全文获取类型
收费全文 | 396篇 |
免费 | 6篇 |
专业分类
教育 | 315篇 |
科学研究 | 12篇 |
各国文化 | 2篇 |
体育 | 40篇 |
文化理论 | 6篇 |
信息传播 | 27篇 |
出版年
2023年 | 2篇 |
2022年 | 9篇 |
2021年 | 7篇 |
2020年 | 14篇 |
2019年 | 18篇 |
2018年 | 23篇 |
2017年 | 25篇 |
2016年 | 16篇 |
2015年 | 9篇 |
2014年 | 21篇 |
2013年 | 68篇 |
2012年 | 23篇 |
2011年 | 20篇 |
2010年 | 21篇 |
2009年 | 13篇 |
2008年 | 12篇 |
2007年 | 14篇 |
2006年 | 9篇 |
2005年 | 8篇 |
2004年 | 10篇 |
2003年 | 8篇 |
2002年 | 8篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1991年 | 1篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1981年 | 1篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
排序方式: 共有402条查询结果,搜索用时 15 毫秒
101.
Paul R. Salomone is a professor of Counselor Education and of Rehabilitation Counseling at Syracuse University. Claudia Pask-McCartney is a doctoral candidate in the area of Instructional Design, Development, and Evaluation at Syracuse University. 相似文献
102.
103.
104.
Over the past decade, curricular reform in mathematics education has emphasized the use of problem solving at all levels of instruction for all students, but adaptations for students with unique needs have not been specified. This study investigated the nature of problem solving in deaf education, focusing in particular on the use of story problems in the primary-level curriculum. Approximately 90% of the K-3 teachers from five schools for the deaf were asked with what frequency and in which communication mode they presented story problems to their students. Most teachers reported presenting story problems 1-3 times per week, and presentation method tended to reflect school communication philosophy. We found trends in story problem presentation in accordance with the mathematics grade level taught. We discuss implications for curricular reform and teacher education. 相似文献
105.
The purpose of this paper is to review ten actions that can be taken by multi- disciplinary child protection teams or individuals in this field to assure that the interests of the abused child are consistently addressed. 相似文献
106.
The results of previous cross-section studies suggest that childhood hearing impairment may lead to parental psychosocial stress. The present study investigated whether modifications in parental psychic state can be ascertained in connection with the child's treatment events and the child's hearing and speech status, in a prospective study design. Data were available on 116 fathers and mothers regarding the pre-cochlear implant examination or hearing aid fitting of their child. In the course of the child's treatment, parental quality of life improved from a low to a normal level. Among children who were at the stage of pre-examination for a cochlear implant, better hearing and speech capacity was linked to more severe impairment of the parental state. It is emphasized that the parents whose children showed comparatively good language development at the time of pre-examination for a cochlear implant were especially subjected to stress. 相似文献
107.
108.
This paper uses a unique data set of Mexican researchers to explore the determinants of research output and impact. Our findings confirm a quadratic relationship between age and the number of published papers. However, publishing peaks when researchers are approximately 53 years old, 5 or 10 years later than what prior studies have shown. Overall, the results suggest that age does not have a substantial influence on research output and impact. We also find that reputation matters for the number of citations but not publications. Results also show important heterogeneity across areas of knowledge. Interpretations of other aspects, such as gender, country of PhD, and cohort effect, among others, are also discussed. 相似文献
109.
Graziella Bonetti Mariarosa Carta Martina Montagnana Claudia Lo Cascio Anna Rita Bonfigli Andrea Mosca Roberto Testa 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2016,26(1):68-76
Introduction
Glycolysis affects glucose determination in vitro. The placement of sample tubes in ice-water slurry with plasma separation within 30 minutes is recommended, or alternatively the use of a glycolysis inhibitor. The aim of our two-steps study was to evaluate which Terumo tube is best for glucose determination in routine clinical setting.Materials and methods
In the first study, blood from 100 volunteers was collected into lithium heparin (LH), NaF/Na heparin (FH) and NaF/citrate buffer/Na2EDTA (FC-Mixture) tubes. LH sample was treated as recommended and considered as reference, while FH and FC-Mixture samples were aliquoted, maintained at room temperature (RT) for 1, 2 and 4 hours; centrifuged and plasma analysed in triplicate. In the second study, samples from 375 volunteers were collected in LH, FH and FC-Mixture tubes and held at RT before centrifugation from 10 to 340 minutes, depending on each laboratory practice. Samples were analysed in one analytical run.Results
In the first study, FH glucose concentrations were 5.15 ± 0.66 mmol/L, 5.05 ± 0.65 mmol/L and 5.00 ± 0.65 mmol/L (P < 0.001) in tubes stored at RT for 1, 2 and 4 hours, respectively. Mean biases in all time points exceeded the analytical goal for desirable bias based on biological variation criteria. FC-Mixture glucose concentrations were 5.48 ± 0.65 mmol/L, 5.46 ± 0.6 mmol/L and 5.46 ± 0.64 mmol/L in tubes stored at RT for 1, 2 and 4 hours, respectively. Mean biases for FC-Mixture glucose in all time points reached optimal analytical goals. In the second study, the biases for LH and FH glucose compared to reference FC-Mixture glucose exceeded the preset analytical goals, regardless of the blood collection to centrifugation time interval.Conclusions
FC-mixture tubes glucose concentrations were preserved up to 4h storage at RT. We confirmed that NaF alone does not allow immediate glycolysis inhibition in real life pre-centrifugation storage conditions (up to 340 minutes). FC-Mixture should be used exclusively for glucose determination in laboratories unable to implement the recommended blood samples’ treatment.Key words: glucose, pre-analytical phase, sodium fluoride, citrate acidification, stability 相似文献110.
Paul Kim Claudia Olaciregui 《British journal of educational technology : journal of the Council for Educational Technology》2008,39(4):700-714
An electronic portfolio system, designed to serve as a resource-based learning space, was tested in a fifth-grade science class. The control-group students accessed a traditional folder-based information display in the system and the experimental-group students accessed a concept map-based information display to review a science portfolio. The student-constructed science portfolio was a result of a collection of digital artefacts such as graphic images, instructional videos and textual files on terms and definitions relevant to the Earth's atmosphere. In the information-processing performance test, the experimental-group students scored significantly higher and spent much less time in finding answers to the questions presented. Also, in the 3-day delayed memory retention tests, the experimental-group students achieved significantly higher scores. The multiple regression models confirm that the visualisation variation is the most significant predictor for student performance (ie, comprehension and access time). Also, the regression models suggest that language-arts proficiency may reduce overall system access time; while higher math proficiency may predict retention scores. 相似文献