全文获取类型
收费全文 | 2151篇 |
免费 | 63篇 |
专业分类
教育 | 1761篇 |
科学研究 | 31篇 |
各国文化 | 45篇 |
体育 | 101篇 |
综合类 | 1篇 |
文化理论 | 6篇 |
信息传播 | 269篇 |
出版年
2023年 | 13篇 |
2022年 | 25篇 |
2021年 | 31篇 |
2020年 | 71篇 |
2019年 | 112篇 |
2018年 | 133篇 |
2017年 | 164篇 |
2016年 | 136篇 |
2015年 | 84篇 |
2014年 | 110篇 |
2013年 | 505篇 |
2012年 | 81篇 |
2011年 | 93篇 |
2010年 | 62篇 |
2009年 | 68篇 |
2008年 | 68篇 |
2007年 | 57篇 |
2006年 | 44篇 |
2005年 | 33篇 |
2004年 | 36篇 |
2003年 | 41篇 |
2002年 | 36篇 |
2001年 | 16篇 |
2000年 | 37篇 |
1999年 | 19篇 |
1998年 | 15篇 |
1997年 | 16篇 |
1996年 | 18篇 |
1995年 | 14篇 |
1994年 | 14篇 |
1993年 | 6篇 |
1992年 | 7篇 |
1991年 | 8篇 |
1990年 | 3篇 |
1989年 | 5篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有2214条查询结果,搜索用时 0 毫秒
101.
102.
Environment and Policy Factors Shaping Global E-Commerce Diffusion: A Cross-Country Comparison 总被引:1,自引:0,他引:1
This article examines the key global, environmental and policy factors that act as determinants of e-commerce diffusion. It is based on systematic comparison of case studies from 10 countries--Brazil, China, Denmark, France, Germany, Mexico, Japan, Singapore, Taiwan, and the United States. It finds that B2B e-commerce seems to be driven by global forces, whereas B2C seems to be more of a local phenomenon. A preliminary explanation for this difference is that B2B is driven by global competition and MNCs that "push" e-commerce to their global suppliers, customers, and subsidiaries. This in turn creates pressures on local companies to adopt e-commerce to stay competitive. In contrast, B2C is "pulled" by consumer markets, which are mainly local and therefore divergent. While all consumers desire convenience and low prices, consumer preferences and values, national culture, and distribution systems differ markedly across countries and define differences in local consumer markets. These findings support the transformation perspective about globalization and its impacts. In terms of policy, the case studies suggest that enabling policies such as trade and telecommunications liberalization are likely to have the biggest impact on e-commerce, by making ICT and Internet access more affordable to firms and consumers, and increasing pressure on firms to adopt e-commerce to compete. Specific e-commerce legislation appears not to have as big an impact, although inadequate protection for both buyers and sellers in some countries suggests that mechanisms need to be developed to ensure greater confidence in doing business online. 相似文献
103.
Windsor J Benigno JP Wing CA Carroll PJ Koga SF Nelson CA Fox NA Zeanah CH 《Child development》2011,82(4):1040-1046
This report examines 174 young children's language outcomes in the Bucharest Early Intervention Project, the first randomized trial of foster placement after institutional care. Age of foster placement was highly correlated with language outcomes. Placement by 15 months led to similar expressive and receptive language test scores as typical age peers at 30 and 42 months. Placement from 15 to 24 months also led to dramatic language improvement. In contrast, children placed after 24 months had the same severe language delays as children in institutional care. Language samples at 42 months confirmed that placement after 24 months led to lower expressive skill. 相似文献
104.
Brian R. Belland Krista D. Glazewski Jennifer C. Richardson 《Instructional Science》2011,39(5):667-694
Students engaged in problem-based learning (PBL) units solve ill-structured problems in small groups, and then present arguments
in support of their solution. However, middle school students often struggle developing evidence-based arguments (Krajcik
et al., J Learn Sci 7:313–350, 1998). Using a mixed method design, the researchers examined the use of computer-based argumentation scaffolds, called the Connection Log, to help middle school students build evidence-based arguments. Specifically we investigated (a) the impact of computer-based
argumentation scaffolds on middle school students’ construction of evidence-based arguments during a PBL unit, and (b) scaffold
use among members of two small groups purposefully chosen for case studies. Data sources included a test of argument evaluation
ability, persuasive presentation rating scores, informal observations, videotaped class sessions, and retrospective interviews.
