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181.
Eric Winsberg 《Metascience》2009,18(2):265-268
  相似文献   
182.
中国情报学论文地区合作网研究   总被引:1,自引:0,他引:1  
以近三年来发表在中国情报学核心期刊上的论文数据为基础,利用统计方法及社会关系网络分析法,描绘了中国情报学领域论文的地区分布特征,进而揭示了情报学研究在中国各省、直辖市之间以及国际间交流及合作现状及存在的问题.  相似文献   
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184.
The sociopolitical context of Norway includes low poverty rates and universal access to subsidized and regulated Early Childhood Education and Care (ECEC). In this context, the association between family income dynamics and changes in early child behavior problems was investigated, as well as whether high‐quality ECEC buffers children from the effects of income dynamics. In a population‐based sample (N = 75,296), within‐family changes in income‐to‐needs predicted changes in externalizing and internalizing problems (from ages 18 to 36 months), particularly for lower income children. For internalizing problems, ECEC buffered the effect of income‐to‐needs changes. These findings lend further support to the potential benefits of ECEC for children from lower income families.  相似文献   
185.
Marital conflict and conduct problems in Children of Twins   总被引:3,自引:0,他引:3  
The Children-of-Twins design was used to test whether associations between marital conflict frequency and conduct problems can be replicated within the children of discordant twin pairs. A sample of 2,051 children (age 14-39 years) of 1,045 twins was used to estimate the genetic and environmental influences on marital conflict and determine whether genetic or environmental selection processes underlie the observed association between marital conflict and conduct problems. Results indicate that genetic and nonshared environmental factors influence the risk of marital conflict. Furthermore, genetic influences mediated the association between marital conflict frequency and conduct problems. These results highlight the need for quasiexperimental designs in investigations of intergenerational associations.  相似文献   
186.
The purpose of the current study was to survey and interview caregivers of children with disabilities (ages 2–5 years) to obtain their input as to whether current playground equipment meets their child's needs. A total of 149 participants agreed to participate. Caregivers (i) indicated that their child with a disability could not fully participate in the playground's offerings, (ii) felt that the playground was not appropriate for their child with a disability and (iii) dreamed of a fully inclusive playground that met their child's needs. The results also demonstrate that social participation barriers continue to remain for families who have children with disabilities despite the passing of international human rights standards targeting individuals with disabilities and a global focus in improving the overall well‐being of children with disabilities.  相似文献   
187.
Perched on the Mason-Dixon line, Baltimore ignored calls for resistance from its southern neighbors by becoming one of the first cities in the country to comply withBrown. By the beginning of the 1955 school year, leaders had implemented a desegregation plan, and Baltimore was being applauded for the early and peaceful integration of its public schools. Within a few years, however, the praise faded as it became clear that Baltimore still suffered from de facto segregation. Faced with this reality, the school board refused to take the steps necessary to remedy the problem, instead shifting the blame to society at large. This failure by the board started a pattern of abandonment by school leadership that culminated in 1991 with the privatization of several of Baltimore's public schools. The result of this abandonment is a crippled school system that still has not dealt with issues of race and equality.  相似文献   
188.
基于三阶段DEA的中国区域二氧化碳排放绩效评价研究   总被引:3,自引:2,他引:3  
华坚  任俊  徐敏  Eric Fong 《资源科学》2013,35(7):1447-1454
要在促进社会经济发展的同时减少二氧化碳排放量,关键在于提高二氧化碳排放绩效.客观正确地评估中国各省份经济发展过程中的二氧化碳排放绩效具有重要现实意义.文章从效率的角度,界定二氧化碳排放绩效的概念,将二氧化碳排放作为非期望产出纳入全要素研究框架,探索性地利用三阶段DEA方法和线性数据转换函数法来评价中国省际区域的二氧化碳排放绩效,剔除了环境变量和随机误差对结果的影响,为真实测度二氧化碳排放绩效提供了可行的方法.结果表明,传统DEA测度的二氧化碳排放平均技术效率和纯技术效率被低估,而平均规模效率被高估;中国区域间二氧化碳排放绩效发展显著不平衡,呈现出“东>西>中”的格局,与传统的经济格局存在一定出入.  相似文献   
189.
IntroductionIt is often quoted that 70% of clinical decisions are based on laboratory results, but the evidence to substantiate this claim is lacking. Since clinical guidelines aim to document best-practice decision making for specific disease conditions, inclusion of any laboratory test means that the best available evidence is recommending clinicians use it. Cardiovascular disease (CVD) is the world’s most common cause of mortality, so this study reviewed all CVD guidelines published by five national/international authorities to determine what proportion of them recommended laboratory testing.Materials and methodsFive leading CVD guidelines were examined, namely the European Society of Cardiology (ESC), the UK National Institute for Health and Clinical Excellence (NICE), the American College of Cardiology (ACC), the Australian Heart Foundation (AHF) and the Cardiac Society of Australia and New Zealand (CSANZ).ResultsA total of 101 guidelines were reviewed. Of the 33 individual ESC guidelines relating to CVD, 24/33 made a direct reference to the use of clinical laboratory tests in either diagnosis or follow-up treatment. The same applied to 15/20 of NICE guidelines, 24/32 from the ACC and 15/16 from the AHF/CSANZ. Renal function and blood count testing were the most recommended (39 and 26 times), with lipid, troponin and natriuretic peptide measurement advocated 25, 19 and 19 times respectively.ConclusionsThis study has shown that laboratory testing is advocated by between 73% and 94% of individual CVD guideline recommendations from five national/international authorities. This provides an index to assess the potential value of laboratory medicine to healthcare.  相似文献   
190.
Pigeons' keypecking was reinforced by food on baseline schedules of multiple variable interval (VI) x VI x and on contrast schedules of multiple VI x VI y. Deprivation of food was varied by maintaining subjects at 75%, 85%, and 95% (+/- 2%) of their free-feeding weights. Positive and negative behavioral contrast were observed. The size of the contrast was not systematically altered by changes in deprivation. Positive and negative contrast were both larger later in the session than they were earlier. Within-session decreases in responding were steeper for the baseline than for the contrast schedules for positive contrast. Within-session decreases were steeper for the contrast than for the baseline schedules for negative contrast. These results were predicted by the idea that different amounts of habituation to the reinforcer during the baseline and contrast schedules contribute to behavioral contrast. The results show that contrast occurs under conditions that reduce the effect of the following component. The results support the assumption that positive and negative contrast are produced by symmetrical theoretical variables.  相似文献   
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