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971.
A 48-year-old woman was admitted to our hospital suffering from chest and back pain. The aortogram and CT scanning revealed aortic dissection (DeBakey II type). Six days after onset, the emergent operation was carried out under the cardio-pulmonary bypass. Myocardial protection was made by retrograde coronary sinus perfusion (RCSP) with cold GIK. The ascending aorta was replaced with an artificial graft including the entry. Massive bleeding in the pericardial space and the rupture of coronary sinus was recognized immediately after declamping of the aorta. Repair was made successfully under induced electric ventricular fibrillation. Care for RCSP was discussed.  相似文献   
972.
Thymolipoma is a very rare mediastinal tumor. We reported a case of 52-year-old female with thymolipoma which was located in the cervicomediastinal area. The chest X-ray film revealed an abnormal shadow in the superior mediastinum. Computed Tomography (CT) clearly showed the existence of a large mass in the left side of the trachea. The angiogram showed that there was a stenosis on the left brachiocephalic vein. On June 13, 1988, median sternotomy was performed. A large tumor, about 5.5 x 13 x 5.5 cm, was found arising from the left cervical area. This tumor was excised completely and thymolipoma was diagnosed histopathologically. The post-operative course was very satisfactory.  相似文献   
973.
Transurethral resection of urinary bladder tumor was performed under spinal anesthesia which has been considered to be rather contraindicated in a patient with idiopathic hypertrophic cardiomyopathy. Caution was exercised not to compromise myocardial oxygen supply demand ratio. Central venous pressure (CVP) was continuously monitored and crystalloid solution was infused to maintain CVP in pre-anesthetic level, thereby preventing the reduction in arterial pressure. The patient was hemodynamically stable throughout the operation. This case indicates that if adequate preload could be preserved and hypotension avoided, spinal anesthesia may not be precluded in patients with idiopathic hypertrophic cardiomyopathy.  相似文献   
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BACKGROUND: Although 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a product of 15-lipoxygenase (15-LO), may be involved in mild to moderate asthma, little is known about its potential roles in severe asthma. OBJECTIVES: This study was performed to evaluate 15(S)-HETE levels in bronchoalveolar lavage fluid (BALF) from severe asthmatics with and without airway eosinophils and from the control groups. In addition, 15-LO protein expression was examined in endobronchial biopsy, while its expression and activation were evaluated in BAL cells. RESULTS: While 15(S)-HETE levels in BALF were significantly higher in all severe asthmatics than normal subjects, severe asthmatics with airway eosinophils had the highest levels compared with mild, moderate asthmatics and normal subjects. 15(S)-HETE levels were associated with tissue eosinophil numbers, sub-basement membrane thickness and BALF tissue inhibitor of metalloproteinase-1 levels, and were accompanied by increased 15-LO expression in bronchial epithelium. In addition, activation of 15-LO was suggested by the increased proportion of 15-LO in the cytoplasmic membrane of alveolar macrophages from severe asthmatics. CONCLUSION: The data suggest that severe asthmatics with persistent airway eosinophils manifest high levels of 15(S)-HETE in BALF, which may be associated with airway fibrosis. It is likely that 15-LO expression and activation by airway cells explain the increased 15(S)-HETE levels.  相似文献   
977.
BACKGROUND: Previous studies have shown that rat peritoneal mast cells and mast cell model rat basophilic leukaemia (RBL-2H3) cells generate intracellular reactive oxygen species (ROS) in response to antigen challenge. However, the physiological significance of the burst of ROS is poorly understood. OBJECTIVE: The present study was undertaken to investigate the role of superoxide anion in mediator release in rat and human cell systems. METHODS: RBL-2H3 cells were directly stimulated with anti-rat FcepsilonRI alpha-subunit monoclonal antibody (mAb). For the analysis of human cell system, leucocytes were isolated by dextran sedimentation from healthy volunteers or from patients, and challenged either with anti-human FcepsilonRI mAb or with the relevant antigens. Superoxide generation was determined by chemiluminescence-based methods. The releases of histamine and leukotrienes (LT)s were determined by enzyme-linked immunosorben assay (ELISA). RESULTS: Cross-linking of FcepsilonRI on RBL-2H3 cells or on human leucocytes from healthy donors by the anti-FcepsilonRI mAb resulted in a rapid generation of superoxide anion, as determined by chemiluminescence using superoxide-specific probes. Similarly, leucocytes from patients generated superoxide anion in response to the challenge with the relevant allergen but not with the irrelevant allergen. Furthermore, diphenyleneiodonium (DPI), a well-known inhibitor of flavoenzymes suppressed the superoxide generation and the release of histamine and LTC4 induced by the anti-FcepsilonRI mAb or by allergen in parallel. CONCLUSION: These results indicate that both RBL-2H3 cells and human basophils generate superoxide anion upon FcepsilonRI cross-linking either by antibody or by allergen challenge and that blockade of the generation prevents the release of allergic mediators. The findings strongly support the role of superoxide generation in the activation of mast cells and basophils under both physiological and pathological conditions. The findings suggest that drugs regulating the superoxide generation have potential therapeutic use for allergic disorders.  相似文献   
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