全文获取类型
收费全文 | 459篇 |
免费 | 15篇 |
专业分类
林业 | 135篇 |
农学 | 12篇 |
103篇 | |
综合类 | 36篇 |
农作物 | 16篇 |
水产渔业 | 22篇 |
畜牧兽医 | 123篇 |
园艺 | 7篇 |
植物保护 | 20篇 |
出版年
2020年 | 7篇 |
2019年 | 6篇 |
2018年 | 8篇 |
2017年 | 6篇 |
2016年 | 10篇 |
2015年 | 8篇 |
2014年 | 12篇 |
2013年 | 11篇 |
2012年 | 18篇 |
2011年 | 30篇 |
2010年 | 10篇 |
2009年 | 15篇 |
2008年 | 28篇 |
2007年 | 20篇 |
2006年 | 20篇 |
2005年 | 17篇 |
2004年 | 17篇 |
2003年 | 22篇 |
2002年 | 11篇 |
2001年 | 7篇 |
2000年 | 4篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1977年 | 4篇 |
1975年 | 3篇 |
1974年 | 5篇 |
1972年 | 6篇 |
1969年 | 3篇 |
1968年 | 3篇 |
1967年 | 5篇 |
1966年 | 3篇 |
1965年 | 4篇 |
1962年 | 3篇 |
1956年 | 4篇 |
1948年 | 7篇 |
1941年 | 3篇 |
1934年 | 3篇 |
1933年 | 3篇 |
1932年 | 12篇 |
1927年 | 7篇 |
1919年 | 6篇 |
1918年 | 5篇 |
1915年 | 4篇 |
1904年 | 5篇 |
1902年 | 3篇 |
排序方式: 共有474条查询结果,搜索用时 578 毫秒
51.
Z E Kowalski R C Franz W J Coetzee W H Giesecke 《The Onderstepoort journal of veterinary research》1984,51(3):209-212
Using the composite fibrin plates method, plasminogen activator (PA) activity was found in secretions from clinically normal, mastitic, lactating and dried-off udders of dairy cows. The possible involvement of the fibrinolytic system in the physiology and pathology of the bovine mammary gland is discussed. 相似文献
52.
53.
54.
Conraths FJ Köhler H Werner O Beer M Depner KR Geue L Kaden V Staubach C Pötzsch C Schares G Mettenleiter TC 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(9-10):354-364
The Friedrich-Loeffler-Institut, founded in 1910 by Friedrich Loeffler, the discoverer of the first animal virus, foot-and-mouth disease virus, is the oldest virological research facility in the world. Beyond viruses, its area of competence has significantly expanded since its foundation and now also covers bacterial, parasitic and prion diseases of livestock, poultry and aquatic animals. Presently located at four sites within Germany (Insel Riems, Jena,Tübingen,Wusterhausen) the tasks of the institute as delineated in the Animal Disease Act encompass research on infectious animal diseases including zoonoses, import/export examinations, epidemiological studies in case of outbreaks of notifiable animal diseases, acting as reference laboratory for notifiable animal diseases and nationwide quality management of diagnosis of notifiable animal diseases. It is obliged to publish and maintain up-to-date diagnostic regimes for notifiable animal diseases, and it publishes a yearly report on animal health in Germany. With the increasing importance of infectious diseases of animals, in particular those potentially harmful to man (zoonoses), the Friedrich-Loeffler-Institut will be moving into new facilities including laboratories and animal facilities up to the highest biosafety level at its main site Insel Riems on the occasion of its 100th anniversary. 相似文献
55.
56.
57.
58.
Franz J. Schwinn 《Pest management science》1984,15(1):40-47
Over the past 15 years, an increasing number of ergosterol biosynthesis inhibitors (EBIs) have been introduced in crop protection as fungicides, and in medicine as fungicides and bactericides. Their spectrum of activity and their systemic properties vary widely, depending on structural elements. By their high protective and curative activity the EBIs have greatly improved the level of disease control, both in plants and in man. However, the chemical and biological potential of this group has not yet been fully explored, particularly in the field of growth regulation. 相似文献
59.
Two different techniques were tested in nine calves to describe endoscopically the visible structures of the rumen and the reticulum. Ruminoscopy using an orally introduced flexible endoscope proved to be unsatisfactory, but when the endoscope was introduced through a ruminal fistula in the left flank into the dorsal and ventral ruminal sacs, the blind sacs, ruminal pillars, the atrium of the rumen, the reticulum and the reticular groove could all be displayed effectively. Indentations of the ruminal wall caused by the left kidney, the spleen and the abomasum could be seen with the endoscope as could reticulo-ruminal contractions. The technique allowed visual evaluation of the mucosal surfaces and movement of the rumen, reticulum and reticular groove. The advantages and disadvantages of ruminoscopy in bovine medicine are discussed. 相似文献
60.
Price DC Chan CX Yoon HS Yang EC Qiu H Weber AP Schwacke R Gross J Blouin NA Lane C Reyes-Prieto A Durnford DG Neilson JA Lang BF Burger G Steiner JM Löffelhardt W Meuser JE Posewitz MC Ball S Arias MC Henrissat B Coutinho PM Rensing SA Symeonidi A Doddapaneni H Green BR Rajah VD Boore J Bhattacharya D 《Science (New York, N.Y.)》2012,335(6070):843-847