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   9633篇
  免费   353篇
  国内免费   2篇
  2020年   135篇
  2019年   138篇
  2018年   214篇
  2017年   197篇
  2016年   195篇
  2015年   143篇
  2014年   185篇
  2013年   908篇
  2012年   288篇
  2011年   318篇
  2010年   195篇
  2009年   234篇
  2008年   247篇
  2007年   292篇
  2006年   233篇
  2005年   230篇
  2004年   229篇
  2003年   212篇
  2002年   233篇
  2001年   209篇
  2000年   158篇
  1999年   150篇
  1998年   125篇
  1997年   141篇
  1996年   120篇
  1995年   109篇
  1994年   110篇
  1993年   143篇
  1992年   151篇
  1991年   138篇
  1990年   124篇
  1989年   128篇
  1988年   130篇
  1987年   135篇
  1986年   113篇
  1985年   119篇
  1984年   137篇
  1983年   126篇
  1982年   140篇
  1981年   119篇
  1980年   122篇
  1979年   134篇
  1978年   159篇
  1977年   142篇
  1976年   127篇
  1975年   170篇
  1974年   143篇
  1973年   115篇
  1972年   103篇
  1971年   109篇
排序方式: 共有9988条查询结果,搜索用时 15 毫秒
261.
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   
262.
In English, counting-out rhymes, such as “Eenie Meenie,” vary little over retellings. Recall is not rote but is sensitive to the structure of the genre. To test the generality of this finding, a sample of Romanian rhymes was collected. Although there was no overlap with the English rhymes, the corpus of rhymes collected had similar structure in terms of number of lines, repeating words, rhyme, alliteration, and the inclusion of nonsense words. Variation within rhymes preserved the poetic structure of the genre. The results suggest that verbatim recall can be schema driven if there is sufficient structure.  相似文献   
263.
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   
264.
Although many researchers wishing to use the World-Wide Web for academic purposes rely on centralized Web services, they should be aware that it is neither expensive nor difficult to operate their own server. Doing so provides research-related benefits such as complete control over their host name and documents provided, the guaranteed ability to execute common gateway interface and server-side include programs, immediate access to their collected data, and the ability to better control who participates in their experiments. This paper surveys Web-server software features likely to be of interest to psychologists and conceptually summarizes their operation and use. The basic steps required to set up a Web server on popular microcomputers are reviewed, and security issues concerning Web-server operation are discussed. An accompanying resource Web page can assist users in setting up their own servers.  相似文献   
265.
266.
Recent studies suggest that performance attendant on visual word perception is affected not only by feedforward inconsistency (i.e., multiple ways to pronounce a spelling) but also by feedback inconsistency (i.e., multiple ways to spell a pronunciation). In the present study, we provide a statistical analysis of these types of inconsistency for all monosyllabic English words. This database can be used as a tool for controlling, selecting, and constructing stimulus materials for psycholinguistic and neuropsychological research. Such large-scale statistical analyses are necessary devices for developing metrics of inconsistency, for generating hypotheses for psycholinguistic experiments, and for building models of word perception, speech perception, and spelling.  相似文献   
267.
Nonparametric regression techniques, which estimate functions directly from noisy data rather than relying on specific parametric models, now play a central role in statistical analysis. We can improve the efficiency and other aspects of a nonparametric curve estimate by using prior knowledge about general features of the curve in the smoothing process. Spline smoothing is extended in this paper to express this prior knowledge in the form of a linear differential operator that annihilates a specified parametric model for the data. Roughness in the fitted function is defined in terms of the integrated square of this operator applied to the fitted function. A fastO(n) algorithm is outlined for this smart smoothing process. Illustrations are provided of where this technique proves useful.  相似文献   
268.
This study evaluates the behavioral consequences of childhood abuse (sexual, physical, or both), with particular focus on prevalence of posttraumatic stress disorder (PTSD). Three abuse type groups and nonabused controls were contrasted on behavioral rating scales and on structured psychiatric interview data. The participants (109 abused children and 16 normal control children) were recruited from Arkansas Children’s Hospital and local agencies for abused children. As expected, proportionately more females than males were sexually abused. Overall, males were rated as more disturbed than females. Type of abuse did not consistently influence behavioral ratings. Externalizing scores were significantly higher than internalizing scores in all abused groups. PTSD was diagnosed in 50% of the abused children, with a higher rate for boys who had been sexually abused as opposed to physically abused only (58% versus 13%). The most frequent comorbid condition with PTSD was Separation Anxiety. Sexually abused boys were hospitalized for psychiatric treatment at a higher rate than were other abused children.  相似文献   
269.
In this paper, we examine whether color and shape, tied to a single object in space, (1) are identified and selected in series or in parallel, (2) are identified and selected in a dependent, self-terminating manner or in an independent and exhaustive manner, and (3) are conjoined by a feature integration process before or only after an initial stage of separate attribute analyses has finished. We measured response time and the selection negativity (SN) derived from event-related brain potentials when participants responded to a unique conjunction of color and shape in a go/no-go target detection task. The discriminability of the color and the shape of the conjunction was manipulated in three conditions. When color and shape were easy to discriminate, the SNs to color and shape started at the same time. When one attribute was less discriminable, the SN to that attribute started later, but not the SN to the complementary attribute. This suggests that color and shape are identified and selected in parallel. In all three discriminability conditions, the SNs to color and shape were initially independent but later interacted. This suggests that color and shape are initially selected independently and exhaustively, after which their conjunction is analyzed. The SN to local shape features started later than that to the conjunction of color and global shape features, which suggests that feature integration can start before the analyses of the separate attributes have finished.  相似文献   
270.
We argue that negotiators' fixed-sum perceptions are caused by the same judgment process that creates false consensus. Bargainers' reliance on their own preferences as a cue to others' preferences leads them to anticipate a fixed-sum conflict. When presented with stereotypic cues, subjects in a negotiating experiment anticipated the variable-sum nature of the task and subsequently realized highly efficient settlements extremely quickly. Surprisingly, even when the party's preferences were unrepresentative of the stereotype, agreements were no less efficient than in the absence of the cue. The implications of these findings for bargaining research and practice 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