全文获取类型
收费全文 | 859篇 |
免费 | 97篇 |
国内免费 | 32篇 |
出版年
2023年 | 4篇 |
2022年 | 7篇 |
2021年 | 15篇 |
2020年 | 15篇 |
2019年 | 12篇 |
2018年 | 33篇 |
2017年 | 13篇 |
2016年 | 34篇 |
2015年 | 40篇 |
2014年 | 39篇 |
2013年 | 61篇 |
2012年 | 63篇 |
2011年 | 49篇 |
2010年 | 44篇 |
2009年 | 45篇 |
2008年 | 47篇 |
2007年 | 43篇 |
2006年 | 48篇 |
2005年 | 28篇 |
2004年 | 24篇 |
2003年 | 23篇 |
2002年 | 21篇 |
2001年 | 25篇 |
2000年 | 13篇 |
1999年 | 23篇 |
1998年 | 18篇 |
1997年 | 17篇 |
1996年 | 8篇 |
1995年 | 4篇 |
1994年 | 10篇 |
1992年 | 17篇 |
1991年 | 8篇 |
1990年 | 13篇 |
1989年 | 8篇 |
1988年 | 8篇 |
1987年 | 12篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1982年 | 8篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1978年 | 3篇 |
1977年 | 14篇 |
1974年 | 4篇 |
1973年 | 4篇 |
1971年 | 4篇 |
1958年 | 3篇 |
1955年 | 3篇 |
1949年 | 5篇 |
排序方式: 共有988条查询结果,搜索用时 15 毫秒
981.
982.
983.
984.
985.
Jorge Ari Noriega Kevin D. Floate François Génier Chris A.M. Reid Bert Kohlmann Finbarr G. Horgan Adrian L.V. Davis Shaun A. Forgie Carlos Aguilar Mario G. Ibarra Fernando Vaz-de-Mello Stefano Ziani Jorge M. Lobo 《Entomologia Experimentalis et Applicata》2020,168(10):766-782
The establishment of cattle ranches throughout the world has prompted the release of dung beetles as biological control agents that reduce pasture fouling and control dung-breeding flies. One of these beetles, Digitonthophagus gazella (Fabricius) (Coleoptera: Scarabaeidae), that is native to southeast Africa, has been introduced into the Americas, Australia, and New Zealand. Distribution records for this species have been used to develop climate models of potential future establishment. Recent studies, however, identify D. gazella as a complex of seven species. Taking into account this revision, and the clear identification of the records belonging to the actual D. gazella, we developed environmental models to identify factors that have contributed to the establishment of this species across regions and habitats. We compared the environmental conditions of D. gazella in its native range against those in the regions where the species has or has not established. Our results indicate that D. gazella is still absent in certain parts of Central and South America and parts of Africa where it could potentially establish. We speculate that its distribution in Africa is limited by competitive exclusion. The introduction of D. gazella in America is relatively recent, such that the full extent of its distribution has probably yet to be realized. In Australia and North America, D. gazella is present in regions not predicted according to its native environmental conditions. This discrepancy may reflect a lack of competitive exclusion, phenotypic plasticity, and/or genetic adaptation. Our analyses suggest that the species has the ability to adapt to a wide range of environmental conditions that are extremely different from those in their native region. The species represents a useful case study to indicate that an introduced species may expand its realized niche beyond what is expected based on apparent environmental limits in the species native range. 相似文献
986.
987.
Synthesis and secretion of volatile short‐chain fatty acids in Triatoma infestans infected with Beauveria bassiana
下载免费PDF全文
![点击此处可从《Medical and veterinary entomology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
L. S. Lobo J. R. Girotti S. J. Mijailovsky É. K. K. Fernandes C. Luz N. Pedrini 《Medical and veterinary entomology》2018,32(3):358-364
Physically disturbed Triatoma infestans (Hemiptera: Reduviidae) adults, as well as adults of other Chagas' disease vectors, secrete a mix of volatile organic compounds (VOCs) with alarm and possible sexual and defence functions. The aim of the present research was to test whether infection with the entomopathogenic fungus Beauveria bassiana (Ascomycota: Hypocreales: Clavicipitaceae) has an effect on VOC secretion in disturbed T. infestans and on the expression of two genes (Ti‐brnq and Ti‐bckdc) potentially involved in VOC biosynthesis. The volatiles released by insects at different time periods after fungal treatment were identified and their relative amounts measured. Isobutyric acid was the most abundant volatile found in both healthy and fungus‐infected insects and underwent no significant relative changes through the infection process. The secretion of propionic acid, however, was significantly higher at 1–4 days post‐infection (d.p. i.) compared with that in controls. A slight induction of both Ti‐brnq and Ti‐bckdc genes was found by real‐time polymerase chain reaction at 4 d.p. i., with expression values reaching up to three‐fold those in controls. The early stages of fungal infection seem to affect the composition of the alarm pheromone by changing the expression pattern of both genes analysed. These results help to elucidate the impact of fungal infections on the chemical ecology of triatomine bugs. 相似文献
988.