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981.
Career and educational opportunities in food science and food safety are underrecognized by K‐12 students and educators. Additionally, misperceptions regarding nature of science understanding persist in K‐12 students despite being emphasized as an important component of science education for over 100 y. In an effort to increase awareness concerning career and educational opportunities in food science and food safety and to improve the nature of science understanding among K‐12 students, a series of problem‐based learning modules was developed and pilot tested with a total of 61 K‐12 students. Results of pre‐ and postevaluations and assessments indicated that (1) interest in science, food science, and food safety increased and (2) content knowledge related to the nature of science, food science, and food safety was improved. We further suggest that these modules provide opportunities for educators in traditional as well as extracurricular settings to demonstrate important concepts contained in the newly released Next Generation Science Standards.  相似文献   
982.
Both scientists and policy-makers emphasize the importance of education for influencing pro-environmental behavior and minimizing the effects of climate change on biological and physical systems. Education has the potential to impact students’ system knowledge – their understanding of the variables that affect the climate system – and action knowledge – their understanding of behaviors that can impact the system. Research on climate change education has largely focused on system and action knowledge that address mitigation while overlooking equally necessary adaptive responses. This study used a pre/post-test format to identify aspects of middle and high school students’ climate system knowledge and action knowledge of both mitigation of and adaptation to climate change. Results indicate that adolescents currently conflate climate change mitigation strategies with unrelated environmental problems far less than in previous surveys. However, students demonstrated limited understanding of adaptive responses to climate change. After engaging in an instructional unit on climate change, students expressed stronger system and action knowledge, but significant misconceptions remained that conflated mitigation of and adaptation to climate change.  相似文献   
983.
984.
Companies and other organizations should not underestimate the severity of threats to their information. Small companies and organizations expose themselves to risk in believing that their data are not of interest to cybercriminals. Information security is not just a technical issue, given that technology interventions alone will not provide adequate solutions to the information security needs and challenges of organizations. Because of this, organizations should approach information security in a systematic way. Organizations should implement interventions that supplement technical interventions and provide a systemic plan of action to protect themselves against threats to information security. This article provides an overview of these types of interventions that have been established in the literature.  相似文献   
985.
Gay‐straight alliances (GSAs) may promote resilience. Yet, what GSA components predict well‐being? Among 146 youth and advisors in 13 GSAs (58% lesbian, gay, bisexual, or questioning; 64% White; 38% received free/reduced‐cost lunch), student (demographics, victimization, attendance frequency, leadership, support, control), advisor (years served, training, control), and contextual factors (overall support or advocacy, outside support for the GSA) that predicted purpose, mastery, and self‐esteem were tested. In multilevel models, GSA support predicted all outcomes. Racial/ethnic minority youth reported greater well‐being, yet lower support. Youth in GSAs whose advisors served longer and perceived more control and were in more supportive school contexts reported healthier outcomes. GSA advocacy also predicted purpose. Ethnographic notes elucidated complex associations and variability as to how GSAs operated.  相似文献   
986.
Institutional cultures of assessment are praised as beneficial to student learning. Yet, extant studies have not explored the theoretical foundations and pragmatic approaches to shaping cultures of assessment. The researchers used the Delphi method to explore 10 higher education assessment leaders’ attitudes and theoretical perspectives regarding cultures of assessment. These expert assessment leaders were iteratively surveyed until a reasonable threshold of consensus was reached. Study participants viewed buy-in as a necessary component of a positive campus culture of assessment, and advice on reshaping negative cultures was offered. Assessment leaders’ guiding theoretical frameworks were implied and loosely defined with metaphors. Finally, advice is offered for improving cultures of assessment by symbolically connecting assessment to student learning through dialogue.  相似文献   
987.
The current study examined bidirectional, longitudinal links between prosocial and problem behavior. Participants (= 500) were recruited from a Northwestern city in the United States and assessed for 3 consecutive years from 2009 to 2011 (Mage of youth at Time 1 = 13.32, SD = 1.05; 52% girls; 67% European American, 33% single‐parent families). Results suggested that effects of earlier prosocial behavior toward family and strangers were predictive of fewer problem behaviors 2 years later, while results for prosocial behavior toward friends were more mixed. Results also suggested depression predicted lower prosocial behavior toward family members and anxiety predicted higher prosocial behavior toward friends. Findings show a complex pattern of relations that demonstrate the need to consider targets of helping.  相似文献   
988.
