全文获取类型
收费全文 | 158篇 |
免费 | 12篇 |
专业分类
林业 | 1篇 |
农学 | 1篇 |
2篇 | |
综合类 | 3篇 |
畜牧兽医 | 160篇 |
植物保护 | 3篇 |
出版年
2023年 | 2篇 |
2020年 | 2篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 2篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 7篇 |
2011年 | 5篇 |
2010年 | 2篇 |
2009年 | 8篇 |
2008年 | 1篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2004年 | 4篇 |
2003年 | 6篇 |
2002年 | 5篇 |
2001年 | 10篇 |
2000年 | 7篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1997年 | 7篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 8篇 |
1993年 | 4篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 7篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1975年 | 1篇 |
1942年 | 1篇 |
1941年 | 1篇 |
排序方式: 共有170条查询结果,搜索用时 15 毫秒
31.
32.
33.
D E Bjorling J N Chambers E A Mahaffey 《Journal of the American Veterinary Medical Association》1987,190(10):1315-1318
Epulides were diagnosed and surgically removed in 25 dogs. Histologic examination of the epulides indicated that 40% (10/25) were acanthomatous, 32% (8/25) were ossifying, and 28% (7/25) were fibromatous. Recurrence of the tumor directly resulted in the death of 2 dogs. One of these dogs died of malnutrition 13 months after removal of an ossifying epulis, and regrowth of an acanthomatous epulis that was not resected completely resulted in malnutrition and death in another dog 6 months after surgery. Malignant transformation was observed in a third dog 6 months after removal of an ossifying epulis when an osteosarcoma developed where the epulis had been removed. The range of survival was 6 to 134 months, mean survival time was 43.1 months, median survival time was 49 months, and 1-year survival rate was 92%. Satisfactory long-term tumor control was achieved by aggressive surgical treatment of epulides. 相似文献
34.
Nicola Grint BVSc DVA Diplomate ECVAA MRCVS & Alexandra Dugdale MA Vet MB DVA Diplomate ECVAA MRCVS 《Veterinary anaesthesia and analgesia》2009,36(1):63-66
Objective To compare the brightness of South American camelid venous blood to that of Equidae.
Study design Prospective clinical evaluation.
Animals Twelve South American camelids (eight llamas, four alpacas), eight horses and ponies (control group).
Methods Appropriately sized catheters were placed in the jugular vein of each animal under local anaesthesia. The blood spilt before the catheter was capped was caught on a white tile. A sample of blood was drawn for blood-gas analysis. The brightness of the blood (both on the tile and in the syringe) was matched to a colour chart (1 = darkest red, 8 = brightest red) by a single observer under bright light conditions. Packed cell volume (PCV) and partial pressure of oxygen (PvO2 ) in the blood were also measured on the syringe blood. Normally distributed data were compared using a two tailed t -test, and non-normally distributed data were compared using a Mann–Whitney U -test. Significance was set at p < 0.05.
Results Camelid venous blood was significantly brighter red than that of horses and ponies both on the white tile ( p = 0.0003) and in the syringe ( p = 0.0001). PCV was significantly lower in camelids (32 ± 4%) compared with horses (37 ± 5%). Partial pressure of oxygen values were similar between groups.
Conclusions and clinical relevance Jugular venous blood in alpacas and llamas is significantly brighter red than that of horses. Colour should not be used as a sole determinant of venous or arterial catheterization in this species. 相似文献
Study design Prospective clinical evaluation.
Animals Twelve South American camelids (eight llamas, four alpacas), eight horses and ponies (control group).
Methods Appropriately sized catheters were placed in the jugular vein of each animal under local anaesthesia. The blood spilt before the catheter was capped was caught on a white tile. A sample of blood was drawn for blood-gas analysis. The brightness of the blood (both on the tile and in the syringe) was matched to a colour chart (1 = darkest red, 8 = brightest red) by a single observer under bright light conditions. Packed cell volume (PCV) and partial pressure of oxygen (PvO
Results Camelid venous blood was significantly brighter red than that of horses and ponies both on the white tile ( p = 0.0003) and in the syringe ( p = 0.0001). PCV was significantly lower in camelids (32 ± 4%) compared with horses (37 ± 5%). Partial pressure of oxygen values were similar between groups.
Conclusions and clinical relevance Jugular venous blood in alpacas and llamas is significantly brighter red than that of horses. Colour should not be used as a sole determinant of venous or arterial catheterization in this species. 相似文献
35.
