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781.
Ross A. Thompson 《Child development》1990,61(1):1-16
Assessing potential risks to children who participate in developmental research is a challenging task because children are a heterogeneous population, varying in developmental competencies and in background characteristics. This essay offers a developmental perspective on research risk, emphasizing that children's vulnerability to research risk changes in complex ways: some risks decrease with increasing age, some increase as the child matures, others change in a curvilinear fashion, while some remain essentially stable with development. Because vulnerability in research does not simply decline linearly with age, assessments of research risk must entail multidimensional considerations that vary over developmental time. In a similar manner, individual characteristics of children at any age (e.g., maltreatment, at-risk status, etc.) may also heighten their vulnerability to certain risks which require special consideration by researchers. Finally, this discussion of developmental vulnerability and the principles underlying research ethics suggests that in addition to the conventional risk/benefit analysis, researchers are in an optimal position to establish and maintain standards of decent treatment of children in research that safeguard their rights as research participants. Suggestions for fostering this process in the research community are outlined. 相似文献
782.
Self‐worth protective students characteristically perform well on some occasions yet on other occasions they perform poorly. In this study, two accounts of the poor performance of self‐worth protective students are assessed. The first is that their poor performance is an outcome of evaluative threat. The second is that their poor performance is an outcome of future outcome uncertainty: a product of their uncertain global self‐esteem and uncertainty about the causes of achievement outcomes. Students high or low in self‐worth protection were exposed to either noncontingent success (creating future outcome uncertainty), noncontingent failure (evoking evaluative threat), or contingent success. Their ability to solve two tasks that involved a high degree of uncertainty was then assessed. Students high in self‐worth protection performed poorly following both noncontingent failure and noncontingent success, supporting the roles of both evaluative threat and future outcome uncertainty. The implications in terms of enhancing the achievement of students high in self‐worth protection are discussed. 相似文献
783.
OBJECTIVE: This study had four objectives: 1) to examine the association between sexual victimization and weight regulation across three samples of adolescent girls, 2) to assess whether sexual victimization is associated with more extreme forms of weight regulation in girls, 3) to discern whether sexual victimization has implications for the use of multiple forms of weight regulation, and 4) to address the role of physical victimization in explaining these relationships. METHOD: Data from three separate samples of 9th-12th graders were used to test these hypotheses. Girls from the upper Midwest responded to survey questions related to victimization and weight regulation in a largely urban sample (N = 2,086), a rural sample (N = 2,629), and a statewide sample (N = 966). RESULTS: Logistic regression revealed that sexual victimization was consistently associated with weight regulation in adolescent girls, independent of the effects of physical victimization. In the urban sample, being sexually victimized was associated with an increase in the probability of purging by 18% relative to not being sexually victimized. Sexual victimization was associated more strongly with extreme forms of weight regulation and significantly discriminated whether girls would choose multiple weight regulation forms. CONCLUSIONS: Sexual victimization contributes unique variance to the probability that girls will practice weight regulation techniques. Data from three independent samples confirms that being violated sexually places girls at risk for various health compromising eating behaviors. 相似文献
784.
Infants' affective responses in the strange situation: effects of prematurity and of quality of attachment 总被引:1,自引:0,他引:1
20 full-term and 20 preterm infants and their mothers were videotaped in the Strange Situation, and the security of their attachment relationships was later determined. Each episode was subsequently divided into consecutive 15-sec intervals, during each of which ratings of facial expressions were performed. From these ratings several summary dimensions of affect were derived (e.g., affective peak and range during all episodes, latency and rise time for onset of distress during separation episodes, and recovery time during reunions). Term and preterm infants did not differ from one another in either the security of attachment or their affective expression and regulation. When groups were combined, patterns of affective expression were significantly different for infants classified as insecure-avoidant, insecure-ambivalent, and securely attached, as well as for group B1 + B2 infants compared to group B3 + B4 babies. The findings indicated that attachment-related affect may reflect an affect continuum that underlies certain mother- and stranger-directed behaviors in the Strange Situation, but that not all aspects of reunion behavior can be predicted by prior separation reactions. 相似文献
785.
