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31.
The purpose of this study was to determine if the presence of histopathologically tumor-free versus nontumor-free margins was prognostic for relapse or tumor-related death in dogs following surgical excision of single or multiple cutaneous mast cell tumors confined to the skin without evidence of metastasis to lymph nodes or other noncutaneous sites. Differences in tumor-related death or frequency of relapse between the two groups were not significant. Failure to achieve histopathological tumor-free margins frequently did not lead to local relapse. All tumor-related deaths occurred following local relapse. The lack of statistical support for an association between prognosis and histopathological tumor-free versus nontumor-free margins may be a result of small sample size.  相似文献   
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Syringohydromyelia secondary to foramen magnum overcrowding is described in seven Cavalier King Charles spaniels. Clinical signs were consistent with a central spinal cord lesion. The most common signs were persistent scratching at the shoulder region with apparent neck, thoracic limb, or ear pain and thoracic limb lower motor neuron deficits. The diagnosis was made by magnetic resonance imaging. The syringohydromyelia is postulated to be a consequence of an occipital bone malformation resulting in a small caudal fossa and cerebellar herniation. Clinical signs improved but did not completely resolve when the dogs received treatment with corticosteroids or nonsteroidal anti-inflammatory drugs.  相似文献   
34.
Nutritional antioxidants have experienced a surge in research and interest in the past 20 years. this surge may be attributed to the improved methodology for investigation as well as the focus on diseases and aging processes related to oxidative stress that lend themselves to opportunistic outcomes. As such, the field of veterinary nutritional antioxidant research is also beginning to yield some interesting results, albeit, small in number compared with laboratory animals and human beings. Nonetheless, this article updates the practitioner on recent advances in research involving nutritional antioxidant applications in companion animals.  相似文献   
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This article is designed to aid the practitioner by maximizing the effectiveness of field postmortem diagnostic investigations. Contents include an outline of the procedure for field necropsy of ruminants, recommended tools and supplies, and guidelines for sample collection and submission.  相似文献   
36.
Objective: To report the manifestations, history, and pathophysiologic basis of disease in 2 dogs with Amanita muscaria toxicosis. Case summaries: Two dogs were evaluated for an acute onset of gastroenteritis and seizures. A. muscaria toxicosis was suspected in each dog after confirmation of environmental exposure and visualization of ingested mushrooms in vomitus. The diagnosis was confirmed following identification of toxic Amanita metabolites in the urine and serum of each dog. Administration of supportive and symptomatic therapies resulted in the complete recovery of each animal. Unique information provided: Ingestion of the mushroom, A. muscaria, by dogs can result in acute gastrointestinal distress that precedes a potentially life‐threatening central neurologic syndrome characterized by seizures, tremors, and somnolence. Central nervous system dysfunction results primarily from the actions of ibotenic acid and its decarboxylation product, muscimol, which are analogues of the neurotransmitters glutamate and γ‐aminobutyric acid (GABA), respectively. Identification of these toxins in the urine and serum of affected dogs using high‐performance liquid chromatography (HPLC) provides a definitive diagnosis.  相似文献   
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Fourteen dogs with histologically-confirmed transitional cell carcinoma (TCC) of the urinary bladder were treated with 300 mg/m2 carboplatin every 3 weeks. Response to therapy was assessed with abdominal radiography, double contrast cystography, urinary bladder ultrasonography and thoracic radiography before therapy and at 6–week intervals during therapy. Dogs were monitored for hematologic toxicity with a CBC and platelet count performed immediately before and 10 to 14 days after carboplatin treatment. Tumor responses included progressive disease in 11 dogs and stable disease in 1 dog. Two dogs were euthanized due to carboplatin toxicity before assessment of tumor response. Toxicity included thrombocytopenia with or without neutropenia in 7 dogs and gastrointestinal toxicity in 6 dogs. Carboplatin therapy was not beneficial in the treatment of TCC in the 14 dogs in this study.  相似文献   
39.
In a growth chamber experiment, 70-day-old seedlings of 10 conifer species were inoculated with Colletotrichum gloeosporioides conidia to determine the host range of the fungus. Based on the percentage of seedlings affected and the disease severity on individual seedlings, the order of most to least susceptibility was: western hemlock (WH), mountain hemlock, western larch, Sitka spruce, Engelmann spruce, Douglas-fir (coastal form, then interior form), white spruce and ponderosa pine; lodgepole pine and western red cedar remained unaffected. Inoculation of WH needles showed that within 24 h C. gloeosporioides conidia germinate and appressoria (penetration structures) form. A growth chamber study demonstrated that the pathogen can infect WH at needle wetness periods as short as 15 min; number of needles affected was higher at 0.5 h, but did not increase further even when wetness was extended up to 8 h. The results are discussed in relation to blight management of greenhouse-grown conifer seedlings.Portion of a Bachelor of Science (Honors) thesis, Department of Biology, University of Victoria, Victoria, British Columbia.  相似文献   
40.
Many Mexican women are deficient in folic acid. Fortification of the corn tortilla could be an effective way to help increase the folic acid levels among the Mexican population. Previous studies have shown significant folic acid losses in the masa dough as it is held before baking. This loss in folic acid could be owing to utilization by lactic acid bacteria naturally present in the masa. The objective of this study was to determine the effect of bacteria native to corn masa on the folic acid content in masa. Bacteria in dough samples from six mills in Guadalajara, Mexico, were isolated and identified. Bacterial isolates were inoculated into sterile fortified corn masa flour, which was converted to masa and held at 56°C for 0, 3, and 6 h, replicating the conditions of freshly milled masa as held before baking. All samples, including the control, showed losses of folic acid between 66 and 79% w/w in the first 3 h of incubation. Because folic acid degradation in the sterile control sample was not different than the inoculated sample results, the decline in folic acid was not owing to bacteria (mainly Streptococcus spp.) present in the masa flour but appeared to be a chemical degradation related to time and temperature.  相似文献   
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