全文获取类型
| 收费全文 | 145篇 |
| 免费 | 18篇 |
专业分类
| 农学 | 1篇 |
| 基础科学 | 1篇 |
| 7篇 | |
| 综合类 | 24篇 |
| 农作物 | 7篇 |
| 水产渔业 | 6篇 |
| 畜牧兽医 | 114篇 |
| 园艺 | 2篇 |
| 植物保护 | 1篇 |
出版年
| 2022年 | 1篇 |
| 2020年 | 4篇 |
| 2019年 | 1篇 |
| 2018年 | 2篇 |
| 2017年 | 3篇 |
| 2016年 | 1篇 |
| 2015年 | 4篇 |
| 2014年 | 1篇 |
| 2013年 | 7篇 |
| 2012年 | 5篇 |
| 2011年 | 10篇 |
| 2010年 | 4篇 |
| 2009年 | 7篇 |
| 2008年 | 13篇 |
| 2007年 | 7篇 |
| 2006年 | 3篇 |
| 2005年 | 5篇 |
| 2004年 | 4篇 |
| 2003年 | 4篇 |
| 2002年 | 5篇 |
| 2001年 | 5篇 |
| 2000年 | 6篇 |
| 1999年 | 4篇 |
| 1998年 | 6篇 |
| 1997年 | 10篇 |
| 1996年 | 7篇 |
| 1995年 | 2篇 |
| 1994年 | 3篇 |
| 1992年 | 5篇 |
| 1991年 | 8篇 |
| 1990年 | 3篇 |
| 1989年 | 1篇 |
| 1988年 | 6篇 |
| 1985年 | 1篇 |
| 1984年 | 1篇 |
| 1976年 | 1篇 |
| 1969年 | 1篇 |
| 1957年 | 1篇 |
| 1956年 | 1篇 |
排序方式： 共有163条查询结果，搜索用时 718 毫秒
1.
Pringle JK Ducharme NG Baird JD 《The Canadian veterinary journal. La revue veterinaire canadienne》1990,31(1):26-30
Ureterovesicular anastomosis resulted in resolution of the clinical signs of urinary incontinence in three horses with unilateral ectopic ureter. Follow-up of two of the horses ten months and three years later indicated no further urinary tract problems; the third horse died four days after surgery from intestinal infarction.
Diagnosis can be readily confirmed by antegrade or retrograde ureterography, or endoscopic visualization of the ectopic ureteral openings. Nephrectomy appears indicated in cases of unilateral ectopic ureter with associated ipsilateral urinary tract infection or hydronephrosis, providing the contralateral kidney has normal function. Ureterovesicular anastomosis appears to be indicated in the management of unilateral ectopic ureters in the absence of ascending urinary tract infection or hydronephrosis, and in cases of bilateral ectopic ureters.
相似文献2.
3.
4.
Recent quantitative site-based monitoring and qualitative aerial and ground traverses provide contrasting assessments of the
health of much of the arid shrublands of Western Australia extensively grazed by livestock (‘rangelands’). Although these
results seem incompatible, we explain the apparent contradictions based on landscape succession processes operating at multiple
levels of ecological organisation. Specifically, we suggest that the intact areas in which site-based monitoring is conducted
are contracting as catchment canalisation and desiccation increase. However, the impacts of these processes have not yet become
manifest at the site scale. The site-based system addresses important regional questions. These relate to the large, relatively
intact areas away from most active surface flows, which should be a focus for resource conservation, given practical limits
to repairing widespread degradation with low management inputs. We provide a complementary set of questions to provide a more
comprehensive audit of rangeland dynamics in the context of underlying hierarchical landscape patterns and processes that
might threaten intact areas. We recognise the need to match questions and levels of ecological organisation and the implications
these have for sampling. We also recognise the difficulty in producing concise statements of change for clients when reporting
on complex ecological issues and processes. Without a clearly articulated, and well understood, hierarchical model of pattern
and process within which apparently contradictory findings can be reported meaningfully, policy makers may be confused by
the results, with the consequent risk of policy inaction. 相似文献
5.
Objective To measure the prevalence of megabacteria in budgerigar-breeding colonies and to evaluate possible methods to reduce the prevalence.
Design A monitoring study over several years.
Sample population Two budgerigar ( Melopsittacus undulatus ) colonies with over 300 birds each.
Procedure The prevalence of megabacteria in the faeces in two budgerigar breeding colonies, colony 1 and 2, was determined by faecal examination of each bird. Following an initial survey (1990), most of the birds that were scored 2+ or more were culled and a management practice was implemented to discriminate against positive birds. Consecutive yearly surveys (1991, 1992) were conducted on the young birds bred in these colonies. The prevalence of megabacteria in colony 2 was also evaluated in 1994 and 1996 after all the birds were treated with amphotericin B administered in drinking water.
Results The prevalence of megabacteria in the two colonies was significantly (P < 0.001) different. Overall the prevalence of megabacteria adjusted for colony differences was significantly higher (P < 0.025) in males compared to females. Age was not an influencing factor. After the initial survey, the prevalence in the offspring did not significantly (P > 0.05) decrease in the following two annual breeding seasons but by inference it did significantly decrease after amphotericin B treatment.
