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   4863篇
  免费   460篇
  国内免费   273篇
  2024年   15篇
  2023年   143篇
  2022年   65篇
  2021年   127篇
  2020年   211篇
  2019年   281篇
  2018年   219篇
  2017年   269篇
  2016年   234篇
  2015年   202篇
  2014年   214篇
  2013年   951篇
  2012年   131篇
  2011年   197篇
  2010年   145篇
  2009年   220篇
  2008年   244篇
  2007年   210篇
  2006年   221篇
  2005年   198篇
  2004年   173篇
  2003年   156篇
  2002年   136篇
  2001年   97篇
  2000年   82篇
  1999年   61篇
  1998年   67篇
  1997年   53篇
  1996年   55篇
  1995年   42篇
  1994年   43篇
  1993年   20篇
  1992年   25篇
  1991年   10篇
  1990年   5篇
  1989年   10篇
  1988年   2篇
  1987年   5篇
  1985年   9篇
  1984年   9篇
  1983年   5篇
  1982年   5篇
  1981年   4篇
  1980年   5篇
  1979年   3篇
  1978年   4篇
  1977年   6篇
  1976年   3篇
  1975年   2篇
  1973年   1篇
排序方式: 共有5596条查询结果,搜索用时 15 毫秒
31.
Culture wars: American moral divisions across the adult lifespan   总被引:1,自引:0,他引:1  
Sociologists have argued that the public moral debate in contemporary America is characterized by a “culture war,” pitting “orthodox” and “progressivist” groups against one another (Hunter, 1991). This study addressed whether the culture war is evident in the moral thinking of ordinary Americans, and whether age-related patterns exist. Sixty fundamentalist Baptists (orthodox) and 60 mainline Baptists (progressivist) evaluated and reasoned about moral issues such as divorce and abortion. Each group was divided evenly into three age groups copsisting of young, midlife, and older adults. Moral reasoning was analyzed in terms of Shweder's (1990) ethics of autonomy, community, and divinity. Within all three age groups, progressivists used the ethic of, autonomy more than orthodox participants. Orthodox participants used the ethic of divinity more than progressivists. Orthodox and progressivist groups did not differ much in their use of the ethic, of community. Very few age group differences were found within the orthodox and progressivist groups. It is concluded that morality is conceived of in markedly different wasy by orthodox and progressivist groups, and that these conceptions are consistent across age groups.  相似文献   
32.
This paper describes the basic elements of practice development and management within the academic medical setting. These include assessment of the market environment, both in the community and within the medical setting, product development, marketing, budget basics, quality, managed care negotiations, and finding time to do research in a financially-driven health care system.  相似文献   
33.
Relation algebras from cylindric and polyadic algebras   总被引:1,自引:0,他引:1  
  相似文献   
34.
35.
本文对1—5岁汉族儿童使用双宾结构的状况进行了考察。首先对儿童语言中双宾结构的结构类型、句法功能及其发展状况进行了描述分析;在此基础上,讨论了儿童习得汉语双宾结构的机制。  相似文献   
36.
婴儿共同注意能力的发展   总被引:5,自引:0,他引:5  
董奇  曾琦 《心理科学》1997,20(4):298-302
本研究采用严格的实验室测验法,从年龄趋势、学习能力、性别差异三方面考察了8~11个月婴儿共同注意能力的发展。结果表明:1)婴儿的共同注意力在8~11个月间逐步提高,9个月左右出现显著的发展性变化,但1岁以前,该能力的发展水平都较低;2)就共同注意而言,婴儿具有从练习经验中学习的可能性,且学习能力存在年龄差异,8个月的婴儿基本不能从练习中受益,而8个月以上的其他三组婴儿在练习后共同注意水平都有不同程度的提高;3)总体而言,女婴共同注意能力的发展水平显著地高于男婴。  相似文献   
37.
Pigeons were trained on a pair-comparison task in which left versus right choices were reinforced following different sequences of two center-key stimuli. Choice accuracy was higher when retention intervals occurred after the entire sequence than when they separated the two stimuli comprising it, and this effect occurred independently of whether the initial and terminal stimuli came from the same or different dimensions. The initial stimulus from the prior trial was a source of proactive interference only in groups for which the retention interval separated the two sequence stimuli. By contrast, differential delay-interval behavior was observed only in groups for which the retention interval followed presentation of the entire sequence. These results indicate that coding processes in delayed discriminations are influenced by the location of the retention interval, and that response mediation affects retention performances if the reinforced choice can be determined prior to the interval.  相似文献   
38.
The standard Pawlak approach to rough set theory, as an approximation space consisting of a universe U and an equivalence (indiscernibility) relation R U x U, can be equivalently described by the induced preclusivity ("discernibility") relation U x U \ R, which is irreflexive and symmetric.We generalize the notion of approximation space as a pair consisting of a universe U and a discernibility or preclusivity (irreflexive and symmetric) relation, not necessarily induced from an equivalence relation. In this case the "elementary" sets are not mutually disjoint, but all the theory of generalized rough sets can be developed in analogy with the standard Pawlak approach. On the power set of the universe, the algebraic structure of the quasi fuzzy-intuitionistic "classical" (BZ) lattice is introduced and the sets of all "closed" and of all "open" definable sets with the associated complete (in general nondistributive) ortholattice structures are singled out.The rough approximation of any fixed subset of the universe is the pair consisting of the best "open" approximation from the bottom and the best "closed" approximation from the top. The properties of this generalized rough approximation mapping are studied in the context of quasi-BZ lattice structures of "closed-open" ordered pairs (the "algebraic logic" of generalized rough set theory), comparing the results with the standard Pawlak approach. A particular weak form of rough representation is also studied.  相似文献   
39.
The present study describes the diagnostic profile of over 800 adolescents admitted to residential therapeutic community programs for treatment of drug abuse and related problems. The relationship between race/ethnicity and psychiatric disturbance is examined, and the association among these factors to outcome is investigated. Over 90% of the sample had a DSM-III-R nonsubstance diagnosis. There were significant differences among the race/ethnic groups on attention deficit-hyperactivity and the disruptive behavior and affective disorders. In general, African-American adolescents yielded the lowest rates of disturbance across all categories of disorders. There was no relationship among race/ethnicity, psychiatric disturbance, and 1-year posttreatment outcomes.  相似文献   
40.
Coping—competence theory yields a structural model of the development of persistent aggression in which current challenge encounters determine future life outcomes and competence. Driven by this model, universal, school-based prevention programs would aim in multiple ways to promote prosocial coping among high-risk, resilient, and advantaged youth from kindergarten through high school. Expected benefits of prosocial coping would include: less aggressive behavior, fewer adverse life outcomes (e.g., school dropout, police arrest, teen pregnancy, conduct, mood, and substance-use disorders), and a more competent self-definition and social reputation. Five stages are described that may prove useful in creating prosocial schools and neighborhoods supportive of youth in transition away from antisocial coping and deviant peers.  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