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   75篇
  免费   2篇
教育   36篇
科学研究   23篇
各国文化   1篇
体育   10篇
文化理论   4篇
信息传播   3篇
  2023年   1篇
  2021年   1篇
  2020年   1篇
  2019年   1篇
  2018年   2篇
  2017年   3篇
  2016年   3篇
  2015年   6篇
  2014年   4篇
  2013年   10篇
  2012年   4篇
  2011年   6篇
  2010年   4篇
  2009年   3篇
  2008年   5篇
  2007年   1篇
  2004年   3篇
  2003年   3篇
  2002年   1篇
  2001年   2篇
  2000年   2篇
  1999年   2篇
  1996年   1篇
  1994年   1篇
  1993年   1篇
  1986年   1篇
  1985年   1篇
  1982年   1篇
  1980年   2篇
  1978年   1篇
排序方式: 共有77条查询结果,搜索用时 174 毫秒
71.
The present study aimed to compare the changes of direction on repeated sprint ability (RSA) vs. intensive repeated sprint ability (IRSA) protocols in basketball. Eighteen young male basketball players performed on RSA [10 × 30-m (15 + 15-m, one change of direction)] and IRSA [10 × 30-m (10 + 10 + 10-m, two changes of direction)]. A correlation matrix between RSA, IRSA, “squat jump (SJ)–countermovement jump (CMJ)”, footstep analysis and total distance in Yo-Yo intermittent recovery level 1 was performed. The best time, worst time, total time and the number of footsteps were significantly smaller in the RSA test compared to IRSA test (< 0.001), even though they were significantly correlated with each other (> 0.80, < 0.05). Blood lactate level and fatigue index did not show any difference between tests. The sensibility of the two tests assessed by the Bland–Altman analysis revealed a small bias (<1.5%) for almost all variables. Moreover, almost all time variables of the two tests were significantly correlated with the SJ (> 0.478, < 0.05), CMJ (r > 0.515, P < 0.05) and Yo-Yo (r > 0.489, P < 0.05) performances. The IRSA provided a reliable method for assessing specific sprint ability (with 10-m legs for IRSA ~2.3 s vs. 15 m for RSA ~3 s) with a closer link to basketball game’s actions (~2 s). Besides, IRSA could be an appropriate choice for assessing both RSA and changes of direction capacities in basketball players.  相似文献   
72.

Introduction

The aim of this study was to identify clinical variables which may be independently associated with positivity of a cardiac troponin I (cTnI) assay in a large population of patients admitted to the emergency department (ED).

Materials and methods

3166 subjects, with at least two troponin I tests ordered within 6 hours in the ED, were studied. Patient data were statistically analyzed to identify clinical associations with increased values of Troponin I.

Results

Although patients with diagnosis of acute coronary syndrome displayed troponin I values significantly higher than those of other groups, positivity to troponin I (> 40 ng/L) was also observed in patients with other clinical conditions. In multivariate analysis, age, elevated heart rate and electrocardiographyc changes were independently associated with troponin I positivity at admission. In the whole study population troponin I positivity exhibited high sensitivity and negative predictive value, counterbalanced by low specificity and limited positive predictive value.

