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排序方式: 共有613条查询结果,搜索用时 15 毫秒
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Comparison of penicillin, oxytetracycline, and trimethoprim-sulfadoxine in the treatment of acute undifferentiated bovine respiratory disease 总被引:6,自引:5,他引:1
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Mechor GD Jim GK Janzen ED 《The Canadian veterinary journal. La revue veterinaire canadienne》1988,29(5):438-443
Penicillin, oxytetracycline, and a trimethoprimsulfadoxine combination were compared as first choice antibiotics for the treatment of acute bovine respiratory disease in weaned beef calves. There was no statistical difference in the mortality losses due to respiratory disease; however, the case fatality rate in the trimethoprim-sulfadoxine treatment group (3%) was markedly lower than in the penicillin (10%) and oxytetracycline (8%) treatment groups. The trimethoprim-sulfadoxine group also had statistically fewer treatment days compared to the penicillin and oxytetracycline groups (p < 0.05). Inclusion of mortality costs in the calculation of treatment costs demonstrated that treatment of the trimethoprimsulfadoxine group was appreciably less costly than treatment of the other groups. Temperature response abnormalities, defined as either an elevation in temperature or a failure of temperature to drop from one treatment day to the next, were associated with a relapse rate of approximately 50%. In vitro antibiotic sensitivity testing of Pasteurella haemolytica isolated from pretreatment nasal swabs was not a useful predictor of treatment success of antimicrobials. 相似文献
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Ginder GD 《Science (New York, N.Y.)》1985,228(4701):865-866
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Elderly migration and development in small communities 总被引:1,自引:0,他引:1
"This paper develops a conceptual model of the process of community change [in the United States] in response to elderly inmigration. Analysis of intra-regional variation in elderly migration patterns in Appalachia, and synthesis of an emergent literature on the benefits and costs of attracting elderly migrants, serve as a backdrop for case studies, based on field observations and interviews, of three contrasting Appalachian communities at different stages of development as retirement destinations." 相似文献
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Geology of the athabasca oil sands 总被引:1,自引:0,他引:1
Mossop GD 《Science (New York, N.Y.)》1980,207(4427):145-152
In-place bitumen resources in the Alberta oil sands are estimated at 1350 billion barrels. Open-pit mining and hot water extraction methods, which involve the handling of huge tonnages of earth materials, are being employed in the two commercial plants now operating. In situ recovery methods will be required to tap the 90 percent of reserves that are too deeply buried to be surface mined. Development of in situ technologies will be painstaking and expensive, and success will hinge on their compatibility with extremely complex geological conditions in the subsurface. 相似文献
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A 4-year-old Arab mare was diagnosed with disseminated cryptococcosis, including osteomyelitis of the proximal phalanx of the left hind limb, osteomyelitis with associated soft tissue granuloma of a rib and disseminated, large cryptococcal nodules in the lungs. The lesion in the dorsoproximal aspect of the proximal phalanx had a large area of cortical lysis with spiculated periosteal new bone and extensive soft tissue swelling. The affected rib had a pathological fracture. Cryptococcal osteomyelitis has not been previously reported in horses but should be considered as a differential diagnosis, particularly in endemic regions. 相似文献
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Rosen GD 《British poultry science》2007,48(1):27-32
1. This holo-analysis of the effects in turkey nutrition of Bio-Mos(R) (BM) (Alltech Inc., Nicholasville, KY) aims to elaborate comprehensive empirical models for the assessment of responses under practical conditions and for its comparison with other potential pronutrient antibiotic replacements. 2. The data bank utilised was obtained from 54 publications on BM in turkeys from a total collection of 57 papers (1995-2003) on the use of saccharide products as turkey feed additives. These yielded 33 start-to-finish negatively-controlled feed intake, liveweight gain and feed conversion and 24 mortality effects in the USA, France and Poland, using 12,723 birds with a mean of 212 birds per treatment. 3. The feed, gain, conversion and mortality responses to BM compared with the relevant negative controls average -243 g, 57.0 g, -0.0156 and 1.29% with coefficients of variation of 451, 451, 705 and 426%, respectively. Beneficial gain, conversion and mortality effects were found in 52, 52 (33% jointly) and 52% of the tests, respectively. 4. Holo-analytical multiple regression models comparing conventional Por=0.10 out and less stringent Por=0.34 out partial regression coefficient standards, with and without>or=1.5xroot mean square error outliers, contain significant independent variables for negative control performance, duration, year of test, not-USA test, discontinuous dosage, cage housing, mash feed, feed antibiotic, feed anticoccidial, disease condition and high control (>10%) mortality. 5. These developmental models indicate fruitful pathways for future developments with an accent on the definition of specific dose-response relationships, whilst also confirming the value and future potential for BM in turkey production in praxis. 相似文献