全文获取类型
收费全文 | 840篇 |
免费 | 54篇 |
国内免费 | 1篇 |
专业分类
林业 | 52篇 |
农学 | 39篇 |
基础科学 | 1篇 |
127篇 | |
综合类 | 73篇 |
农作物 | 46篇 |
水产渔业 | 95篇 |
畜牧兽医 | 407篇 |
园艺 | 11篇 |
植物保护 | 44篇 |
出版年
2023年 | 2篇 |
2022年 | 8篇 |
2021年 | 9篇 |
2020年 | 6篇 |
2019年 | 22篇 |
2018年 | 16篇 |
2017年 | 21篇 |
2016年 | 22篇 |
2015年 | 23篇 |
2014年 | 18篇 |
2013年 | 45篇 |
2012年 | 44篇 |
2011年 | 61篇 |
2010年 | 28篇 |
2009年 | 19篇 |
2008年 | 41篇 |
2007年 | 42篇 |
2006年 | 49篇 |
2005年 | 39篇 |
2004年 | 35篇 |
2003年 | 42篇 |
2002年 | 33篇 |
2001年 | 32篇 |
2000年 | 41篇 |
1999年 | 31篇 |
1998年 | 6篇 |
1997年 | 9篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1992年 | 15篇 |
1991年 | 9篇 |
1990年 | 15篇 |
1989年 | 16篇 |
1988年 | 15篇 |
1987年 | 12篇 |
1986年 | 7篇 |
1985年 | 10篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1976年 | 5篇 |
1975年 | 2篇 |
1973年 | 3篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1970年 | 5篇 |
排序方式: 共有895条查询结果,搜索用时 203 毫秒
171.
Nakamura Masato Oritate Fumiko Yuyama Yoshito Yamaoka Masaru Dan Nguyen Phuoc Hanh Dang Vu Bich 《Paddy and Water Environment》2018,16(1):193-198
Paddy and Water Environment - In some areas of Vietnam, digested slurry from biogas digesters is discharged into canals without wastewater treatment. In order to reduce environmental pollution,... 相似文献
172.
173.
T Nakamura K Kiryu N Machida T Iwata M Oikawa M Kaneko 《American journal of veterinary research》1992,53(3):288-290
The common, external, and internal carotid and occipital arteries were examined histologically at the trifurcation of the common carotid arteries in 13 Thoroughbred foals (0 to 30 days old) and 64 Thoroughbred adults (2 to 4 years old). Calcification in the media of the common carotid and external carotid arteries was observed in 3 of the 13 foals and in 30 of the 64 adult horses. Calcification resembled that seen in M?nckeberg's arteriosclerosis in human beings, the cause of which is unknown. 相似文献
174.
175.
176.
177.
Y Nakamura S Kawazu T Minami 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(1):73-79
Protein composition was compared and epitopes were analyzed among the isolates of Anaplasma centrale and A. marginale by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblotting using bovine antisera and monoclonal antibodies, and enzyme-linked immunosorbent assay. Common and unique proteins were found among the isolates. All isolates tested had a major surface protein with an apparent molecular weight of 38 to 40 kilodalton which had slight molecular size variations between species. This protein was also a dominant immunogen to the host. At least two species-common epitopes, one of which might contain carbohydrate(s), were present on the major surface protein. One species-specific epitope was identified on the major surface protein of A. marginale isolates. 相似文献
178.
T Nakao K Sato T Nakamura K Taguchi M Moriyoshi K Kawata 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(1):19-22
To determine whether beta 2-adrenergic stimulant (clenbuterol) would exhibit beneficial effects upon the elimination of night-time calving, 42 Holstein Friesian cows and heifers at the first stage of labour were injected intramuscularly twice with clenbuterol; 300 micrograms at 18:00 and 210 micrograms at 22:00. Other 26 cows and heifers of the same breed at the first stage of labour at 18:00 were not treated and served as controls. All of the treated animals, but one, calved after 5:00 in the next morning, showing a peak of parturition between 5:00 and 10:00. In contrast to this, 42% of the control animals calved at night between 22:00 and 5:00. Thus, the double administrations of clenbuterol were shown to be effective for eliminating night-time calving. The cows treated with clenbuterol tended to show lower incidences of dystocia and retained placenta and a higher first insemination conception rate than the control animals. No adverse effects of the treatment on the viability of newborn calves and milk yields were observed. 相似文献
179.
Demonstration of the correlation of a 36-megadalton Salmonella serovar enteritidis plasmid to virulence in mice by reintroduction of the plasmid 总被引:2,自引:0,他引:2
180.