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161.
Four bovine meningeal tumors from a total of 14 brain tumors were recorded in the files of the Ontario Veterinary College and the Ontario Veterinary Laboratory Services Branch from the years 1966 to 1984. The affected cattle ranged in age from 10 months to adult. They exhibited various nervous signs and, in each case, the animals became recumbent. Tumors were located in various areas of the central nervous system. Neoplastic cells had oval vesicular nuclei containing numerous cytoplasmic invaginations. Virus particles were not observed. A fibroblastic appearance, with the presence of loose whorls or bundles, was present in all. Three of the tumors were invasive and were classified as a fibroblastic meningioma.  相似文献   
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In dogs with spontaneous heart disease, an electronically generated measurement of cardiac vagal tone, the cardiac index of parasympathetic activity, was a sensitive, simple and inexpensive measure of the severity of heart failure. Dogs with cardiac disease and an index score less than 3 were at 15.8 (95 per cent confidence interval 2.9 to 87.2) times the risk of dying within a year than those with a score of 3 and over. The measurement of the index provided an objective and reliable beat-by-beat measurement of cardiac vagal tone, which was prognostically useful in dogs with heart disease.  相似文献   
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The comparative pathogenicity of two porcine haemophilus species   总被引:3,自引:0,他引:3  
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Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are among the most common infectious diseases of cats. Although vaccines are available for both viruses, identification and segregation of infected cats form the cornerstone for preventing new infections. Guidelines in this report have been developed for diagnosis, prevention, treatment, and management of FeLV and FIV infections. All cats should be tested for FeLV and FIV infections at appropriate intervals based on individual risk assessments. This includes testing at the time of acquisition, following exposure to an infected cat or a cat of unknown infection status, prior to vaccination against FeLV or FIV, prior to entering group housing, and when cats become sick. No test is 100% accurate at all times under all conditions; results should be interpreted along with the patient's health and risk factors. Retroviral tests can diagnose only infection, not clinical disease, and cats infected with FeLV or FIV may live for many years. A decision for euthanasia should never be based solely on whether or not the cat is infected. Vaccination against FeLV is highly recommended in kittens. In adult cats, antiretroviral vaccines are considered non-core and should be administered only if a risk assessment indicates they are appropriate. Few large controlled studies have been performed using antiviral or immunomodulating drugs for the treatment of naturally infected cats. More research is needed to identify best practices to improve long-term outcomes following retroviral infections in cats.  相似文献   
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