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   271篇
  免费   3篇
  国内免费   1篇
教育   152篇
科学研究   42篇
各国文化   2篇
体育   30篇
文化理论   28篇
信息传播   21篇
  2023年   1篇
  2022年   3篇
  2021年   4篇
  2020年   13篇
  2019年   25篇
  2018年   13篇
  2017年   21篇
  2016年   25篇
  2015年   7篇
  2014年   20篇
  2013年   42篇
  2012年   19篇
  2011年   10篇
  2010年   12篇
  2009年   4篇
  2008年   5篇
  2007年   7篇
  2006年   6篇
  2005年   5篇
  2004年   1篇
  2003年   2篇
  2002年   6篇
  2001年   1篇
  2000年   4篇
  1998年   1篇
  1997年   1篇
  1996年   3篇
  1995年   2篇
  1994年   4篇
  1993年   2篇
  1992年   2篇
  1991年   1篇
  1985年   1篇
  1983年   1篇
  1981年   1篇
排序方式: 共有275条查询结果,搜索用时 15 毫秒
61.
This article presents in summary a selection of the work conducted by OECD in the field of technology and education, which has been an on-going focus of OECD work since the 1980s. Recently, much of this has been under the heading of ‘New Millennium Learners’, but it has also included the widening of student achievement surveys towards digital literacy; reviews of e-learning in higher education, surveys on Open Education Resources (OER); technology as a source of innovation; and analyses of the digital resources market and educational technology patents. The article proposes the more holistic focus on ‘learning environments’ through which to analyse the very diverse ways in which technology can be integrated into education and as a design framework. This is drawn from a report of the OECD Innovative Learning Environments (ILE) project to be published in 2013, itself based on 40 case studies from different countries and regions. It suggests that contemporary learning environments should be: i) Innovating the ‘pedagogical core’; ii) Engaging the ‘Design/Redesign Leadership Circle’; iii) Widening connections and capacity through partnerships; and iv) Promoting 21st century effectiveness (based on the principles derived from the 2010 ILE learning research review). The article then applies this framework to show how technology shapes learning environments in many different ways. The article questions over-reliance on individuals navigating successfully to access non-formal learning opportunities and rejects the argument that learning institutions should simply adapt more adequately to available technologies. Instead, technology should be fully exploited in well-designed learning environments.  相似文献   
62.
The problem of constructing functional observers for linear systems with unknown inputs is considered. Necessary and sufficient conditions for the existence of a proper observer (without differentiations) are revisited. A simple and explicit form of a functional observer is presented. It is shown that when such observer is not proper, it is still possible to use the High-Order Sliding Mode differentiator to implement it. Nevertheless, in such case, additional conditions on the system and the unknown input are required.  相似文献   
63.
This paper evaluates the viability of using controversies in teaching. An educational project has been elaborated in which some historical-philosophical clashes were introduced into the classical syllabus of physics. The historical-philosophical controversy dealt with here, took place between the French physicists Biot and Ampère in the 19th century and referred to distinct interpretations of the Oersted experiment. This controversy was inserted into the syllabus of the 12th grade of a Brazilian secondary school.  相似文献   
64.

Introduction:

Two Italian adults arrived at the Emergency Department referring diarrhea, nausea and vomiting for 4 days; weakness, fatigue and visual hallucinations were also complained of. Patients reported the ingestion of some leaves of a plant, which they supposed to be “donkey ears”, a week before. Physical examination showed hypotension and bradycardia and ECG examination disclosed sinus rhythm and repolarization abnormalities (scooping of the ST-T complex) in both patients and a 2:1 AV block in the man.

Materials and methods:

Digoxin concentration was evaluated twice for each patient (at the admission and after 4 hours) by the automated immunoassay system ADVIA Centaur®. Digitoxin concentration was evaluated by liquid chromatography-mass spectrometry (LC-MS/MS).

Results:

Despite clinical picture was suggestive of digitalis intoxication, digoxin levels were undetectable. Due to the more severe clinical picture, the male patient was treated with anti-digoxin antibodies (Digifab®) achieving a good clinical improvement and remission of the AV block within two hours. Initial diagnosis was confirmed by LC-MS/MS showing high digitoxin concentrations, but digoxin was undetectable. Patients remained stable and 48 hours later were discharged from the hospital.

Conclusion:

Whereas digoxin determination frequently relies on monoclonal antibodies which do not cross-react to digitoxin, polyclonal antibodies constituting Digifab® recognize a large spectrum of cardiac glycosides, including digitoxin. This report emphasizes the primary role of the clinical approach to patients in the emergency setting and how an active communication and a continuous sharing of professional experiences between Laboratory and Clinicians ensure an early and correct diagnosis.  相似文献   
65.
Despite the growing body of research on work engagement, little is known about what drives work engagement among different age cohorts. This study aims to investigate whether engagement varies across age cohorts and examine the job resources that foster teacher engagement. A questionnaire was distributed to 537 teachers who were employed in elementary, lower and upper secondary school. Findings show that work engagement did indeed vary across the diverse age group and is influenced by different resources. In line with previous studies, data revealed that the engagement of younger teachers is driven by the opportunity for development and interaction with colleagues, while older employees appreciate the opportunity to see their competencies acknowledged. What is most noteworthy is the opportunity to design practices and to provide every age group with the appropriate set of motivators.  相似文献   
66.

