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Progress in the treatment of inflammatory myopathies is impeded by the lack of suitable animal models. Inflammatory myopathies occur spontaneously in the dog, are a heterogeneous group of disorders, and are more common than in humans. Clinical signs of weakness and muscle atrophy are reliably present, and there are histological and immunohistological similarities to forms of human myositis. In this study, microarray technology followed by quantitative real-time PCR and immunohistochemistry on muscle biopsy sections was used to investigate gene expression in cases of canine inflammatory myopathies. Several genes involved with innate and adaptive immunity were highly upregulated including those that participate in macrophage and dendritic cell activation and migration, and antigen processing and presentation. Other genes including those that participate in B cell growth, development, migration and activation, immunoglobulin genes, genes in pro-inflammatory and anti-inflammatory pathways, and genes involved with tissue remodeling were upregulated. In previous reports utilizing microarray technology in human myositis, there was activation of similar pathways involved in the immune response. This study strengthens the argument that forms of canine myositis may be important animal models of human myositis and suggests useful biomarkers for therapeutic response using the dog in pre-clinical trials.  相似文献   
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OBJECTIVE: To evaluate prognostic factors associated with outcome of dogs with multiple cutaneous mast cell tumors (MCTs) treated with surgery with or without adjuvant treatment. DESIGN: Retrospective case series. ANIMALS: 54 dogs with a minimum of 2 simultaneous, histologically confirmed cutaneous MCTs that had been excised and had adequate staging and follow-up data. PROCEDURE: Medical records from 1998 to 2004 were examined. Outcome was assessed with the Kaplan-Meier product-limit method and log-rank analysis. Prognostic factors evaluated included signalment; number, histologic grade, location, size, local recurrence, and de novo development of MCTs; quality of surgical margins; clinical signs at the time of diagnosis; and use of adjuvant treatment. RESULTS: Medical records of 54 dogs with 153 tumors were included. Median follow-up time was 658 days. Median disease-free interval (1,917 days; range, 11 to 1,917 days) and median survival time (1,917 days; range, 14 to 1,917 days) were not yet reached. The 1- year and 2- to 5-year survival rates were 87% and 85%, respectively. The overall rate of metastasis was 15%. Factors that negatively influenced survival time in the univariate analysis included incomplete excision, local recurrence, size > 3 cm, clinical signs at the time of diagnosis, and use of adjuvant treatment. Presence of clinical signs at the time of diagnosis was the only negative prognostic factor for disease-free interval detected in the multivariate analysis. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that multiple cutaneous MCTs in dogs are associated with a low rate of metastasis and a good prognosis for long-term survival with adequate excision of all MCTs.  相似文献   
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Typhoon Yolanda brought major devastation to the local communities and infrastructure and also reshaped social structures and networks in the Philippines. During the immediate recovery process, bridging, bonding and linking social capital have had differential impacts and outcomes on how communities cope with the aftermath of the disaster. This article investigates the interplay between the various types of social capital and their contributions to immediate coping strategies of Typhoon Yolanda communities. This article also evaluates the complexity of defining social capital in a disaster context. In particular, it unpacks the blurring of the bridging and linking social capital at the immediate stage of rehabilitation in a post‐disaster context and its impacts on the social fabric of the communities. We deduce from this case study the social capital strategies necessary for a speedy recovery process both economically and socially for disaster‐affected communities.  相似文献   
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Many patterns in biological systems depend on the exchange of chemical signals between cells. We report a spatiotemporal pattern mediated by hydrodynamic interactions. At planar surfaces, spermatozoa self-organized into dynamic vortices resembling quantized rotating waves. These vortices formed an array with local hexagonal order. Introducing an order parameter that quantifies cooperativity, we found that the array appeared only above a critical sperm density. Using a model, we estimated the hydrodynamic interaction force between spermatozoa to be approximately 0.03 piconewtons. Thus, large-scale coordination of cells can be regulated hydrodynamically, and chemical signals are not required.  相似文献   
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Heterothallism in biflagellate aquatic fungi: preliminary genetic analysis   总被引:1,自引:0,他引:1  
Genetic analysis of several hundred progeny from crosses of two heterothallic species of Achlya and Dictyuchus provides preliminary information about the life cycle and pattern of sexuality in the biflagellate Phycomycetes. Extensive testing of mycelial progeny indicates a diploid life cycle. Control of sexual expression and mating competence appears to be based on a complex genetic system.  相似文献   
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Abstract

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Robins and Shapcott (1954 Robins, J. H. and Shapcott, R. 1954. N.Z. vet. J., 2: 5555. [Taylor &; Francis Online] [Google Scholar]) recorded cases of presumed acorn poisoning in sheep.  相似文献   
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