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991.
Temporomandibular dysplasia was found in six American Cocker Spaniels related to each other. Clinical signs and diagnosis are described.  相似文献   
992.
The viewpoint presented is that, because compensatory functional adjustment of the residual nephrons occurs in chronic renal disease, reduction in nephron number usually exceeds 70% before a diagnosis is made. The case that earlier diagnoses are likely if laboratory medicine values are measured and interpreted with a maximum of efficiency is then made. The laboratory data more commonly used in practice for the clinical assessment of renal function in the dog are presented and some comparisons with findings in man are made. The information originates from clinical and experimental observations of the authors, as well as from a literature review. The laboratory data presented and discussed includes glomerular filtration rate and the clearance of nitrogenous waste (urea and creatinine), plasma protein concentration, plasma osmolality, renal concentrating capacity, and urinary constituents, particularly its protein concentration and sediment (centrifuge deposit). All parameters recommended for the clinical assessment of chronic renal failure are considered qualitatively, and some are also dealt with quantitatively.  相似文献   
993.
A 3-month-old English Bulldog was found to have a discontinuity between the ascending and descending aorta. There were no signs of illness associated with the interruption. The descending aorta was supplied with blood by collateral circulation. An aortic graft of woven synthetic material was surgically implanted to connect the ascending and descending aorta. Without any restrictions on the dog's activity, the dog has lived for over 1 year and continues to do well.  相似文献   
994.
995.
Quantitative fat and trypsin analysis was done on the feces of dogs with chronic diarrhea. The results of clinical examination, quantitative fecal analysis, and other laboratory tests permitted assignment of the dogs into one of 4 groups: (1)pancreatic exocrine insufficiency,(2)small intestinal malabsorption,(3)colitis, and(4)other nonspecific or incompletely diagnosed diarrhea. The mean 24-hour fat output was significantly higher (p less than 0.01) in dogs with malabsorption or pancreatic insufficiency than in clinically normal dogs, dogs with colitis, or dogs with nonsteatorrheic diarrheas. The mean 24-hour trypsin output with pancreatic insufficiency was significantly (P less than 0.01) lower, and in dogs with malabsorption, significantly (P less than 0.05) higher than in clinically normal dogs. Normalization of the output data for body weight enhanced the value of fat and trypsin analyses in the differentiation of pancreatic insufficiency and intestinal malabsorption from other causes of chronic canine diarrhea.  相似文献   
996.
Seventeen cases of colorectal polyps in the dog were seen at the Ontario Veterinary College over a 12-year period. The mean age of occurrence was 6.9 years, and males and females were almost equally affected. The Collie was the most frequently affected breed (4/17). The clinical signs were typically dyschezia, periodic intermittent diarrhea and melena, and rectal prolapse of the polyp. The histopatholic classifcation were hyperplastic polyp (1), papillary adenoma (1), tubular adenoma (4), papillotubular adenoma (10), and unclassified (1). Severe epithelial atypia, likely carcinoma in situ, was apparent in 5 of the papillotubular adenomas. Retrospective analysis of survival data after polypectomy suggested a good prognosis, but the results were inconclusive and it is possible that some of the polyps represented premalignant lesions. Large polyps (greater than 1 cm in diameter) frequently had marked epithelial atypia and were considered more likely to recur or to become malignant.  相似文献   
997.
Cattle on 18 of 21 farms in north-east Scotland were found to have low whole blood activities of the selenium-containing enzyme, glutathione peroxidase (less than 5 units per ml whole blood), and a low blood concentration of selenium (less than 0.05 mg per litre). These cattle had all been fed on locally produced feedstuffs without any mineral supplementation. The low selenium status in cattle occurred on farms with soils derived from a range of parent material, no one particular type predominating.  相似文献   
998.
Sulfadimethoxine was administered (IV) to suckling pigs (1 to 2 weeks old) and to growing pigs (11 to 12 weeks old) at a dosage of 55 mg/kg of body weight (single dose). Blood samples were collected over a 48-hour period, and the animals euthanatized were used for measurements of plasma and tissue concentrations of the drug. The blood data were described, using a one-compartment pharmacokinetic model. The blood concentration curves for the two groups of pigs had a consistent depletion pattern with greater than therapeutic concentrations (50 micrograms/ml) of the drug persisting through 12 hours after the drug was given. Sulfonamide blood concentrations were 4 and 11 times that of the method sensitivities in the older (growing) and younger (suckling) pigs, respectively, at 48 hours after treatment. In four of the five pharmacokinetic variables studied, a significantly higher (P less than 0.01) degree of efficiency was observed in the ability of the older pigs to eliminate the drug than in the younger pigs.  相似文献   
999.
Faecal egg counts were determined twice weekly for two groups of four-month-old worm free cross Suffolk lambs experimentally infected with 100 and 320 Ostertagia circumcincta larvae, five times per week for 20 weeks. The group mean egg count in both groups rose to a maximum of approximately 500 eggs per gram during weeks 12 to 14 and had fallen to less than half of that value at slaughter. There was no statistical difference in egg output between these two groups or between them and a comparable group of lambs receiving 4000 Ostertagia circumcincta larvae per day. No significant changes in live weight gain or serum pepsinogen levels were observed in the lambs given 100 and 320 larvae per day.  相似文献   
1000.
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