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   29314篇
  免费   1062篇
  国内免费   14篇
  2020年   301篇
  2019年   353篇
  2018年   458篇
  2017年   510篇
  2016年   541篇
  2015年   412篇
  2014年   457篇
  2013年   2255篇
  2012年   865篇
  2011年   888篇
  2010年   530篇
  2009年   567篇
  2008年   817篇
  2007年   755篇
  2006年   639篇
  2005年   619篇
  2004年   595篇
  2003年   599篇
  2002年   588篇
  2001年   725篇
  2000年   718篇
  1999年   509篇
  1998年   291篇
  1997年   273篇
  1992年   477篇
  1991年   461篇
  1990年   464篇
  1989年   466篇
  1988年   411篇
  1987年   429篇
  1986年   449篇
  1985年   491篇
  1984年   417篇
  1983年   385篇
  1982年   276篇
  1981年   320篇
  1979年   443篇
  1978年   320篇
  1977年   288篇
  1976年   276篇
  1975年   410篇
  1974年   463篇
  1973年   485篇
  1972年   410篇
  1971年   404篇
  1970年   380篇
  1969年   401篇
  1968年   494篇
  1967年   476篇
  1966年   453篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
801.
There have been major changes in English Law with regard to confession evidence, which followed the implementation of the Police and Criminal Evidence Act (PACE) in January 1986. This paper reviews the main legal changes that are relevant to the admissibility and reliability of confessions and their psychological importance within the context of both research and expert testimony.  相似文献   
802.
This article describes an important new area of research on services for children and adolescents with mental disorders at the National Institute of Mental Health, the parameters of mental health services research for youth, and the opportunities that are available for grant-funded investigations in this area.  相似文献   
803.
In a randomized clinical trial, multisystemic family preservation was shown to significantly reduce rates of criminal activity and incarceration in a sample of 84 serious juvenile offenders and their multi-need families. In the current study, archival records were searched for re-arrest an average of 2.4 years post-referral. Survival analysis showed that youths who received multisystemic family preservation were less likely to be re-arrested than were youths who had received usual services. Such results represent the first controlled demonstration that family preservation, when delivered via a clearly specified treatment model, has lasting effects with serious juvenile offenders. Implications for family preservation and juvenile justice research are discussed.  相似文献   
804.
To determine the frequency and correlates of nonsuicidal physically self-damaging acts in 12–14 year olds, a two stage epidemiologic survey with a self-administered questionnaire (N=3283) followed by a psychiatric interview of a subsample of the adolescents and their parents (N=444) was used. Prevalence estimates of interview validated nonsuicidal physically self-damaging acts were 2.46% in males and 2.79% in females. Significant relationships were found between nonsuicidal physically self-damaging acts and suicidal ideation, major depression and undesirable life events. Data suggest that physically self-damaging acts occur at substantial rates during early adolescence. The strong correlation between nonsuicidal self-destructive acts and both suicidal ideation and major depression clarifies prior conflicting reports in the literature and suggests that a history of self-damaging acts should be taken into consideration when evaluating for possible depression and suicide risk.  相似文献   
805.
Direct-observation procedures were used to objectively and efficiently assess several classes of service provided for individuals residing at two state facilities for the developmentally disabled. Time samples were taken of the condition of the clients' physical environment and of the clients themselves. The ongoing behavior of both clients and staff also was recorded. Each residence was observed at least three times during both regular work hours and evening/weekend hours. Results showed that both facilities scored high in the categories regarding the physical condition of the living areas, as well as the categories concerning the condition of the clients. Greater variability was seen in the data on client and staff behavior. More generally, the results indicate that time-sampling procedures can be used efficiently to collect data on multiple aspects of service delivery for large numbers of individuals.  相似文献   
806.
807.
The use of magnitude estimation as well as axiomatic measurement theory has led to the suggestion that loudness adds across critical bands. In the present paper, we challenge this postulate by applying a more sensitive methodology, based on Falmagne’s (1976) random conjoint measurement procedure. A necessary condition for additivity of loudness was investigated in tone complexes consisting of 2-kHz and 5-kHz (resp. 3-kHz) components; the results showed systematic deviations from additivity. We argue that these deviations are due to asymmetric masking of the higher component by the lower one, and we propose a tentative quantitative model to account for the data. Such a model is in line with results from tone-on-tone masking, which show masking to be effective over a range of several critical bands.  相似文献   
808.
The perception of continuously repeating auditory patterns by European starlings was explored in seven experiments. In Experiment 1, 4 starlings learned to discriminate between two continuously repeating, eight-element, auditory patterns. Each eight-element pattern was constructed from different temporal organizations of two elements differing in timbre. In Experiments 2–7, the repeating patterns were transformed in ways designed to identify the starlings’ perceptual organization of the patterns. In Experiment 2, the starlings identified patterns beginning with novel starting points. In Experiment 3, discrimination performance was adversely affected by reorganizing the elements in the patterns. In Experiments 4 and 5, the pattern elements were altered. In Experiment 4, the patterns were constructed from two novel elements. In Experiment 5, the temporal location of the two pattern elements was reversed. The transformations of the patterns in Experiments 4 and 5 affected discrimination performance for some, but not all, of the starlings. In Experiments 6 and 7, replacing either of the two elements with silent intervals had no effect on discrimination performance. The results of these experiments identify basic grouping principles that starlings use when they perceive auditory patterns.  相似文献   
809.
Sixteen German-English bilinguals were studied in a sleep laboratory for four nonconsecutive nights each. Half were native English speakers living in Zürich, and half native German speakers living in Atlanta. Presleep thought samples were solicited each evening and REM dream reports each night; subjects judged the waking appropriateness of their imagined speech and language phenomena, and also identified waking sources of their dream imagery, the following mornings. Incidences of dreaming and of speech therein generally were similar to those of monolinguals. Whether sessions were conducted in German (two nights) or English (two nights) did directly influence language selection in subjects' dreams. Judged appropriateness of language selection to imagined events was very high for thought samples, and high for REM dreams. Sources for thought samples were generally consonant with the language dominant at study site; for REM dreams this relationship was considerably weaker. Judged waking appropriateness to imagined situations was more strongly related to language selection than was the language reference of the supposed sources of those situations.  相似文献   
810.
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