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   12375篇
  免费   547篇
  国内免费   3篇
  2020年   157篇
  2019年   159篇
  2018年   283篇
  2017年   252篇
  2016年   266篇
  2015年   192篇
  2014年   219篇
  2013年   959篇
  2012年   354篇
  2011年   405篇
  2010年   255篇
  2009年   219篇
  2008年   349篇
  2007年   341篇
  2006年   303篇
  2005年   250篇
  2004年   257篇
  2003年   237篇
  2002年   236篇
  2001年   430篇
  2000年   404篇
  1999年   292篇
  1998年   124篇
  1996年   114篇
  1993年   108篇
  1992年   233篇
  1991年   237篇
  1990年   225篇
  1989年   208篇
  1988年   222篇
  1987年   199篇
  1986年   189篇
  1985年   187篇
  1984年   178篇
  1983年   132篇
  1982年   138篇
  1979年   173篇
  1978年   116篇
  1977年   121篇
  1976年   114篇
  1975年   158篇
  1974年   171篇
  1973年   201篇
  1972年   165篇
  1971年   152篇
  1970年   136篇
  1969年   136篇
  1968年   187篇
  1967年   144篇
  1966年   151篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
One variable with which to evaluate scientific journals is how often their articles are cited in the literature. Such data are amenable to longitudinal analysis and can be used as a measure of a journal's impact on research within a discipline. We evaluated multiple citation measures for a number of applied journals in behavioral psychology from 1981 to 2000. The results indicate a relatively consistent impact across these journals, with some evidence of growth.  相似文献   
992.
The structure of self-reported symptoms representative of the tripartite model was examined using data drawn from the Medical Outcomes Study (Tarlov et al., 1989). Participants were persons who had been diagnosed 48 months previously as suffering from either depression (N = 315) or hypertension (N = 403). Results of confirmatory factor analyses were broadly consistent with the tripartite model (L. A. Clark & Watson, 1991). Factors emerged corresponding to each of the 3 posited first-order dimensions of negative affect, positive affect, and physiologic arousal. Nonetheless, some discrepancies were found between the observed data and the hypothesized tripartite model. First, the obtained physiologic arousal factor was best viewed as reflecting nonspecific somatic distress rather than physiologic arousal. Finally, although differentiable in the strictest statistical sense, all three domains were significantly correlated (.36 to.86, absolute value). In particular, contrary to the tripartite model, positive and negative affect covaried markedly (-.81 to -.86). Findings raise issues concerning the utility of the tripartite model as a heuristic framework for enhancing understanding of individual differences in normal mood as well as mood disorders.  相似文献   
993.
The purpose of this study was to determine whether the structure of children's self-concept, as rated by children themselves on the Self-Perception Profile for Children (SPPC; Harter, 1985), and the structure of children's competence, as rated by their parents on the Rating Scale of Child's Actual Behavior (PRS) and teachers on the Rating Scale of Child's Actual Behavior (TRS; Harter, 1985), are similar across samples of children with and without spina bifida (children were 8 and 9 years of age; n = 68 in each sample). Using confirmatory factor analyses, results revealed that a multidimensional model for the SPPC and the TRS fit the data well for both samples. On the other hand, the model for both mothers' and fathers' PRS ratings did not fit the data for the spina bifida sample. Further tests of factorial invariance conducted on the SPPC and TRS revealed that the spina bifida and able-bodied samples tended to have the same pattern and magnitude of factor loadings for both instruments. There was some invariance, however, in the amount of unique error variance accounted for across samples. These results bolster our confidence in using the SPPC and TRS to compare children with and without spina bifida.  相似文献   
994.
