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1.
Nine combinations of dosages and concentrations of D-xylose were given orally to eight clinically normal, immature dogs. The concentrations and dosages of D-xylose consisted of 5%, 10%, and 20% at 250 mg/kg, 500 mg/kg, and 750 mg/kg. Serum samples were collected at 0, 30, 60, 90, 120, and 180 minutes. Serum xylose was quantitated using the phloroglucinol microassay technique. A peak in serum xylose concentration was seen for each treatment combination at 60 or 90 minutes after dosing. The dosage effect was important in influencing serum xylose values (P < 0.0001). As the test solution dosages increased from 250 mg/kg to 500 mg/kg and 750 mg/kg, serum xylose values (when dosage was analyzed over the length of the entire test) rose linearly (R(2) = 0.98). The treatment combinations of 5% and 20% xylose solutions dosed at 750 mg/kg produced the highest serum xylose values at the 60- and 90-minute peak intervals. The independent effect of concentration was significant (p < 0.001) but was overridden by the stronger dosage effect. Serum xylose concentrations varied little statistically (p > 0.05) when the 5%, 10%, and 20% solutions were compared at a specific dosage.  相似文献   
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Endoscopic balloon dilation of benign esophageal strictures was performed in 18 dogs and 10 cats with a median age of 4 years. Stricture formation was associated with a recent anesthetic episode in 18 patients. Regurgitation was the most common clinical sign and was present a median of 4 weeks before dilation. Most animals had a single stricture; median diameter was 5 mm, and median length was 1 cm. Esophagitis and mucosal fibrosis were detected in 9 patients each. Dilation was performed with progressively increasing diameter balloons, from 6 to 20 mm. After dilation, mucosal hemorrhage was mild to moderate in most patients. Esophageal perforation was the only serious complication and occurred in 1 patient. Postdilation therapy consisted of administration of cimetidine, metoclopramide, sucralfate, and prednisone in most animals. The median number of dilation procedures performed in each animal was 2, with a range of 1-5. The median interval between dilations was 13 days. Stricture diameter markedly increased with subsequent dilations. Median duration of follow-up was 131 weeks. A successful outcome occurred in 88% of patients, with most animals able to eat canned, mashed, or dry food without regurgitation. Mucosal fibrosis was associated with a better clinical response score, while increasing age was weakly associated with fewer dilations. The dilation protocol used in this group of animals was safe and efficacious.  相似文献   
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Ohne ZusammenfassungAnschrift d. Verf.: BML, Bonn.  相似文献   
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Staphylococcus intermedius (S. intermedius) was isolated from 88.6% and 49.4% of skin and ear samples, respectively, during the years 1992 through 1997, and frequency of isolation remained unchanged. More than 95% of all S. intermedius isolates were susceptible to cephalothin and oxacillin, providing support for empirical treatment of canine skin and ear infections with cephalexin. Pseudomonas aeruginosa (P. aeruginosa) was isolated from 7.5% and 27.8% of skin and ear samples, respectively. The frequency of isolation from skin samples increased over the study period. Because of multidrug-resistant profiles for P. aeruginosa isolates, especially for ear isolates, empirical treatment of P. aeruginosa infections is not advisable.  相似文献   
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Listeria monocytogenes (LM) is a Gram-positive facultative intracellular bacterium that causes fatal meningoencephalitis in humans and ruminants. A current paradigm predicts that intracellular bacteria are controlled by nitric oxide (NO) whose synthesis is catalyzed by inducible nitric oxide synthase (iNOS). The ability of macrophages (Mphi) to express iNOS shows extreme interspecies variability. Here the expression of iNOS and synthesis of NO was studied in listeric encephalitis of cattle, sheep, and goats. iNOS was expressed by a subset of Mphi in cerebral microabscesses in all three species. The level of iNOS expression and the density of cells per lesion expressing iNOS was highest in cattle, intermediate in sheep, and lowest in goats. The accumulation of nitrotyrosine (NT), an indicator of local NO synthesis, was observed in lesions of cattle but not in those of small ruminants. The density of iNOS-expressing cells in lesions was inversely correlated with the number of bacteria. No species differences were observed in regard to reactive oxygen intermediate (ROI) production by stimulated granulocytes, using the flow cytometric dihydrorhodamine-123 (DHR) method indicating ROI generation. Thus, the marked species differences in iNOS expression, NT accumulation, and LM content in lesions of ruminants with listeric encephalitis are explained by different amounts of ROI produced. It suggests that variations in the ability of Mphi to synthesize NO are of pathophysiological significance in listeriosis.  相似文献   
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A serial test meal technique was used in the dog to evaluate the gastric emptying of a liquid test meal. On separate days, a phenol red test meal was placed in the stomach and completely aspirated at different times. A composite representation of the gastric emptying pattern was obtained for each dog, and a set of normative data was generated. Three emptying determinants (emptying time, half-life, and starting index) were calculated. The basic pattern of canine gastric emptying was linear and declined exponentially or as a function of the square root of the gastric volume. A modified emptying-time technique (METT) correlated well with the serial test meal and a set of normative values was determined. The METT was performed by aspirating test meal from the stomach 30 minutes after instillation. The METT was a simple and inexpensive technique that could be performed in 1 short testing period. With the METT, the half-life of gastric emptying was calculated, using the log of the percentage of retention of test meal; gastric emptying time was calculated, using the square root of the percentage of retention of test meal. Acetylpromazine was shown not to alter gastric emptying of a liquid test meal.  相似文献   
8.
Rundschau     
Ohne ZusammenfassungPflanzenschutzorganisation für Europa und die Mittelmeerländer.  相似文献   
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Rundschau     
Ohne ZusammenfassungPflanzenschutzorganisation für Europa und die Mittelmeerländer  相似文献   
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