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991.
Background: Systematic review articles support the advance of science and translation of research evidence into healthcare practice. Inaccurate retrieval from medline could limit access to reviews. Objective: To determine the quality of indexing systematic reviews and meta‐analyses in medline . Methods: The Clinical Hedges Database, containing the results of a hand search of 161 journals, was used to test medline indexing terms for their ability to retrieve systematic reviews that met predefined methodologic criteria (labelled as ‘pass’ review articles) and reviews that reported a meta‐analysis. Results: The Clinical Hedges Database contained 49 028 articles; 753 were ‘pass’ review articles (552 with a meta‐analysis). In total 758 review articles (independent of whether they passed) reported a meta‐analysis. The search strategy that retrieved the highest number of ‘pass’ systematic reviews achieved a sensitivity of 97.1%. The publication type ‘meta analysis’ had a false positive rate of 5.6% (95% CI 3.9 to 7.6), and false negative rate of 0.31% (95% CI 0.26 to 0.36) for retrieving systematic reviews that reported a meta‐analysis. Conclusions: Inaccuracies in indexing systematic reviews and meta‐analyses in medline can be partly overcome by a 5‐term search strategy. Introducing a publication type for systematic reviews of the literature could improve retrieval performance. 相似文献
992.
Francesca R. Dillman Carpentier Elise M. Stevens Lu Wu Natalee Seely 《Mass Communication and Society》2017,20(5):686-709
This study documents the extent of sexual content, including sexual health content, in scenes with and without expressions of love on network and cable television popular with emerging adults. Sexual talk and/or behavior was found in 20% of all television scenes coded across 53.5 hours of programming. One third of these scenes featured sex alongside expressions of love. An additional 10% of scenes suggested love but not sex. Coded as a separate category, 25% of analyzed scenes contained a passing joke or pun referencing sexual organs, making these nonspecific, comedic one-liners the predominant reference to sex in this sample. Beyond jokes, most of the sexual or loving talk in this sample consisted of expressing a romantic interest in someone; sex- and love-related behaviors largely consisted of kissing or flirting. Very few scenes specifically referenced sexual intercourse. Sexual health messages were also rare. The majority of scenes mentioning any health consequence (7% of analyzed scenes) concerned emotional heartache. One scene mentioned sexually transmitted infections; 12 of the nearly 2,600 scenes coded mentioned condoms or contraceptives. It is thus a challenging proposition to build upon existing sexual depictions on television to promote safe sex practices within sexual and loving contexts. 相似文献
993.
994.
Women in American science 总被引:3,自引:0,他引:3
995.
The study examined the extent to which a highly qualified interpreter remained parallel with or diverged from the original classroom discourse in her interpreting for a 3rd-grade deaf student in science, social studies, and resource room. The interpreter's signed and verbalized expressions were compared to the class participants' expressions for meaning equivalence. Parallel interpreting, occurring 33.2% of the time, closely matched the content of the speaker's message. Divergent interpreting, whereby the interpreter added or dropped elements of meaning, occurred 66.8% of the time. Qualitative analyses of classroom footage as well as interviews with the interpreter and the teachers revealed how, when, and why the interpreter diverged from the message. While the interpreter often made intentional reductions and additions to the discourse to achieve greater student understanding of language and course content, there was little awareness of these changes among individualized educational program team members. 相似文献
996.
Individual Differences in Childhood Behavior Disorders Associated With Epigenetic Modulation of the Cortisol Receptor Gene 下载免费PDF全文
Mark R. Dadds Caroline Moul David J. Hawes Antonio Mendoza Diaz John Brennan 《Child development》2015,86(5):1311-1320
Behavioral/emotional difficulties in children are the first sign of mental health problems. These problems are however, heterogeneous. A domain that may identify homogenous subgroups is hypothalamic–pituitary–adrenal function. This study tested whether epigenetic regulation of glucocorticoid receptor gene could explain the co‐occurrence of anxiety problems in children with behavior problems. Four‐ to 16‐year‐old clinically referred children (N = 241) were measured for psychiatric symptoms, methylation of target CpG sites in blood or saliva, and morning cortisol levels in those who gave blood. Increased methylation of promoter 1F CpG sites was associated with higher vulnerability to co‐occurring internalizing symptoms and morning cortisol. The results support increasing optimism that epigenetic regulation of key neuroendocrine systems might help explain hitherto unfathomable individual differences in susceptibility to psychiatric symptom profiles. 相似文献
997.
998.
Necessary and sufficient conditions for the realization of lossless, lowpass, ladder networks terminated by a resistance are presented, in terms of the poles and zeros of the reflection coefficient. These conditions yield explicit expressions for the element values. They are then extended to highpass networks. These results are next used in solving a bandpass matching problem and the limitations on the performance of matching networks due to constraints imposed by the load are discussed. A suitable example is worked out to illustrate the problem. 相似文献
999.
The relationship between students and their academic institution is based on exchange. However, we have limited knowledge regarding how many exchanges students perceive, who (or what) the perceived exchange partners are, and what the perceived terms of those exchanges contain. To address this gap, we utilized a mixed-method approach to explore and describe the psychological contracts of two sets of undergraduate university students: newly entering freshman, and experienced university students. Results clearly demonstrated that students perceive numerous psychological contracts relevant to their education with a variety of partners both inside and at the boundaries of the institution. Results also demonstrated that these contracts are qualitatively and quantitatively distinct. The overarching implication of these findings is that students navigate a web of diverse exchange partners, and it would be a mistake for educators and researchers to focus exclusively on one or few relationships presupposed to be most important. 相似文献
1000.
Examining preservice teacher content and pedagogical content knowledge needed to teach reading in elementary school 下载免费PDF全文
Recently, increased attention has been placed on the importance of having knowledgeable and skilled teachers in order to influence reading achievement. Yet many international reports suggest that large numbers of children are not learning to read. How can we better prepare teachers with the necessary knowledge to teach reading? The current study examined the reading instructional knowledge of elementary education preservice teachers (N = 87) from two teacher education programmes. Programme A required five reading methods courses and Programme B required two methods courses. Findings indicate that the preservice teachers presented fairly robust levels of knowledge in the areas of phonological awareness, phonics, comprehension and vocabulary. However, we found statistically significant differences in knowledge based on the programme attended and the number of courses completed. Suggestions for improving reading teacher education are provided. 相似文献