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41.
Biodiversity science in China has seen rapid growth over recent decades, ranging from baseline biodiversity studies to understanding the processes behind evolution across dynamic regions such as the Qinghai-Tibetan Plateau. We review research, including species catalogues; biodiversity monitoring; the origins, distributions, maintenance and threats to biodiversity; biodiversity-related ecosystem function and services; and species and ecosystems’ responses to global change. Next, we identify priority topics and offer suggestions and priorities for future biodiversity research in China. These priorities include (i) the ecology and biogeography of the Qinghai-Tibetan Plateau and surrounding mountains, and that of subtropical and tropical forests across China; (ii) marine and inland aquatic biodiversity; and (iii) effective conservation and management to identify and maintain synergies between biodiversity and socio-economic development to fulfil China''s vision for becoming an ecological civilization. In addition, we propose three future strategies: (i) translate advanced biodiversity science into practice for biodiversity conservation; (ii) strengthen capacity building and application of advanced technologies, including high-throughput sequencing, genomics and remote sensing; and (iii) strengthen and expand international collaborations. Based on the recent rapid progress of biodiversity research, China is well positioned to become a global leader in biodiversity research in the near future.  相似文献   
42.
Behaviour problems in early childhood have a lasting impact on cognitive development and education attainment in later adolescence and into adulthood. Here we address the relationship conduct and hyperactivity problems at school entrance, and vocabulary acquisition in adolescence. We compare performance in identical assessments across two generations of British children born 30 years apart in 1970 (n = 15,676) and 2000/2 (n = 16,628) and find that both conduct and hyperactivity problems have a negative association with later vocabulary in both generations. We take advantage of rich longitudinal birth cohort data and establish that these relationships hold once family socioeconomic status and a child’s personal characteristics and earlier vocabulary acquisition are taken into account. We also find that teenagers today achieved substantively lower scores in the vocabulary assessment compared to their counterparts born 30 years earlier, and that this holds across all categories within each of the family and individual characteristics considered in this article. As vocabulary and language skills are key prerequisites for wider learning, we discuss implications the findings have for education policies.  相似文献   
43.
The present, study was conducted to determine the level of malondialdehyde (MDA) as an index of free radial induced lipid peroxidation and antioxidant vitamins-vitamins A, vitamin C and vitamin E in 75 confirmed cases of urolithiasis. Significantly high level of MDA (p<0.001) with significantly low levels of vitamin E (p<0.001) and vitamin A (p<0.001) with no significant decrease in vitamin C (p>0.05) were observed in the plasma of urolithiasis cases as compared to normal controls. In conclusion, it appears that a role of lipid peroxidation and oxidative function exists in the pathogenesis of urolithiasis. But, the exact mechanism how this occurs remains to be elucidated.  相似文献   
44.
Case studies on five different modes of computer-based learning (CBL) were conducted in two secondary schools. The five CBL modes are: a) CBL for revising a previously taught topic; b) CBL for introducing a new topic; c) CBL for vocabulary acquisition; d) CBL for learning problem-solving and information-processing skills; and e) use of the word-processor for learning grammar and writing skills. This paper describes the implementation procedures and evaluation findings, and discusses the potential of these five CBL modes.  相似文献   
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In Aotearoa New Zealand, many early childhood teachers gain their teaching qualification via distance study while working in an early childhood centre. Early childhood teachers work in a team environment, and it is important to understand more about how distance students negotiate changes in their workplace practice as their professional knowledge develops. This article draws on a study that explores students’ experiences of distance teacher education as a process of changing participation in the workplace. Distance study supported increasingly confident participation as students saw more meaning in their daily work. The students’ identities and their workplace cultures and practices influenced what students paid attention to and the decisions they made when negotiating changes within their teams. Their experiences suggest that strengthening students’ relational agency at work is a useful focus for distance early childhood teacher education programmes.  相似文献   
48.
A new item parameter replication method is proposed for assessing the statistical significance of the noncompensatory differential item functioning (NCDIF) index associated with the differential functioning of items and tests framework. In this new method, a cutoff score for each item is determined by obtaining a (1 −α) percentile rank score from a frequency distribution of NCDIF values under the no-DIF condition by generating a large number of item parameters based on the item parameter estimates and their variance-covariance structures from a computer program such as BIILOG-MG3. This cutoff for each item can be used as the basis for determining whether a given NCDIF index is significantly different from zero. This new method has definite advantages over the current method and yields cutoff values that are tailored to a particular data set and a particular item. A Monte Carlo assessment of this new method is presented and discussed.  相似文献   
49.
Abstract

The subjects that young people study from age 14 onwards may have important consequences for their future academic and labour market outcomes. These decisions are shaped by the schools in which they find themselves. Schools also face constraints of their own. This paper explores the extent to which individuals’ decisions are affected by the school they attend and to what extent this is affected by the composition of schools in terms of academic attainment, gender, and socioeconomic background. We use multi-level variance decomposition models applied to administrative data on the subjects that young people in mainstream state-funded schools in England study between ages 14 and 16. Our results highlight the important role that constraints on schools play in subject choice decisions. We also note the particular role of attending a non-selective school within a selective schooling district.  相似文献   
50.
Kenya experienced a severe drought and temporary food shortage during a study on mild malnutrition. Effects of the temporary food shortage on energy intake, weight, and behaviors were evaluated in schoolchildren and in toddlers and their mothers. Schoolchildren were seriously affected, showing significant declines in their energy intake, age-corrected weight, activity on the playground, and classroom attention. Toddlers appear to have been somewhat protected since their energy intake, weight, and play and language behaviors were stable. Maternal caregiving of toddlers declined for the group as a whole, but individually those mothers who maintained family food levels delegated responsibility for toddlers to other caregivers. While the food shortage affected poorer families more than those of higher SES, declines in the behaviors of schoolchildren occurred regardless of SES and previous level of nutrition, suggesting that food shortages can have behavioral consequences for schoolchildren in all communities.  相似文献   
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