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   26836篇
  免费   982篇
  国内免费   10篇
  2018年   381篇
  2017年   417篇
  2016年   447篇
  2015年   302篇
  2014年   390篇
  2013年   1972篇
  2012年   678篇
  2011年   740篇
  2010年   498篇
  2009年   458篇
  2008年   725篇
  2007年   662篇
  2006年   646篇
  2005年   545篇
  2004年   545篇
  2003年   560篇
  2002年   562篇
  2001年   673篇
  2000年   674篇
  1999年   526篇
  1998年   288篇
  1997年   305篇
  1996年   303篇
  1995年   280篇
  1992年   503篇
  1991年   468篇
  1990年   459篇
  1989年   439篇
  1988年   463篇
  1987年   421篇
  1986年   461篇
  1985年   447篇
  1984年   403篇
  1983年   342篇
  1982年   267篇
  1981年   280篇
  1979年   415篇
  1978年   335篇
  1977年   295篇
  1976年   313篇
  1975年   347篇
  1974年   441篇
  1973年   473篇
  1972年   344篇
  1971年   369篇
  1970年   335篇
  1969年   361篇
  1968年   437篇
  1967年   399篇
  1966年   415篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
It has been established through several decades of research that children's home environments significantly influence their development. Many researchers have also been interested in expanding research beyond indirect measures of the home environment, such as socioeconomic status, to help understand the nature of specific environmental mechanisms which influence early behavior and cognitive development. The Home Observation for Measurement of the Environment (HOME) Inventory was developed to meet these needs. Specifically, HOME measures the quality of stimulation in a child's early family environment. Almost all studies of the approach's reliability and validity have been conducted with US samples. HOME is, however, being used in other countries. The authors report their findings from a study of whether the psychometric properties of HOME based upon US samples parallel those found in Costa Rica, and whether HOME discriminates between Costa Rican environments with different associations to child health and development. Focus centers upon the infant/toddler version of the HOME Inventory. HOME data for 183 healthy Costa Rican infants were compared to the original HOME standardization sample from Little Rock, Arkansas. The study found the HOME Inventory to be helpful in identifying children at risk for delayed development in this Latin American sample. Lower HOME scores related to a shorter duration of breastfeeding and differentiated children with iron deficiency anemia in infancy, a condition associated with long-lasting developmental disadvantage.  相似文献   
992.
993.
On Bohm's formulation of quantum mechanics particles always have determinate positions and follow continuous trajectories. Bohm's theory, however, requires a postulate that says that particles are initially distributed in a special way: particles are randomly distributed so that the probability of their positions being represented by a point in any regionR in configuration space is equal to the square of the wave-function integrated overR. If the distribution postulate were false, then the theory would generally fail to make the right statistical predictions. Further, if it were false, then there would at least in principle be situations where a particle would approach an eigenstate of having one position but in fact always be somewhere very different. Indeed, we will see how this might happen even if the distribution postulate were true. This will help to show how loose the connection is between the wave-function and the positions of particles in Bohm's theory and what the precise role of the distribution postulate is. Finally, we will briefly consider two attempts to formulate a version of Bohm's theory without the distribution postulate.  相似文献   
994.
This study investigates gender similarity in the effects of birth order upon political leadership. Town supervisors were the leaders studied as there are a considerable number of women who attain this level of leadership. Questionnaires about birth order and family size were gained from 66 women who were town supervisors in New York State in 1992, and compared to a randomly selected sample of 57 male town supervisors. It was found that women as well as men town supervisors were more likely to have been first born in their families. However, whereas gender does not apparently influence the relevance of birth order for leadership, it clearly does exert an influence on the level of political leadership attained. Women town supervisors gained their positions in towns that were considerably smaller than the towns led by the male supervisors. Discussion concerned the nature of family experiences that contribute to leadership training, including those that may be different for girls and boys. Further research is needed to clarify barriers to female assertion of political leadership at more senior levels, because as this study shows, female leadership is being trained in families.  相似文献   
995.
Book reviews     
Science as Salvation: a Modern Myth and its Meaning, Mary Midgley, 1994. London, Routledge x +256pp., Hb 04 15062713, £35; Pb 04 15107733, £8.99

