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1.
Five hypernatremic, diarrheic, neonatal calves were treated mainly by the intravenous administration of 5% dextrose alone or with isotonic sodium bicarbonate. All calves recovered without complications. The average reduction rate of serum sodium concentration was about 4 times that recommended and has not been tried successfully before in hypernatremic scouring calves.  相似文献   
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Background  

The establishment of mutant populations together with the strategies for targeted mutation detection has been applied successfully to a large number of organisms including many species in the plant kingdom. Considerable efforts have been invested into research on tomato as a model for berry-fruit plants. With the progress of the tomato sequencing project, reverse genetics becomes an obvious and achievable goal.  相似文献   
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Ultrasonography is a safe, noninvasive, sensitive, and specific tool for evaluation of the heart and pericardium in patients with cardiac neoplasia. In small animals, the incidence of cardiac neoplasia is low. In dogs, hemangiosarcoma and chemocdectoma are the two most common types of cardiac neoplasia. In cats, lymphosarcoma is the most common form of cardiac neoplasia. Pericardial effusion is a common and potentially life-threatening consequence of cardiac neoplasia. Pericardial effusion leads to a rise in the intrapericardial pressure, resulting in varying degrees of hemodynamic compromise. Cardiac tamponade occurs when the intrapericardial pressure equals or exceeds right ventricular diastolic filling pressures, leading to a decreased cardiac output. Pericardiocentesis is used to stabilize animals with life-threatening cardiac tamponade, and to obtain fluid samples for diagnostic evaluation. The fluid should be quantified and characterized. If the etiology of the effusion is not known, then a sample of the fluid should be submitted for fluid analysis and cytology. Serious complications associated with pericardiocentesis are rare. Complications include cardiac puncture, arrhythmias, and laceration of the tumor or coronary artery, resulting in intrapericardial hemorrhage.  相似文献   
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Conventional tillage winter wheat (Triticum aestivum) (WW)–summer fallow reduces soil productivity and increases soil erosion. Conservation tillage management, together with intensive cropping may have the potential to reverse these sustainability concerns. The objective of this study was to determine the effects of conventional tillage (CT) and no-tillage (NT) systems on grain yield of long-term annual cropping of monoculture WW, spring wheat (SW), and spring barley (Hordeum vulgare) (SB) grown with or without fertilizer, in the Pacific Northwest region of the USA. In unfertilized crops, grain yield of WW, SW, and SB was 15%, 25%, and 50% higher, respectively, in CT than in NT plots, an indication of the involvement of yield limiting factors under the NT cropping system. When fertilized, there were no significant differences in grain yield of WW. Yields of SW and SB, however, remained 21% and 15% higher, respectively, in CT than in NT, an indication that factors other than fertility were involved. These results suggest that in order for NT management to be widely adopted by area growers, the yield-limiting factors need to be addressed.  相似文献   
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The effects of feeding different levels of milk to diarrheic calves (n = 19) supplemented with oral electrolytes were investigated. In the early stages of the disease the calves were fed either enough milk to maintain normal growth in a healthy calf, one half that volume or no milk. The three groups were further subdivided according to whether or not the electrolyte solution contained bicarbonate. A full milk ration allowed uninterrupted weight gains of 1% body weight/day (p = 0.003), but caused greater inappetence (p = 0.003 to 0.037) at the beginning of the trial than lower levels of milk intake. Electrolyte solutions with bicarbonate reduced growth rates in milk fed calves (p = 0.014). The density of fat stores increased with the level of milk feeding (p = 0.04 to 0.053). The mitotic index of the duodenal mucosa increased with milk feeding (p = 0.08), indicating a superior mucosal regeneration potential. Thymic atrophy was pronounced in those calves fed no milk (p = 0.001). It was concluded that the continued feeding of milk to diarrheic calves was beneficial. Electrolyte solutions containing bicarbonate should be avoided when milk is fed to diarrheic calves.  相似文献   
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Sulbactam-ampicillin is a combination of sulbactam, a beta-lactamase inhibitor, and ampicillin, a broad spectrum beta-lactam antibiotic. The efficacy of sulbactam-ampicillin was evaluated in the treatment of neonatal calf diarrhoea under conditions where a major proportion of the calves were excreting enterobacteria which were resistant to beta-lactam antibiotics. In a series of six studies with a common experimental design, three treatments (sulbactam-ampicillin, ampicillin alone and untreated control) were compared in over 300 Friesian and Ayrshire calves aged between three and 10 days and of known immunological status as determined by their zinc sulphate turbidity values. A mortality rate of 26.4 per cent in the negative control calves was reduced to 14.0 per cent with ampicillin alone and 9.5 per cent with sulbactam-ampicillin. The probability of diarrhoea subsequent to initiation of treatment was reduced from 0.50 in the negative control calves to 0.44 with ampicillin alone and 0.35 with sulbactam-ampicillin. The differences in mortality and diarrhoea observed between the calves treated with sulbactam-ampicillin and the calves in each of the other treatment groups were statistically significant. The superior efficacy of sulbactam-ampicillin is explained by the inhibitory effect of sulbactam on the beta-lactamases produced by resistant bacteria, thus rendering them susceptible to the ampicillin in the combination.  相似文献   
10.
Transvenous cardiac pacing is a commonly employed treatment for symptomatic bradyarrhythmias in dogs. Medical management of these conditions has not proven to be successful leaving pacing as the only viable alternative. The technique of pacemaker implantation is not difficult, but successful pacemaker therapy requires an understanding of electrophysiology, cardiac fluoroscopic anatomy, pacemaker instrumentation, and programming. Proper patient selection and identification of the underlying rhythm disturbance is essential to a successful clinical outcome. This article discusses the indications, equipment, techniques, complications, and outcome of permanent transvenous cardiac pacing.  相似文献   
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