全文获取类型
收费全文 | 607篇 |
免费 | 4篇 |
国内免费 | 3篇 |
专业分类
教育 | 319篇 |
科学研究 | 82篇 |
各国文化 | 6篇 |
体育 | 129篇 |
综合类 | 6篇 |
文化理论 | 1篇 |
信息传播 | 71篇 |
出版年
2023年 | 3篇 |
2022年 | 7篇 |
2016年 | 2篇 |
2015年 | 3篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 47篇 |
2011年 | 65篇 |
2010年 | 23篇 |
2009年 | 8篇 |
2008年 | 34篇 |
2007年 | 43篇 |
2006年 | 47篇 |
2005年 | 40篇 |
2004年 | 22篇 |
2003年 | 26篇 |
2002年 | 22篇 |
2001年 | 15篇 |
2000年 | 20篇 |
1999年 | 14篇 |
1998年 | 5篇 |
1997年 | 12篇 |
1996年 | 5篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 6篇 |
1992年 | 8篇 |
1991年 | 10篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 6篇 |
1987年 | 4篇 |
1986年 | 10篇 |
1985年 | 12篇 |
1984年 | 7篇 |
1983年 | 8篇 |
1982年 | 3篇 |
1981年 | 5篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1958年 | 4篇 |
1944年 | 4篇 |
1937年 | 2篇 |
1934年 | 2篇 |
1933年 | 2篇 |
1929年 | 2篇 |
1928年 | 2篇 |
1917年 | 1篇 |
1911年 | 1篇 |
1905年 | 1篇 |
排序方式: 共有614条查询结果,搜索用时 15 毫秒
1.
在体育运动领域里是没有通往金牌的捷径的。献身精神、刻苦训练,良好的基因和有益于中康的饮食就是通往金牌的一切道路。 运动员所使用和误用的所有比赛辅助物中,蛋白质居于大多数误用物质的前列。迎合运动员及 相似文献
3.
4.
INTRODUCTION Carotenoids are a class of natural fat-solublepigments generally found in plants, algae, and pho-tosynthetic bacteria, where they play a critical role inthe photosynthetic process. Carotenoids also exist insome non-photo-synthetic bacteria, yeasts, and moldswhere they may carry out a protective functionagainst damages by light and oxygen. Although ani-mals can not synthesize carotenoids within theirbodies, they can intake carotenoids from their dietsleading to bright meat col… 相似文献
5.
6.
学习领域和教学组织与安排 总被引:1,自引:0,他引:1
彼德F.E.斯鲁阿纳 《中国职业技术教育》2002,(11):12-14
目前,教育界人士对职业学校的专业课程各持己见。有人认为职业技术培训过于理论化岸生无法在课堂上学到足够的应用性知识。所以,提出一个以 相似文献
7.
Peer relations across 2 contexts (in school and after school) were examined for 577 participants, approximately 12 years old, from 3 middle schools in Milan, Italy. The primary research questions were: Do peer networks from different contexts uniquely contribute to explaining variance in individual behavior? Do measures of peer preference and peer network inclusion across contexts uniquely contribute to explaining individual depressive symptoms? Structural equation models showed that both the in-school and the after-school peer networks uniquely contributed to explaining variance in 2 types of individual problem behavior (in-school problem behavior, after-school delinquency), and that similarity with the 2 peer networks varied according to behaviors specific to each context and across gender. Finally, both in-school and after-school peer network inclusion contributed to explaining variance in depressive symptoms, after controlling for classroom peer preference. 相似文献
8.
Who borrows laptop computers in an academic health sciences library? Why do they choose to check out laptops? In a survey, laptop computer users responded that the laptops were used most frequently to do class-related work. Laptops were most often checked out because they could be taken to a quiet area of the library or to where the user had more room to work. The majority of such borrowers were satisfied or very satisfied with the laptops and the service from the library. The majority of those completing the survey were medical school students and graduate students. The circulation of laptop computers at this academic health sciences library is a very successful and popular program. 相似文献
9.
The objective of this study is to propose a more accurate and faster MTT 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assay (MCA) for quantitative measurement of polypeptide bacteriocins in solutions with nisin as an example. After an initial incubation of nisin and indicator bacterium Micrococcus luteus NCIB 8166 in tubes, MTT was added for another incubation period. After that, nisin was quantified by estimating the number of viable bacteria based on measuring the amount of purple formazan produced by cleavage of yellow tetrazolium salt MTT. Then MCA was compared to a standard agar diffusion assay (ADA). The results suggested a high correlation coefficient (r2=0.975±0.004) between optical density (OD) and the inhibitory effect of nisin on a bacterial strain Micrococcus luteus NCIB 8166 at a range of 0.125~32 IU/ml. The MCA described in this study was very quick. Quantification of nisin took only 7~8 h and the detection limit was at the level of 0.125 IU/ml when compared to 12 IU/ml and 24~28 h for ADA. The MCA provides an accurate and rapid method for quantifi-cation of nisin in solutions and is expected to be used for quantification of other antimicrobial substances. 相似文献
10.
Supplemental instruction classes have been shown in many studies to enhance performance in the supported courses and even to improve graduation rates. Generally, there has been little evidence of a differential impact on students from different ethnic/racial backgrounds. At San Francisco State University, however, supplemental instruction in the Introductory Biology I class is associated with even more dramatic gains among students from underrepresented minority populations than the gains found among their peers. These gains do not seem to be the product of better students availing themselves of supplemental instruction or other outside factors. The Introductory Biology I class consists of a team-taught lecture component, taught in a large lecture classroom, and a laboratory component where students participate in smaller lab sections. Students are expected to master an understanding of basic concepts, content, and vocabulary in biology as well as gain laboratory investigation skills and experience applying scientific methodology. In this context, supplemental instruction classes are cooperative learning environments where students participate in learning activities that complement the course material, focusing on student misconceptions and difficulties, construction of a scaffolded knowledge base, applications involving problem solving, and articulation of constructs with peers. 相似文献