Philosophical Naturalism, David Papineau, 1993 Oxford, Basil Blackwell xii +219pp., Hb 0631189025, £40; Pb 0631189033, £14.99

F. H. Bradley, Writings on Logic and Metaphysics, James W. Allard & Guy Stock (Eds), 1994. Oxford, Clarendon Press xv+357pp, Hb 0–198–24445–2, £40.00; Pb 0–198–24438‐X, £14.95

Invariance and Heuristics: Essays in Honour of Heinz Post, Steven French & Harmke Kamminga (Eds), 1993 Boston Studies in the Philosophy of Science, Vol. 148 Kluwer Academic Publishers, Dordrecht

Beyond Reason: Essays on the Philosophy of Paul Feyerabend, GONZALO MUNÉVAR (Ed.), 1991. Dordrecht, Kluwer Academic Publishers xxi + 535pp., hb, ISBN 0–7923–1272–4, £104.20

World Changes: Thomas Kuhn and the Nature of Science, Paul Horwich (Ed.), 1993. Cambridge, MA, Bradford Books/MIT Press vi + 356pp., pb, ISBN 0262581388, £14.95

Realism Rescued: How Scientific Progress is Possible, Jerold L. Aronson, Rom Harré & Eileen Cornell Way, 1994 London, Duckworth vii +213pp., Hb 0715624768, £30.00

Scientific Nihilism: On the Loss and Recovery of Physical Explanation, Daniel Athearn, 1994. State University of New York Press, Albany ix + 387pp., Hb ISBN 0–7914–1807–3, £52

Theism, Atheism, and Big Bang Cosmology, William Lane Craig & Quentin Smith, 1993. Oxford, Clarendon Press x +342pp., Hb 0198263481, £35; Pb 019826383X, £13.95  相似文献   

996.
997.
Factor analysis of 18 Likert-type items dealing with gender stereotypes about family roles was conducted and yielded two measures: one focused on marital roles and one focussed on child rearing. Respondents were parents of children in the third and fourth grades of a large industrialized city in the Midwest. The sample included 364 families equally divided between middle and lower class with 23% African American and 77% European American. For both scales, more stereotyped scores were obtained by parents who were lower in social status, less educated, full-time homemakers, African Americans, and fathers. Parents' scores related to a separate measure of children's stereotypes and the marital-role attitudes related to actual roles reported by family members. Daughters whose parents obtained less stereotyped scores had a more internal locus of control, showed a trend toward more independent coping skills, and—in the middle class—obtained higher scores on achievement tests.This research was supported by Grant No. 91-1437-91 from the William T. Grant Foundation.  相似文献   
998.
999.
Causal attributions (i.e., locus, stability, globality) and responsibility attributions (i.e., bad intent, selfish motivation, blame) were assessed in the spouses of 27 depressed psychiatric inpatients and 30 nondepressed dyads to test predictions derived from Hooley's (1987) symptom-controllability model of marital distress. Results indicated that (1) depressed patients and their spouses were less dyadically adjusted than nondepressed spouses, (2) causal and responsibility attributions about depressive behaviors predicted lower dyadic adjustment, and (3) attributions of causality mediated the relationship between group status (depressed or nondepressed) and dyadic adjustment among spouses who had higher expectations for their partner to change. Results suggest that among spouses with a high expectancy for change, depression may be a risk factor for marital distress.  相似文献   
1000.
DSM-based research on comorbidity has suggested thatdepression andpersonality disorder frequently occur together and that the combination of syndromes is associated with a poor response to treatment for depression. The present study was designed to explore the effect of comorbid Axis II pathology for a sample of 45 inpatients who received treatment for major depression. Both categorical and dimensional ratings of personality disorder were used in the statistical analysis. Positive categorical diagnosis of Cluster C (anxious-avoidant) disorder, as well as higher dimensional rating of Cluster A (odd-eccentric) pathology, was predictive of a poor response to treatment (p<.05), as measured by change in pre-post clinical ratings on the Montgomery-Asberg Depression Rating Scale. These results were construed as indicative of a significant Axis II comorbidity effect in the context of an inpatient, multimodal treatment setting for depression. The results also spotlight the influence of techniques of measurement in determining the outcome of statistical analysis.  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