全文获取类型
收费全文 | 3732篇 |
免费 | 31篇 |
专业分类
教育 | 2602篇 |
科学研究 | 315篇 |
各国文化 | 56篇 |
体育 | 343篇 |
综合类 | 2篇 |
文化理论 | 50篇 |
信息传播 | 395篇 |
出版年
2022年 | 19篇 |
2021年 | 37篇 |
2020年 | 70篇 |
2019年 | 106篇 |
2018年 | 120篇 |
2017年 | 111篇 |
2016年 | 94篇 |
2015年 | 63篇 |
2014年 | 110篇 |
2013年 | 848篇 |
2012年 | 85篇 |
2011年 | 94篇 |
2010年 | 76篇 |
2009年 | 76篇 |
2008年 | 79篇 |
2007年 | 75篇 |
2006年 | 91篇 |
2005年 | 81篇 |
2004年 | 72篇 |
2003年 | 71篇 |
2002年 | 54篇 |
2001年 | 48篇 |
2000年 | 56篇 |
1999年 | 51篇 |
1998年 | 55篇 |
1997年 | 46篇 |
1996年 | 40篇 |
1995年 | 35篇 |
1994年 | 34篇 |
1993年 | 39篇 |
1992年 | 32篇 |
1991年 | 39篇 |
1990年 | 43篇 |
1989年 | 42篇 |
1988年 | 46篇 |
1987年 | 43篇 |
1986年 | 36篇 |
1985年 | 33篇 |
1984年 | 36篇 |
1983年 | 43篇 |
1982年 | 30篇 |
1981年 | 21篇 |
1980年 | 26篇 |
1979年 | 42篇 |
1978年 | 37篇 |
1977年 | 29篇 |
1976年 | 31篇 |
1974年 | 24篇 |
1973年 | 26篇 |
1969年 | 19篇 |
排序方式: 共有3763条查询结果,搜索用时 0 毫秒
71.
Thomas B. Åstebro 《Research Policy》2005,34(9):1404-1418
Research on technological opportunity has typically focused on the impact of broad industry characteristics on R&D intensity of firms. This study complements such approaches by examining the impact of a multidimensional vector that measures technological opportunity on independent inventors’ decisions to patent and commercialize inventions. Using data from 559 inventions and controlling for demand, appropriability, and competitive conditions, we found two of four tested dimensions of technological opportunity - technical performance and technical uncertainty - to be significant and important determinants of the likelihood of commercialization. Technical feasibility appears important in affecting patenting but unimportant in affecting commercialization. Technical significance carries a negative, although insignificant, sign conditioning commercialization. 相似文献
72.
Thomas E. Gaston Francesca Ounsworth Tessa Senders Sarah Ritchie Emma Jones 《Learned Publishing》2020,33(2):154-162
Previous research has found that researchers rank journal reputation and impact factor (IF) amongst the key selection criteria when choosing where to submit. We explored the actual effect upon submission numbers of several possible factors. We retrieved 10 years of submission data from over a thousand journals, as well as data on IF, retractions, and other factors. We performed statistical analysis and identified correlations. We also undertook case study research on the 55 most significant submission decreases. We found a statistically significant correlation between changes in IF, ISI percentage ranking, and changes in submissions numbers in subsequent years. We also found a statistically significant effect on submission numbers in the year following the publication of a retraction. Our case studies identified other factors, including negative feedback on the peer review process. Our findings regarding IF confirm previous indications about the significance of IF on submissions. We explain the correlation with retractions through the concept of ‘peer review reputation’. These results indicate that editors and publishers need to focus on a journal's peer review practices, as well as a journal's IF, if they are to maintain and grow submissions. 相似文献
73.
74.
75.
Thomas P. Reilly Owen W. Drudge James C. Rosen Dorene E. Loew Mariellen Fischer 《Psychology in the schools》1985,22(4):380-382
Twenty-six normal first-grade children (M = 7.0 years) were administered the WISC-R, the McCarthy Scales, and the Woodcock-Johnson Scales of Cognitive Ability. Two years later, their levels of academic achievement were determined by way of the WRAT and global teacher ratings of classroom performance. Pearson intercorrelations among the summary indices of the three intellectual measures were significant and uniformly high (rang. 77-.95). Correlations between first-grade ability scores and third-grade achievement measures also were significant (range .64-.90), suggesting strong predictive validity for each of the cognitive instruments. Though not significantly so, the correlations between the Woodcock-Johnson and achievement tended to be the highest. The results indicate that all three intellectual measures are appropriate for predicting later academic achievement in young school-aged children. 相似文献
76.
77.
Ernest A. Collabolletta Allen J. Fossbender Thomas Edward Bratter 《Psychology in the schools》1983,20(4):450-455
Before choosing to become involved with students who currently are abusing psychoactive substances, teachers must consider not only the potential consequences and payoffs to them professionally, but also what specifically they can do to help adolescents. This article presents some of the philosophical problems, and suggests potential solutions of how to relate to students who engage in potentially self-destructive, drug-related behavior. There is a need for teachers to become quasi-counselors and consultants, since they are the first line of defense against substance use and abuse. 相似文献
78.
Students need practice in decision making and problem solving, and sociodrama can provide this practice in a safe, nonthreatening context. It helps them to become aware of the typical ways they solve problems, and it increases both social and personal awareness. It may promote acceptance, cooperation, and cohesiveness in the classroom. Students readily adapt to this kind of activity and find it both enjoyable and stimulating. It is recommended as a useful method in the classroom and guidance and counseling setting for helping students understand their own behavior and the behavior of others. 相似文献
79.
The study, using 60 five-year-olds, investigated forms of play: (a) self-action, (b) puppet-action, and (c) control treatments and differences between the sexes on aural language recall scores using semantic, absolute, and syntactic criteria. The results of the preliminary analyses between treatment groups and sex differences on the Peabody Picture Vocabulary Test and the Harris-Goodenough Draw-A-Man Test indicated no significant main or interaction effects. The subjects in treatment groups and boys and girls were relatively homogeneous on receptive language IQ and motor coordination, respectively. With 3 × 2 factorial analysis of variance experiments run on aural language recall for each of the three criteria, several significant results were noted: (a) Using the semantic criteria for scoring aural language recall, self-action play yielded significantly higher mean scores than either puppet-action or control groups. (b) Using the semantic criteria to score aural language recall, girls yielded significantly higher scores than boys. (c) Using either the absolute or syntactic scoring criteria, the results of the analysis indicated no significant main or interaction effects on aural language recall. 相似文献
80.
Science, Technology & Society (STS) graduate programs primarily train graduate students to work in tenure track academic jobs. However, there are not enough tenure track academic jobs to match the supply of STS graduate students, nor does every STS graduate student want to become an academic. As a start to addressing these challenges, we hosted workshops before the 2017 Society for the Annual Meeting of the Society Studies of Science and the 2018 ST Global conference. In those workshops, panelists with PhDs in STS and related fields and working in non-academic faculty careers such as government agencies, non-profit foundations, and industry emphasized that students must showcase how their skills are useful to non-academic organizations. The panelists offered a wealth of stories on how their STS perspective supported their careers, yet most had faced implicit and explicit mentoring from STS faculty that ran counter to their career aspirations. The conversations centered on reframing research and conveying to potential employers how their STS training would support their future careers. A takeaway point that resonated with many participants was the need for STS graduate programs to rethink how they market themselves, recruit students, and critically reflect upon the measures of success. By implicitly steering graduate students solely towards an academic career, STS graduate training will miss an opportunity to make a positive impact on society. 相似文献