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71.
Three Portuguese water dog siblings, all females aged 5 to 7 months, were killed following a brief period of neurologic disease. Tissues were processed for light and electron microscopy and for biochemical analyses. All pups had membranous cytoplasmic inclusions in neurons throughout the brain and spinal cord. Cytoplasmic vacuoles were present in cells of many organs outside the nervous system. GM1 ganglioside in brain was markedly elevated in all three dogs, and beta-galactosidase activity was less than 10% of control values. These findings are similar to those in GM1 gangliosidosis of man and animals although the number of organs and tissues containing vacuolated cells is greater.  相似文献   
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The brainstem auditory evoked response (BAER) was recorded from 7 unanesthetized and 27 methoxyflurane anesthetized dogs. A 0.1 msec, 70 dB stimulus delivered at 10 Hz evoked the expected seven wave BAER. Mean peak wave latencies and standard deviations were calculated. Differences were not found between neither right and left ears, nor male and female dogs. The anesthetized dogs had a significantly longer latency for all waves, except wave I, than the unanesthetized dogs. Use of the BAER as a diagnostic technique for brainstem lesions is recommended.  相似文献   
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A general method for saturation mutagenesis of cloned DNA fragments   总被引:53,自引:0,他引:53  
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In order to study the pathomorphology and immunohistochemistry of peste des petits ruminants, four goats and two sheep were inoculated intranasally with the Malig-Yemen strain of peste des petits ruminants virus. The animals developed fever, nasal discharge, oral erosions, cough and diarrhea. One goat and one sheep died and one moribund goat was killed. Three animals survived the infection. At necropsy, erosive stomatitis, pneumonia and gastroenteritis were found. Histopathologically the pneumonocytes and epithelial cells of the ileum had eosinophilic cytoplasmic and nuclear inclusions. By an indirect immunoperoxidase method, the nuclei and cytoplasm of the ileal epithelial cells of one goat contained positively (brown) stained antigen, which corresponded to viral nucleocapsids by electron microscopy. Virus appeared to be released through the microvilli of the epithelial cells. We also confirmed the formation of giant cells due to peste des petits ruminants virus.  相似文献   
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Sheep pox: experimental studies with a west african isolate   总被引:2,自引:0,他引:2       下载免费PDF全文
Under conditions of a maximum security laboratory, four cross-bred sheep were inoculated intradermally only or intradermally and intratracheally with a West African isolate of sheep pox virus. All sheep had increased temperature and depression by the fourth or fifth day after infection. Nasal and lacrimal discharge and coughing occurred in all sheep but were more severe in sheep receiving the virus via the tracheal route. From the fifth day after infection, numerous papular erythematous skin lesions developed at the inoculation sites. These were 3-7 mm in diameter and gradually became nodular. Some of these lesions healed and others coalesced to form tumorlike masses. In one sheep, euthanized 14 days after intradermal and intratracheal inoculation, nodular lesions were found in the skin around the eyes, nostrils, oral and perianal regions, the mucosa of the rumen and throughout the lungs. Histologically, skin nodules were characterized by ischemic necrosis, vasculitis, microvesicualtion, eosinophilic cytoplasmic inclusions in the dermal epithelial cells and vacuolar nuclear degeneration. The pulmonary lesion was that of proliferative alveolitis with occasional cytoplasmic inclusions in the alveolar cells and macrophages. Ultrastructurally, large cuboidal virus particles were found both in the skin lesion and inoculated tissue cultures. The sheep pox virus structure was easily distinguished from contagious ecthyma virus, a parapoxvirus which causes sporadic disease in Canada. Serum neutralizing antibodies developed in all the sheep by 14 days postinfection.

The clinical and pathological characteristics of experimental sheep pox produced with this West African isolate were similar to those caused by Neethling virus of lumpy skin disease in cattle.

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