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   1701篇
  免费   31篇
  国内免费   4篇
教育   1294篇
科学研究   114篇
各国文化   29篇
体育   134篇
综合类   5篇
文化理论   45篇
信息传播   115篇
  2023年   17篇
  2022年   29篇
  2021年   51篇
  2020年   68篇
  2019年   104篇
  2018年   117篇
  2017年   122篇
  2016年   105篇
  2015年   70篇
  2014年   94篇
  2013年   332篇
  2012年   111篇
  2011年   66篇
  2010年   45篇
  2009年   53篇
  2008年   43篇
  2007年   39篇
  2006年   28篇
  2005年   31篇
  2004年   28篇
  2003年   22篇
  2002年   36篇
  2001年   10篇
  2000年   14篇
  1999年   4篇
  1998年   11篇
  1997年   6篇
  1996年   6篇
  1995年   6篇
  1994年   7篇
  1993年   4篇
  1992年   8篇
  1991年   5篇
  1990年   8篇
  1989年   6篇
  1988年   3篇
  1987年   1篇
  1985年   1篇
  1983年   3篇
  1982年   1篇
  1981年   2篇
  1980年   4篇
  1979年   4篇
  1978年   3篇
  1977年   4篇
  1973年   1篇
  1964年   1篇
  1963年   2篇
排序方式: 共有1736条查询结果,搜索用时 31 毫秒
71.

Introduction:

Additional nucleotide substitutions in the 3′-untranslated region of prothrombin gene could explain some thrombotic events and also adverse pregnancy outcomes. We describe the first case of a homozygous 20209C>T mutation as the cause of deep vein thrombosis in a Spanish patient.

Case and methods:

The 56-year-old male patient with a partial tear of the Achilles tendon developed calf (tibial) deep vein thrombosis after immobilization and was treated with an anticoagulant. To determine if the deep vein thrombosis was of genetic origin, a peripheral blood DNA sample was analysed for the presence of the three most frequent mutations associated with thrombotic events: factor V Leiden (1691G>A), prothrombin (20210G>A) and methylene tetrahydrofolate reductase (677C>T). The presence or absence of the normal allele of prothrombin could not be determined using the PTH-FV-MTHFR StripAssay (Vienna Lab).

Results:

Comprehensive analysis showed that the patient had a variant interfering with the polymerase chain reaction product, we sequenced the entire prothrombin gene and found that the patient had a homozygous C>T mutation at position 20209; this interfered with the polymerase chain reaction product, which needs a C at this position to be able to bind to the wild-type probe present in the test strip.

Conclusion:

