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41.
We report the case of a woman who presented with ST elevation and episodes of chest pain, mimicking an acute myocardial infarction. At coronary angiography no sign of coronary stenosis was found and ECG anomalies were related to asymmetric left ventricular hypertrophy and aortic stenosis.  相似文献   
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Approximately 20% of cirrhotic patients with ascites develop umbilical herniation. These patients usually suffer from multisystemic complications of cirrhosis, have a significantly higher risk of infection, and require accurate surveillance– especially in the context of the coronavirus disease 2019 pandemic. The rupture of an umbilical hernia, is an uncommon, life-threatening complication of large-volume ascites and end-stage liver disease resulting in spontaneous paracentesis, also known as Flood syndrome. Flood syndrome remains a challenging condition for clinicians, as recommendations for its management are lacking, and the available evidence for the best treatment approach remains controversial. In this paper, four key questions are addressed regarding the management and prevention of Flood syndrome: (1) Which is the best treatment approach–conservative treatment or urgent surgery? (2) How can we establish the individual risk for herniation and possible hernia rupture in cirrhotic patients? (3) How can we prevent umbilical hernia ruptures? And (4) How can we manage these patients in the conditions created by the coronavirus disease 2019 pandemic?  相似文献   
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Recent investigations suggest that neutrophils may play an important role in the late-phase allergen-induced inflammation in allergic airway diseases. The aim of this study was to evaluate neutrophil chemotaxis, phagocytic activity, and reactive oxygen species (ROS) production in patients with allergic rhinitis and asthma challenged with inhaled Dermatophagoides pteronyssinus. Eighteen patients with allergic rhinitis and 14 with allergic asthma, all sensitized to D. pteronyssinus, as well as 15 healthy individuals underwent bronchial challenge with D. pteronyssinus. Peripheral blood collection and neutrophil isolation were performed 24 h before as well as 7 and 24 h after bronchial challenge. Neutrophils chemotaxis, phagocytic activity, and ROS production were analyzed by flow cytometer. Neutrophil chemotaxis and ROS production were increased, while phagocytic activity was decreased 24 h before challenge in patient groups compared with healthy individuals. After challenge, neutrophil chemotaxis and phagocytic activity increased after 7 and 24 h, when ROS production, only after 24 h. Bronchial allergen challenge had no influence for neutrophils activity in healthy subjects. Activated chemotaxis, phagocytic activity, and ROS production of peripheral blood neutrophils after challenge with D. pteronyssinus reflect an enhanced systemic inflammation in allergic rhinitis and asthma patients with induced late-phase airway inflammation.  相似文献   
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从鸭外周血分离的单核细胞在体外经PHA (5 μg/ml)刺激 2 0h后 ,提取总RNA及mRNA并通过逆转录制备cDNA。采用最近克隆的鸡白细胞介素 2 (ChIL 2 )cDNA序列为探针对cDNA进行Southernblot杂交 ,以识别鸭白细胞介素 2 (DuIL 2 )特异的cDNA序列。从鸭外周血单核细胞中提取的基因组DNA经限制性内切酶BamHI、EcoRI、XbaI消化后 ,以上述探针进行杂交 ,分析DuIL 2基因组序列。结果表明 ,无论是鸭cDNA或基因组DNA ,经Southern杂交后 ,均得到特异性杂交条带 ,证实ChIL 2与DuIL 2具有较高序列同源性。DuIL 2mRNA表达时形成两种转录子 ,大小分别为 95 9bp、 780bp。同鸡γ 干扰素(ChIFN γ )探针产生的杂交信号比较 ,ChIL 2产生的杂交信号相对较弱 ,推测可能和DuIL 2mRNA在上述条件下拷贝数相对较少以及ChIL 2与DuIL 2cDNA序列同源性相对较低有关  相似文献   
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In geometrical terms, tumor vascularity is an exemplary anatomical system that irregularly fills a three-dimensional Euclidean space. This physical characteristic, together with the highly variable vessel shapes and surfaces, leads to considerable spatial and temporal heterogeneity in the delivery of oxygen, nutrients and drugs, and the removal of metabolites. Although these biological features have now been well established, quantitative analyses of neovascularity in two-dimensional histological sections still fail to view tumor architecture in non-Euclidean terms, and this leads to errors in visually interpreting the same tumor, and discordant results from different laboratories. A review of the literature concerning the application of microvessel density (MVD) estimates, an Euclidean-based approach used to quantify vascularity in normal and neoplastic pituitary tissues, revealed some disagreements in the results and led us to discuss the limitations of the Euclidean quantification of vascularity. Consequently, we introduced fractal geometry as a better means of quantifying the microvasculature of normal pituitary glands and pituitary adenomas, and found that the use of the surface fractal dimension is more appropriate than MVD for analysing the vascular network of both. We propose extending the application of this model to the analysis of the angiogenesis and angioarchitecture of brain tumors.  相似文献   
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Medulloblastoma is the most common malignant brain tumor of childhood. Surgery, radiation therapy, and chemotherapy successfully cure many patients, but survivors can suffer long-term toxicities affecting their neurocognitive and growth potential; furthermore, there is no curative therapy in up to 30% of cases, mainly because of our incomplete understanding of many of the underlying molecular and cellular processes. Angiogenesis is a hallmark of the progression of medulloblastoma and, over the last years, investigators have sought to develop effective and less toxic antiangiogenic strategies, including the inhibition or destruction of abnormal blood vessels using either antiangiogenic or vascular disrupting agents. However, the results are conflicting principally because of the complex biology of tumor vasculature and the irregular geometry of the vascular system in real space. In addition, current targets of antiangiogenic therapy, such as vascular endothelial growth factor (VEGF), are thought to be critical for both physiologic and pathologic angiogenesis, and clinical side effects of anti-VEGF therapy are beginning to emerge. We here review the state-of-the-art concerning antiangiogenic targets for medulloblastoma treatment, and discuss the complexity of the vascular system that intrinsically limits the efficacy of current strategies.  相似文献   
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