Marbach-Ad G Briken V Frauwirth K Gao LY Hutcheson SW Joseph SW Mosser D Parent B Shields P Song W Stein DC Swanson K Thompson KV Yuan R Smith AC 《CBE life sciences education》2007,6(2):155-162
As research faculty with expertise in the area of host–pathogen interactions (HPI), we used a research group model to effect our professional development as scientific educators. We have established a working hypothesis: The implementation of a curriculum that forms bridges between our seven HPI courses allows our students to achieve deep and meaningful learning of HPI concepts. Working collaboratively, we identified common learning goals, and we chose two microorganisms to serve as anchors for student learning. We instituted variations of published active-learning methods to engage students in research-oriented learning. In parallel, we are developing an assessment tool. The value of this work is in the development of a teaching model that successfully allowed faculty who already work collaboratively in the research area of HPI to apply a “research group approach” to further scientific teaching initiatives at a research university. We achieved results that could not be accomplished by even the most dedicated instructor working in isolation. 相似文献
786.
This is a design study meant to demonstrate the feasibility of integrating three rather different theoretical perspectives
for future efforts in multimedia instructional design. A multimedia instructional grammar program contextualized within the
teaching of English as a Second Language (ESL) was developed and evaluated. The program design was grounded in Mayer’s multimedia
learning theory (2001), Sweller’s cognitive load theory (CLT, 2005), and cognitive training theory using an inductive reasoning
paradigm (Klauer and Phye, Rev Educ Res 78(1):85–124, 2008). A successful integration of cognitive training theory into program design is expected to facilitate the transition of student’s
declarative knowledge of a grammar concept of passive voice to procedural knowledge (Phye, Contemp Educ Psychol 16:87–94,
1991; Phye et al., Empirical methods for evaluating educational interventions, Academic Press/Elsevier, San Diego, 2005). Two studies involving ten and four adult ESL learners were conducted in a Midwest community college. Grammar teaching occurred
within the context of history and geography of the USA. Students with low prior knowledge of passive voice grammar concepts,
intermediate level of general vocabulary, and adequate basic knowledge of content (basic geography and history) benefited
most from the program. Preliminary results are encouraging for the aforementioned integrative efforts. 相似文献
787.
788.
Genevieve Kate Roscoe Williams Gareth Irwin David George Kerwin Karl Maxim Newell 《Journal of sports sciences》2015,33(13):1376-1387
Biomechanical energetic analysis of technique can be performed to identify limits or constraints to performance outcome at the level of joint work, and to assess the mechanical efficiency of techniques. The aim of this study was to investigate the biomechanical energetic processes during learning the longswing on the high bar. Twelve male, novice participants took part in a training study. Kinematic and kinetics data were collected during swing attempts in eight weekly testing sessions. Inverse dynamics analysis was performed from known zero forces at the toes. Joint work, total energy, and bar energy were calculated. Biomechanical constraints to action, that is, limits to novice performance, were identified as “total work” and “shoulder work”. The most biomechanically efficient technique was associated with an onset of the hip functional phase and joint work that occurred between 10–45° before the bottom of the swing. The learning of gross motor skills is realised through the establishment of a set of techniques with task specific biomechanical constraints. Knowledge of the biomechanical constraints to action associated with more effective and efficient techniques will be useful for both assessing learning and establishing effective learning interventions. 相似文献
789.
Genevieve K.R. Williams Gareth Irwin David G. Kerwin Karl M. Newell 《Journal of sports sciences》2015,33(1):29-38
Biomechanics helps us understand the association between technique changes and performance improvement during learning. The aim of this research was to investigate joint kinetic characteristics of technique during learning of the longswing on the high bar. Twelve male, novice participants took part in the learning study. During swing attempts in 8 weekly testing sessions, kinematic data were collected. Inverse dynamics analysis was performed from known zero forces at the toes to quantify joint moments and power at the hips and shoulders. Key biomechanical constraints that limited performance outcome were identified based on changes in joint kinetics during learning. These constraints were the ability to perform a large shoulder power and to overcome passive kinetics acting during the downswing. Constraints to action at the level of joint kinetics differentially challenge learners and therefore could underpin more individual, specific learning interventions. Functional phases, defined by maximum hyperextension to flexion of the hips and maximum flexion to extension of the shoulders, did not describe the key joint kinetics of the hip and shoulder for novices. The functional phases may serve however to identify novices that were unable to overcome the passive kinetic constraint. 相似文献
790.