In a speeded choice reaction time task, responses to centrally presented letter targets can be altered by the identity of surrounding task-irrelevant letters (flankers). In the standard flanker effect, flankers associated with the same response as the target lead to faster and more accurate responses, whereas flankers associated with a different response lead to slower and more error-prone responses. B. A. Eriksen and C. W. Eriksen (1974, pp. 143-149) have argued that these flanker effects occur through response competition. We present data from a novel version of the Eriksen task, in which some targets and flankers consist of letter forms that are morphed versions of target letters. In this paradigm, flankers induce classic flanker effects on well-formed targets. But flankers induce an opposite effect, termed a negative flanker effect on morphed letter targets. For example, targets that are morphs between the letters "A" and "H" are more likely to be identified as an "A" when flanked by an "H." The interpretation advanced here is that there are two distinct kinds of flanker effects contrast enhancement in perceptual processes and response competition in response selection processes.  相似文献   
995.
996.
This study is an empirical investigation of how 175 university students obtained their knowledge of sexual matters and whether pornography functioned as an important source. Analysis indicated that pornography does not play an important role in the dissemination of sexual information; peers appear to be the primary source. There are, however, certain statistically significant differences between the sexes in reports of the extent of specific sexual information from pornography on matters such as oral and anal intercourse. The findings extend research on pornography as a source of sex information and are contrasted with previous studies.  相似文献   
997.
Let each of several (generally interdependent) random vectors, taken separately, be influenced by a particular set of external factors. Under what kind of the joint dependence of these vectors on the union of these factor sets can one say that each vector is selectively influenced by “its own” factor set? The answer proposed and elaborated in this paper is: One can say this if and only if one can find a factor-independent random vector given whose value the vectors in question are conditionally independent, with their conditional distributions selectively influenced by the corresponding factor sets. Equivalently, the random vectors should be representable as deterministic functions of “their” factor sets and of some mutually independent and factor-independent random variables, some of which may be shared by several of the functions.  相似文献   
998.
Children's working-memory processes: a response-timing analysis   总被引:3,自引:0,他引:3  
Recall response durations were used to clarify processing in working-memory tasks. Experiment 1 examined children's performance in reading span, a task in which sentences were processed and the final word of each sentence was retained for subsequent recall. Experiment 2 examined the development of listening-, counting-, and digit-span task performance. Responses were much longer in the reading-and listening-span tasks than in the other span tasks, suggesting that participants in sentence-based span tasks take time to retrieve the semantic or linguistic structure as cues to recall of the sentence-final words. Response durations in working-memory tasks helped to predict academic skill and achievement, largely separate from the contributions of the memory spans themselves. Response durations thus are important in the interpretation of span task performance.  相似文献   
999.
This article reports 2 studies investigating the effects of retrospective thought on future cooperation in social dilemmas. Some general theories of cooperation presume, but have not tested, whether retrospection has impact: People may think about the choices they could have made instead, realize that cooperation would have produced larger outcomes, and change their strategy as a result. Across both studies, the authors show that rate of future cooperation is directly related to the number of best-case scenarios and inversely related to the number of worst-case scenarios generated. The 2nd study also shows that the number and type of retrospective thoughts generated can be predicted from the person's social value orientation.  相似文献   
1000.
Although at the time of this article's publication, many anecdotes and cross-sectional studies had reported that law students experience significant distress during their 1st year, few researchers had controlled for prelaw school status (e.g., M. Garrison, B. Tomko, & I. Yip, 1996; L. Guinier, M. Fine, J. Balin, A. Bartow, & D. L. Stachel, 1994), and only a single group of researchers had explored a psychosocial factor that predicted these changes. The present authors tested 3 sets of potential predictors of adjustment: sources of stress, coping strategies, and relationship factors. The present data replicated declines in students' psychological health, physical health, and attitudes toward law over the 1st year of school. That result supports the generalizability and currency of previous studies. In contrast to other researchers, the present authors found few gender differences. Less relationship happiness, less emotional support, and use of less active coping tactics at the beginning of the year predicted poorer outcomes at the end of the year. Strain from academic pressures, lack of personal time, and social isolation were correlated with poorer outcomes.  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