全文获取类型
收费全文 | 5712篇 |
免费 | 697篇 |
国内免费 | 5篇 |
专业分类
电工技术 | 42篇 |
综合类 | 3篇 |
化学工业 | 1827篇 |
金属工艺 | 171篇 |
机械仪表 | 348篇 |
建筑科学 | 75篇 |
矿业工程 | 3篇 |
能源动力 | 232篇 |
轻工业 | 710篇 |
水利工程 | 10篇 |
石油天然气 | 3篇 |
无线电 | 930篇 |
一般工业技术 | 1349篇 |
冶金工业 | 132篇 |
原子能技术 | 59篇 |
自动化技术 | 520篇 |
出版年
2024年 | 6篇 |
2023年 | 76篇 |
2022年 | 134篇 |
2021年 | 241篇 |
2020年 | 184篇 |
2019年 | 218篇 |
2018年 | 224篇 |
2017年 | 256篇 |
2016年 | 287篇 |
2015年 | 271篇 |
2014年 | 350篇 |
2013年 | 393篇 |
2012年 | 492篇 |
2011年 | 547篇 |
2010年 | 392篇 |
2009年 | 336篇 |
2008年 | 327篇 |
2007年 | 226篇 |
2006年 | 211篇 |
2005年 | 196篇 |
2004年 | 165篇 |
2003年 | 167篇 |
2002年 | 124篇 |
2001年 | 91篇 |
2000年 | 66篇 |
1999年 | 78篇 |
1998年 | 58篇 |
1997年 | 57篇 |
1996年 | 47篇 |
1995年 | 36篇 |
1994年 | 26篇 |
1993年 | 20篇 |
1992年 | 19篇 |
1991年 | 14篇 |
1990年 | 17篇 |
1989年 | 14篇 |
1988年 | 13篇 |
1987年 | 9篇 |
1986年 | 6篇 |
1985年 | 9篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1976年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有6414条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
In vivo Kinetic Biodistribution of Nano‐Sized Outer Membrane Vesicles Derived from Bacteria
下载免费PDF全文
![点击此处可从《Small (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Su Chul Jang Sae Rom Kim Yae Jin Yoon Kyong‐Su Park Ji Hyun Kim Jaewook Lee Oh Youn Kim Eun‐Jeong Choi Dae‐Kyum Kim Dong‐Sic Choi Yoon‐Keun Kim Jaesung Park Dolores Di Vizio Yong Song Gho 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(4):456-461
Evaluation of kinetic distribution and behaviors of nanoparticles in vivo provides crucial clues into their roles in living organisms. Extracellular vesicles are evolutionary conserved nanoparticles, known to play important biological functions in intercellular, inter‐species, and inter‐kingdom communication. In this study, the first kinetic analysis of the biodistribution of outer membrane vesicles (OMVs)—bacterial extracellular vesicles—with immune‐modulatory functions is performed. OMVs, injected intraperitoneally, spread to the whole mouse body and accumulate in the liver, lung, spleen, and kidney within 3 h of administration. As an early systemic inflammation response, increased levels of TNF‐α and IL‐6 are observed in serum and bronchoalveolar lavage fluid. In addition, the number of leukocytes and platelets in the blood is decreased. OMVs and cytokine concentrations, as well as body temperature are gradually decreased 6 h after OMV injection, in concomitance with the formation of eye exudates, and of an increase in ICAM‐1 levels in the lung. Following OMV elimination, most of the inflammatory signs are reverted, 12 h post‐injection. However, leukocytes in bronchoalveolar lavage fluid are increased as a late reaction. Taken together, these results suggest that OMVs are effective mediators of long distance communication in vivo. 相似文献
7.
8.
9.
Properties and applications of β‐glycosidase from Bacteroides thetaiotaomicron that specifically hydrolyses isoflavone glycosides
下载免费PDF全文
![点击此处可从《International Journal of Food Science & Technology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Da‐Hye Byun Hye‐Jeong Choi Hye‐Won Lee Hye‐Yeon Jeon Woo‐Jae Choung Jae‐Hoon Shim 《International Journal of Food Science & Technology》2015,50(6):1405-1412
To modify the glycan part of glycosides, the gene encoding β‐glycosidase was cloned from Bacteroides thetaiotaomicron VPI‐5482. The cloned gene, bt_1780, was expressed in Escherichia coli MC1061 and the expressed enzyme was purified using Ni‐NTA affinity chromatography. The purified enzyme, BTBG, showed optimal activity at 50 °C and pH 5.5. Interestingly, this enzyme did not have any hydrolysing activity on ordinary β‐linkage–containing substrates such as xylobiose, lactose and cello‐oligosaccharide, but specifically hydrolysed isoflavone glycosides such as daidzin, genistin and glycitin. Compared to a commercial beta glucosidase, BTBG selectively hydrolysed isoflavone glycosides in soybean extract mixture solution. These results suggest that BTBG may be a specialized enzyme for the hydrolysis of glycosides and that the substrate specificity of BTBG is applicable for the bioconversion of isoflavone glycosides in the food industry. 相似文献
10.