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Breast metastases from extramammary neoplasms are very rare. We presented a 66 year-old female with metastasis of small cell lung carcinoma to the breast. She presented with consolidation over the left upper lobe of her lung undetermined after endobronchial or video-assisted thoracoscopic surgery (VATS) biopsy, and this was treated effectively after antibiotic therapy at initial stage. The left breast lumps were noted 4 months later, and she underwent a modified radical mastectomy under the impression of primary breast carcinoma. However, the subsequent chest imaging revealed re-growing mass over the left mediastinum and hilum, and cells with the same morphological and staining features were found from specimens oftransbronchial brushing and biopsy. An accurate diagnosis to distinguish a primary breast carcinoma from metastatic one is very important because the therapeutic planning and the outcome between them are different.  相似文献   
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Data driven modeling for power transformer lifespan evaluation   总被引:1,自引:1,他引:0  
Large sized power transformers are important parts of the power supply chain. These very critical networks of engineering assets are an essential base of a nation's energy resource infrastructure. This research identifies the key factors influencing transformer normal operating conditions and predicts the asset management lifespan. Engineering asset research has developed few lifespan forecasting methods combining real-time monitoring solutions for transformer maintenance and replacement. Utilizing the rich data source from a remote terminal unit (RTU) system for sensor-data driven analysis, this research develops an innovative real-time lifespan forecasting approach applying logistic regression based on the Weibull distribution. The methodology and the implementation prototype are verified using a data series from 161 kV transformers to evaluate the efficiency and accuracy for energy sector applications. The asset stakeholders and suppliers significantly benefit from the real-time power transformer lifespan evaluation for maintenance and replacement decision support.  相似文献   
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提出了不同于传统电动力学的直流电能流输运过程解释,指出坡印廷能流的定义不能简单推广到直流电.通过对含欧姆定律的麦克斯韦方程组进行分析,证明了直流电的能流输运过程受扩散方程支配,与波动方程无关;发现经典坡印廷能流的推导过程存在隐含的物理学限制,导致其不适用于金属导体内电磁纵场的做功过程.研究表明,金属导体直流电能的输运过程及其支配方程均与洛伦茨力有关,与坡印廷矢量无关.研究结论可以推广至低频似稳态,从而为电工学和近场电磁学的研究带来广阔的前景.  相似文献   
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A spray drier was designed employing the two-fluid nozzle as, the spraying device complete with a collecter for the powder conveyed by air. No difficulty was encountered in dehydrating the soy-bean milk just as in the case of cow milk. Improving the interaction between .the hot air and the sprayed liquor increased the rate of heat transmission and the percentage of air utilized with higher thermal efficiency as a. result. The thermal efficiency was governed also by the mean temperature difference bet...  相似文献   
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遥感地形资料具有空间离散分布特点,因此根据离散谱空间变换中谱能不变性约束下的谱分析方法,研究了遥感地形谱空间域分布基本特征和地形强迫对大气受迫运动的作用机制.并通过定义地形扰动和地形扰动特征尺度的概念,发现位于青藏高原背风侧的我国中东部地区纬向(东西向)剖面地形扰动特征尺度在454.5km,即该地区地形扰动可以定义为中α尺度扰动(比照大气尺度分类);地形扰动尺度与该地区主要致灾天气系统MαCS(Meso-α Convective System,中α尺度对流系统)尺度上的一致性揭示了地形对于MαCS的触发作用.进一步通过对卫星遥感离散地形场测度进行分形学分析,计算出该区域纬向剖面分数维为1.26,说明该地区地形的基本分形元是Koch三角生成元,即青藏高原背风侧地区剖面地形强迫作用机制本质上是基本西风气流与三角形元组合型山脉剖面障碍物相互作用的结果.这种相互作用的物理图象表现为:在我国青藏高原背风侧地区,冬季和夏季700hPa纬向平均风速扰动谱最强峰与地形扰动谱最强峰存在着明显的地形-纬向风速偶合关系,地形-纬向风速共振模态是该地区冬季纬向环流扰动的典型触发机制;而夏季,地形一纬向风速偶合模态转变为向小尺度漂移的高阻尼模态.同时,地形和纬向风速的分形分析表明,关于地形强迫下的受迫扰动的偶合模态和强迫机制的结论,具有尺度的串级和自相似性,可外推到未观测到的更精细的尺度上.  相似文献   
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Childhood nephrotic syndrome is mainly caused by minimal change disease which is named because only subtle ultrastructural alteration could be observed at electron microscopic level in the pathological kidney. Glomerular podocytes are presumed to be the target cells whose protein sieving capability is compromised by a yet unidentified permeability perturbing factor. In a cohort of children with non-hereditary idiopathic nephrotic syndrome, we found the complement fragment C5a was elevated in their sera during active disease. Administration of recombinant C5a induced profound proteinuria and minimal change nephrotic syndrome in mice. Purified glomerular endothelial cells, instead of podocytes, were demonstrated to be responsible for the proteinuric effect elicited by C5a. Further studies depicted a signaling pathway involving Rho/Rho-associated kinase/myosin activation leading to endothelial cell contraction and cell adhesion complex breakdown. Significantly, application of Rho-associated kinase inhibitor, Y27632, prevented the protein leaking effects observed in both C5a-treated purified endothelial cells and mice. Taken together, our study identifies a previously unknown mechanism underlying nephrotic syndrome and provides a new insight toward identifying Rho-associated kinase inhibition as an alternative therapeutic option for nephrotic syndrome.  相似文献   
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