首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   232篇
  免费   5篇
教育   159篇
科学研究   37篇
各国文化   3篇
体育   7篇
文化理论   1篇
信息传播   30篇
  2023年   2篇
  2022年   7篇
  2021年   6篇
  2020年   3篇
  2019年   12篇
  2018年   16篇
  2017年   12篇
  2016年   8篇
  2015年   3篇
  2014年   12篇
  2013年   42篇
  2012年   15篇
  2011年   12篇
  2010年   7篇
  2009年   10篇
  2008年   7篇
  2007年   11篇
  2006年   10篇
  2005年   4篇
  2004年   1篇
  2003年   5篇
  2002年   6篇
  2001年   2篇
  2000年   4篇
  1999年   3篇
  1997年   3篇
  1996年   2篇
  1994年   1篇
  1993年   1篇
  1991年   2篇
  1990年   1篇
  1989年   1篇
  1980年   3篇
  1979年   1篇
  1975年   1篇
  1968年   1篇
排序方式: 共有237条查询结果,搜索用时 31 毫秒
31.
32.
The researchers conducted a grounded theory study to explore the experiences of Muslim American adolescents in high school. Findings indicate that students had to navigate unique challenges because of their religious faith, but those obstacles presented opportunities to confront bias and discrimination. Recommendations for how school counselors can support the development of Muslim American adolescents are presented.  相似文献   
33.
ABSTRACT

Although research on private tutoring has gained visibility in recent years, private tutoring in English (PT-E) has not received notable attention. This paper examines students’ perceptions of PT-E in Bangladesh in terms of its necessity and helpfulness, peer pressure in PT-E participation and ethicality of PT-E practice and government intervention. Our analysis of survey data (N?=?572) leads to characterising PT-E and explaining the reasons for its popularity. As a popular learning space beyond formal schooling, PT-E is available in various forms and quality catering to the purchasing power of different social groups. We argue that students may resort to PT-E not because of its proven effectiveness but because of their declining faith in school English teaching. The paper contributes to our understanding of the complex interactions between the curricular (school) and non-curricular (PT-E) settings and family socioeconomic resources in the teaching of English as a globally desired language.  相似文献   
34.
35.
In this paper, the issue of output voltage regulation in buck type dc-dc converters is addressed using a current sensorless control technique. The proposed strategy integrates a finite time current observer with an adaptive backstepping control scheme to yield a cost-effective and robust control mechanism. The overall controller stability in the sense of Lyapunov is proved. Applicability of the proposed control is verified experimentally on a buck converter in the laboratory. The control scheme is implemented on dSPACE DS1103 platform based on DSP TM320F240 processor. To examine the efficacy of the proposed method, the buck converter is subjected to a wide change in input voltage, load resistance and reference voltage. For comparison purpose, a conventional adaptive backstepping control scheme is evaluated under identical conditions of experimental study to examine the merit of the proposed control. The results obtained reveal that the proposed control is prompt in rejecting perturbations and achieves a smooth, reliable and satisfactory output voltage regulation with faithful and time bound estimation of inductor current. Thereby, this investigation demonstrates the validity of the proposed control in maintaining a stringent output voltage regulation in buck converters.  相似文献   
36.
Despite being invasive within surrounding brain tissues and the central nervous system, little is known about the mechanical properties of brain tumor cells in comparison with benign cells. Here, we present the first measurements of the peak pressure drop due to the passage of benign and cancerous brain cells through confined microchannels in a “microfluidic cell squeezer” device, as well as the elongation, speed, and entry time of the cells in confined channels. We find that cancerous and benign brain cells cannot be differentiated based on speeds or elongation. We have found that the entry time into a narrow constriction is a more sensitive indicator of the differences between malignant and healthy glial cells than pressure drops. Importantly, we also find that brain tumor cells take a longer time to squeeze through a constriction and migrate more slowly than benign cells in two dimensional wound healing assays. Based on these observations, we arrive at the surprising conclusion that the prevailing notion of extraneural cancer cells being more mechanically compliant than benign cells may not apply to brain cancer cells.  相似文献   
37.
The study has been undertaken as number of sickle cell patients in Chhattisgarh tribal population is 23.7 %. The Co enzyme Q10 is a strong antioxidant and energy producing compound. The patients were divided into three groups group A homozygous (SS), group B heterozygous (AS) and group C controls for TBARS study. The age group is 10–55 years and 200 mg of CoQ10 was given to A and B groups. The hematological parameters, C reactive protein as well as RBC TBARS level were performed by usual and standard techniques. The results were obtained as 25.37 % increased RBC level in group A and 23.24 % in group B. The increased hemoglobin level was observed as 16.73 % in group A and 10.7 % in group B. In case of WBC it was observed increased 24.38 % in group A and 12.0 % in group B. C-reactive protein was observed 7.8 times decreased in group A and 1.54 times in group B. The RBC TBARS level was also found decreased 48 % in group A and 51 % in group B as compared to group C. During the supplementation of coenzyme Q10 the pain caused by vaso-occlusive events has reduced. This significant increase in hematological parameters as well as decreased C-reactive protein and TBARS level suggest that the Q10 should be included in the diet of sickle cell patients.  相似文献   
38.
Numerous events have provided evidence that the cultural values and assumptions of intercollegiate athletic departments are often incongruent with those of their host institutions. This discrepancy has even been evident in Christian institutions which seek to integrate faith into the learning experience. Using the organizational culture perspective, this study sought to determine how religion influenced the culture of one intercollegiate athletics department. The study took place at a highly selective evangelical Christian college with a nationally competitive athletic department. Data were collected through interviews with 19 campus leaders, observation of cultural events and document analysis. Analysis occurred qualitatively through a process of theorizing. The results indicate that evangelical Christianity played a significant role in the athletic department's culture by constraining its membership, influencing its pedagogy and guiding department decisions. As a result, its values and assumptions were consistent with those of the overall campus culture. The reasons underlying this cultural integration offer coaches and administrators of all institutional affiliations the possibility that the organizational culture perspective can be used to create athletic programs that are more consistent with institutional values.  相似文献   
39.
40.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号