全文获取类型
收费全文 | 452篇 |
免费 | 14篇 |
专业分类
林业 | 85篇 |
农学 | 2篇 |
193篇 | |
综合类 | 41篇 |
农作物 | 15篇 |
水产渔业 | 10篇 |
畜牧兽医 | 91篇 |
园艺 | 7篇 |
植物保护 | 22篇 |
出版年
2023年 | 6篇 |
2021年 | 4篇 |
2020年 | 11篇 |
2019年 | 6篇 |
2018年 | 5篇 |
2017年 | 8篇 |
2016年 | 15篇 |
2015年 | 10篇 |
2014年 | 14篇 |
2013年 | 25篇 |
2012年 | 29篇 |
2011年 | 37篇 |
2010年 | 19篇 |
2009年 | 19篇 |
2008年 | 35篇 |
2007年 | 28篇 |
2006年 | 29篇 |
2005年 | 23篇 |
2004年 | 16篇 |
2003年 | 13篇 |
2002年 | 19篇 |
2001年 | 8篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 5篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1989年 | 2篇 |
1977年 | 2篇 |
1967年 | 1篇 |
1941年 | 2篇 |
1940年 | 3篇 |
1939年 | 3篇 |
1936年 | 1篇 |
1935年 | 1篇 |
1934年 | 1篇 |
1932年 | 2篇 |
1931年 | 3篇 |
1928年 | 3篇 |
1927年 | 4篇 |
1926年 | 7篇 |
1925年 | 1篇 |
1922年 | 2篇 |
1920年 | 2篇 |
1905年 | 2篇 |
1903年 | 1篇 |
1898年 | 4篇 |
排序方式: 共有466条查询结果,搜索用时 187 毫秒
1.
Ohne Zusammenfassung 相似文献
2.
Ohne Zusammenfassung 相似文献
3.
4.
5.
Bacterial blood culture results of 292 privately owned cats presented to the Clinic for Small Animal Medicine, Ludwig Maximilian University Munich with signs of sepsis were evaluated retrospectively. Of the blood cultures, 23% were positive. In 88%, a single bacterial species was isolated. Of all bacterial isolates, 45% were Gram-positive, 43% were Gram-negative, and 12% were obligate anaerobes. The most frequently isolated bacteria were Enterobacteriaceae, obligate anaerobic species, Staphylococcus species and Streptococcus species. Of the cats with positive blood cultures, 32% were pretreated with antibiotics. Of all bacterial isolates, 77% were susceptible to enrofloxacin, 69% to chloramphenicol, 67% to gentamicin, and 64% to amoxycillin clavulanic acid. Only enrofloxacin reached an in vitro efficacy of more than 70% against Gram-positive and more than 74% against Gram-negative bacteria. 相似文献
6.
Tappeiner Ulrike Leitinger Georg Zariņa Anita Bürgi Matthias 《Landscape Ecology》2021,36(8):2317-2328
Landscape Ecology - Landscape ecology early on developed the awareness that central objects of investigation are not stable over time and therefore the historical dimension must be included, or at... 相似文献
7.
8.
Rehbein S Holste JE Doucet MY Fenger C Paul AJ Reinemeyer CR Smith LL Yoon S Marley SE 《Veterinary therapeutics : research in applied veterinary medicine》2003,4(3):220-227
The efficacy of an oral formulation of ivermectin plus praziquantel in the reduction of nematode and cestode egg counts in horses was assessed in 273 horses under field conditions at 15 sites in North America (n = 6) and Europe (n = 9). Horses were confirmed by fecal examination to have natural infections of strongyles (100%) and tapeworms (76%). Replicates of four horses were formed at each site, and in each replicate three animals received ivermectin (0.2 mg/kg body weight) plus praziquantel (1 mg/kg body weight) oral paste and one animal remained untreated or received vehicle paste. Fecal samples were collected for fecal nematode and cestode egg counting before and 7, 8, 9, 14, 15, and 16 days after treatment. Horses treated with ivermectin plus praziquantel oral paste had significantly (P <.01) lower posttreatment strongylid and cestode egg counts (reductions of 98% or more) than controls. Combined site analyses revealed that 95% or 96% of the horses positive for cestode eggs before treatment that were treated with ivermectin plus praziquantel were negative for cestode eggs at each posttreatment fecal examination. No adverse reactions attributable to ivermectin plus praziquantel oral paste treatments were observed. The results of the studies demonstrated that ivermectin plus praziquantel paste was highly effective in reducing egg shedding by gastrointestinal nematodes and cestodes, and no adverse reactions were observed in horses treated under field conditions. 相似文献
9.
10.