The homozygous 20209C>T mutation and the presence of the mutation 677C>T in heterozygosity explained the patient’s deep vein thrombosis because the combination of mutations would increase the risk of thrombosis. Suitable genetic counselling should be provided to the patient and first-degree relatives as it important to detect prothrombin gene variants that could increase risk for thrombotic events.  相似文献   
72.
BackgroundDespite the well-established health benefits of physical activity (PA) for young people (aged 4–19 years), most do not meet PA guidelines. Policies that support PA in schools may be promising, but their impact on PA behavior is poorly understood. The aim of this systematic review was to ascertain the level and type of evidence reported in the international scientific literature for policies within the school setting that contribute directly or indirectly to increasing PA.MethodsThis systematic review is compliant with Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Six databases were searched using key concepts of policy, school, evaluation, and PA. Following title and abstract screening of 2323 studies, 25 progressed to data synthesis. Methodological quality was assessed using standardized tools, and the strength of the evidence of policy impact was described based on pre-determined codes: positive, negative, inconclusive, or untested statistically.ResultsEvidence emerged for 9 policy areas that had a direct or indirect effect on PA within the school setting. These were whole school PA policy, physical education, sport/extracurricular PA, classroom-based PA, active breaks/recess, physical environment, shared use agreements, active school transport, and surveillance. The bulk of the evidence was significantly positive (54%), 27% was inconclusive, 9% was significantly negative, and 11% was untested (due to rounding, some numbers add to 99% or 101%). Frequency of evidence was highest in the primary setting (41%), 34% in the secondary setting, and 24% in primary/secondary combined school settings. By policy area, frequency of evidence was highest for sport/extracurricular PA (35%), 17% for physical education, and 12% for whole school PA policy, with evidence for shared use agreements between schools and local communities rarely reported (2%). Comparing relative strength of evidence, the evidence for shared use agreements, though sparse, was 100% positive, while 60% of the evidence for whole school PA policy, 59% of the evidence for sport/extracurricular PA, 57% of the evidence for physical education, 50% of the evidence for PA in classroom, and 50% of the evidence for active breaks/recess were positive.ConclusionThe current evidence base supports the effectiveness of PA policy actions within the school setting but cautions against a “one-size-fits-all” approach and emphasizes the need to examine policy implementation to maximize translation into practice. Greater clarity regarding terminology, measurement, and methods for evaluation of policy interventions is needed.  相似文献   
73.
To determine the effect of circadian rhythm on neuromuscular responses and kinematics related to physical tennis performance, after a standardised warm-up, 13 highly competitive male tennis players were tested twice for serve velocity/accuracy (SVA), countermovement vertical jump (CMJ), isometric handgrip strength (IS), agility T-test (AGIL) and a 10-m sprint (10-m RUN). In a randomised, counter-balance order, tennis players underwent the test battery twice, either in the morning (i.e., AM; 9:00 h) and in the afternoon (i.e., PM; 16:30 h). Paired t-tests were used to analyse differences due to time-of-day in performance variables. Comparison of morning versus afternoon testing revealed that SVA (168.5 ± 6.5 vs. 175.2 ± 6.1 km · h?1; P = 0.003; effect size [ES] = 1.07), CMJ (32.2 ± 0.9 vs. 33.7 ± 1.1 cm; P = 0.018; ES = 1.46), AGIL (10.14 ± 0.1 vs. 9.91 ± 0.2 s; P = 0.007; ES = 1.23) and 10-m RUN time (1.74 ± 0.1 vs. 1.69 ± 0.1 s; P = 0.021; ES = 0.67) were significantly blunted during the morning testing. However, IS was not affected by time-of-day (P = 0.891). Thus, tennis performance may be reduced when competing in the morning in comparison to early evening. Therefore, coaches and tennis players should focus on schedule the SVA, power, speed and agility training sessions in the afternoon.  相似文献   
74.
This study aimed to identify the maturity-related differences and its influence on the physical fitness, morphological and performance characteristics of young elite paddlers. In total, 89 kayakers and 82 canoeists, aged 13.69 ± 0.57 years (mean ± s), were allocated in three groups depending on their age relative to the age at peak height velocity (pre-APHV, circum-APHV and post-APHV) and discipline (kayak and canoe). Nine anthropometric variables, a battery of four physical fitness tests (overhead medicine ball throw, countermovement jump, sit-and-reach test and 20 m multistage shuttle run test) and three specific performance tests (1000, 500 and 200 m) were assessed. Both disciplines presented significant maturity-based differences in all anthropometric parameters (except for fat and muscle mass percentage), overhead medicine ball throw and all performance times (pre > circum > post; < 0.05). Negative and significant correlations (< 0.01) were detected between performance times, chronological age and anthropometry (body mass, height, sitting height and maturity status), overhead medicine ball throw and sit and reach for all distances. These findings confirm the importance of maturity status in sprint kayaking and canoeing since the more mature paddlers were also those who revealed largest body size, physical fitness level and best paddling performance. Additionally, the most important variables predicting performance times in kayaking and canoeing were maturity status and chronological age, respectively.  相似文献   
75.
This article makes an explicit comparison between the reconfiguration of tertiary language education in Europe, the USA and Canada. It argues that, despite certain minor differences between continents, the same trends are operative across the Atlantic. It then examines each of them, illustrating how similar forces are at work in shaping higher education language teaching, how analogous policy frameworks are being employed to channel them and how parallel challenges and responses can be detected transatlantically. The conclusion is that unifying efforts and connecting initiatives has highly beneficial effects for advancing the application of higher education language policy worldwide.  相似文献   
76.
77.
观察了大运动量训练期8名自由式摔跤运动员应激激素、焦虑水平及主观强度感的变化。研究过程中,每周安排11次大运动量训练,共进行2次实验,每次3个取样点(运动前、即刻和次日晨)。结果显示,两次取样时期次日晨ACTH水平较运动后即刻明显降低;C水平在第二次取样运动后即刻水平和次日晨水平明显高于运动前的,并且该时期运动后即刻C水平也明显高于第一次取样时期运动后即刻水平;E水平在第二次取样运动后即刻水平明显高于第一次取样运动后即刻的,且次日晨该激素水平也明显高于第一次取样次日晨的;血浆β-END水平在第二次取样运动后即刻水平明显高于运动前,也高于第一次取样运动后即刻,第二次取样次日晨该激素水平均低于运动前和运动后即刻水平,同时低于第一次取样次日晨的;血清NE水平变化与β-END水平变化类似;而RPE等级和焦虑水平在两次测试中呈现出运动后即刻水平高于运动前和次日晨的趋势,但不明显;RPE等级与诸多应激激素之间存在着弱相关关系。这预示着,在运动员身体机能评定工作中欲采用简单易行的显示身体机能的外部指标来表现不易测到的内部变化还需努力。  相似文献   
78.
The objective of this study was to assess the relationship between the institutionalization of a dependent elderly relative and the family caregiver’s mental health, quality of life and caregiving satisfaction. We present data from 140 family caregivers caring for elderly family members, of whom 77 continued to live with family members and 63 had been institutionalized. We evaluated the factors influencing the decision to institutionalize the dependent relative, the effect of institutionalization on the caregiver’s psychological well-being and quality of life and the impact of strategies to find the meaning and cope with the relative’s placement on the caregiver’s emotional health and quality of life. Care does not end after institutionalization, but the stressors the caregiver faces change. Our results suggest that finding meaning increases satisfaction and reduces feelings of overload. They show that after institutionalization, stressors affecting caregivers are partly relieved, and that finding meaning increases the caregiver’s satisfaction, while decreasing the degree of overload. Our data, further, indicates that a good relationship and cooperation between the staff of the institution and the family are important to improve the caregivers’ emotional health and quality of life, and consequently, the quality of life of the dependent elderly relative.  相似文献   
79.
The prevailing pedagogical orientations of English as a foreign language (EFL) education in Spain oppress learners intellectually in ways that are counterproductive to their learning. As a reaction to this, 129 EFL student-teachers (STs) took part during the 2013/14, 2014/15, and 2015/16 academic years in a workshop which drew on the methodology of participatory action research and on photovoice as a data-creating strategy, in order to emancipate these STs intellectually, boost their EFL development, and offer an alternative critical model for their future EFL teaching. The research was assessed collectively through a variety of qualitative strategies. Results showed that the photovoice workshop created a rich and meaningful context for EFL learning, one which enabled the STs to fully actualize their intellectual potential by producing knowledge collectively, thereby setting a memorable educational example for their own future teaching.  相似文献   
80.
European Journal of Psychology of Education - This work analyzes the possible existence of self-protection profiles based on a combination of self-handicapping (behavioral and claimed) strategies...  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