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   458篇
  免费   10篇
教育   359篇
科学研究   23篇
各国文化   5篇
体育   19篇
文化理论   4篇
信息传播   58篇
  2024年   1篇
  2023年   2篇
  2022年   9篇
  2021年   10篇
  2020年   12篇
  2019年   24篇
  2018年   22篇
  2017年   17篇
  2016年   24篇
  2015年   21篇
  2014年   22篇
  2013年   79篇
  2012年   21篇
  2011年   13篇
  2010年   17篇
  2009年   18篇
  2008年   17篇
  2007年   12篇
  2006年   8篇
  2005年   12篇
  2004年   12篇
  2003年   6篇
  2002年   7篇
  2001年   3篇
  2000年   6篇
  1999年   3篇
  1998年   6篇
  1997年   5篇
  1996年   2篇
  1995年   4篇
  1994年   6篇
  1993年   7篇
  1992年   3篇
  1991年   4篇
  1990年   6篇
  1989年   3篇
  1988年   2篇
  1987年   4篇
  1986年   1篇
  1985年   1篇
  1984年   2篇
  1982年   2篇
  1981年   2篇
  1979年   2篇
  1978年   1篇
  1977年   4篇
  1976年   1篇
  1963年   1篇
  1960年   1篇
排序方式: 共有468条查询结果,搜索用时 0 毫秒
461.
Bioelectrical impedance spectroscopy (BIS) is an inexpensive and non-invasive technique to measure total body water (TBW), extracellular water (ECW), and intracellular water (ICW). The purpose of this study was to validate TBW, ECW and ICW assessed by BIS, using dilution techniques as the reference method (REF) in elite judo athletes. Thirty-two Portuguese elite male judo athletes were evaluated during a period of weight stability. TBW, ECW and ICW were assessed by BIS (Xitron 4000). Deuterium and bromide dilution techniques were used as the criterion method for measuring TBW and ECW, while ICW was calculated as the difference between the two. BIS explained 96%, 77% and 94% of the total variability from REFs for TBW, ECW and ICW, respectively. BIS also demonstrated high precision (ρ ≥ 0.88) and accuracy (Cb = 0.98), with a minimum concordance coefficient correlation of 0.87 for ECW. The mean bias demonstrated that BIS slightly overestimated the REF in 1.1 kg (2.3%), 0.3 kg (1.6%) and 0.8 kg (2.7%) for TBW, ECW and ICW, respectively. The 95% limits of agreement ranged from ?1.2 to 3.3 kg in TBW, from ?1.8 to 2.4 kg in ECW and from ?1.0 to 2.6 kg in ICW. A non-significant trend was found between the difference and the mean of reference and alternative methods. These findings highlight the efficacy of BIS as a valid non-biased tool for the assessment of TBW and its compartments in elite male judo athletes, during a period of weight stability.  相似文献   
462.
The aim of this study was to investigate the effectiveness of a caffeine-containing energy drink to enhance physical and match performance in elite badminton players. Sixteen male and elite badminton players (25.4 ± 7.3 year; 71.8 ± 7.9 kg) participated in a double-blind, placebo-controlled and randomised experiment. On two different sessions, badminton players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed the following tests: handgrip maximal force production, smash jump without and with shuttlecock, squat jump, countermovement jump and the agility T-test. Later, a 45-min simulated badminton match was played. Players’ number of impacts and heart rate was measured during the match. The ingestion of the caffeinated energy drink increased squat jump height (34.5 ± 4.7 vs. 36.4 ± 4.3 cm; < 0.05), squat jump peak power (< 0.05), countermovement jump height (37.7 ± 4.5 vs. 39.5 ± 5.1 cm; < 0.05) and countermovement jump peak power (< 0.05). In addition, an increased number of total impacts was found during the badminton match (7395 ± 1594 vs. 7707 ± 2033 impacts; < 0.05). In conclusion, the results show that the use of caffeine-containing energy drink may be an effective nutritional aid to increase jump performance and activity patterns during game in elite badminton players.  相似文献   
463.

Learning to name and notice students’ mathematical strengths is a challenging process requiring time and multiple iterations of practice for prospective teachers (PTs) to adopt. Mathematics teacher educators (MTEs) can approximate and decompose the complex practice of naming and noticing students’ mathematical strengths so PTs learn to teach mathematics while emphasizing what students know and can do. This study uses two tools MTEs can use to support PTs as they learn to name and notice students’ mathematical strengths: A LessonSketch experience, a digital platform with comic-based storyboards showing children engaged in a mathematics task, and a strengths-based sentence frame. Our study presents the findings from the 111 noticing statements from 18 PTs as they engaged in the LessonSketch digital experience and practiced making noticing statements about what children know about mathematics. The study found that after a sentence-frame intervention, the PTs are more likely to use strengths-based language and more likely to identify mathematical evidence in their noticing statements. Uncommitted language (statements that do not align with a strength- or deficit-based coding scheme), suggests a fruitful, yet complex space for supporting more PTs as they learn to name and notice students’ mathematical strengths. The paper concludes with implications for future research in teacher education.

