全文获取类型
收费全文 | 14534篇 |
免费 | 28篇 |
国内免费 | 5篇 |
专业分类
教育 | 11161篇 |
科学研究 | 1455篇 |
各国文化 | 32篇 |
体育 | 567篇 |
综合类 | 13篇 |
文化理论 | 428篇 |
信息传播 | 911篇 |
出版年
2022年 | 35篇 |
2021年 | 49篇 |
2020年 | 60篇 |
2019年 | 109篇 |
2018年 | 2273篇 |
2017年 | 2184篇 |
2016年 | 1658篇 |
2015年 | 179篇 |
2014年 | 201篇 |
2013年 | 657篇 |
2012年 | 307篇 |
2011年 | 768篇 |
2010年 | 909篇 |
2009年 | 488篇 |
2008年 | 708篇 |
2007年 | 1221篇 |
2006年 | 124篇 |
2005年 | 474篇 |
2004年 | 531篇 |
2003年 | 469篇 |
2002年 | 222篇 |
2001年 | 92篇 |
2000年 | 74篇 |
1999年 | 36篇 |
1998年 | 23篇 |
1997年 | 36篇 |
1996年 | 31篇 |
1995年 | 31篇 |
1994年 | 29篇 |
1993年 | 33篇 |
1992年 | 24篇 |
1991年 | 39篇 |
1990年 | 19篇 |
1989年 | 35篇 |
1987年 | 18篇 |
1986年 | 14篇 |
1985年 | 19篇 |
1984年 | 18篇 |
1983年 | 21篇 |
1982年 | 27篇 |
1981年 | 16篇 |
1980年 | 20篇 |
1979年 | 18篇 |
1978年 | 19篇 |
1977年 | 20篇 |
1976年 | 14篇 |
1974年 | 21篇 |
1973年 | 21篇 |
1968年 | 14篇 |
1967年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
Peter Wood 《Academic Questions》2017,30(2):245-252
103.
104.
105.
106.
107.
Shoudong Wang Shulin Liu Jie Wang Kengo Yokosho Bin Zhou Ya-Chi Yu Zhi Liu Wolf B Frommer Jian Feng Ma Li-Qing Chen Yuefeng Guan Huixia Shou Zhixi Tian 《国家科学评论(英文版)》2020,7(11):1776
Soybean accounts for more than half of the global production of oilseed and more than a quarter of the protein used globally for human food and animal feed. Soybean domestication involved parallel increases in seed size and oil content, and a concomitant decrease in protein content. However, science has not yet discovered whether these effects were due to selective pressure on a single gene or multiple genes. Here, re-sequencing data from >800 genotypes revealed a strong selection during soybean domestication on GmSWEET10a. The selection of GmSWEET10a conferred simultaneous increases in soybean-seed size and oil content as well as a reduction in the protein content. The result was validated using both near-isogenic lines carrying substitution of haplotype chromosomal segments and transgenic soybeans. Moreover, GmSWEET10b was found to be functionally redundant with its homologue GmSWEET10a and to be undergoing selection in current breeding, leading the the elite allele GmSWEET10b, a potential target for present-day soybean breeding. Both GmSWEET10a and GmSWEET10b were shown to transport sucrose and hexose, contributing to sugar allocation from seed coat to embryo, which consequently determines oil and protein contents and seed size in soybean. We conclude that past selection of optimal GmSWEET10a alleles drove the initial domestication of multiple soybean-seed traits and that targeted selection of the elite allele GmSWEET10b may further improve the yield and seed quality of modern soybean cultivars. 相似文献
108.
109.
Jin Woo Lee Anastasia Ostrowski Aileen Huang-Saad Colleen M. Seifert 《European Journal of Engineering Education》2019,44(3):360-378
ABSTRACTWith increasing demand for improved medical equipment and healthcare, next-generation biomedical engineers need strong design skills. Equipping biomedical engineering students with tools for idea generation and development can increase student design success. Design Heuristics are an ideation tool developed through empirical studies of product designs. While identified in the mechanical engineering space, Design Heuristics may be applicable in biomedical engineering design. In our study, we implemented a Design Heuristics session during upper-level undergraduate and first-year graduate biomedical engineering design courses. We examined the applicability of Design Heuristics within individual and team concept generation contexts. The findings demonstrated that biomedical engineering students were able to use Design Heuristics to generate multiple concepts, and that initial concepts produced using Design Heuristics were carried over into final team design. The results support the applicability of Design Heuristics to student idea generation in biomedical engineering design. 相似文献
110.
José Roberto Andrade do Nascimento-Junior Leonardo de Sousa Fortes Gabriel Lucas Morais Freire Daniel Vicentini de Oliveira Lenamar Fiorese Lorcan Donal Cronin 《Measurement in physical education and exercise science》2020,24(1):11-24
ABSTRACTThis research adapted the Life Skills Scale for Sport (LSSS) into Portuguese and provided evidence for its construct validity. Study 1 included four translators and five academics who developed a Portuguese version of the LSSS (P-LSSS). During this study, evidence for the content and substantive aspects of construct validity was provided using an expert panel and 25 sports participants. Study 2 included 413 participants that completed the P-LSSS. Within this study, evidence for the structural aspect of construct validity was provided via factor analyses. Study 3 included 134 participants who completed the P-LSSS and a measure of motivation. This study provided evidence for the external aspect of construct validity, with results showing more self-determined motivation had positive relationships with participant’s life skills development. Overall, our findings provided evidence for the construct validity of P-LSSS scores. Researchers and practitioners can use the P-LSSS to assess life skills development within sports participants. 相似文献