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51.
Quantitative PCR and visual monitoring of Mycosphaerella graminicola epidemics were performed to investigate the effect of curative and preventative applications of azoxystrobin in wheat field crops. A non-systemic protectant and a systemic curative fungicide, chlorothalonil and epoxiconazole, respectively, were used as references. PCR diagnosis detected leaf infection by M graminicola 3 weeks before symptom appearance, thereby allowing a clear distinction between curative and preventative treatments. When applied 1 week after the beginning of infection, azoxystrobin curative activity was intermediate between chlorothalonil (low effect) and epoxiconazole. When applied preventatively, none of the fungicides completely prevented leaf infection. There was some indication that azoxystrobin preventative treatments may delay fungal DNA increase more than epoxiconazole at the beginning of leaf infection. Both curative and preventative treatments increased the time lapse between the earliest PCR detection and the measurement of a 10% necrotic leaf area. Azoxystrobin only slightly decreased the speed of necrotic area increase compared with epoxiconazole. Hence, azoxystrobin activity toward M graminicola mainly resides in lengthening the time lapse between the earliest PCR detection and the measurement of a 10% necrotic leaf area. Information generated in this way is useful for optimal positioning of azoxystrobin treatments on M graminicola. 相似文献
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Olivry T Borrillo AK Xu L Dunston SM Slovis NM Affolter VK Demanuelle TC Chan LS 《Veterinary immunology and immunopathology》2000,73(1):45-52
Bullous pemphigoid (BP) is an autoimmune subepithelial blistering dermatosis of humans, dogs, cats and pigs. It is characterized by skin-fixed and circulating IgG autoantibodies that target one or both BP antigens. An immunological homologue of BP in humans was diagnosed in two horses with cutaneous and mucosal ulcerations as well as microscopic subepithelial vesiculation. Immunological investigations revealed similar findings for both the horses. Direct immunofluorescence demonstrated the presence of IgG deposited linearly at the dermoepidermal junction in mucosal and skin biopsy specimens. Indirect immunofluorescence testing confirmed the existence of circulating basement membrane-specific IgG autoantibodies. Using intact and salt-split epithelial substrates, serum IgG were shown to target antigens situated not only at the basal, but also at the lateral and apical aspects of stratum basale keratinocytes. Immunoblotting and ELISA corroborated that the IgG from affected horses, but not those from normal controls, exhibited high immunoreactivity against the NC16A extracellular domain of type XVII collagen (BPAG2, BP180). Equine BP could be proposed, therefore, as another spontaneous model of this most common basement membrane autoimmune dermatosis of humans. 相似文献
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N. J. Olby K. K. Chan M. P. Targett J. E. F. Houlton 《The Journal of small animal practice》1997,38(5):213-216
A Jack Russell terrier with a history of progressive exercise intolerance was examined at the age of four months and again 10 months later. Clinical examination revealed a stunted, thin dog with a stilted gait. The dog had raised lactate levels before and after feeding and a raised lactate/pyruvate ratio after feeding, indicating a metabolic abnormality. Histochemical evaluation of muscle biopsies revealed subsarcolemmal accumulation of oxidative activity when stained with nicotinamide adenine dinucleotide tetrazolium reductase and ragged red fibres when stained with modified Gomori trichrome; all fibre types were involved. Ultrastructural examination of the muscle confirmed the presence of subsarcolemmal accumulations of mitochondria. Histochemical staining for the activity of enzymes of the Krebs cycle, oxidative phosphorylation and other metabolic cytosolic enzymes failed to demonstrate an abnormality. In view of the clinical picture and the biochemical and histological findings, a tentative diagnosis of mitochondrial myopathy was made. The difficulties associated with diagnosing mitochondrial disorders are discussed. 相似文献
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An angiosarcoma involving the right frontal and maxillary sinuses in a nine-year-old Thoroughbred mare was studied post mortem by light and electron microscopy. Important diagnostic features included malignant endothelial cells lining ill-defined vascular spaces, supported by other vasoformative elements. Rhabdomyoblasts were also found. The tumour is apparently rarely seen in the nasal passages of the horse. 相似文献
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当今世界的农业发展概况 当今世界的农业,广袤、多样且快速变化.如果地方层面、国家层面乃至全球层面都有健全的政策和支持性投入,今天的农业将为数以亿计的农村穷人摆脱贫困提供新的契机.农业向他们敞开脱贫道路包括家庭种植业和养殖业、高附加值的"新型农业"就业机会、新兴的农村非农产业创业和就业机会等等. 相似文献
57.
大学生网络购物心理与行为模式研究——以南京地区为例 总被引:2,自引:0,他引:2
本研究以南京高校在校大学生为调查对象,对影响大学生网络购物意向的因素进行实证研究?并提出了商家如何迎合大学生购物心理的营销建议,以提高网站的营销效果. 相似文献
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