全文获取类型
收费全文 | 844篇 |
免费 | 38篇 |
专业分类
林业 | 16篇 |
农学 | 27篇 |
基础科学 | 1篇 |
55篇 | |
综合类 | 86篇 |
农作物 | 37篇 |
水产渔业 | 49篇 |
畜牧兽医 | 565篇 |
园艺 | 9篇 |
植物保护 | 37篇 |
出版年
2022年 | 6篇 |
2021年 | 11篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 6篇 |
2016年 | 12篇 |
2015年 | 8篇 |
2014年 | 9篇 |
2013年 | 27篇 |
2012年 | 23篇 |
2011年 | 30篇 |
2010年 | 21篇 |
2009年 | 18篇 |
2008年 | 27篇 |
2007年 | 23篇 |
2006年 | 35篇 |
2005年 | 37篇 |
2004年 | 35篇 |
2003年 | 28篇 |
2002年 | 37篇 |
2001年 | 26篇 |
2000年 | 32篇 |
1999年 | 31篇 |
1998年 | 27篇 |
1997年 | 21篇 |
1996年 | 19篇 |
1995年 | 11篇 |
1994年 | 14篇 |
1993年 | 13篇 |
1992年 | 15篇 |
1991年 | 20篇 |
1990年 | 22篇 |
1989年 | 17篇 |
1988年 | 16篇 |
1987年 | 11篇 |
1986年 | 22篇 |
1985年 | 16篇 |
1983年 | 11篇 |
1982年 | 6篇 |
1981年 | 6篇 |
1979年 | 7篇 |
1978年 | 5篇 |
1975年 | 5篇 |
1974年 | 6篇 |
1973年 | 4篇 |
1972年 | 9篇 |
1971年 | 4篇 |
1970年 | 8篇 |
1968年 | 4篇 |
1966年 | 5篇 |
排序方式: 共有882条查询结果,搜索用时 15 毫秒
1.
2.
J A Ellis H Russell J Cavender T R Haven 《Veterinary immunology and immunopathology》1992,34(1-2):35-45
Cattle were immunized with vaccines containing modified-live or inactivated bovine respiratory syncytial virus (BRSV) and serum antibody responses were analyzed. Compared with preinculation values, at Day 14 after two biweekly immunizations with modified-live or inactivated vaccines there were significant increases in BRSV-specific titers in the sera of cattle that received both types of vaccines, as determined by a whole cell ELISA. Using a blocking ELISA and radioimmune precipitation it was determined that there was recognition of the fusion (F) protein by antibodies from cattle that received both types of BRSV antigens: however, virus neutralization assays revealed that only cattle that received modified live virus, either in monovalent or polyvalent vaccines, developed neutralizing antibodies to BRSV after two immunizations. These results indicate that inactivation of BRSV can lead to a dissociation between serological recognition of the F protein and virus neutralization in vaccinated cattle. 相似文献
3.
H E Kennedy S J McCullough D Graham J Cassidy F E Malone W A Ellis 《Journal of veterinary diagnostic investigation》2001,13(1):30-35
Two serological tests (indirect immunofluorescence and enzyme-linked immunosorbent assay) were developed for the detection of fetal antibody to Chlamydia psittaci. Fetal blood and thoracic fluid from 126 field cases of suspected ovine chlamydial abortion were examined using both tests. Placenta and fetal tissues (lung, liver, and kidney) from the same animals were also examined by the following conventional diagnostic methods: isolation in McCoy cells, detection of chlamydial lipopolysaccharide (LPS), modified Ziehl-Nielsen staining, and direct fluorescent antibody staining of chlamydia in frozen cryostat sections. Seventy cases were positive by fetal serology, and of these, 68 were also positive by isolation and/or LPS detection. The remaining 56 cases had negative fetal serology, and of these, 39 were positive by isolation and/or LPS detection. Results indicate that fetal serology, although less sensitive than either isolation in McCoy cells or detection of chlamydial LPS antigen, may be of particular use when placenta is not available. 相似文献
4.
A strain of Yersinia enterocolitica of O serogroup 6,30 isolated from the liver of an aborted ovine fetus was inoculated intravenously into a group of pregnant ewes at about 90 days gestation and produced placentitis with abortion or delivery of infected lambs about 50 days later. Y. enterocolitica of the same serogroup was recovered from the necrotic placental cotyledons and most other fetal tissues and could be isolated from vaginal discharges of the ewes for a least 2 weeks after abortion. Histological changes were consistent with an acute bacterial necrotizing placentitis and systemic infection of the fetus. Subsequent pregnancies in the ewes proceeded to term without evidence of infection. 相似文献
5.
6.
对猪轮状病毒2型(PCV2)的研究,为全球探讨断奶后多系统消瘦综合征(PMWS)的特殊问题,提供了许多答案。但是本文提出了一些还需要特别注意的地方 ,用以避免其可能导致的“恶果”出现。过去几年里 ,在关于断奶后多系统消瘦综合征(PMWS)、猪轮状病毒病(PCVD )全球性的探讨中 ,已经对许多关于疾病流行特点的来源和特征进行了广泛的研究。猪血清中猪轮状病毒2型 (PCV2)抗体以及猪的组织样本的检测表明 ,至少从1969年起 ,猪轮状病毒2型 (PCV2)的抗体就已经存在于猪的群体中了。现在已经确定 ,从1986年起在西班牙和英国就发现了传统的PMWS… 相似文献
7.
Individual antigens of goats 总被引:1,自引:0,他引:1
8.
对Ⅱ型猪圆环病毒的研究为与猪断奶后多系统消耗性综合征在全球爆发有关的问题提供了大量答案,但还有一些方面迫切需要引起人们的关注,以便为可能出现的梦魇般的前景准备对策. 相似文献
9.
Immunophenotype of pulmonary cellular infiltrates in sheep with visceral caseous lymphadenitis 总被引:1,自引:0,他引:1
J A Ellis 《Veterinary pathology》1988,25(5):362-368
Pulmonary lesions associated with Corynebacterium ovis were analyzed with an indirect immunoperoxidase staining technique using monoclonal antibodies. The predominant cells in abscess walls and surrounding lung parenchyma were large macrophages which expressed major histocompatibility complex (MHC) class II molecules on their surfaces. T lymphocytes were prominent in the same sites in the naturally occurring lesions, and SBU-T4-positive ("helper/inducer") cells were the major subset of lymphocytes (mean T4/T8 ratio = 3.5). B lymphocytes and granulocytes comprised minor populations of infiltrating cells. These results implicate activated macrophages and MHC class II-restricted T lymphocytes in the pathogenesis of established C. ovis infections in sheep. 相似文献
10.
Heather Bixler Christine Ellis 《Veterinary Clinics of North America: Exotic Animal Practice》2004,7(2):227-55, v
Convivial and playful, the ferret has cohabited with humans for hundreds of years. Maintenance of this mustelid's health and quality of life is paramount for the endurance of the human-animal bond. This review article for veterinary care givers, veterinarians, and staff, encompasses discussions on: husbandry, clinical techniques, prevalent diseases, history taking, physical examination, vaccination, and pain recognition. This article also enables the veterinary community to contribute to the care and welfare of ferret patients by offering facts to distinguish these animals from dogs and cats. 相似文献