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   176419篇
  免费   7851篇
  国内免费   155篇
  2021年   1510篇
  2020年   2824篇
  2019年   3481篇
  2018年   3574篇
  2017年   4030篇
  2016年   4684篇
  2015年   3970篇
  2014年   4838篇
  2013年   23611篇
  2012年   4634篇
  2011年   3871篇
  2010年   4004篇
  2009年   4859篇
  2008年   4065篇
  2007年   3592篇
  2006年   4154篇
  2005年   4107篇
  2004年   3588篇
  2003年   3267篇
  2002年   3033篇
  2001年   3547篇
  2000年   3397篇
  1999年   3310篇
  1998年   2883篇
  1997年   2695篇
  1996年   2590篇
  1995年   2432篇
  1994年   2406篇
  1993年   2351篇
  1992年   2716篇
  1991年   2559篇
  1990年   2407篇
  1989年   2300篇
  1988年   2263篇
  1987年   2291篇
  1986年   2253篇
  1985年   2497篇
  1984年   2561篇
  1983年   2320篇
  1982年   2393篇
  1981年   2359篇
  1980年   2187篇
  1979年   2211篇
  1978年   2205篇
  1977年   2177篇
  1976年   1951篇
  1975年   2019篇
  1974年   2074篇
  1973年   1951篇
  1972年   1545篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
151.
In two experiments, hungry rats were given instrumental lever-press training for an appetitive reinforcer and, in addition, were exposed to another type of food which was not contingent on lever pressing. In the first experiment, exposure to each type of food was on separate days, whereas in the second experiment rats were exposed to each type of food in strict alternation within each session. Subsequently, a food aversion was conditioned to the reinforcer for the experimental group and to the non-contingent food for the control group. In both experiments, animals with an aversion to the reinforcer responded less in an extinction test than animals with an aversion to the non-contingent food. Subsequent reacquisition tests confirmed that the aversion to the non-contingent food in the control group was of comparable strength with that to the reinforcer in the experimental group. The results were discussed in terms of whether the reinforcer is encoded in the associative structure set up by exposure to an instrumental contingency.  相似文献   
152.
Early explications of family communication patterns (FCP) suggested that a family's communication pattern arises as a result of interactions in which parents and adolescents influence each other. In contrast, empirical research usually treats FCP as parent‐imposed norms that influence socialization outcomes in adolescents, without testing whether adolescents' socialization influences FCP. This study revisits the assumption that adolescents influence FCP, using data from a longitudinal quasi‐experimental evaluation of a school‐based civics curriculum intervention (N = 313 parent‐adolescent pairs). Results show that the intervention‐stimulated adolescents to initiate discussion of politics at home and that these adolescent‐initiated discussions influenced adolescents' and parents' perceptions of FCP 6 months later.  相似文献   
153.
The essay examines intellectual virtue in the Summa theologiae, taking it as an interpretative key to the epistemology of the Summa theologiae as a whole. Because Aquinas blurs the line between the acquired and the theological virtues, and between virtues and the gifts of the Spirit, it becomes impossible to maintain the distinction between the realms of nature and grace, or between natural reason and revealed truth: grace permeates the most ordinary activities of human reasoning. This reading of the Summa theologiae raises questions about many contemporary debates, particularly those concerning natural law.  相似文献   
154.
155.
156.
157.
158.
159.
160.
Gay marriages (as such) are not as yet allowed anywhere but the demand for them is increasing. Most countries take a liberal attitude towards marriage: few obstacles are put in its way. But objections to gay marriages continue to be raised. These objections are refuted and the case for gay marriage is assessed through the prism of various forms of liberalism. The normative argument for allowing gay marriage is shown to be both strong and consistent with many of the values upheld by the opponents of such unions.  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