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   68942篇
  免费   2591篇
  国内免费   23篇
  2019年   801篇
  2018年   1189篇
  2017年   1213篇
  2016年   1381篇
  2015年   970篇
  2014年   1040篇
  2013年   4981篇
  2012年   2164篇
  2011年   2318篇
  2010年   1326篇
  2009年   1352篇
  2008年   1913篇
  2007年   1957篇
  2006年   1789篇
  2005年   2726篇
  2004年   2046篇
  2003年   1791篇
  2002年   1612篇
  2001年   2067篇
  2000年   2038篇
  1999年   1583篇
  1998年   772篇
  1997年   703篇
  1996年   706篇
  1995年   645篇
  1993年   646篇
  1992年   1329篇
  1991年   1245篇
  1990年   1219篇
  1989年   1110篇
  1988年   1086篇
  1987年   1057篇
  1986年   1118篇
  1985年   1133篇
  1984年   968篇
  1983年   880篇
  1982年   630篇
  1981年   625篇
  1979年   1034篇
  1978年   762篇
  1975年   847篇
  1974年   919篇
  1973年   1001篇
  1972年   833篇
  1971年   770篇
  1970年   684篇
  1969年   706篇
  1968年   902篇
  1967年   812篇
  1966年   681篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
Shkatov  Dmitry  Van Alten  Clint J. 《Studia Logica》2020,108(2):221-237
Studia Logica - We apply the theory of partial algebras, following the approach developed by Van Alten (Theor Comput Sci 501:82–92, 2013), to the study of the computational...  相似文献   
65.
This paper examines college students' attributions about suicide as a function of gender and context (athletic vs. relationship failure). Results indicated that male athletes who suicided were considered more emotionally well-adjusted compared to males who suicided because of a relationship failure and all females. Male and female athletes who suicided were seen as more competent and less distressed compared to those who suffered a failed relationship. Females were also seen as more distressed compared to males. These results are discussed in terms of a positive bias toward athletes in our society as well as gender stereotypes. Implications of these findings as well as methodological limitations are discussed.  相似文献   
66.
Reducing STDs and HIV/AIDS incidence requires campaigns designed to change knowledge, attitudes, and practices of risky sexual behavior. In China, a significant obstacle to such changes is the stigma associated with these diseases. Thus 1 campaign intervention strategy is to train credible community leaders to discuss these issues in everyday social venues. This study tested the effectiveness of such an approach on reducing HIV/AIDS stigma, across 2 years, from a sample of over 4,500 market vendors, in 3 conditions. Results showed an increasing growth in market communication about intervention messages, and concomitant declines in stigmatizing attitudes, across time, with the greatest changes in community popular opinion leaders, significant changes in intervention nonopinion leaders, and little change in the control markets.  相似文献   
67.
The ability to make egocentric distance estimates of a single point source of light, seen in darkness and without the cues of changing size and luminance, was investigated in sixteen observers. The attenuation required to maintain constant luminance, when the target was viewed from different distances, was shown to follow the inverse square law providing the angle subtended by the light was less than 20 s arc. Distance changes were also simulated by means of a split mirror which produced vergence cues, or by test lenses to provide accommodation cues. Over the range 0.5 to 9.2 m distance estimates were surprisingly accurate, although there was some overestimation of near and underestimation of far distances. Most observers made good judgements when only convergence cues were varied, whereas no observers made consistently good judgements when only accommodation cues were varied. The difficulties are discussed in terms of the accommodation-convergence link. When distance was simulated by changing convergence and accommodation cues, estimates were not as good as when real distance was changed. Since good estimates were made with brief target exposures, these judgements were not based on subsequent convergence or accommodation changes. It is suggested that the metric or reference against which the apparently absolute judgements were made was the efferent demand signal associated with a 'resting' position of convergence in darkness.  相似文献   
68.
69.
Telehealth research in the field of applied behavior analysis (ABA) has focused on the training and supervision of others to implement various behavior analytic procedures. Current guidelines for practicing telehealth suggest that direct telehealth services may be appropriate for some individuals diagnosed with autism spectrum disorder, but more research is needed. This study evaluated the effects of discrete trial teaching with instructive feedback in a dyad arrangement delivered directly via telehealth to teach tact relations to 6 children diagnosed with autism spectrum disorder. All participants and the experimenter were located in different physical locations. All participants learned their primary and secondary targets, and 5 of the participants acquired the observational primary and secondary targets without direct teaching. Areas of future research and clinical implications are discussed in the context of telehealth service delivery.  相似文献   
70.
This investigation evaluated the degree to which creativity training, idea generation instruction, and creative process impacted idea production, creativeness of solutions, and leadership effectiveness. Three sets of hypotheses were tested with a 114 groups of adults. First, groups whose members had some (i.e., one CPS course) or advanced training (i.e., graduate-level study in creativity or creativity professionals) were significantly more effective at idea generation than groups without training. Furthermore, leaders with some and advanced training were perceived to be significantly more effective than those with no creativity training. With respect to creativeness of solutions, the advanced training groups outperformed all others. The second set of hypotheses focused on the effectiveness of idea generation instruction (i.e., instructions without brainstorming, brainstorming, and brainstorming with criticism). Analysis revealed no significant difference for idea generation instruction relative to idea production or creativeness of solutions. The final set of hypotheses examined the use of a simple process structure for groups without prior creativity training (i.e., distinct phases for idea generation and solution development). Analysis revealed that those meetings that followed a simple process structure out performed groups that did not follow a process for both idea generation and creativeness of solutions. Further results are presented and implications discussed.  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