全文获取类型
收费全文 | 671篇 |
免费 | 10篇 |
国内免费 | 1篇 |
专业分类
教育 | 565篇 |
科学研究 | 40篇 |
各国文化 | 9篇 |
体育 | 28篇 |
文化理论 | 4篇 |
信息传播 | 36篇 |
出版年
2022年 | 4篇 |
2021年 | 11篇 |
2020年 | 12篇 |
2019年 | 9篇 |
2018年 | 17篇 |
2017年 | 23篇 |
2016年 | 22篇 |
2015年 | 18篇 |
2014年 | 8篇 |
2013年 | 149篇 |
2012年 | 15篇 |
2011年 | 13篇 |
2010年 | 11篇 |
2009年 | 12篇 |
2008年 | 11篇 |
2007年 | 19篇 |
2006年 | 11篇 |
2005年 | 13篇 |
2004年 | 10篇 |
2003年 | 20篇 |
2002年 | 15篇 |
2001年 | 13篇 |
2000年 | 8篇 |
1999年 | 16篇 |
1998年 | 12篇 |
1996年 | 9篇 |
1995年 | 7篇 |
1994年 | 9篇 |
1993年 | 6篇 |
1992年 | 9篇 |
1991年 | 5篇 |
1990年 | 10篇 |
1989年 | 7篇 |
1988年 | 8篇 |
1987年 | 5篇 |
1986年 | 8篇 |
1985年 | 10篇 |
1984年 | 4篇 |
1983年 | 7篇 |
1982年 | 4篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 14篇 |
1978年 | 5篇 |
1977年 | 4篇 |
1976年 | 10篇 |
1973年 | 9篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1968年 | 5篇 |
排序方式: 共有682条查询结果,搜索用时 31 毫秒
101.
Francesco Sella Daniela Lucangeli Roi Cohen Kadosh Marco Zorzi 《Child development》2020,91(5):1456-1470
The ability to choose the larger between two numbers reflects a mature understanding of the magnitude associated with numerical symbols. The present study explores how the knowledge of the number sequence and memory capacity (verbal and visuospatial) relate to number comparison skills while controlling for cardinal knowledge. Preschool children’s (N = 140, Mage-in-months = 58.9, range = 41–75) knowledge of the directional property of the counting list as well as the spatial mapping of digits on the visual line were assessed. The ability to order digits on the visual line mediated the relation between memory capacity and number comparison skills while controlling for cardinal knowledge. Beyond cardinality, the knowledge of the (spatial) order of numbers marks the understanding of the magnitude associated with numbers. 相似文献
102.
Jing Cheng Dan Tong Qiang Zhang Yang Liu Yu Lei Gang Yan Liu Yan Sha Yu Ryna Yiyun Cui Leon Clarke Guannan Geng Bo Zheng Xiaoye Zhang Steven J Davis Kebin He 《国家科学评论(英文版)》2021,8(12)
Clean air policies in China have substantially reduced particulate matter (PM2.5) air pollution in recent years, primarily by curbing end-of-pipe emissions. However, reaching the level of the World Health Organization (WHO) guidelines may instead depend upon the air quality co-benefits of ambitious climate action. Here, we assess pathways of Chinese PM2.5 air quality from 2015 to 2060 under a combination of scenarios that link global and Chinese climate mitigation pathways (i.e. global 2°C- and 1.5°C-pathways, National Determined Contributions (NDC) pledges and carbon neutrality goals) to local clean air policies. We find that China can achieve both its near-term climate goals (peak emissions) and PM2.5 air quality annual standard (35 μg/m3) by 2030 by fulfilling its NDC pledges and continuing air pollution control policies. However, the benefits of end-of-pipe control reductions are mostly exhausted by 2030, and reducing PM2.5 exposure of the majority of the Chinese population to below 10 μg/m3 by 2060 will likely require more ambitious climate mitigation efforts such as China''s carbon neutrality goals and global 1.5°C-pathways. Our results thus highlight that China''s carbon neutrality goals will play a critical role in reducing air pollution exposure to the level of the WHO guidelines and protecting public health. 相似文献
103.
In this study, the effectiveness of detection of differential item functioning (DIF) and testlet DIF using SIBTEST and Poly-SIBTEST
were examined in tests composed of testlets. An example using data from a reading comprehension test showed that results from
SIBTEST and Poly-SIBTEST were not completely consistent in the detection of DIF and testlet DIF. Results from a simulation
study indicated that SIBTEST appeared to maintain type I error control for most conditions, except in some instances in which
the magnitude of simulated DIF tended to increase. This same pattern was present for the Poly-SIBTEST results, although Poly-SIBTEST
demonstrated markedly less control of type I errors. Type I error control with Poly-SIBTEST was lower for those conditions
for which the ability was unmatched to test difficulty. The power results for SIBTEST were not adversely affected, when the
size and percent of simulated DIF increased. Although Poly-SIBTEST failed to control type I errors in over 85% of the conditions
simulated, in those conditions for which type I error control was maintained, Poly-SIBTEST demonstrated higher power than
SIBTEST. 相似文献
104.
With the help of a team of expert biologist judges, the TREC Genomics track has generated four large sets of “gold standard”
test collections, comprised of over a hundred unique topics, two kinds of ad hoc retrieval tasks, and their corresponding
relevance judgments. Over the years of the track, increasingly complex tasks necessitated the creation of judging tools and
training guidelines to accommodate teams of part-time short-term workers from a variety of specialized biological scientific
backgrounds, and to address consistency and reproducibility of the assessment process. Important lessons were learned about
factors that influenced the utility of the test collections including topic design, annotations provided by judges, methods
used for identifying and training judges, and providing a central moderator “meta-judge”. 相似文献
105.
