首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   121284篇
  免费   1907篇
  国内免费   243篇
教育   83780篇
科学研究   13414篇
各国文化   2000篇
体育   9767篇
综合类   195篇
文化理论   1113篇
信息传播   13165篇
  2021年   975篇
  2020年   1725篇
  2019年   2653篇
  2018年   3266篇
  2017年   3538篇
  2016年   3561篇
  2015年   2390篇
  2014年   3250篇
  2013年   27608篇
  2012年   2486篇
  2011年   2881篇
  2010年   2413篇
  2009年   2646篇
  2008年   2470篇
  2007年   2236篇
  2006年   2453篇
  2005年   2426篇
  2004年   3077篇
  2003年   2386篇
  2002年   2225篇
  2001年   2096篇
  2000年   1740篇
  1999年   1643篇
  1998年   1478篇
  1997年   1529篇
  1996年   1700篇
  1995年   1405篇
  1994年   1353篇
  1993年   1341篇
  1992年   1381篇
  1991年   1290篇
  1990年   1333篇
  1989年   1225篇
  1988年   1088篇
  1987年   1010篇
  1986年   1038篇
  1985年   1274篇
  1984年   1178篇
  1983年   1101篇
  1982年   1071篇
  1981年   1002篇
  1980年   960篇
  1979年   1080篇
  1978年   1046篇
  1977年   963篇
  1976年   871篇
  1975年   706篇
  1974年   702篇
  1973年   678篇
  1972年   526篇
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
31.
Classification is a defining feature of Para-sport, and sports-specific classification systems determined through multidisciplinary scientific research are required, i.e., evidence-based and focused on the relationship between the impairment and the key performance determinants. Data envelopment analysis (DEA) was applied as a classification tool using a directional distance function (DDF) model. The aim of the study was to test the DEA as a possible classification tool in cerebral palsy football. We analyse the performance of 56 international para-footballers with hypertonia, ataxia or athetosis, who completed a 20-test battery with DEA models. Five of the tests are included in the model (change of direction: Illinois agility test; jumping: standing broad jump, four bounds for distance, and triple hop with the non-dominant leg; 10-m sprint/acceleration; and ball dribbling, both in a straight line and following a trajectory), showing that players with less impairment exhibit the highest efficiency. This outcome suggests that DEA models might be feasible for detecting and discriminating the performance and magnitude of impairment in cerebral palsy football, with an objective ranking of the athletes in relation to different physical performance tests. This study also provides reference scores for decision-making during classification and guidance for further research in team Paralympic sports.  相似文献   
32.
Children are sensitive to a number of considerations influencing distributions of resources, including equality, equity, and reciprocity. We tested whether children use a specific type of reciprocity norm—market norms—in which resources are distributed differentially based strictly on amount offered in return. In two studies, 195 children 5–10 years and 60 adults distributed stickers to friends offering same or different amounts of money. Overall, participants distributed more equally when offers were the same and more unequally when offers were different. Although sensitive to why friends offered different amounts of money, children increasingly incorporated market norms into their distributions with age, as the oldest children and adults distributed more to those offering more, irrespective of the reasons provided.  相似文献   
33.
ABSTRACT

This article offers a textual analysis and semiotic reading of the Rich Kids of Tehran's (RKOT’s) Instagram page. Contributing to scholarship on Iranian youth media practices, this article interrogates how the RKOT navigate urban and rural space to engage in everyday processes of resistance against global and local systemic oppression. Grounding their visual representations on Instagram in historical and cultural context, the author questions how and when quotidian actions are transformed into political transgressions when posted on social media. This article emphasizes the RKOT's agency in shaping their brand by analyzing representations of gender performance, intertextuality, and national identity on Instagram.  相似文献   
34.
This study investigated the validity and reliability of the GymAware PowerTool (GPT). Thirteen resistance trained participants completed three visits, consisting of three repetitions of free-weight back squat, bench press, deadlift (80% one repetition maximum), and countermovement jump. Bar displacement, peak and mean velocity, peak and mean force, and jump height were calculated using the GPT, a three-dimensional motion capture system (Motion Analysis Corporation; 150 Hz), and a force plate (Kistler; 1500 Hz). Least products regression were used to compare agreeability between devices. A within-trial one-way ANOVA, typical error (TE; %), and smallest worthwhile change (SWC) were used to assess reliability. Regression analysis resulted in R2 values of >0.85 for all variables excluding deadlift mean velocity (R2 = 0.54–0.69). Significant differences were observed between visits 3-2 for bench press bar displacement (0.395 ± 0.055 m; 0.383 ± 0.053 m), and deadlift bar displacement (0.557 ± 0.034 m; 0.568 ± 0.034 m). No other significant differences were found. Low to moderate TE (0.6–8.8%) were found for all variables, with SWC ranging 1.7–7.4%. The data provides evidence that the GPT can be used to measure kinetic and kinematic outputs, however, care should be taken when monitoring deadlift performance.  相似文献   
35.
36.
ABSTRACT

The preservation of artefacts in museum collections is profoundly affected by fluctuations in temperature and, especially, relative humidity (RH). Since the late nineteenth century, many studies have been carried out on the best way to control hygrothermal conditions. In old buildings located in maritime temperate climate zones (such as Portugal) with strong thermal inertia, and which have low ventilation rate (relative to the volume and number of visitors), daily and seasonal hygroscopic inertia may help to assure the maintenance of RH stabilization conditions. The use of expensive active systems may be minimized through the passive behaviour of internal finishing building materials. This work presents the results of an experimental laboratory study conducted in a flow chamber to demonstrate the enormous potential of hygroscopic materials in stabilizing interior relative humidity. Based in these results and in-situ monitoring in a museum housed in a building, located in Porto, with a typical construction of the 1950s (granite masonry and reinforced concrete slabs), a numerical analysis was done to quantify the influence of hygroscopic materials in stabilizing the interior relative humidity.  相似文献   
37.
Cultural Studies of Science Education - In this paper, I engage with arguments put forth by Anna Günther-Hanssen in her article “A swing and a child: How scientific phenomena can come to...  相似文献   
38.
The value that willed body donors provide to medical education is priceless. Their precious gift helps to teach anatomy, spatial relationships between morphological structures, anatomical variation, and professionalism to medical students in a way that plastic models, podcasts, and lectures cannot. They are also an important resource for medical research and a wide variety of postgraduate training opportunities. While many body donation programs throughout the world are nonprofit organizations, there are body donation companies in the United States that sell donors for-profit. These “body brokers” have accumulated large profits from this business. It is incongruous that others would profit from such a priceless, freely donated gift. To prevent this incongruity, it is proposed that the international anatomical community develop a normative culture (a bioethos) for body donation programs. This would involve the conscious and systematic development of ethical principles for the day-to-day policies and practices of institutions that collect and use human bodies. With the development of this bioethos, a cultural shift in how donors are treated would occur and, over time, this would become the normal practice. These principles would become fundamental and foundational for the procurement and use of priceless human tissues.  相似文献   
39.
40.
Young children show social preferences for resource-rich individuals, although few studies have explored the causes underlying such preferences. We evaluate the viability of one candidate cause: Children believe that resource wealth relates to behavior, such that they expect the resource rich to be more likely to materially benefit others (including themselves) than the resource poor. In Studies 1 and 2 (ages 4–10), American children from predominantly middle-income families (= 94) and Indian children from lower income families (= 30) predicted that the resource rich would be likelier to share with others than the resource poor. In Study 3, American children (= 66) made similar predictions in an incentivized decision-making task. The possibility that children's expectations regarding giving contribute to prowealth preferences is discussed.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号