  相似文献   
464.
Mobile geolocation applications identify global coordinates of mobile devices and can be enriched with performance‐context data. This technology has potential to integrate job aids, learning bursts, and parts of manuals with work tools (such as checklists) at the point of performance to better support individual and team performance. Emerging uses of mobile geolocation allow human performance technologists to move from generic electronic performance support systems (EPSSs) to spatial support systems. These increase the potential for performers to access more context‐aware information at the time and space in which the actions occur. Mobile geolocation can also automatically send data about the performance to enterprise databases so that actions taken and the use of training or job aids at the point of performance can be tracked. This article explores how mobile geolocation functionality can be orchestrated to support performance, enrich enterprise databases, and aid human performance technologists.  相似文献   
465.
Teachers are often assumed to have a negative attitude towards quality endeavours of their institutions and to hold defensive organisational values. However, there is little empirical research on this issue. This study focuses on teachers’ conceptions of quality, on their preferred organisational values and on the relationships between the two. A written questionnaire was presented to the teaching staff from 18 departments of universities of applied sciences in the Netherlands (N?=?266). It comprised 18 questions about teachers’ conceptions of quality, representing two quality scales: compliance and accountability and enhancement and improvement. A further 24 questions, related to organisational values, represent two scales that typify flexible organisations, and two that typify control-oriented organisations. The results reveal a neutral score on the compliance and accountability conceptions of quality and on the control-oriented organisational values, and a high score on enhancement and improvement and on the flexibility-oriented values. Both pairs appear to be moderately positively correlated. Despite the need for further qualitative research, it can be concluded that teachers perceive quality first and foremost as enhancement and improvement, rather than as compliance to external standards and accountability. These findings offer interesting perspectives for the further development of an internal quality culture in higher education.  相似文献   
466.
Background: The physical education (PE) context has been emphasised as an ideal environment for developing positive behaviours among students. Under the Positive Youth Development paradigm, various initiatives have been conducted with the aim of promoting personal and social responsibility among adolescents. Self-Determination Theory has been widely used to analyse students’ motivational processes during PE classes.

Purpose: This study aimed to measure the effects of a multidisciplinary intervention with teachers on the development of positive behaviours in PE classes.

Participants: Twenty PE teachers participated in the study (Mage?=?35 years; SD?=?2.32) along with 777 of their students (Mage?=?12.81 years; SD?=?.93). The teachers (male?=?16; female?=?4) were between the ages of 29 and 48 years (M?=?35.2 years; SD?=?2.32). The students who participated in this study (male?=?377; female?=?400) were divided into 52 classes and were between the ages of 12 and 16 years (M?=?12.81; SD?=?.93).

Research design: A quasi-experimental design was used that consisted of a control group and three groups in which an intervention was developed. In the control group, the teachers did not receive any type of intervention; in the second group, the teachers received a training programme to develop strategies for supporting basic psychological needs and promoting positive behaviours; in the third group, the teachers received a didactic unit to promote positive behaviours; and in the last group the teachers received a combination of the two previous interventions.

Data analysis: A repeated-measures ANCOVA (analysis of covariance) was used for every dependent variable included in the study to analyse the effect of Group?×?Time interaction, including Gender and Grade Level as covariates. The fixed effects caused by Intercept, Group, Time, and the Group?×?Time interaction were calculated using compound symmetry as the type of covariance and restricted maximum likelihood as the estimation method.

Findings: By examining the differences between pre-test and post-test, it was determined that in comparison with the students in the control group, the students from the three experimental groups had generally improved scores on the variables related to positive behaviours, such as perceptions of the teacher's support, as well as the development of the targeted behaviours.

Conclusions: These results provide information about the efficacy of an intervention programme with teachers that consists of strategies for developing positive behaviour and support for basic psychological needs to promote the development of positive student behaviour.  相似文献   
467.

Introduction:

Zonulin is a eukaryotic protein structurally similar to Vibrio cholerae’s zonula occludens toxin. It plays an important role in the opening of small intestine tight junctions. The loss of gut wall integrity during sepsis might be pivotal and has been described in various experimental as well as human studies. Increased levels of zonulin could be demonstrated in diseases associated with increased intestinal inflammation, such as celiac disease and type 1 diabetes. We therefore investigated the role of plasma levels of zonulin in patients with sepsis as a non-invasive marker of gut wall integrity.

Materials and methods:

Plasma level of zonulin was measured in 25 patients with sepsis, severe sepsis or septic shock according to ACCP/SCCM criteria at the first day of diagnosed sepsis. 18 non-septic post-surgical ICU-patients and 20 healthy volunteers served as control. Plasma levels were determined by using commercially available ELISA kit. Data are given as median and interquartile range (IQR).

Results:

Significantly higher plasma concentration of zonulin were found in the sepsis group: 6.61 ng/mL (IQR 3.51–9.46), as compared to the to the post-surgical control group: 3.40 ng/mL (IQR 2.14–5.70) (P = 0.025), as well as to the healthy group: 3.55 ng/mL (IQR 3.14–4.14) (P = 0.008).

Conclusion:

We were able demonstrate elevated levels of plasma zonulin, a potential marker of intestinal permeability in septic patients. Increased zonulin may serve as an additional mechanism for the observed increased intestinal permeability during sepsis and SIRS.  相似文献   
468.
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