Christian M. Connell Jeffrey J. Vanderploeg Karol H. Katz Colleen Caron Leon Saunders Jacob Kraemer Tebes 《Child abuse & neglect》2009,33(4):218-228
ObjectivesThis study examined risk of maltreatment among children exiting foster care using a statewide sample of children reunified between 2001 and 2004 in Rhode Island. The objectives were: (1) to compare rates of maltreatment following parental reunification for youth in care as a result of maltreatment with those in care for other reasons; and (2) to assess the effects of child, family, and case characteristics on rates of re-maltreatment among children placed in foster care due to maltreatment.MethodA longitudinal dataset of all reunified cases was matched with state records of substantiated Child Protective Service (CPS) investigations. Two Cox proportional hazards models were tested. The first model compared rates of subsequent maltreatment for two groups: children in foster care as a result of maltreatment, and those in care for other reasons. The second model investigated the effects of child, family, and case characteristics on re-maltreatment rates for those in care as a result of maltreatment.ResultsChildren in foster care due to maltreatment were significantly more likely to be maltreated following reunification. Among children in foster care due to maltreatment, factors that raised risk for re-maltreatment included a previous foster care placement, exiting care from a non-relative foster home, and removal due to neglect. Older adolescents had lower rates of re-maltreatment than infants. Child neglect was the primary type of recurrent maltreatment that occurred following reunification.ConclusionsSupports are needed for families about to be reunified, particularly when the removal was prompted by incidents of abuse or neglect. Incidents of neglect are particularly likely and appropriate services should specifically target factors contributing to neglect. Cases involving youth with a history of repeated foster care placement or in which non-relative placements are utilized may need additional supports.Practice implicationsThis study suggests that services should be developed to minimize the risk for recurrent maltreatment following reunification. Services would be most useful for high-risk cases prior to reunification and during the first year following reunification. Understanding the risks associated with maltreatment will help guide development of appropriate interventions. 相似文献
106.
教育政策和实践总是处在困境之中,这是困扰政策制定者和实践者的问题.本文着力从教育政策和实践所面临的困境、如何处理困境的角度,重新审视政策和实践两者的关系,并从政策目标、政策工具和实践中的能力三方面对其展开论述,以期在冲突的基础上促进教育政策和实践间的融合. 相似文献
107.
Science Teachers’ Professional Development and Changes in Science Practical Assessment Practices: What are the Issues? 总被引:1,自引:0,他引:1
Phillip A. Towndrow Aik-Ling Tan Benny H. W. Yung Libby Cohen 《Research in Science Education》2010,40(2):117-132
This paper considers the circumstances under which science teachers can respond positively and productively to educational
policy reforms in the area of science practical assessment. To understand what might be involved in linking science teachers’
assessment capacities and their professional development, we present illustrative data from recent research studies conducted
in Singapore and Hong Kong showing contrasting approaches taken in the implementation of reforms in science practical assessment.
In Singapore, teachers worked together to select, discuss, clarify and refine their practices as they made decisions about
what to teach and assess. In Hong Kong, teachers took a critical stance towards the new policy and learnt from their own experiences
in order to build their confidence. With the same policy initiative, one group of teachers focused more on the technicalities
of complying with requirements imposed on them while in the other group had their professional consciousness of what they
thought was best for their students provoked so that their practices would be transformed. In an attempt to draw lessons for
other contexts in supporting the implementation of assessment policy reforms through professional development work, we identify
and discuss a range of factors in science teachers’ professional development that arise once in situ professional development work has started. Overall, our intent in this article is to recast assessment reform as a driver
or pivot in teachers’ professional development and learning. To do this it is necessary, we argue, to afford teachers’ experiences
and the processes involved in learning from them greater emphasis in order to ensure the continuance of innovation in the
assessment of laboratory-based work. 相似文献
108.
Over the past few decades, America’s social compact for higher education as a public good has effectively lapsed as government
support of higher education has diminished. Given the need for a highly educated workforce in today’s knowledge-based global
economy, we propose a new compact for higher education that couples increased funding with increased institutional accountability.
While the compact must retain academic freedom as an essential component of higher education, this autonomy must co-exist
with rigorous accountability standards. Accountability systems should be multifaceted, as different methodologies have differing
strengths and limitations. All systems should, however, inform the public and provide for institutional improvement. 相似文献
109.
Abstract The experiment was designed to compare the effects of isometric-isotonic (A), dynamic-overload (B), and free swing (C) exercise programs on the speed and strength of a lateral arm movement The 26 college men in each group—three experimental and one control—were given pre- and post-training speed and strength trials. Each experimental group performed its assigned exercise twice a week during the 10-week training period. Reliability coefficients for both strength and speed of movement measurements were found to be high. Following training there were significant speed increases in both the isometric-isotonic and dynamic-overload groups (t=10.06 and 8.10; however, the difference in speed gain between conditions was nonsignificant (F=.10). Also, strength increases in both of these groups were significant (t=8.81 and 3.08), with that of the isometric-isotonic group significantly greater than the dynamic-overload group (F=5.11). No significant speed or strength gains were registered by either the free swing or control group. 相似文献
110.