Introduction:

In this work we report on the possible effect of the medical therapy on CDT concentration in a chronic alcohol abuser, with known medical history (July 2007 – April 2012) and alcohol abuse confirmed by relatives.

Case history:

At the end of 2007, patient displayed the following laboratory results: AST 137 U/L, ALT 120 U/L, GGT 434 U/L, MCV 101 fL and CDT 3.3%. On December 2007, after double coronary artery bypass surgery, he began a pharmacological treatment with amlodipine, perindopril, atorvastatin, isosorbide mononitrate, carvedilol, ticlopidine and pantoprazole. In the next months, until may 2011, the patient resumed alcohol abuse, as confirmed by relatives; however, CDT values were repeatedly found negative (0.8% and 1.1%) despite elevated transaminases and GGT, concurrent elevated ethyl glucuronide concentration (> 50 mg/L) and blood alcohol concentration (> 1 g/L). Alcohol consumption still continued despite increasing disulfiram doses ordered by an Alcohol Rehab Center. On May 2011, the patient was transferred to a private medical center where he currently lives.

Conclusions:

This study suggests the possibility that a medical therapy including different drugs may hamper the identification of chronic alcohol abusers by CDT.  相似文献   
67.
Improved understanding of mobility performance in wheelchair basketball is required to increase game performance. The aim of this study was to quantify the wheelchair-athlete activities of players in different field positions and of different playing standard during wheelchair basketball matches. From video analysis, absolute and relative duration and frequency of wheelchair movements and athlete control options were examined in 27 national standard and 29 international standard players during entire wheelchair basketball matches. Between-group factorial analysis of variances identified that national players drove more forward (42.6 ± 6.8 vs. 35.4 ± 3.7%; effect size Cohen’s d (ES) = 1.48) and started more often driving forward (33.9 ± 2.6 vs. 31.8 ± 2.8; ES = 0.77) during a match while the mean activity duration for a single driving forward activity was longer (4.3 ± 0.9 vs. 3.7 ± 0.6 s; ES = 0.75) than for international players. Furthermore, national players performed fewer rotational movements (21.8 ± 4.0 vs. 28.9 ± 7.8%; ES = –1.30) and started less often with the rotational movements (35.0 ± 3.6 vs. 40.5 ± 5.5; ES = –1.21) while the mean activity duration for a single rotation activity was shorter (2.1 ± 0.3 vs. 2.3 ± 0.3 s; ES = –0.67) than for international players. Differences in mobility performance among guard, forward and centre players were minimal. The results should help wheelchair basketball coaches specify wheelchair-handling training techniques and means to optimise wheelchair-athlete configurations.  相似文献   
68.
The aim of the current study was twofold: (1) to validate the use of action sport cameras for quantifying focus of visual attention in sailing and (2) to apply this method to examine whether an external focus of attention is associated with better performance in upwind sailing. To test the validity of this novel quantification method, we first calculated the agreement between gaze location measures and head orientation measures in 13 sailors sailing upwind during training regattas using a head mounted eye tracker. The results confirmed that for measuring visual focus of attention in upwind sailing, the agreement for the two measures was high (intraclass correlation coefficient (ICC) = 0.97) and the 95% limits of agreement were acceptable (between ?8.0% and 14.6%). In a next step, we quantified the focus of visual attention in sailing upwind as fast as possible by means of an action sport camera. We captured sailing performance, operationalised as boat speed in the direction of the wind, and environmental conditions using a GPS, compass and wind meter. Four trials, each lasting 1 min, were analysed for 15 sailors each, resulting in a total of 30 upwind speed trials on port tack and 30 upwind speed trials on starboard tack. The results revealed that in sailing – within constantly changing environments – the focus of attention is not a significant predictor for better upwind sailing performances. This implicates that neither external nor internal foci of attention was per se correlated with better performances. Rather, relatively large interindividual differences seem to indicate that different visual attention strategies can lead to similar performance outcomes.  相似文献   
69.
In this paper, we explore the work life of a scholar new to academia in her methods of leading informally. We discuss five vignettes that offer moments of learning and reflection, including reducing performance anxiety, privileging financial accountability, the rise of the virtual world, the impact of silence, and the potential for confrontation to strengthen working relationships. We offer suggestions as to how contemporary leaders may adapt to the freedom that artful action offers.  相似文献   
70.
In search of key-performance predictors in sailing, we examined to what degree visual search, movement behaviour and boat control contribute to skilled performance while rounding the windward mark. To this end, we analysed 62 windward mark roundings sailed without opponents and 40 windward mark roundings sailed with opponents while competing in small regattas. Across conditions, results revealed that better performances were related to gazing more to the tangent point during the actual rounding. More specifically, in the condition without opponents, skilled performance was associated with gazing more outside the dinghy during the actual rounding, while in the condition with opponents, superior performance was related to gazing less outside the dinghy. With respect to movement behaviour, superior performance was associated with the release of the trimming lines close to rounding the mark. In addition, better performances were related to approaching the mark with little heel, yet heeling the boat more to the windward side when being close to the mark. Potential implications for practice are suggested for each phase of the windward mark rounding.  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