全文获取类型
收费全文 | 15272篇 |
免费 | 196篇 |
国内免费 | 9篇 |
专业分类
教育 | 11240篇 |
科学研究 | 1288篇 |
各国文化 | 97篇 |
体育 | 1169篇 |
综合类 | 8篇 |
文化理论 | 95篇 |
信息传播 | 1580篇 |
出版年
2021年 | 112篇 |
2020年 | 168篇 |
2019年 | 266篇 |
2018年 | 375篇 |
2017年 | 388篇 |
2016年 | 361篇 |
2015年 | 222篇 |
2014年 | 300篇 |
2013年 | 2887篇 |
2012年 | 328篇 |
2011年 | 387篇 |
2010年 | 254篇 |
2009年 | 240篇 |
2008年 | 349篇 |
2007年 | 271篇 |
2006年 | 322篇 |
2005年 | 218篇 |
2004年 | 204篇 |
2003年 | 199篇 |
2002年 | 241篇 |
2001年 | 346篇 |
2000年 | 303篇 |
1999年 | 281篇 |
1998年 | 147篇 |
1997年 | 167篇 |
1996年 | 195篇 |
1995年 | 190篇 |
1994年 | 159篇 |
1993年 | 183篇 |
1992年 | 249篇 |
1991年 | 228篇 |
1990年 | 225篇 |
1989年 | 265篇 |
1988年 | 258篇 |
1987年 | 219篇 |
1986年 | 216篇 |
1985年 | 235篇 |
1984年 | 204篇 |
1983年 | 242篇 |
1982年 | 186篇 |
1981年 | 171篇 |
1980年 | 170篇 |
1979年 | 247篇 |
1978年 | 194篇 |
1977年 | 179篇 |
1976年 | 165篇 |
1975年 | 136篇 |
1974年 | 131篇 |
1973年 | 142篇 |
1971年 | 117篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
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
82.
Research in Higher Education - Since the turn of the twenty-first century, going to college has become increasingly financially difficult in the United States. Tuition prices continued to rise,... 相似文献
83.
84.
85.
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
86.
A Campus-Wide Investigation of Clicker Implementation: The Status of Peer Discussion in STEM Classes
Justin D. Lewin Erin L. Vinson MacKenzie R. Stetzer Michelle K. Smith 《CBE life sciences education》2016,15(1)
At the University of Maine, middle and high school teachers observed more than 250 university science, technology, engineering, and mathematics classes and collected information on the nature of instruction, including how clickers were being used. Comparisons of classes taught with (n = 80) and without (n = 184) clickers show that, while instructional behaviors differ, the use of clickers alone does not significantly impact the time instructors spend lecturing. One possible explanation stems from the observation of three distinct modes of clicker use: peer discussion, in which students had the opportunity to talk with one another during clicker questions; individual thinking, in which no peer discussion was observed; and alternative collaboration, in which students had time for discussion, but it was not paired with clicker questions. Investigation of these modes revealed differences in the range of behaviors, the amount of time instructors lecture, and how challenging the clicker questions were to answer. Because instructors can vary their instructional style from one clicker question to the next, we also explored differences in how individual instructors incorporated peer discussion during clicker questions. These findings provide new insights into the range of clicker implementation at a campus-wide level and how such findings can be used to inform targeted professional development for faculty. 相似文献
87.
88.
This study seeks to extend our knowledge of export market orientation (EMO) in the context of British universities with regard to recruitment of international students. Export marketing remains an area of limited focus in the marketization of higher education literature. The study predominantly follows a quantitative research design using survey methods. A sample of British universities was studied and partial least-squares analysis was performed. The findings indicate that four export higher education-specific variables are important drivers of EMO in universities. The paper also confirms EMO's direct effects on university export performance and its indirect effects mediated through university international reputation. In light of these findings, a number of implications are advanced for university management. The study also makes important theoretical contributions: it contributes to a growing body of literature on marketing of higher education; it enriches the export marketing literature by examining EMO in a service setting and it adds to the EMO–export performance relationship by examining the mediating role of international reputation. The findings are limited to British universities. Therefore, they may not be generalizable to other geographical areas. In addition, the results of this study were obtained from a small sample size and generalization of the findings to other higher education institutions should be made with caution. 相似文献
89.
90.
Victoria A. Roach Graham M. Fraser James H. Kryklywy Derek G.V. Mitchell Timothy D. Wilson 《Anatomical sciences education》2019,12(1):32-42
Research suggests that spatial ability may predict success in complex disciplines including anatomy, where mastery requires a firm understanding of the intricate relationships occurring along the course of veins, arteries, and nerves, as they traverse through and around bones, muscles, and organs. Debate exists on the malleability of spatial ability, and some suggest that spatial ability can be enhanced through training. It is hypothesized that spatial ability can be trained in low-performing individuals through visual guidance. To address this, training was completed through a visual guidance protocol. This protocol was based on eye-movement patterns of high-performing individuals, collected via eye-tracking as they completed an Electronic Mental Rotations Test (EMRT). The effects of guidance were evaluated using 33 individuals with low mental rotation ability, in a counterbalanced crossover design. Individuals were placed in one of two treatment groups (late or early guidance) and completed both a guided, and an unguided EMRT. A third group (no guidance/control) completed two unguided EMRTs. All groups demonstrated an increase in EMRT scores on their second test (P < 0.001); however, an interaction was observed between treatment and test iteration (P = 0.024). The effect of guidance on scores was contingent on when the guidance was applied. When guidance was applied early, scores were significantly greater than expected (P = 0.028). These findings suggest that by guiding individuals with low mental rotation ability “where” to look early in training, better search approaches may be adopted, yielding improvements in spatial reasoning scores. It is proposed that visual guidance may be applied in spatial fields, such as STEMM (science, technology, engineering, mathematics and medicine), surgery, and anatomy to improve student's interpretation of visual content. Anat Sci Educ. © 2018 American Association of Anatomists. 相似文献