全文获取类型
收费全文 | 196篇 |
免费 | 4篇 |
专业分类
教育 | 107篇 |
科学研究 | 20篇 |
体育 | 44篇 |
信息传播 | 29篇 |
出版年
2014年 | 1篇 |
2012年 | 21篇 |
2011年 | 25篇 |
2010年 | 7篇 |
2008年 | 10篇 |
2007年 | 22篇 |
2006年 | 16篇 |
2005年 | 9篇 |
2004年 | 11篇 |
2003年 | 16篇 |
2002年 | 9篇 |
2001年 | 4篇 |
2000年 | 8篇 |
1999年 | 10篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1979年 | 1篇 |
1972年 | 1篇 |
1968年 | 1篇 |
1958年 | 1篇 |
1957年 | 2篇 |
1956年 | 1篇 |
1955年 | 1篇 |
1949年 | 1篇 |
1948年 | 1篇 |
1947年 | 1篇 |
1935年 | 1篇 |
1934年 | 1篇 |
1933年 | 2篇 |
1932年 | 1篇 |
排序方式: 共有200条查询结果,搜索用时 15 毫秒
21.
The peer relationships of young children with mild developmental (cognitive) delays recruited at 4-6 years of age were examined in a longitudinal study across a 2-year period. Results revealed only modest increases in children's peer interactions, a high degree of intraindividual stability, and the existence of a poorly organized and conflict-prone pattern of peer interactions. Child cognitive and language levels as well as family stress and support were associated with children's peer interactions. A subgroup was identified of initially low interactors who were at especially high risk for future peer interaction problems. These findings further underscore the importance of designing and implementing early intervention programs in the area of peer relationships for children with mild developmental delays. 相似文献
22.
Ruan WJ Lin J Xu EP Xu FY Ma Y Deng H Huang Q Lv BJ Hu H Cui J Di MJ Dong JK Lai MD 《Journal of Zhejiang University. Science. B》2006,7(11):929-932
Insulin-like growth factor binding-protein-7 (IGFBP7) was obtained from our previous colonic adenocarcinoma (CRC) and normal mucosa suppression subtraction hybridization (SSH) cDNA libraries. By RT-PCR and immunohistochemistry, we found that IGFBP7 was overexpressed in CRC tissue compared to normal tissue. However, our in vitro experiments performed in 10 CRC cell lines showed that IGFBP7 expressed only in SW480 and Caco2 cell lines, which implied an underlying reversible regulatory mechanism. Using methylation-specific PCR (MSP) and bisulfite sodium PCR (BSP), we found that its expression was associated with DNA hypomethylation of exonl. This was further supported by the in vitro study which showed restored IGFBP7 expression after demethylation agent 5-aza-2'-deoxycytidine treatment. Correlation analysis between IGFBP7 expression and prognosis indicated that overexpression of IGFBP7 in CRC tissue correlated with favourable survival. Investigation of the functional role of IGFBP7 through transfection studies showed that IGFBP7 protein could inhibit growth rate, decrease colony formation activity, and induce apoptosis in RKO and SW620 cells, suggesting it a potential tumor suppressor protein in colorectal carcinogenesis. In conclusion, our study clearly demonstrated that IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis and its expression is associated with DNA hypomethylation of exon 1. 相似文献
23.
OBJECTIVE: This study's aim was to examine variables associated with different short-term trajectories in multiply disadvantaged adolescent mothers by investigating antecedents and concomitants of parenting stress. METHOD: We followed 49 adolescent mothers (ages 14-18 at study outset) who were wards in Illinois foster care using a longitudinal correlational design. We examined whether parenting variables (childrearing beliefs, quality of parent-child interactions, and child abuse risk) and personal adjustment variables (emotional distress and social support) at initial assessment predicted parenting stress measured at follow-up (a mean of 22.5 months later). We also examined concurrent relationships between parenting stress and mothers' adaptive functioning in educational, social support, and childbirth areas at follow-up. RESULTS: We found that parenting variables, but not personal adjustment variables, predicted later parenting stress. Results also showed that current adaptive functioning was significantly related to parenting stress. Specifically, educational status and social support predicted concurrent parenting stress, whereas number of childbirths did not. CONCLUSIONS: These findings extend the small literature on the link between parenting difficulties and parenting stress to adolescent mothers in foster care. Parenting challenges, particularly as reflected in unrealistic childrearing expectations, appear to be markers for later parenting stress. Considering the longitudinal relationships observed, early and periodic assessment of adolescent mothers' parenting knowledge, skills, and interactions is recommended. Also, given that this study found concurrent social support and educational status to covary with current parental stress, these variables, and others for which they may serve as proxy, are implicated for careful monitoring. 相似文献
24.
