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991.
In this mixed methods study, we employed thematic analysis (TA) to examine peer mentors’ perceptions of benefits, challenges, and roles they experienced as mentors, as well as benefits and challenges experienced by first-year college students. We also utilized quantitative student ratings to classify mentors as highly, moderately, or minimally supportive in order to determine whether any subthemes from the TA appeared more or less frequently across the three groups. Highly supportive mentors reported greater camaraderie among their seminar students and fewer unmotivated students, but also fewer opportunities to provide support to students. Moreover, mentors’ and students’ perceptions in the minimally supportive group were discrepant; mentors in this group consistently reported providing more support than was perceived by mentees.  相似文献   
992.

Past research on deception success has focused on receiver judgments, ignoring deceiver perceptions, which may influence the ways deceivers choose to behave in interpersonal interactions. The present study investigated how several preinteractional and interactional factors affect both deceiver and observer perceptions of deception success. Preinteractional factors included three that have been found relevant to deceptive communication: social skill, self‐monitoring, and motivation. Interactional factors included receiver suspicion, plus four proposed by the four‐factor theory of deception (anxiety, affect, task difficulty, and behavioral control). Results indicated that deceivers’ perceptions of success were more affected by interactional factors (especially anxiety, interaction difficulty, and conversational normality). Conversely, observers were more affected by preinteractional factors such as deceiver social skill. However, motivation, self‐monitoring, and conversational normality affected both deceivers’ and observers’ assessments: greater motivation and self‐monitoring, coupled with more natural, expected communication, yielded greater believability in deceivers’ own eyes and the eyes of observers.  相似文献   
993.
Computational design optimization for microfluidic magnetophoresis   总被引:2,自引:0,他引:2  
Current macro- and microfluidic approaches for the isolation of mammalian cells are limited in both efficiency and purity. In order to design a robust platform for the enumeration of a target cell population, high collection efficiencies are required. Additionally, the ability to isolate pure populations with minimal biological perturbation and efficient off-chip recovery will enable subcellular analyses of these cells for applications in personalized medicine. Here, a rational design approach for a simple and efficient device that isolates target cell populations via magnetic tagging is presented. In this work, two magnetophoretic microfluidic device designs are described, with optimized dimensions and operating conditions determined from a force balance equation that considers two dominant and opposing driving forces exerted on a magnetic-particle-tagged cell, namely, magnetic and viscous drag. Quantitative design criteria for an electromagnetic field displacement-based approach are presented, wherein target cells labeled with commercial magnetic microparticles flowing in a central sample stream are shifted laterally into a collection stream. Furthermore, the final device design is constrained to fit on standard rectangular glass coverslip (60 (L)×24 (W)×0.15 (H) mm3) to accommodate small sample volume and point-of-care design considerations. The anticipated performance of the device is examined via a parametric analysis of several key variables within the model. It is observed that minimal currents (<500 mA) are required to generate magnetic fields sufficient to separate cells from the sample streams flowing at rate as high as 7 ml∕h, comparable to the performance of current state-of-the-art magnet-activated cell sorting systems currently used in clinical settings. Experimental validation of the presented model illustrates that a device designed according to the derived rational optimization can effectively isolate (∼100%) a magnetic-particle-tagged cell population from a homogeneous suspension even in a low abundance. Overall, this design analysis provides a rational basis to select the operating conditions, including chamber and wire geometry, flow rates, and applied currents, for a magnetic-microfluidic cell separation device.  相似文献   
994.
This study examined whether appraisals of 45th U.S. President Donald J. Trump by 1433 adolescents (Mage = 16.1, SDage = 1.16, Female = 56.9%, Latinx = 43.6%, White = 35.7%, Black = 12.6%, Asian = 5.8%) predicted change from 2017 to 2018 across four dimensions of sociopolitical development (SPD): marginalization, critical analysis, civic efficacy, and political action. Trump supporters declined in awareness of inequality and race consciousness but increased in voting intentions. Trump detractors increased in awareness of inequality, race consciousness, and experiences of discrimination. Trump supporters and detractors increased in civic efficacy compared to youth with no opinion. Additional findings were moderated by race and ethnicity. Findings suggest adolescents’ SPD has been shaped in distinct ways by the Trump era.  相似文献   
995.
This article reports on a survey of 332 Year 3 students from 14 Australian schools. We are interested in exploring Year 3 primary school student aspirations and what this data shows us about any societal changes, or not. This study is timely as it reports on contemporary data within an Australian educational context marked by significant investment in improving equitable gendered participation, particularly for girls entering STEM. Drawing on conceptions of masculinities and femininities as social constructions, we report on the participants’ desired occupations and explore their justifications for such choices. The top three occupations for boys included careers in professional sports, STEM-related jobs and policing/defence. Girls reported wanting to be teachers, veterinarians or to work in the arts as their top choices. As part of our exploration, we found issues of money and power—traditionally coded masculine—and conceptions of love and care—traditionally coded feminine—ingrained in boys’ and girls’ justifications for their desired trajectories. Findings are significant for illustrating how traditional constructions of gender are ingrained in career choices in the early years of primary school and how policy agendas to widen participation need to start early in life.  相似文献   
996.
Due to the Covid-19 pandemic, the start of the academic year in September 2020 was a unique time for those transitioning to a new school. This study aimed to explore the experiences of parents who supported autistic children making a range of different school transitions in 2020. Semi-structured interviews were carried out with 13 parents of autistic children in the UK, and data were analyzed with reflexive thematic analysis. For some parents, the Covid-19 pandemic negatively impacted on aspects of school transitions. However, other parents expressed the view that these same circumstances created opportunities to approach the school transition in a unique, improved manner. This article sheds light on the heterogeneity of experiences and perceptions of parents of autistic children, and highlights the need to examine the impact of Covid-19 on school transitions, including practices that it may be advantageous to retain.  相似文献   
997.
Highly skilled return migrants contribute to the establishment of ties between the home and host systems. This paper studies how the professional ties, which Argentinean researchers built up during the time spent in foreign research systems, influence their collaboration patterns and their research outputs upon return. It confirms the expectation that having foreign work experience helps to explain the propensity to co-publish internationally and it also shows that researchers collaborate to a higher degree with their former host system. Another central finding is that foreign work experience has a positive effect on the propensity to publish in journals with a high impact factor. Additionally, a large share of this type of research is published without international co-authorship. We therefore do no not find evidence of a lack of publication autonomy in the case of Argentinean returnees.  相似文献   
998.
Abstract

