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   173099篇
  免费   7812篇
  国内免费   156篇
  2021年   1486篇
  2020年   2761篇
  2019年   3417篇
  2018年   3503篇
  2017年   3954篇
  2016年   4583篇
  2015年   3902篇
  2014年   4779篇
  2013年   23367篇
  2012年   4545篇
  2011年   3702篇
  2010年   3868篇
  2009年   4750篇
  2008年   3850篇
  2007年   3416篇
  2006年   4046篇
  2005年   4019篇
  2004年   3529篇
  2003年   3132篇
  2002年   2973篇
  2001年   3267篇
  2000年   3076篇
  1999年   3095篇
  1998年   2822篇
  1997年   2650篇
  1996年   2569篇
  1995年   2405篇
  1994年   2377篇
  1993年   2326篇
  1992年   2556篇
  1991年   2404篇
  1990年   2261篇
  1989年   2217篇
  1988年   2178篇
  1987年   2207篇
  1986年   2173篇
  1985年   2431篇
  1984年   2517篇
  1983年   2322篇
  1982年   2373篇
  1981年   2341篇
  1980年   2186篇
  1979年   2210篇
  1978年   2182篇
  1977年   2137篇
  1976年   1954篇
  1975年   1999篇
  1974年   2046篇
  1973年   1955篇
  1972年   1531篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
53.
We investigated motivational and cognitive processes of behavior change with respect to mammography screening. One hundred forty-two women (ages 40 and older) recruited from three worksites answered a 41-item questionnaire consisting of statements based on constructs from the transtheoretical model of behavior change. Principal-components analysis identified two factors: a six-item component representing positive perceptions of mammography (Pros) and a six-item component representing avoidance of mammography (Cons). Analysis of variance showed that Pros, Cons, and a derived Decisional Balance measure (Pros minus Cons) were associated with stage of mammography adoption. Results are consistent with applications of the model to smoking cessation. The model is also discussed as it relates to other theories of behavior change and as a general strategy for analyzing perceptual data pertinent to health-related actions and intentions for behavioral change.  相似文献   
54.
Range of electric vehicles (EVs) has long been considered a major barrier in acceptance of electric mobility. We examined the nature of how range is experienced in an EV and whether variables from other adaptation contexts, notably stress, have explanatory power for inter‐individual differences in what we term comfortable range. Forty EVs were leased to a sample of users for a 6‐month field study. Qualitative and quantitative analyses of range experiences were performed, including regression analyses to examine the role of stress‐buffering personality traits and coping skills in comfortable range. Users appraised range as a resource to which they could successfully adapt and that satisfied most of their daily mobility needs. However, indicators were found that suggested suboptimal range utilisation. Stress‐buffering personality traits (control beliefs, ambiguity tolerance) and coping skills (subjective range competence, daily range practice) were found to play a substantial role in comfortable range. Hence, it may be possible to overcome perceived range barriers with the assistance of psychological interventions such as information, training, and interface design. Providing drivers with a reliable usable range may be more important than enhancing maximal range in an electric mobility system.  相似文献   
55.
56.
57.
58.
59.
60.
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