全文获取类型
收费全文 | 5103篇 |
免费 | 397篇 |
国内免费 | 479篇 |
专业分类
5979篇 |
出版年
2024年 | 18篇 |
2023年 | 75篇 |
2022年 | 165篇 |
2021年 | 237篇 |
2020年 | 168篇 |
2019年 | 199篇 |
2018年 | 183篇 |
2017年 | 150篇 |
2016年 | 187篇 |
2015年 | 299篇 |
2014年 | 376篇 |
2013年 | 378篇 |
2012年 | 478篇 |
2011年 | 444篇 |
2010年 | 283篇 |
2009年 | 241篇 |
2008年 | 299篇 |
2007年 | 255篇 |
2006年 | 224篇 |
2005年 | 195篇 |
2004年 | 157篇 |
2003年 | 161篇 |
2002年 | 149篇 |
2001年 | 60篇 |
2000年 | 73篇 |
1999年 | 65篇 |
1998年 | 61篇 |
1997年 | 50篇 |
1996年 | 40篇 |
1995年 | 46篇 |
1994年 | 45篇 |
1993年 | 25篇 |
1992年 | 29篇 |
1991年 | 19篇 |
1990年 | 25篇 |
1989年 | 25篇 |
1988年 | 12篇 |
1987年 | 5篇 |
1986年 | 10篇 |
1985年 | 12篇 |
1984年 | 9篇 |
1983年 | 8篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1976年 | 3篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1968年 | 3篇 |
排序方式: 共有5979条查询结果,搜索用时 10 毫秒
991.
Lan Yu Rongkai Guo Yeqin Jiang Xinghuo Ye Zhihong Yang 《Bioscience, biotechnology, and biochemistry》2019,83(2):233-242
MicroRNAs (miRNAs) are important and ubiquitous regulators of gene expression in eukaryotes. However, the information about miRNAs population and their regulatory functions involving in soybean seed development remains incomplete. Base on the Dicer-like1-mediated cleavage signals during miRNA processing could be employed for novel miRNA discovery, a genome-wide search for miRNA candidates involved in seed development was carried out. As a result, 17 novel miRNAs, 14 isoforms of miRNA (isomiRs) and 31 previously validated miRNAs were discovered. These novel miRNAs and isomiRs represented tissue-specific expression and the isomiRs showed significantly higher abundance than that of their miRNA counterparts in different tissues. After target prediction and degradome sequencing data-based validation, 13 novel miRNA–target pairs were further identified. Besides, five targets of 22-nt iso-gma-miR393h were found to be triggered to produce secondary trans-acting siRNA (ta-siRNAs). Summarily, our results could expand the repertoire of miRNAs with potentially important functions in soybean. 相似文献
992.
993.
994.
995.
996.
997.
Sustained molecular oscillations are ubiquitous in biology. The obtained oscillatory patterns provide vital functions as timekeepers, pacemakers and spacemarkers. Models based on control theory have been introduced to explain how specific oscillatory behaviors stem from protein interaction feedbacks, whereas the energy dissipation through the oscillating processes and its role in the regulatory function remain unexplored. Here we developed a general framework to assess an oscillator’s regulation performance at different dissipation levels. Using the Escherichia coli MinCDE oscillator as a model system, we showed that a sufficient amount of energy dissipation is needed to switch on the oscillation, which is tightly coupled to the system’s regulatory performance. Once the dissipation level is beyond this threshold, unlike stationary regulators’ monotonic performance-to-cost relation, excess dissipation at certain steps in the oscillating process damages the oscillator’s regulatory performance. We further discovered that the chemical free energy from ATP hydrolysis has to be strategically assigned to the MinE-aided MinD release and the MinD immobilization steps for optimal performance, and a higher energy budget improves the robustness of the oscillator. These results unfold a novel mode by which living systems trade energy for regulatory function. 相似文献
998.
999.
1000.