Because body mass change (ΔMb) does not represent all water losses and gains, the present field investigation determined if (a) ΔMb equalled the net effective body water change during ultra-endurance exercise and (b) ground speed and exercise duration influenced these variables. Thirty-two male cyclists (age range, 35–52 years) completed a 164-km event in a hot environment, were retrospectively triplet matched and placed into one of three groups based on exercise duration (4.8, 6.3, 9.6 h). Net effective body water loss was computed from measurements (body mass, total fluid intake and urine excreted) and calculations (water evolved and mass loss due to substrate oxidation, solid food mass and sweat loss), including (ΔEBWgly) and excluding (ΔEBW) water bound to glycogen. With all cyclists combined, the mean ΔMb (i.e. loss) was greater than that of ΔEBWgly by 1200 ± 200 g (P = 1.4 × 10–18), was similar to ΔEBW (difference, 0 ± 200 g; P = .21) and was strongly correlated with both (R2 = .98). Analysis of equivalence indicated that ΔMb was not equivalent to ΔEBWgly, but was equivalent to ΔEBW. Due to measurement complexity, we concluded that (a) athletes will not calculate the effective body water calculations routinely and (b) body mass change remains a useful field-expedient estimate of net effective body water change.  相似文献   
989.
This study investigated whether repeated, very short duration sprints influenced endothelial function (indicated by flow-mediated dilation) and triacylglycerol concentrations following the ingestion of high-fat meals in adolescent boys. Nine adolescent boys completed two, 2-day main trials (control and exercise), in a counter-balanced, cross-over design. Participants were inactive on day 1 of the control trial but completed 40 × 6 s maximal cycle sprints on day 1 of the exercise trial. On day 2, capillary blood samples were collected and flow-mediated dilation measured prior to, and following, ingestion of a high-fat breakfast and lunch. Fasting flow-mediated dilation and plasma triacylglycerol concentration were similar in the control and exercise trial (> 0.05). In the control trial, flow-mediated dilation was reduced by 20% and 27% following the high-fat breakfast and lunch; following exercise these reductions were negated (main effect trial, < 0.05; interaction effect trial × time, < 0.05). The total area under the plasma triacylglycerol concentration versus time curve was 13% lower on day 2 in the exercise trial compared to the control trial (8.65 (0.97) vs. 9.92 (1.16) mmol · l?1 · 6.5 h, < 0.05). These results demonstrate that repeated 6 s maximal cycle sprints can have beneficial effects on postprandial endothelial function and triacylglycerol concentrations in adolescent boys.  相似文献   
990.
The influence of a 12-week-proprioceptive training on functional ankle stability was investigated in young speed skaters. Twenty-eight speed skaters were randomly divided into an intervention (n = 14) and into a control group (n = 14). A 15-min circle training was performed 5 times per week over a 12-week period. Measurements were taken prior to the training, after 6 and 12 weeks of training. Kinaesthesia was evaluated with the Isomed2000 in all movements of the ankle joint. Dynamic balance was tested with the Biodex Stability System at the stable level 8 and at the unstable level 2, measuring the overall stability index, the anterior/posterior and the medial/lateral scores. Static single-leg stance was evaluated using the Kistler force platform. Kinaesthesia of the intervention group improved significantly for plantarflexion of the right foot (P = 0.001) after 12 weeks. Dynamic balance showed significant differences in the intervention group after 12 weeks in comparison with the first measurement for each foot in the overall stability index, the anterior/posterior and the medial/lateral scores (P ≤ 0.017, respectively) at the unstable level 2. Functional ankle stability improved in terms of dynamic balance after 12 weeks of proprioceptive training. Therefore, inclusion of proprioceptive exercises in the daily training programme is recommended for young speed skaters.  相似文献   
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