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81.
We identified the perceptual–cognitive skills and player history variables that differentiate players selected or not selected into an elite youth football (i.e. soccer) programme in Australia. A sample of elite youth male football players (n?=?127) completed an adapted participation history questionnaire and video-based assessments of perceptual–cognitive skills. Following data collection, 22 of these players were offered a full-time scholarship for enrolment at an elite player residential programme. Participants selected for the scholarship programme recorded superior performance on the combined perceptual–cognitive skills tests compared to the non-selected group. There were no significant between group differences on the player history variables. Stepwise discriminant function analysis identified four predictor variables that resulted in the best categorization of selected and non-selected players (i.e. recent match-play performance, region, number of other sports participated, combined perceptual–cognitive performance). The effectiveness of the discriminant function is reflected by 93.7% of players being correctly classified, with the four variables accounting for 57.6% of the variance. Our discriminating model for selection may provide a greater understanding of the factors that influence elite youth talent selection and identification. 相似文献
82.
Purpose: The purpose of this study was to investigate whether loads carried in a backpack, with a load mass ranging from 0 to 20?kg, causes respiratory muscle fatigue. Methods: Eight males performed four randomised load carriage (LC) trials comprising 60?min walking at 6.5?km?h?1 wearing a backpack of either 0 (LC0), 10 (LC10), 15 (LC15) or 20?kg (LC20). Inspiratory (PImax) and expiratory (PEmax) mouth pressures were assessed prior to and immediately following each trial. Pulmonary gas exchange, heart rate (HR), blood lactate and glucose concentration and perceptual responses were recorded during the first and final 60?s of each trial. Results: Group mean PImax and PEmax were unchanged following 60-min load carriage in all conditions (p?>?.05). There was an increase over time in pulmonary gas exchange, HR and perceptions of effort relative to baseline measures during each trial (p?.05) with changes not different between trials (p?>?.05). Conclusions: These findings indicate that sub-maximal walking with no load or carrying 10, 15 or 20?kg in a backpack for up to 60?min does not cause respiratory muscle fatigue despite causing an increase in physiological, metabolic and perceptual parameters. 相似文献
83.
Marc S. Wells 《European Journal of Sport Science》2016,16(8):912-918
It has previously been shown that cyclists are unable to maintain a constant power output during cycle time-trials on hilly courses. The purpose of the present study is therefore to quantify these effects of power variation using a mathematical model of cycling performance. A hypothetical cyclist (body mass: 70?kg, bicycle mass: 10?kg) was studied using a mathematical model of cycling, which included the effects of acceleration. Performance was modelled over three hypothetical 40-km courses, comprising repeated 2.5-km sections of uphill and downhill with gradients of 1%, 3%, and 6%, respectively. Amplitude (5–15%) and distance (0.31–20.00?km) of variation were modelled over a range of mean power outputs (200–600?W) and compared to sustaining a constant power. Power variation was typically detrimental to performance; these effects were augmented as the amplitude of variation and severity of gradient increased. Varying power every 1.25?km was most detrimental to performance; at a mean power of 200?W, performance was impaired by 43.90?s (±15% variation, 6% gradient). However at the steepest gradients, the effect of power variation was relatively independent of the distance of variation. In contrast, varying power in parallel with changes in gradient improved performance by 188.89?s (±15% variation, 6% gradient) at 200?W. The present data demonstrate that during hilly time-trials, power variation that does not occur in parallel with changes in gradient is detrimental to performance, especially at steeper gradients. These adverse effects are substantially larger than those previously observed during flat, windless time-trials. 相似文献
84.
阳晓明 《四川师范大学学报(社会科学版)》2003,30(1):14-19
资本市场是公司外部治理机制的主导力量。股份水平既是管理绩效的显示,又具有巨大的财富效应。低估的股价可能引发代理权竞争和敌意接管。在我国,股价在公司治理中的约束机制和激励机制失效,其原因除了证券市场上股价形成机制的非理性因素外,更主要的原因在于我国公司治理结构中的先天性缺陷,其中关键是要解决公司股权结构中的国有股“一股独大”的问题。 相似文献
85.
传统农村金融安排由于其制度上存在缺陷,不能有效地满足广大农户的金融需求,农村金融资源流失严重。农村合作经济组织是伴随农业产业结构调整而衍生出来的一种中介组织。当其以中间变量的形式存在于农村金融组织与农户之间后,便可以通过其组织职能、载体职能及中介与服务职能派生出多种机制来有效地降低农村金融交易费用,增进农户融资绩效。 相似文献
86.
学习英语的最终目的是进行交际 ,语感与语言运用能力紧密相关 ,语感是外语课文教学的关键。本文从对课文整体教学角度来阐述如何培养学生的英语语感 相似文献
87.
This article reports an investigation of undergraduate motivation to learn. A Likert-type rating scale measure of motivation incorporated the general motivational dimensions identified by previous investigators, as well as a systematic theoretical framework that is more novel, and attempts to acknowledge the role of discipline-specific factors in motivation to learn. The motivation questionnaire was evaluated by measuring its success in explaining the academic achievement of biology, history, computing, planning, anthropology, geology, food science and nutrition, and education students (n = 380) in standard university assessments. The findings reveal that student performance is better explained by within- than across-discipline indexes of motivation, probably because some types of motivation lead to success in some disciplines but failure in others. Furthermore, items based on the theoretical framework developed to underpin the questionnaire (which distinguishes outcome from process incentives) were also found to explain more variation in student performance than general motivation items. Some practical implications of the findings are considered. 相似文献
88.
将绩效管理理论运用于高职学生管理中,采用现场研究方法设置试验组(45人)和控制组(71人),对试验组进行学生绩效管理控制。一个学期后考察学生德育、智育、体育和综合能力考评情况。试验结果表明在学生管理中采取绩效管理的思想与方法,可以显著提高学生绩效。 相似文献
89.
Nava Subramaniam 《Higher Education》2003,46(4):507-542
Since the late 1980s, Australian highereducation has undergone significant reforms andpolicy changes based on economic rationalismand modernisation of management. This paperexamines the outcomes of the reform processesbased on the career attributes, status andperceptions of work environment of academicaccountants in Australian universities.Similarities and differences between academicaccountants are explored fromcross-institutional and gender perspectives.The data provide insight into a number ofsystemic inequalities between the older andmore established universities and the neweruniversities. In specific, across-institutional analysis based on fouruniversity types: Sandstones/Redbricks,Gumtrees, Unitechs and New (Marginson 1999)indicates that academic accountants in Newuniversities employ a much lower proportion ofstaff with PhD qualification, a weakerpublication profile, and perceive greaterbarriers for conducting research in terms of ashortage of research mentors, colleagues withresearch experience, and post-graduatestudents. Further, the commitment to flexiblelearning and delivery strategies iscomparatively stronger in Unitechs, and posesadditional demands on accounting academics'overall workload. Perceptions of gender-baseddiscrimination by female academic accountantsare generally stronger than their malecounterparts, particularly, in Newuniversities. These results raise severalissues for academic accountants at both theinstitutional and individual level in terms ofequal employment opportunities, management ofresearch programmes, development of teachingstrategies and individual time management. 相似文献
90.
溴化锂吸收式制冷机的性能,通常指运行时所产生的冷量及与之相关的热力系数,蒸汽单耗等技术经济指标而言,分析影响溴冷机性能的各种因素,研究提高溴冷机性能,延长使用寿命的方案。 相似文献