Conclusions

Troponin I positivity should be combined with history and clinical evaluation and cautiously interpreted in the ED, especially in patients exhibiting factors associated with higher troponin I levels such as older age, elevated heart rate or ECG changes.Key words: troponin I, acute coronary syndrome, emergency service, hospital, chest pain  相似文献   
73.
Current undergraduate medical curricula provides relatively little time for cadaver dissection. The Department of Human Anatomy and Physiology at the University of Padova has organized a pilot project with the University Hospital for the donation of body parts that are surgically removed for therapeutic purposes and destined under Italian law for destruction. The aim of the project is to improve residents' practical training skills. A survey over the last two years has shown that about 60 body parts were available each year. These included 13 upper limbs or their parts (i.e., forearm with hand, hand, and fingers) and 47 lower limbs or their parts (i.e., legs with feet, feet, or toes). The residents explained the aim of the project to potential donors, and, if patients were willing to donate, their informed consent was obtained. The residents were present in the operating theater during the surgical procedure. In the post-operative phase, the same residents performed dissections on the body part(s), following a teaching schedule prepared by a clinical anatomist, who also assisted residents during their studies. Residents also acted as tutors for undergraduate medical students who attended these dissections. The underlying pathology for which the body part was removed was examined, and surgical procedures were practiced on the body part itself. Our project provided an opportunity for a close relationship between anatomists and surgeons, reinforcing core knowledge of anatomy by appreciation of its clinical importance. The active involvement of residents as learners and as teachers in the various steps of this project improved their knowledge of surgical techniques and helped to establish a sense of ethical responsibility and respect for the human body. This approach involves study of anatomical structures from new perspectives and leads to improved surgical practice.  相似文献   
74.
研究了乙酸仲丁酯汽油(SBAC汽油)对氟、硅、氢化丁腈、丁腈、三元乙丙五种橡胶的溶胀作用和撕裂强度影响。研究表明,氟橡胶对低配比的SBAC汽油有较好的耐油性。当SBAC体积分数不大于10%时,50 d内5种橡胶的厚径变化率是△h氟〈4%、2%〈△h丁腈〈6%、7%〈△h氢化丁腈〈13%、30%〈△h硅、△h三元乙丙〈46%;五种橡胶的撕裂强度都显著降低,撕裂强度变化率在-90%--30%之间。因此发动机的橡胶密封圈最好选用氟橡胶,且SBAC汽油的配比以SBAC体积分数不大于6%为宜。  相似文献   
75.
76.
We developed a cultural self-efficacy scale for adolescents (CSES-A) and tested its psychometric properties using both exploratory and confirmatory factor analyses. Cultural self-efficacy (CSE) was defined as person's perception of his/her own capability to function effectively in situations characterized by cultural diversity. On the basis of Bandura's guideline for the development of a domain-specific self-efficacy measure, we tailored 50 items after reviewing literature about cultural competence, adolescents’ school-problems and social self-efficacy scales developed in previous studies in intercultural contexts. After pre-testing and analyzing psychometric properties of the scale, we selected 33 items. Eight hundred sixty-eight adolescents with five different cultural origins completed a set of questionnaires, including the CSES-A, internal control expectancies, general self-efficacy, academic expectancies, number of people from diverse cultures they keep in touch with, acculturation attitudes, perceived enrichment of other cultures, acculturation stress and demographic data. An EFA with MPLUS 2.14 highlighted a five-factor solution with 25 items that was supported by a subsequent CFA. The five factors were: self-efficacy in mixing satisfactorily with other cultures, in understanding different ways of life, in processing information from other cultures, in coping with loneliness and in learning and understanding other languages. The pattern of correlation with internal control expectancies, general self-efficacy and cultural variables supported the validity of the scale. CSES-A may be useful for future research on multicultural contexts, in which self-efficacy in cultural adaptation could be a fundamental variable.  相似文献   
77.
This article considers the challenges of using artificial intelligence (AI) and machine learning (ML) to assist high-stakes standardised assessment. It focuses on the detrimental effect that even state-of-the-art AI and ML systems could have on the validity of national exams of secondary education, and how lower validity would negatively affect trust in the system. To reach this conclusion, three unresolved issues in AI (unreliability, low explainability and bias) are addressed, to show how each of them would compromise the interpretations and uses of exam results (i.e., exam validity). Furthermore, the article relates validity to trust, and specifically to the ABI+ model of trust. Evidence gathered as part of exam validation supports each of the four trust-enabling components of the ABI+ model (ability, benevolence, integrity and predictability). It is argued, therefore, that the three AI barriers to exam validity limit the extent to which an AI-assisted exam system could be trusted. The article suggests that addressing the issues of AI unreliability, low explainability and bias should be sufficient to put AI-assisted exams on par with traditional ones, but might not go as far as fully reassure the public. To achieve this, it is argued that changes to the quality assurance mechanisms of the exam system will be required. This may involve, for example, integrating principled AI frameworks in assessment policy and regulation.  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