全文获取类型
收费全文 | 328篇 |
免费 | 29篇 |
专业分类
林业 | 1篇 |
农学 | 3篇 |
10篇 | |
综合类 | 80篇 |
农作物 | 4篇 |
水产渔业 | 8篇 |
畜牧兽医 | 243篇 |
园艺 | 4篇 |
植物保护 | 4篇 |
出版年
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 9篇 |
2017年 | 7篇 |
2016年 | 15篇 |
2015年 | 4篇 |
2014年 | 8篇 |
2013年 | 26篇 |
2012年 | 2篇 |
2011年 | 6篇 |
2010年 | 12篇 |
2009年 | 7篇 |
2008年 | 8篇 |
2007年 | 3篇 |
2006年 | 9篇 |
2005年 | 4篇 |
2004年 | 8篇 |
2003年 | 3篇 |
2002年 | 7篇 |
2001年 | 20篇 |
2000年 | 7篇 |
1999年 | 13篇 |
1998年 | 13篇 |
1997年 | 14篇 |
1996年 | 13篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 8篇 |
1992年 | 5篇 |
1991年 | 7篇 |
1990年 | 8篇 |
1989年 | 14篇 |
1988年 | 10篇 |
1986年 | 2篇 |
1985年 | 5篇 |
1974年 | 2篇 |
1970年 | 4篇 |
1969年 | 3篇 |
1967年 | 2篇 |
1915年 | 2篇 |
1913年 | 3篇 |
1912年 | 2篇 |
1909年 | 2篇 |
1908年 | 4篇 |
1907年 | 2篇 |
1905年 | 2篇 |
1904年 | 3篇 |
1901年 | 3篇 |
1900年 | 3篇 |
1898年 | 2篇 |
排序方式: 共有357条查询结果,搜索用时 500 毫秒
31.
Akabane disease in sheep 总被引:1,自引:0,他引:1
Perinatal lamb mortality, associated with malformations of the CNS due to Akabane viral infection, occurred in 4 of 9 flocks of ewes lambing on 3 farms between 26 May and 14 November, 1976. Cases were restricted to ewes conceiving prior to the second week of March and lambing between 26 May and 19 July. As judged by seroconversion in sentinel flocks on 2 of the farms, field infection with Akabane virus occurred mainly between mid-February and mid-April. Malformations of the CNS occurred in 42.5%, 51.2%, 100% and 31.0% of the dead lambs examined in the affected flocks respectively. Prevalence in the 4 affected flocks, expressed as the proportion of ewes lambing which delivered at least one malformed foetus, was 6.1%, 8.4%, 88.9% and 5.7% respectively. Lamb mortality due to malformations of the CNS was 7.1%, 5.5%, 92.3% and 5.7% of lambs born. Age-specific prevalence was calculated for 3 of the 4 flocks and 2-year-old ewes accounted for 71.4% and 76.9% of total cases respectively in 2 flocks, whereas in one flock malformations occurred at equivalent frequencies throughout several older age groups. Birthweights of affected lambs were usually significantly lighter than those of unaffected lambs of similar sex and birth-type, and their mean duration of gestation was slightly, and significantly, prolonged. Micrencephaly (88.1% of cases) and hydrocephalus (68.7% of cases) were the outstanding pathological features of the malformations with hydranencephaly, microgyria, porencephaly and attenuation of the spinal cord occurring at much lower frequencies.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
32.
33.
34.
35.
36.
37.
38.
39.
P.G. Davenport B.V.Sc. 《New Zealand veterinary journal》2013,61(5):138-139
Extract For many years bloat has been a major problem of dairy herds in the Bay of Plenty, but no known attempt has been made to assess the magnitude of this problem. It was therefore decided to carry out a simple survey in this area to try to gauge the extent of both bloat incidence and losses due to bloat. It was felt that from such a survey the information gained would indicate whether or not further research into the problem was warranted. 相似文献
40.
CASE HISTORY: A 14-year-old neutered male Bearded Collie was presented with a history of recurrent, intermittent urinary incontinence of 7 years duration. CLINICAL FINDINGS: A large, firm, non-painful mass was found in the mid-abdominal region on palpation. Ultrasonography of the mass revealed a compartmentalised structure with mixed echogenicity, and which did not appear to be associated with any of the abdominal organs. Ultrasound-guided fine needle aspirates contained several clusters of epithelial cells with cytological features of hepatocytes. At exploratory laparotomy, the mass was found in the gastrosplenic ligament within the greater omentum. PATHOLOGICAL FINDINGS AND DIAGNOSIS: Histopathologically, the mass consisted of sheets of hepatocytes, but without the characteristic hepatic architecture. The cells showed moderate variation in nuclear size and were sometimes binucle- ate. A diagnosis of hepatocellular carcinoma (HCC) in the mesentery was made. CLINICAL RELEVANCE: The presence of ectopic hepatic tissue has been reported rarely in man and cats, but not in the dog. Neoplastic transformation of ectopic hepatic tissue is seen in man. This is the first report of the presentation, clinical findings and treatment of a dog with ectopic HCC. 相似文献