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101.
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Visceral leishmaniasis was diagnosed in a dog that had been living with his owners in Spain for two years. Clinical diagnosis was somewhat delayed as the disease is largely unknown to Canada and was manifested by a nonresponsive anemia which was not easily explained on peripheral blood evaluation alone, and concomitant interstitial nephritis. On post mortem examination splenomegaly was the main gross pathological finding. Light microscopic examination of bone marrow aspirates and subsequent electron microscopic examination of splenic and hepatic tissues revealed numerous Leishman-Donovan bodies in cells of the reticuloendothelial system. Parasitized reticuloendothelial cells were seen singly or forming granulomata. These latter did not contain giant cells and were confined mainly to the liver and spleen, being sparse and single in the first but extremely numerous and coalescing in the latter. Accumulation of intrafollicular hyaline material was seen in a small number of splenic follicles. Leishman-Donovan bodies on electron microscopic examination had a trilaminar periplast, a large round nucleus with heavy blocks of marginated chromatin and two nucleoli, a short flagellum and a kinetoplast. Lymph nodes and bone marrow had numerous parasitized macrophages but no granulomata. Leishman-Donovan bodies were not detected in the lungs and kidneys both of which exhibited a chronic intersitital reaction. The comparative hematological profile as well as the importance of bone marrow and electron microscopic examinations of the spleen and liver in diagnosis are discussed. The potential public health hazard of leishmaniasis to North America and particularly to Canada is considered.  相似文献   
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Doxorubicin/cyclophosphamide were evaluated as maintenance drugs for dogs with multicentric lymphosarcoma (n = 28). Median remission time of all dogs was 173 days. Remission duration was shorter, however, in dogs with stage IV/V disease, in dogs with pretreatment hypoalbuminemia, and in dogs that had received glucocorticoids before initiation of chemotherapy (P less than 0.04). Nineteen dogs were evaluable for toxicity. Dose-limiting gastrointestinal toxicosis was observed in three dogs, neutropenia was observed in three dogs, and cardiomyopathy was observed in three dogs. The doxorubicin/cyclophosphamide protocol described in this report is safe and effective in treating canine multicentric lymphosarcoma. Clinical stage, pretreatment steroid therapy, and hypoalbuminemia are prognostic factors for response to this protocol.  相似文献   
105.
During 1981, an experiment was conducted to examine the spatial variability of surface temperature within differentially irrigated grain sorghum fields. The measurements were performed at the University of California-Davis in 85 m long transects measured with an infrared thermometer reading at 1.0 m intervals. These measurements were made repeatedly throughout the season. When the data were analyzed to evaluate the spatial variability along each transect, it was found that along the transects the readings at 1 m intervals were not correlated. This lack of structure or spatial dependence within a given field suggests that a random sampling in a field would be adequate for infrared thermometer measurements. During a drying cycle from one irrigation to the next, the variance of surface temperature along a transect increased. However, there was not a statistically significant relationship between the amount of water extracted from the upper 150 cm of the profile when more than 40% of the available water remained. When more than 60% of the available water had been removed, the variance increased above 0.5°C2 but below this amount the variances did not exhibit any significant pattern. These data suggest that the variance of surface temperature within a field may not be a sensitive indicator of the soil water status. Utilizing the fact that the surface temperatures along the transects were random and normally distributed, we calculated that the number of samples needed to achieve a confidence limit of 1.0°C about the mean was 10 samples for a field with more than 40% available soil water and increased to 20 samples as the field dried below the 60% extraction level. These data suggest that the spatial variability techniques could be utilized to evaluate agricultural fields for their distribution efficiencies and problems. In application the samples required per field are a manageable number and could be analyzed with classical statistical methods.  相似文献   
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BACKGROUND: The Systematized Nomenclature of Medicine (SNOMED) is an established standard nomenclature for the expression of human and veterinary medical concepts. Nomenclature standards ease sharing of medical information, create common points of understanding, and improve data aggregation and analysis. OBJECTIVES: The objective of this study was to determine whether SNOMED adequately represented concepts relevant to veterinary clinical pathology. METHODS: Concepts were isolated from 3 different types of clinical pathology documents: 1) a textbook (Textbook), 2) the Results sections of industry pathology reports (Findings), and Discussion sections from industry pathology reports (Discussion). Concepts were matched (mapped) by 2 reviewers to semantically-equivalent SNOMED concepts. A quality score of 3 (good match), 2 (problem match), or 1 (no match) was recorded along with the SNOMED hierarchical location of each mapped concept. Results were analyzed using Cohen's Kappa statistic to assess reviewer agreement and chi-square tests to evaluate association between document type and quality score. RESULTS: The percentage of good matches was 48.3% for the Textbook, 45.4% for Findings, and 47.5% for Discussion documents, with no significant difference among documents. Of remaining concepts, 40% were partially expressed by SNOMED and 14% did not match. Mean reviewer agreement on quality score assignments was 76.8%. CONCLUSIONS: Although SNOMED representation of veterinary clinical pathology content was limited, missing and problem concepts were confined to a relatively small area of terminology. This limitation should be addressed in revisions of SNOMED to optimize SNOMED for veterinary clinical pathology applications.  相似文献   
108.
The efficacy and tolerability of a marbofloxacin-clotrimazole-dexamethasone otic suspension (MCD) was compared with a standard topical treatment using a phase III clinical trial protocol. In a total of 140 dogs with clinical signs of acute or subacute otitis externa, Staphylococcus, Pseudomonas, Enterobacteriaceae and Malassezia were isolated from samples taken at inclusion to identify the causative pathogen; a further sample was collected in the event of failure or relapse, and from dogs (at day 14) for which Pseudomonas species had been isolated at inclusion. One group received MCD (10 drops per affected ear) once daily and a second received Surolan (containing polymyxin B, miconazole and prednisolone) (5 drops per affected ear), twice daily. Each group received treatment for 7 or 14 days according to the clinical outcome on day 7. Efficacy and tolerability were evaluated on days 7, 14 and, if necessary, 28 for dogs treated for 14 days. The trial demonstrated equivalence of both treatments in terms of efficacy, with a cure rate of 58.3% for MCD and 41.2% for Surolan. Both medications were equally well tolerated by dogs, but MCD was superior in terms of pain relief, decrease in pus quantity and smell, response rate and investigator's assessment on day 14.  相似文献   
109.
Between 1984 and 2004, nine more species or subspecies of spotted fever rickettsiae were identified as emerging agents of tick-borne rickettsioses throughout the world. Six of these species had first been isolated from ticks and later found to be pathogenic to humans. The most recent example is Rickettsia parkeri, recognized as a human pathogen more than 60 years after its initial isolation from ticks. A new spotted fever rickettsia, R. felis was also found to be associated with fleas and to be a human pathogen. Similarly, bacteria within the family Anaplasmataceae have been considered to be of veterinary importance only, yet three species have been implicated in human diseases in recent years, including Ehrlichia chaffeensis, the agent of human monocytic ehrlichiosis, Anaplasma phagocytophilum, the agent of human anaplasmosis (formerly known as "human granulocytic ehrlichiosis agent", E. equi and E. phagocytophila), and finally Ehrlichia ewingii, which causes granulocytic ehrlichiosis in humans. We present here an overview of the various tick- and flea-borne rickettsial zoonoses described in the last 20 years, focusing on the ecological, epidemiological and clinical aspects.  相似文献   
110.
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