentiveness to interactions and a decrease in interruptions. No differences emerged in the interactive behaviors of the infants of polydrug- with-cocaine-using, non-cocaine-using, or non-drug-using mothers. Cocaine use represents a significant risk for diminished parental attentiveness and responsiveness to infants and for diminished interactiveness in infants.  相似文献   
986.
An adult, with a puppet held at shoulder height on either side (within the infant's visual field), interacted with 3- to-6-month-olds, turning her head intermittently to talk to a puppet. Seventy- three percent of infants' first eye-turns were in the direction of the adult head-turn.  相似文献   
987.
A Chinese advantage over Americans was found for economically relevant computational and reasoning abilities in arithmetic for groups of 6th- and 12th-grade students matched or equated on general intelligence. No cross-national difference for computational or reasoning abilities was found for samples of older (60- to 80-year-old) Chinese and American adults equated on general intelligence. The pattern of change in arithmetical competencies across cohorts suggests that the Chinese advantage in 6th and 12th grade is due to a cross-generational decline in competencies in the United States and a cross-generational improvement in China.  相似文献   
988.
Dienes and Berry (1997) argue that there really are two kinds of knowledge, implicit and explicit, that can be characterized through a subjective threshold. We argue that the subjective threshold does not separate two forms of knowledge, but instead two uses of knowledge, for two different purposes. With Neal and Hesketh (1997), we suggest that an understanding of learning will be better served by investigating the processing that occurs under various circumstances than by attempting to isolate learning that occurs with awareness from that which occurs without it.  相似文献   
989.
990.
Compositional semantics for a language of imperfect information   总被引:3,自引:0,他引:3  
  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