GT Bleck MB Wheeler LB Hansen H Chester-Jones DJ Miller 《Reproduction in domestic animals》2009,44(2):241-247
It is believed that milk production is determined by the number and activity of mammary secretory cells. Secretory activity, as assessed by milk volume, depends on secretion of the major osmole in milk, lactose, which is produced by lactose synthase. The amount of either of the two proteins in lactose synthase may regulate milk production. The objective of this study was to determine whether the concentrations in milk of the two components of lactose synthase, α‐lactalbumin (α‐LA) and β1,4‐galactosyltransferase (B4GALT), were related to genetic background, stage of lactation, breed or parity of dairy cows. α‐Lactalbumin and B4GALT concentrations were measured by ELISA and by enzyme assays, respectively, from single milk samples. Two herds with a total of 279 cows were used in the analysis. One herd contained Ayrshire, Brown Swiss, Holstein and Jersey cows; the second herd contained two groups of cows; Holsteins selected for high milk production and Holsteins with 1960s genetics. The α‐LA concentration in milk was greater in Jerseys and Ayrshires than in Holsteins and Brown Swiss. However, no difference in α‐LA concentration was observed in milk from high and low genetic merit cows in the Minnesota herd or among different genetic backgrounds in the Illinois herd. β1,4‐Galactosyltransferase concentrations were similar for all groups that were analyzed. α‐Lactalbumin concentrations were positively correlated with milk protein concentration, milk fat concentration and lactose concentration. β1,4‐Galactosyltransferase concentration in milk exhibited a strong positive correlation with number of days in milk. Although the concentration of B4GALT increased as lactation progressed, the values did not show any correlation with persistency of lactation or late lactation milk production. In conclusion, this survey shows that the two components of lactose synthase are each correlated to protein concentration and individually correlated to the concentration of other milk components and stage of lactation. 相似文献
36.
Information on the mating and dispersal behaviour of the rice stem borers Scirpophaga incertulas and Chilo suppressalis is necessary for the design of resistance management strategies for rice varieties genetically engineered with toxin genes from Bacillus thuringiensis (Bt). We investigated whether S. incertulas and C. suppressalis move from the site of adult eclosion before mating to determine the likelihood that random mating will occur between adults eclosing in fields of Bt rice and refuge fields of non-Bt rice. Observations were made under laboratory, screenhouse and field conditions. Almost all S. incertulas males and females flew out of sight after cuticle expansion and hardening, as did most C. suppressalis. Approximately 15% of C. suppressalis females called and mated within 3?m of the site of eclosion, and approximately 5% of C. suppressalis males mated within 5?m of the site of eclosion. These results suggest that random mating is likely to occur between S. incertulas eclosing in Bt rice fields and nearby refuge fields. Although a small proportion of C. suppressalis did not move far before mating, random mating of moths from Bt and nearby refuge fields is also likely to occur in this species if Bt-resistant moths are rare. 相似文献
37.
Introduction and elimination of Bovine Viral Diarrhoea Virus in a commercial beef herd: a case study
MB Allworth R Long AK Smith EL Bergman M Hernandez-Jover 《Australian veterinary journal》2020,98(12):596-601
Routine Bovine Viral Diarrhoea Virus (BVDV) monitoring of a commercial beef herd in southern New South Wales over a 10-year period provided an opportunity to assess the impact of the introduction of BVDV on that herd. BVDV antibody testing provided strong evidence that the herd was initially free of BVDV (2009–2011). Testing from 2012 suggested BVDV had been introduced into the herd and this was confirmed in 2015 with the identification of persistently infected (PI) animals. Having become established in the herd, the owners then set out to eliminate BVDV from the herd. Antigen testing aimed at identifying PI animals revealed BVDV was already absent from the herd. Subsequent antibody testing confirmed that the herd was now free from BVDV. Despite the incursion of BVDV in this herd, there was little measurable impact on reproductive performance (pregnancy rates), although suspected increased calf losses from birth to calf marking were reported. This is the first time such self-clearance has been documented as part of a longitudinal study under Australian conditions. 相似文献
38.
39.
J. Fraser Mc Connell BVM&S Laurent S. Garosi DVM Ruth Dennis Vet MB Ken C. Smith BVM&S PHD 《Veterinary radiology & ultrasound》2003,44(5):537-541
An 8-month-old German Shepherd dog was presented for investigation of pelvic limb gait abnormality. Neurolocalization indicated a T3-L3 spinal cord lesion. The myelographic appearance was of an intramedullary lesion at T9/10, but upon subsequent magnetic resonance imaging it was determined that the mass was extramedullary. A diagnosis of nephroblastoma was made on histological examination. The imaging features of this rare tumor and the differentiation of intradural-extramedullary and intramedullary masses are discussed. 相似文献
40.
Mary B. Mahaffey DVM MS Don L. Barber DVM MS Jeanne A. Barsanti DVM MS Wayne A. Crowell DVM PhD 《Veterinary radiology & ultrasound》1984,25(6):254-259
Double-contrast cystograms and cystometrograms were performed simultaneously in each of six male and six female dogs with normal urinalyses. The dogs were sedated with oxymorphone and acepromazine. Detrusor reflex occurred in 11 of 12 dogs. After bladder infusion of 0.88 ml/kg of positive-contrast medium, there was mucosal irregularity in eight of 12 dogs and bladder shape distortion in 12 of 12 dogs. Bladder distortion decreased with progressive infusion of CO2 , and mucosal irregularity was eliminated after infusion of 50–100 ml CO2 . The bladder neck in all dogs was initially located within the pelvic canal. In ten of 12 dogs, the bladder neck was cranially displaced when the bladder was fully distended. Bladder wall thickness was approximately 1 mm circumferentially at all degrees of distention. There was no discernible difference between bladder shape prior to and at initiation of contraction. It was concluded that radiographic determination of a normal urinary bladder can be made without complete bladder distention and that cystograms and cystometrograms can be routinely performed simultaneously in dogs in which both procedures are required. 相似文献