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991.
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994.
Absorption of endotoxin from the gastrointestinal tract was evaluated in hay-fed and lactic acidotic sheep duodenally infused with 10 mg of Escherichia coli endotoxin, and in lactic acidotic sheep not infused. The effect of abomasal fluid on biological activity of endotoxin was also evaluated. Leukopenia was the criterion used for detecting endotoxemia. Absorption of endotoxin from the gastrointestinal tract was not detected in either hay-fed or lactic acidotic sheep. Endotoxin appeared to maintain its activity after incubation with abomasal fluid, and the presence of endogenous endotoxin in abomasal contents was indicated. The results indicate that endotoxin of alimentary origin may not be involved in the lactic acidosis syndrome in ruminants.  相似文献   
995.
Intranuclear cisternal and vesicular structures, bound by a single membrane, were observed for the first time in some glandular "bird's eye" cells of canine circummanal gland carcinomas. The role of these intranuclear structures is not clear. It is suggested that they may be involved in cellular adaptation to an environment of nutrient deficiency, as a result of cell overcrowding.  相似文献   
996.
997.
Excessive mortalities were experienced in the bigger rainbow trout (Salmo gairdneri) at an efficiently managed trout farm. All tests for known toxins in the feed and water proved to be negative. A faecal Streptococcus which belongs to the Lancefield group D but which could not be identified as belonging to any of the recognized species within this group, was isolated from the spleens, livers and kidneys of affected fish. Pathogenicity studies with this organism proved it to be highly fatal to trout but not to Mozambique bream (Sarotherodon mossambicus), banded bream (Tilapia sparrmenii), carp (Cyprinus carpio) or largemouth bass (Micropterus salmoides). The isolation and biochemical characteristics of the organism are described. The symptoms, gross- and histopathology of this disease are described and discussed. The disease resembles a haemorrhagic septicaemia and appears to be associated with intensification and conditions of stress.  相似文献   
998.
999.
Atopy.     
Atopy should be considered an immunological disorder that may result in several clinical conditions including respiratory disease, allergic dermatitis, food allergy dermatitis, and perhaps flea allergy dermatitis. The clinical course of the disease tends to fluctuate from season to season, which makes objective evaluation of injection therapy difficult. The disease is subject to both familial and environmental influences, and dogs maintain the atopic state throughout their life. The disease cannot be cured; however, a combination of symptomatic and specific injection therapy usually provides adequate control of the clinical signs. Owners of atopic dogs should appreciate that their pet has inherently itching skin, a cure for which is unlikely to be found.  相似文献   
1000.
The stratum corneum measured on fresh frozen sections was found to be considerably thicker than previously reported. It was uniformly permeated with sebum, which also formed an intact film over the skin surface and it could readily be divided into two zones. The living epidermis was approximately half as thick as the stratum corneum.  相似文献   
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