Competitive sport has been under increasing discussion as a possible favourable factor in the development of eating disorders among children and adolescents. The aim of this study was to determine the frequency of sport-specific eating disorders, in line with the concept of anorexia athletica. This prospective field study included one experimental group and two control groups (disease and healthy). Fifty-two pre-professional ballet dancers aged 13–20 years were tested for clinical eating disorders, anorexia athletica criteria, eating disorder related psychopathology and self-concept, and were compared with 52 patients with anorexia nervosa and 44 non-athletic controls of the same age. The study was conducted using semi-structured interviews as well as self-report questionnaires. A clinical eating disorder diagnosis was made in 1.9% of the ballet dancers versus 0% of the high school students; anorexia athletica was diagnosed in 5.8% of the dancers versus 2.3% of the students. Ballet dancers scored lower than patients with anorexia nervosa with regard to eating disorder related psychopathology and higher than the patients with regard to self-concept. We conclude that more sensitive tools to differentiate between sport-specific (eating) patterns, anorexia athletica and clinically relevant eating disorders are needed, especially for aesthetic sports such as ballet. It remains an important goal to identify athletes with symptoms of anorexia athletica irrespective of their physique and/or sport.  相似文献   
999.
ABSTRACT

The aim of this study was to evaluate the effects of sleep hygiene (SH) education on sleep quality in soccer players after a late-evening small-sided-game (SSG) training session. Twenty-nine non-professional players were recruited and allocated to either an experimental group (EG, n = 17) that received SH education, or a control group (CG, n = 12). SSG consisted of 3 × 4 min in a 4vs4, with 3 min of recovery and was performed at 8.00 p.m. Sleep quality was monitored via actigraphy and sleep diary entries before (PRE) and two nights after (POST1, POST2) the SSG. Sleep latency (SL) differed between the two groups at POST1 (4.9 ± 5.4 vs. 15.5 ± 16.1 for EG and CG, respectively; p = 0.017, effect size [ES] = 2.0); SL values were lower at POST1 compared to PRE for the EG (?47%; p = 0.021, ES = 0.6). Subjective sleep quality was better in the EG than the CG at POST1 (8.6 ± 1.0 vs. 7.1 ± 2.0 for EG and CG, respectively; p = 0.016, ES = 0.9) with a significant improvement over PRE-values (+11.0%, p = 0.004, ES = 0.8). Although SL and subjective sleep quality did not decrease significantly from POST1 to POST2 values at POST2 no longer differed significantly form baseline and, hence, indicate that observed effects may be short-lasting. No other objective sleep indices were influenced by late-evening training or SH practices implemented by the EG. Soccer players may benefit from acute SH strategies to reduce the time to sleep onset after late-evening training sessions.  相似文献   
1000.
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