全文获取类型
收费全文 | 10127篇 |
免费 | 143篇 |
国内免费 | 11篇 |
专业分类
教育 | 7114篇 |
科学研究 | 1218篇 |
各国文化 | 82篇 |
体育 | 715篇 |
综合类 | 3篇 |
文化理论 | 76篇 |
信息传播 | 1073篇 |
出版年
2023年 | 55篇 |
2022年 | 65篇 |
2021年 | 134篇 |
2020年 | 191篇 |
2019年 | 269篇 |
2018年 | 421篇 |
2017年 | 381篇 |
2016年 | 364篇 |
2015年 | 215篇 |
2014年 | 347篇 |
2013年 | 1724篇 |
2012年 | 285篇 |
2011年 | 306篇 |
2010年 | 272篇 |
2009年 | 244篇 |
2008年 | 269篇 |
2007年 | 232篇 |
2006年 | 215篇 |
2005年 | 193篇 |
2004年 | 204篇 |
2003年 | 161篇 |
2002年 | 155篇 |
2001年 | 216篇 |
2000年 | 214篇 |
1999年 | 199篇 |
1998年 | 110篇 |
1997年 | 138篇 |
1996年 | 116篇 |
1995年 | 84篇 |
1994年 | 102篇 |
1993年 | 72篇 |
1992年 | 170篇 |
1991年 | 136篇 |
1990年 | 118篇 |
1989年 | 148篇 |
1988年 | 127篇 |
1987年 | 99篇 |
1986年 | 111篇 |
1985年 | 106篇 |
1984年 | 80篇 |
1983年 | 90篇 |
1982年 | 61篇 |
1981年 | 65篇 |
1980年 | 59篇 |
1979年 | 103篇 |
1978年 | 64篇 |
1977年 | 62篇 |
1976年 | 50篇 |
1974年 | 57篇 |
1973年 | 51篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
53.
B. G. C. Maisonneuve T. Honegger J. Cordeiro O. Lecarme T. Thiry D. Fuard K. Berton E. Picard M. Zelsmann D. Peyrade 《Biomicrofluidics》2016,10(2)
With the rise of microfluidics for the past decade, there has come an ever more pressing need for a low-cost and rapid prototyping technology, especially for research and education purposes. In this article, we report a rapid prototyping process of chromed masks for various microfluidic applications. The process takes place out of a clean room, uses a commercially available video-projector, and can be completed in less than half an hour. We quantify the ranges of fields of view and of resolutions accessible through this video-projection system and report the fabrication of critical microfluidic components (junctions, straight channels, and curved channels). To exemplify the process, three common devices are produced using this method: a droplet generation device, a gradient generation device, and a neuro-engineering oriented device. The neuro-engineering oriented device is a compartmentalized microfluidic chip, and therefore, required the production and the precise alignment of two different masks. 相似文献
54.
The authors examined the relationship between stress, adaptive coping, and life satisfaction among college students who reported having a friend or family member with eating disorder symptomatology. A hierarchical regression confirmed the study's hypotheses. Higher stress was linked with less life satisfaction. After stress was controlled, plan coping had a beneficial influence on life satisfaction. College counselors can use these findings when choosing interventions for clients who are close to someone with an eating disorder. 相似文献
55.
56.
57.
58.
Dylan J.H.A. Henssen Loes van den Heuvel Guido De Jong Marc A.T.M. Vorstenbosch Anne-Marie van Cappellen van Walsum Marianne M. Van den Hurk Jan G.M. Kooloos Ronald H.M.A. Bartels 《Anatomical sciences education》2020,13(3):353-365
Neuroanatomy education is a challenging field which could benefit from modern innovations, such as augmented reality (AR) applications. This study investigates the differences on test scores, cognitive load, and motivation after neuroanatomy learning using AR applications or using cross-sections of the brain. Prior to two practical assignments, a pretest (extended matching questions, double-choice questions and a test on cross-sectional anatomy) and a mental rotation test (MRT) were completed. Sex and MRT scores were used to stratify students over the two groups. The two practical assignments were designed to study (1) general brain anatomy and (2) subcortical structures. Subsequently, participants completed a posttest similar to the pretest and a motivational questionnaire. Finally, a focus group interview was conducted to appraise participants’ perceptions. Medical and biomedical students (n = 31); 19 males (61.3%) and 12 females (38.7%), mean age 19.2 ± 1.7 years participated in this experiment. Students who worked with cross-sections (n = 16) showed significantly more improvement on test scores than students who worked with GreyMapp-AR (P = 0.035) (n = 15). Further analysis showed that this difference was primarily caused by significant improvement on the cross-sectional questions. Students in the cross-section group, moreover, experienced a significantly higher germane (P = 0.009) and extraneous cognitive load (P = 0.016) than students in the GreyMapp-AR group. No significant differences were found in motivational scores. To conclude, this study suggests that AR applications can play a role in future anatomy education as an add-on educational tool, especially in learning three-dimensional relations of anatomical structures. 相似文献
59.
In many Western science systems, funding structures increasingly stimulate academic research to contribute to practical applications,
but at the same time the rise of bibliometric performance assessments have strengthened the pressure on academics to conduct
excellent basic research that can be published in scholarly literature. We analyze the interplay between these two developments
in a set of three case studies of fields of chemistry in the Netherlands. First, we describe how the conditions under which
academic chemists work have changed since 1975. Second, we investigate whether practical applications have become a source
of credibility for individual researchers. Indeed, this turns out to be the case in catalysis, where connecting with industrial
applications helps in many steps of the credibility cycle. Practical applications yield much less credibility in environmental
chemistry, where application-oriented research agendas help to acquire funding, but not to publish prestigious papers or to
earn peer recognition. In biochemistry practical applications hardly help in gaining credibility, as this field is still strongly
oriented at fundamental questions. The differences between the fields can be explained by the presence or absence of powerful
upstream end-users, who can afford to invest in academic research with promising long term benefits. 相似文献
60.
Bahar Köymen Cathal O’Madagain Andreas Domberg Michael Tomasello 《Child development》2020,91(3):685-693
In collaborative problem solving, children produce and evaluate arguments for proposals. We investigated whether 3- and 5-year-olds (N = 192) can produce and evaluate arguments against those arguments (i.e., counter-arguments). In Study 1, each child within a peer dyad was privately given a reason to prefer one over another solution to a task. One child, however, was given further information that would refute the reasoning of their partner. Five-year-olds, but not 3-year-olds, identified and produced valid and relevant counter-arguments. In Study 2, 3-year-olds were given discourse training (discourse that contrasted valid and invalid counter-arguments) and then given the same problem-solving tasks. After training, 3-year-olds could also identify and produce valid and relevant counter-arguments. Thus, participating in discourse about reasons facilitates children’s counter-argumentation. 相似文献