Conclusion The practice of culling most birds with more megabacteria in faeces and discriminating against positive birds when selecting birds for breeding or culling birds on show quality does not decrease megabacteria prevalence in the offspring. However, a reduction in prevalence does occur with administration of amphotericin B. Birds may have amphotericin B-resistant organisms and these birds need to be identified and culled. 相似文献
Design A monitoring study over several years.
Sample population Two budgerigar ( Melopsittacus undulatus ) colonies with over 300 birds each.
Procedure The prevalence of megabacteria in the faeces in two budgerigar breeding colonies, colony 1 and 2, was determined by faecal examination of each bird. Following an initial survey (1990), most of the birds that were scored 2+ or more were culled and a management practice was implemented to discriminate against positive birds. Consecutive yearly surveys (1991, 1992) were conducted on the young birds bred in these colonies. The prevalence of megabacteria in colony 2 was also evaluated in 1994 and 1996 after all the birds were treated with amphotericin B administered in drinking water.
Results The prevalence of megabacteria in the two colonies was significantly (P < 0.001) different. Overall the prevalence of megabacteria adjusted for colony differences was significantly higher (P < 0.025) in males compared to females. Age was not an influencing factor. After the initial survey, the prevalence in the offspring did not significantly (P > 0.05) decrease in the following two annual breeding seasons but by inference it did significantly decrease after amphotericin B treatment.
Conclusion The practice of culling most birds with more megabacteria in faeces and discriminating against positive birds when selecting birds for breeding or culling birds on show quality does not decrease megabacteria prevalence in the offspring. However, a reduction in prevalence does occur with administration of amphotericin B. Birds may have amphotericin B-resistant organisms and these birds need to be identified and culled. 相似文献
6.
7.
8.
9.
Objective To estimate the changes in productivity and profitability in a group of wool-growing farms as they adopted major recommendations from agricultural and veterinary studies.
Farms Four wool-growing farms in south western Victoria were selected from the clients of the Mackinnon Project, a farm consultancy service run from the University of Melbourne. Each farm had closely followed recommended procedures, kept comprehensive financial and physical records and had been clients for at least 5 years. The comparison group was the South Western Victoria Monitor Farm Project (SWVMFP), about 45 farms in the same region as the study farms that were monitored annually by Agriculture Victoria.
Procedure For a 7-year period, the financial and physical performance of both groups of farms was estimated. Stocking rate, wool production, gross farm income, farm operating costs, net farm income and return on assets were compared.
Results Mean gross farm income of the four study farms steadily rose from 86% of the average SWVMFP farm before the adoption of recommendations to an average of 155%. During the same period, net farm income rose from 70% to 207% of the average of the SWVMFP. Return on asset of the four farms rose irregularly from 26% to 145% of the average of the SWVMFP. Farm operating costs on the four farms were higher than for the SWVMFP group, but the ratio of costs remained relatively constant.
Conclusion The adoption of proven research results was associated with large increases in net farm income. An increase in gross income, rather than a reduction in costs was the main reason for this. Research results offer a way to increase the financial viability of wool-growing farmers, many of whom are currently unable to maintain their lifestyle, resources and infrastructure. 相似文献
Farms Four wool-growing farms in south western Victoria were selected from the clients of the Mackinnon Project, a farm consultancy service run from the University of Melbourne. Each farm had closely followed recommended procedures, kept comprehensive financial and physical records and had been clients for at least 5 years. The comparison group was the South Western Victoria Monitor Farm Project (SWVMFP), about 45 farms in the same region as the study farms that were monitored annually by Agriculture Victoria.
Procedure For a 7-year period, the financial and physical performance of both groups of farms was estimated. Stocking rate, wool production, gross farm income, farm operating costs, net farm income and return on assets were compared.
Results Mean gross farm income of the four study farms steadily rose from 86% of the average SWVMFP farm before the adoption of recommendations to an average of 155%. During the same period, net farm income rose from 70% to 207% of the average of the SWVMFP. Return on asset of the four farms rose irregularly from 26% to 145% of the average of the SWVMFP. Farm operating costs on the four farms were higher than for the SWVMFP group, but the ratio of costs remained relatively constant.
Conclusion The adoption of proven research results was associated with large increases in net farm income. An increase in gross income, rather than a reduction in costs was the main reason for this. Research results offer a way to increase the financial viability of wool-growing farmers, many of whom are currently unable to maintain their lifestyle, resources and infrastructure. 相似文献
10.
A 19-year-old horse that was one of a group of six horses infected experimentally with Anaplasma phagocytophilum for a study of the pathogenesis of equine granulocytic ehrlichiosis died suddenly two days after first showing clinical signs of disease. The clinical signs and laboratory findings observed before its death were similar to all those of the other infected horses, and to previous reports of this disease. A postmortem examination revealed widespread haemorrhaging in its internal organs, and vasculitis and thrombosis in the kidneys. These changes are consistent with disseminated intravascular coagulation, which has previously been reported in human beings infected with the presumably identical agent of human granulocytic ehrlichiosis. 相似文献