全文获取类型
收费全文 | 230篇 |
免费 | 12篇 |
专业分类
林业 | 35篇 |
农学 | 2篇 |
30篇 | |
综合类 | 33篇 |
农作物 | 5篇 |
水产渔业 | 21篇 |
畜牧兽医 | 98篇 |
园艺 | 5篇 |
植物保护 | 13篇 |
出版年
2022年 | 3篇 |
2021年 | 5篇 |
2020年 | 6篇 |
2019年 | 11篇 |
2018年 | 15篇 |
2017年 | 3篇 |
2016年 | 15篇 |
2015年 | 8篇 |
2014年 | 11篇 |
2013年 | 16篇 |
2012年 | 7篇 |
2011年 | 17篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 14篇 |
2007年 | 11篇 |
2006年 | 7篇 |
2005年 | 7篇 |
2004年 | 6篇 |
2003年 | 7篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 6篇 |
1972年 | 3篇 |
1971年 | 3篇 |
1970年 | 5篇 |
1969年 | 3篇 |
1968年 | 3篇 |
1967年 | 3篇 |
1965年 | 1篇 |
1963年 | 1篇 |
1958年 | 1篇 |
排序方式: 共有242条查询结果,搜索用时 0 毫秒
241.
Botelho-Júnior S Siqueira-Júnior CL Jardim BC Machado OL Neves-Ferreira AG Perales J Jacinto T 《Journal of agricultural and food chemistry》2008,56(20):9404-9409
This work investigates the effect of methyl jasmonte (MeJa), mechanical wounding, and herbivory caused by larval feeding of a specialist insect ( Agraulis vanillae vanillae) upon trypsin inhibitory activity in passion fruit leaves. Despite the fact that all treatments caused accumulation of trypsin inhibitors (TIs), higher levels were observed in MeJa treated leaves when plants were assayed 24 and 48 h after stimulus. Concerning both mechanically injured plants and attacked ones, a systemic induction was observed. Partially purified inhibitors from MeJa exposed plants were further characterized by X-ray film contact print technique and N-terminal sequence. Such analysis indicated that the TIs identified belong to the Kunitz family. Moreover, the partially purified inhibitors strongly inhibited trypsin-like digestive enzymes from sugar cane stalk borer ( Diatraea saccharalis) in vitro. Our results further support the protective function of wound-inducible trypsin inhibitors and their potential as tools to improve important crop species against insect predation through genetic engineering. 相似文献
242.
Global patterns of influenza a virus in wild birds 总被引:1,自引:0,他引:1
Olsen B Munster VJ Wallensten A Waldenström J Osterhaus AD Fouchier RA 《Science (New York, N.Y.)》2006,312(5772):384-388
The outbreak of highly pathogenic avian influenza of the H5N1 subtype in Asia, which has subsequently spread to Russia, the Middle East, Europe, and Africa, has put increased focus on the role of wild birds in the persistence of influenza viruses. The ecology, epidemiology, genetics, and evolution of pathogens cannot be fully understood without taking into account the ecology of their hosts. Here, we review our current knowledge on global patterns of influenza virus infections in wild birds, discuss these patterns in the context of host ecology and in particular birds' behavior, and identify some important gaps in our current knowledge. 相似文献