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   35792篇
  免费   1508篇
  国内免费   8篇
  2020年   398篇
  2019年   508篇
  2018年   714篇
  2017年   735篇
  2016年   751篇
  2015年   539篇
  2014年   679篇
  2013年   2805篇
  2012年   1138篇
  2011年   1203篇
  2010年   701篇
  2009年   718篇
  2008年   1035篇
  2007年   1020篇
  2006年   934篇
  2005年   827篇
  2004年   817篇
  2003年   754篇
  2002年   755篇
  2001年   1057篇
  2000年   994篇
  1999年   750篇
  1998年   406篇
  1997年   332篇
  1996年   327篇
  1992年   564篇
  1991年   557篇
  1990年   540篇
  1989年   549篇
  1988年   536篇
  1987年   505篇
  1986年   527篇
  1985年   572篇
  1984年   464篇
  1983年   441篇
  1982年   368篇
  1981年   344篇
  1979年   534篇
  1978年   386篇
  1976年   363篇
  1975年   442篇
  1974年   495篇
  1973年   513篇
  1972年   418篇
  1971年   394篇
  1970年   392篇
  1969年   416篇
  1968年   494篇
  1967年   431篇
  1966年   429篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
Suicides among older adults in the United States and Canada in the last decade have accounted for an increasing share of all suicides. In both countries the use of firearms among older adults has steadily increased. Despite these trends, little is known about the extent to which crisis centers are prepared to prevent elder suicide. A survey of AAS-listed crisis prevention centers examined the training, knowledge, and current practices relevant to elder suicide among personnel in 321 crisis prevention centers in both countries. Results revealed insufficient training, a lack of familiarity with recent suicide trends, and limited outreach to older adults.  相似文献   
42.
The country‐of‐origin effect is a topic central to the field of international marketing. Country of origin has been found to exert a particularly potent effect on consumer evaluation in situations where there is a strong link between a country and a particular product category. The present study provides further insight into how this particular effect can be understood. Drawing on a novel conceptualization of how country image and product categories interact, this study tested the relative evaluative relevance of product category with respect to estimates of brand equity across a variety of product categories. The findings suggest that facets of a country's image that are more closely related to the evaluation situation exert a greater influence on the evaluation of brands. This result encourages scholars as well as practitioners to re‐evaluate which situations might cause the country of origin effect to hold managerial relevance and paves the way for new paths toward a more comprehensive understanding of the effect. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
43.
44.
45.
46.
A series of stereograms are presented which demonstrate that texture boundaries can strongly influence the perception of discontinuities between neighbouring three-dimensional (3-D) surfaces portrayed by means of stereo cues. In these demonstration figures, no stereo information is available in the immediate vicinity of the boundary between the two 3-D stereo surfaces because all texture in that region is removed in one eye's view. On the other hand, various forms of texture boundary information are provided in the resulting monocular region. This stimulus paradigm is used to explore the question: what influence does texture boundary information have on the nature of the perceived 3-D surface that is interpolated between two stimulus regions which carry stereo cues? It is shown that if a clear-cut texture boundary is present in the monocular region then this is used by the human visual system to fix the perceived location of 3-D crease and step surface discontinuities between the stereo regions. Collett (1985) explored this issue with a similar methodology and reported weak and unreliable assistance from monocular texture boundaries in helping shape 3-D stereo surface discontinuities. The strong and robust phenomena demonstrated here seem to rely on two main differences between the present stimuli and those of Collett. In the present stimuli, figurally continuous textures containing strong texture boundaries are used, together with a technique for minimising the complications, including binocular rivalry, that arise from the borders of the stimulus regions present in only one half of each stereogram.  相似文献   
47.
48.
49.
50.
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