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101.
102.
In this paper,we prove that the Veronese surface can be determined by the 1-spectrum of the Laplace operator. 相似文献
103.
The present research examined the role of maladaptive self-regulatory beliefs as vulnerability factors for academic and emotional difficulties during the transition to middle school. A short-term longitudinal design was employed to follow two groups of early adolescents: 187 adolescents who experienced a school transition between the fifth and sixth grades, and 142 adolescents who did not experience a school transition between the fifth and sixth grades. Adolescents completed measures of perceptions of academic control and importance of academic success, experience of chronic academic strain, daily school hassles, and depressive symptoms. Teachers reported on students' academic engagement, including levels of helpless behavior, effort, and academic performance. Consistent with the proposed model of self-regulation, maladaptive self-regulatory beliefs (i.e., decreased perceptions of academic control and importance) predicted individual differences in perceived school-related stress and depressive symptoms over the course of the middle school transition, but were not associated with academic and emotional difficulties in adolescents who remained in a stable school environment. Moreover, a self-regulatory sequence was identified proceeding from maladaptive self-regulatory beliefs, to academic disengagement, to enhanced perceptions of school-related stress, to depressive symptoms. This study bridges prior theory and research concerning the psychological impact of normative developmental transitions, the developmental context of depression, and the associations among self-regulatory beliefs, achievement-related behavior, and emotional experience. 相似文献
104.
OBJECTIVE: A model was examined in which the association between a parent's history of abuse and the parent's own abusive behavior toward his or her children was hypothesized to be mediated by parental psychopathology, early childbearing, and consistency of discipline. Additionally, the effect of severity of abuse on the likelihood of becoming abusive was examined. METHOD: Participants were 109 parents (G1) and their male children (G2) who were involved in a longitudinal study. The G1 parents reported on their own experiences of abuse when they were children. Ten years later, the G2 youths reported on the G1 parents' abusive behavior toward them. A number of other factors, including parental socioeconomic status (SES), antisocial behavior, depression and Post-traumatic Stress Disorder (PTSD), consistency of discipline, and the perceived early difficulty of the G2 children were measured. RESULTS: As reported by their own children, parents who reported having been abused in childhood were significantly more likely to engage in abusive behaviors toward the next generation. Findings indicated that abuse experienced by the parents, as well as consistency of discipline and depression plus PTSD, were predictive of parental abuse of the child. Contrary to hypotheses, the effects were not fully mediated. However, there were significant interactions between parental history of abuse and consistency of discipline, as well as abuse history and depression and PTSD. Parents who had experienced multiple acts of abuse and at least one physical impact were more likely to become abusive than were the other parents. CONCLUSIONS: The implications of these findings for preventive interventions are discussed. 相似文献
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107.
Cultural Studies of Science Education - Over the last few decades, there has been an international focus on productive talk in science classrooms, requiring teachers to use more dialogic practices... 相似文献
108.
Joe D. Nichols 《Learning Environments Research》2006,9(2):149-161
This project focused on the goal of establishing a classroom model of motivation in which the source of student motivation is based on internal mechanisms or structures, along with the establishment of greater self-regulatory opportunities for students, and which results in greater student empowerment and motivation. One-hundred current elementary and secondary teachers and 100 university preservice teacher education students completed a 40-item Likert-type questionnaire that focused on four classroom dimensions of affirmation, rejection, student empowerment and teacher control. The results of this project suggested that, although veteran and preservice teachers agreed on the need for teacher control in the classroom, there was less agreement about their perceptions of the need to create a classroom environment of positive affirmation and student empowerment. Implications for future research and the need for creating an affirming, empowering, motivational classroom environment are discussed in light of the limitations for teachers and schools to encourage these constructs associated with recent federal legislative policies. 相似文献
109.
Olson RK 《Annals of dyslexia》2006,56(2):205-238
This article presents an overview of some methods and results from our continuing studies of genetic and environmental influences
on dyslexia, and on individual differences across the normal range that have been conducted over the past 25 years in the
Colorado Learning Disabilities Research Center (CLDRC) and in related projects. CLDRC investigators compare the similarities
of identical twin pairs who share all their genes and fraternal twins who share half their segregating genes to assess the
balance of genetic, shared family environment, and nonshared environment influences on dyslexia and on individual differences
across the normal range. We have learned that among the children we have studied in Colorado, group deficits in reading (dyslexia)
and individual differences in reading across the normal range are primarily due to genetic influences, and these genetic influences
are often shared with some of the same genetic influences on deficits and individual differences in language and ADHD. We
have also learned from our molecular-genetic linkage studies that there are regions on several chromosomes likely to contain
genes that influence dyslexia. Several specific genes within these regions have been tentatively identified through molecular-genetic
association analyses, but much more research is needed to understand the pathways among specific genes, regions of noncoding
DNA that regulate the activity of those genes, the brain, and dyslexia. I conclude with a discussion of our research on individual
differences in early reading development, on the role of early learning constraints in dyslexia, and on how genetic influences
are expressed through their interaction and correlation with the environment. 相似文献
110.
Effectiveness of Spanish intervention for first-grade English language learners at risk for reading difficulties 总被引:1,自引:0,他引:1
Vaughn S Linan-Thompson S Mathes PG Cirino PT Carlson CD Pollard-Durodola SD Cardenas-Hagan E Francis DJ 《Journal of learning disabilities》2006,39(1):56-73
The effectiveness of an explicit, systematic reading intervention for first-grade students whose home language was Spanish and who were at risk for reading difficulties was examined. Participants were 69 students in 20 classrooms in 7 schools from 3 districts who initially did not pass the screening in Spanish and were randomly assigned within schools to a treatment or comparison group; after 7 months, 64 students remained in the study. The intervention matched the language of instruction of their core reading program (Spanish). Treatment groups of 3 to 5 students met daily for 50 min and were provided systematic and explicit instruction in oral language and reading by trained bilingual intervention teachers. Comparison students received the school's standard intervention for struggling readers. Observations during core reading instruction provided information about the reading instruction and language use of the teachers. There were no differences between the treatment and comparison groups in either Spanish or English on any measures at pretest, but there were significant posttest differences in favor of the treatment group for the following outcomes in Spanish: Letter-Sound Identification (d = 0.72), Phonological Awareness composite (d = 0.73), Woodcock Language Proficiency Battery-Revised Oral Language composite (d = 0.35), Word Attack (d = 0.85), Passage Comprehension (d = 0.55), and two measures of reading fluency (d = 0.58-0.75). 相似文献