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921.
A bovine adenovirus with agglutinating activity was isolated from feedlot calves and classified as serotype 3. The agglutinating activity was shown to be the property of an adenovirus-associated virus (AAV). The AAV was isolated from the bovine adenovirus by isopycnic centrifugation in CsCl; the AAV had a density of 1.4 g/cm2. This AAV is serologically related to bovine AAV-TR-15, but is distinct from bovine parvovirus-1 and primate AAV types 1 to 4, using counterimmunoelectrophoresis and hemagglutination-inhibition.  相似文献   
922.
Bovine adenovirus type 7 was isolated from a 10-month-old calf with fibrinopurulent pneumonia and from 2 newborn calves with pneumoenteritis. The viruses were isolated on calf lung and adrenal gland cell cultures and were identified as serotype 7 by immunoelectron microscopy and serum-neutralization tests.  相似文献   
923.
Aprotinin, a proteinase inhibitor, was evaluated as a pharmacologic aid in dogs subjected to lethal hemorrhagic shock. Survival time, hemodynamic changes, and plasma enzyme analysis were measured as criteria for drug effects. Mixed-breed dogs (n = 14) were divided into 2 groups of 7 each: nontreated dogs in shock (group 1) and aprotinin-treated dogs in shock (group 2). One of 7 dogs in group 1 and 2 of 7 dogs in group 2 survived. Survival time, for the remaining dogs in group 1 (190 min, n = 6) and group 2 (188 min, n = 5) were not significantly different. There was no significant difference in mean arterial pressure, mean pulmonary arterial pressure, cardiac output, or left ventricle systolic pressure associated with aprotinin treatment at any time after hemorrhagic shock. There was no significant difference in plasma lactic acid, aspartate aminotransferase, alanine aminotransferase, creatine phosphokinase, alpha-amylase, and beta-glucuronidase associated with treatment at any time; however, there were significant (P less than 0.05) increases with time. The gastrointestinal tract was the site of most obvious lesions found at necropsy. Lesions varied considerably in extent and severity without apparent correlation to the treatment regimen. These experiments did not show beneficial effects of aprotinin in dogs subjected to hemorrhagic shock, but neither did they completely rule out some valuable actions that may have been obscured by the type of model used.  相似文献   
924.
1. Blackening of the skin in factory processed cooked hens has been associated with elevated copper levels.

2. The degree of blackening was not directly related to copper content although the latter level was always higher than in control hens.

3. Simulated factory procedures, using scald water at 53 °C or 60 °C containing 50 mg Cu2+/1 and 50 mg C12/1, produced blackened skins of varying intensity on cooking.

4. It is suggested that the problem arose from a malfunction of the chlorination plant which produced excessive levels of chlorine and low pH, followed by erosion of copper from water pipes and subsequent interaction of copper and chlorine with the chicken skin.  相似文献   

925.
1. n‐Paraffin‐grown yeast and a mixture of soyabean meal and fish meal were compared in the net protein utilisation (NPU) test, and as protein supplements in diets for broilers up to 4 weeks of age.

2. The difference between the NPU values, 0.66 for yeast and 0.80 for the soyabean meal and fish meal mixture, could largely be attributed to the high nucleic acid content of the yeast.

3. Chicks given the diet containing yeast (190 g/kg) did not grow as rapidly as those given the soyabean meal and fish meal reference diet, and the reduced growth could only partly be explained by a marginal deficiency of methionine.

4. Food conversion efficiency with the yeast diet was improved by maize oil while responses to α‐tocopheryl acetate and sodium selenite were inconsistent.

5. Chicks grew well when yeast replaced fish meal in the mixture of soyabean meal and fish meal, and when fish meal (194 g/kg diet) was the sole protein supplement.  相似文献   

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"Sound and careful surgery is the sine qua non of wound management; antimicrobials are adjunctive." The key to successful use of prophylactic antibiotics in surgery is careful selection of cases and medication. There are no final rule or formulas that will always give optimal results. Listed below are some guidelines that may assis the clinician in determining the need and form of antimicrobial use. 1. The operation must carry a significant risk of bacterial contamination. Refined-clean and clean procedures should not be given prophylactic antibiotics. 2. Bacterial cultures should be taken when possible, and the medication used for prophylaxis should be effective against the organisms expected to be encountered. 3. Narrow spectrum antibiotics should be used to conserve the body's normal flora. Broad spectrum antibiotics needed to combat resistant infections should not be used for prophylaxis. 4. The antibiotic should be present in the wound in effective concentrations at the time of the incision and be maintained only as long as the risk of new bacterial contamination exists.  相似文献   
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