25.
National stakeholders are becoming increasingly concerned about the inability of college graduates to think critically. Research shows that, while both faculty and students deem critical thinking essential, only a small fraction of graduates can demonstrate the thinking skills necessary for academic and professional success. Many faculty are considering nontraditional teaching methods that incorporate undergraduate research because they more closely align with the process of doing investigative science. This study compared a research-focused teaching method called community-based inquiry (CBI) with traditional lecture/laboratory in general education biology to discover which method would elicit greater gains in critical thinking. Results showed significant critical-thinking gains in the CBI group but decreases in a traditional group and a mixed CBI/traditional group. Prior critical-thinking skill, instructor, and ethnicity also significantly influenced critical-thinking gains, with nearly all ethnicities in the CBI group outperforming peers in both the mixed and traditional groups. Females, who showed decreased critical thinking in traditional courses relative to males, outperformed their male counterparts in CBI courses. Through the results of this study, it is hoped that faculty who value both research and critical thinking will consider using the CBI method. 相似文献
26.
Nelson ES Coleman PK Swager MJ 《The Journal of humanistic education and development》1997,35(4):217-224
College students completed a questionnaire that assessed their attitudes toward the level of male responsibility in abortion decisions. Overall, both men and women thought that men should have some degree of involvement in the abortion decision. However, as expected by the first hypothesis, men indicated a desire for more responsibility in the abortion decision than women thought the men should have. A second hypothesis predicted women would feel more strongly than men that abortion was strictly a woman's issue. Contrary to the hypothesis, women tended to disagree that abortion was strictly a women's issue. Implications of the findings are discussed. 相似文献
27.
Salivary cortisol as a predictor of socioemotional adjustment during kindergarten: a prospective study 总被引:2,自引:0,他引:2
Smider NA Essex MJ Kalin NH Buss KA Klein MH Davidson RJ Goldsmith HH 《Child development》2002,73(1):75-92
This study, based on a sample of 172 children, examined the relation between average afternoon salivary cortisol levels measured at home at age 4.5 years and socioemotional adjustment a year and a half later, as reported by mothers, fathers, and teachers. Cortisol levels were hypothesized to be positively associated with withdrawal-type behaviors (e.g., internalizing, social wariness) and inversely related to approach-type behaviors, both negative and positive (e.g., externalizing, school engagement). Higher cortisol levels at age 4.5 predicted more internalizing behavior and social wariness as reported by teachers and mothers, although child gender moderated the relation between cortisol and mother report measures. An inverse relation was found between boys' cortisol levels and father report of externalizing behavior. A marginal inverse relation was found between child cortisol levels and teacher report of school engagement. Behavior assessed concurrently with cortisol collection did not account for the prospective relations observed,suggesting that cortisol adds uniquely to an understanding of behavioral development. 相似文献
28.
29.
van Ijzendoorn MH Moran G Belsky J Pederson D Bakermans-Kranenburg MJ Kneppers K 《Child development》2000,71(4):1086-1098
Do siblings develop similar attachment relationships with their mother? Attachment theory suggests that brothers and sisters growing up in the same family are likely to relate in similar ways to their parents, at least when parental attachment representations and interactive styles remain stable across time. In the current study, sibling attachment data from three research groups (from Pennsylvania State University, Leiden University, and the University of Western Ontario) have been pooled to assemble a sufficiently large sample of observations (N = 138 sibling pairs) for a detailed comparison of sibling attachment relationships. Spacing between the births, differences in maternal sensitivity, and gender of siblings were examined as possible sources of concordance of nonconcordance. Attachment security (including disorganized attachment) of each sibling was assessed with the Strange Situation procedure between 12 and 14 months after birth. Maternal sensitivity was observed with the same rating scale in a laboratory play session in one of the studies and in home observations in the others. Sibling relationships were found to be significantly concordant when classified as secure/nonsecure (62% concordance, p < .01, 1-tailed, intraclass correlation = .23) but not when further subcategorized. Maternal insensitivity to both siblings (shared environment) was associated with concordance of sibling nonsecurity. Siblings of the same gender were more likely to form concordant relationships with their mother (68%; p < .01, 1-tailed, intraclass correlation = .37) than those of opposite gender. Same-sex sibling concordance was comparable to the concordance found for monozygotic twins in earlier studies. Genetic factors may, therefore, play a relatively small role in the development of attachment. 相似文献
30.