全文获取类型
收费全文 | 15472篇 |
免费 | 3773篇 |
国内免费 | 3篇 |
专业分类
林业 | 1012篇 |
农学 | 801篇 |
基础科学 | 74篇 |
3831篇 | |
综合类 | 258篇 |
农作物 | 553篇 |
水产渔业 | 3198篇 |
畜牧兽医 | 7349篇 |
园艺 | 172篇 |
植物保护 | 2000篇 |
出版年
2024年 | 17篇 |
2023年 | 80篇 |
2022年 | 132篇 |
2021年 | 363篇 |
2020年 | 684篇 |
2019年 | 1167篇 |
2018年 | 1257篇 |
2017年 | 1289篇 |
2016年 | 1293篇 |
2015年 | 1083篇 |
2014年 | 1131篇 |
2013年 | 1486篇 |
2012年 | 1139篇 |
2011年 | 1089篇 |
2010年 | 931篇 |
2009年 | 554篇 |
2008年 | 785篇 |
2007年 | 631篇 |
2006年 | 552篇 |
2005年 | 528篇 |
2004年 | 484篇 |
2003年 | 422篇 |
2002年 | 378篇 |
2001年 | 273篇 |
2000年 | 311篇 |
1999年 | 189篇 |
1998年 | 42篇 |
1997年 | 53篇 |
1996年 | 35篇 |
1995年 | 26篇 |
1994年 | 20篇 |
1993年 | 27篇 |
1992年 | 58篇 |
1991年 | 43篇 |
1990年 | 48篇 |
1989年 | 50篇 |
1988年 | 37篇 |
1987年 | 39篇 |
1986年 | 48篇 |
1985年 | 49篇 |
1984年 | 36篇 |
1983年 | 36篇 |
1982年 | 21篇 |
1979年 | 32篇 |
1978年 | 36篇 |
1977年 | 32篇 |
1974年 | 28篇 |
1973年 | 47篇 |
1972年 | 30篇 |
1971年 | 25篇 |
排序方式: 共有10000条查询结果,搜索用时 562 毫秒
41.
F.J. López-Escudero C. del Río J.M. Caballero M.A. Blanco-López 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(1):79-85
Resistance of 23 important olive cultivars to Verticillium dahliae has been evaluated in four experiments under controlled conditions. Nine-month-old nursery olive plants were inoculated with a cotton non-defoliating (ND) (V4) or a cotton defoliating (D) (V117) isolate of V. dahliae. Resistance was evaluated by assessing symptom severity using a 0–4 rating scale and estimating the area under disease progress curves. The percentage of plants killed and of those which recovered from the disease were used as additional parameters for including a particular cultivar into a defined category. Most of the evaluated cultivars were susceptible, although at different levels, to both isolates of V. dahliae. All cultivars were more susceptible to the D pathotype than to the ND one. A group of 11 cultivars, including several important Spanish cultivars, were susceptible or extremely susceptible to both pathotypes of V. dahliae. A second group showed differences of resistance depending on the pathotype used. They were susceptible or extremely susceptible to the D pathotype but resistant or moderately susceptible to the ND one. Finally, 'Frantoio', 'Oblonga' and 'Empeltre' were moderately susceptible to the D isolate of V. dahliae and resistant to the ND one. The resistance of 'Empeltre' was evident by the plant ability to recover from infection with either isolates. 'Empeltre' is considered to be a valuable cultivar for inclusion in breeding programmes for resistance to Verticillium wilt. 相似文献
42.
Ultrastructure of the tubular glands in the isthmus region of the oviduct in laying and natural moulting commercial egg‐type chickens
下载免费PDF全文
![点击此处可从《Anatomia, histologia, embryologia》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Mary‐Cathrine Nyasha Madekurozwa Mike M. Mpango 《Anatomia, histologia, embryologia》2018,47(5):493-497
The study investigated the ultrastructural characteristics of tubular gland and duct cells, as well as luminal gland cells in the isthmus region of the oviduct of laying and natural moulting hens. Tubular glands in laying birds were composed of type 1 and 2 cells. Based on the preponderance of each cell type, in relation to the location of a developing egg in the oviduct of the domestic fowl, these gland cells may represent different functional states of the same cell. The findings of the study on natural moulting birds suggest that autophagy is a process confined to the early stages of degeneration, while necrosis occurs in the terminal stages. 相似文献
43.
44.
Fracture of the medial intercondylar eminence of the tibia in horses treated by arthroscopic fragment removal (21 horses)
下载免费PDF全文
![点击此处可从《Equine veterinary journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
45.
46.
An improved vitrification protocol for equine immature oocytes,resulting in a first live foal
下载免费PDF全文
![点击此处可从《Equine veterinary journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
47.
48.
49.
50.