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Paraffin blocks and mineral oil were used as a model to determine the effect of dependency versus nondependency on radiographic visualization of lung lesions in lateral thoracic radiographs. It was concluded that the increased opacity of the material surrounding the lesion, not contact between the heart and the lesion, was responsible for the inability to detect lung disease in the dependent lung. The results were tested in dogs with pneumonia in the right middle lung lobe. When the dog was in right lateral recumbency, the dependent right lung was increased in opacity and decreased in volume and the pulmonary lesion was difficult to detect. When the dog was in left lateral recumbency, the nondependent right lung was increased in volume and decreased in opacity and the pulmonary disease was clearly visible. A single recumbent lateral radiograph must not be used to assess a dog with suspected lung disease because lesions in the dependent lung lobes may not be detected.  相似文献   
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Four horses were stabled and fed a diet of hay ad libitum, and 2 kg oats per animal per day, for a month. The basic diet was then supplemented with molybdenum, at a rate of 20 mg/kg dry matter for 4.5 months. For one month of this period the diet was supplemented also with sulphur at a rate of 1.2 g/kg dry matter. Analyses of jugular blood samples, obtained at intervals varying between two and 20 days, showed no evidence of a decline in total plasma copper or of an increased proportion of trichloroacetic acid (TCA) insoluble copper in plasma over this period. In separate studies, two other horses were given 99molybdenum (molybdate, 20 to 28 mg Mo, 4 mCi per animal) per os, initially while being fed the basic diet and later while maintained on the molybdenum supplemented diet. 99Molybdenum appeared rapidly in plasma, but the radioactivity was then quickly cleared (half-life 7 to 10 h). The 99molybdenum present was identified as (99Mo)-molybdate. There was no evidence of the persistent, protein-bound (99Mo)thiomolybdates which appear in ruminants. These studies indicate that increased dietary molybdenum is unlikely to interfere with copper metabolism in horses.  相似文献   
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Four methods employed in the diagnosis of experimental porcine trichinellosis (trichinoscopy, digestion method, immunofluorescence and enzyme linked immunosorbent assay (ELISA)) were compared by eleven laboratories in the countries of the European Economic Community and Sweden. The aim of this study was to test the reliability of ELISA during the onset of T. spiralis infection. Material from conventionally raised pigs infected with 1500 or 10000 larvae was compared to uninfected controls at Day 17 and Day 21 post infection.The serological techniques gave higher percentages of positive results than the direct techniques. Specific antobodies could be demonstrated with ELISA at an earlier stage and at higher percentages than with the other methods. ELISA micro-assay was the most sensitive procedure.  相似文献   
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Pharmacokinetics of sulfamethazine in male, female and castrated male swine   总被引:1,自引:0,他引:1  
The concentration of sulfamethazine in plasma and sulfamethazine and its metabolites in urine were compared in male, female and castrated male swine. A surgical technique for placement of catheters in the urinary bladder was used to facilitate the collection of urine in males and castrated males. The elimination rate of sulfamethazine from plasma and the excretion of parent drug and metabolites into urine did not differ significantly among females, males and castrated male swine.  相似文献   
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