Findings included a significant simple main effect on argument evaluation ability among lower-achieving students, and use
of the scaffolds by the small groups to communicate and keep organized. 相似文献
105.
106.
Harnessing technology to improve formative assessment of student conceptions in STEM: forging a national network 总被引:2,自引:0,他引:2
Haudek KC Kaplan JJ Knight J Long T Merrill J Munn A Nehm R Smith M Urban-Lurain M 《CBE life sciences education》2011,10(2):149-155
Concept inventories, consisting of multiple-choice questions designed around common student misconceptions, are designed to reveal student thinking. However, students often have complex, heterogeneous ideas about scientific concepts. Constructed-response assessments, in which students must create their own answer, may better reveal students' thinking, but are time- and resource-intensive to evaluate. This report describes the initial meeting of a National Science Foundation-funded cross-institutional collaboration of interdisciplinary science, technology, engineering, and mathematics (STEM) education researchers interested in exploring the use of automated text analysis to evaluate constructed-response assessments. Participants at the meeting shared existing work on lexical analysis and concept inventories, participated in technology demonstrations and workshops, and discussed research goals. We are seeking interested collaborators to join our research community. 相似文献
107.
Narelle S. Cox Karen O. McKay Jennifer M. Follett Jennifer A. Alison 《Cardiopulmonary Physical Therapy Journal》2011,22(1):16-19
Purpose: This case series describes the effect of home intravenous (IV) antibiotic therapy on spirometry and exercise capacity in a group of children with cystic fibrosis (CF). Methods: Outcomes from 10 children with CF who were prescribed a 14-day course of home IV antibiotics for a respiratory exacerbation are reported. All children performed spirometry and a modified shuttle test (MST) before and after 14-days of home IV therapy. Results: After 14 days, FEV1 increased by mean (± SE) 12 ± 4 % (p < 0.05) but mean MST did not improve compared to baseline. All children improved or maintained spirometry values with treatment, however, only 5 improved MST distance. Conclusion: After 14 days of home IV antibiotic therapy, a significant improvement in spirometry, but not exercise capacity, was seen in this small series of children with CF. The lack of improvement in exercise capacity for all children following home IV antibiotic therapy suggests factors other than spirometry determine exercise capacity. Identifying and investigating the factors that influence exercise capacity during home IV antibiotic therapy requires further investigation.Key Words: cystic fibrosis, home IV therapy, FEV1, Modified Shuttle Test 相似文献
108.
Using objectification theory (Fredrickson & Roberts, 1997), this study tested the interaction between self-objectification, appearance evaluation, and self-esteem in predicting body satisfaction and mood states. Participants (N = 93) were physically active female university students. State self-objectification was manipulated by participants wearing tight revealing exercise attire (experimental condition) or baggy exercise clothes (control condition). Significant interactions emerged predicting depression, anger, fatness, and satisfaction with body shape and size. For participants in the self-objectification condition who had low (as opposed to high) appearance evaluation, low self-esteem was associated with high depression, anger, and fatness and low satisfaction with body shape and size. In contrast, for participants with high self-esteem, these mood and body satisfaction states were more favorable irrespective of their levels of appearance evaluation. For female exercisers, self-esteem-enhancing strategies may protect against some of the negative outcomes of self-objectification. 相似文献
109.
Li Mingyang Donnelly-Hermosillo Dermot Francis Click Jennifer 《Journal of Science Education and Technology》2022,31(1):27-51
Journal of Science Education and Technology - Numerous studies illustrate the value of simulations or project-based learning approaches to enhance the learning of science. Simulations can help... 相似文献
110.
Lee Sunmin Adair Jennifer Keys Payne Katherina A. Barry David 《Early Childhood Education Journal》2022,50(7):1083-1095
Early Childhood Education Journal - Young children’s ideas of fairness have been studied in a range of laboratory settings with findings that children see fairness as equal distribution of... 相似文献