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71.
Sclerosing mediastinitis is a very rare benign disorder characterised by the development of dense fibrous tissue within the mediastinum. Affected patients are typically young adults with infant cases being uncommon especially in areas without endemic histoplasmosis. We report a Japanese boy with markedly elevated serum inflammatory markers for more than 1 year in the absence of any clinical manifestations. 67Ga-scintigraphy demonstrated an accumulation in the mediastinal region and an open biopsy revealed a hard fibrous mass in the anteriosuperior mediastinum. Thus, a diagnosis of idiopathic sclerosing mediastinitis was made. Conclusion:To the best of our knowledge, this case is the youngest patient reported with this disorder. In patients with mediastinal mass lesions the diagnosis of sclerosing mediastinitis should be considered as well as infectious, autoimmune or neoplastic disease even in children.  相似文献   
72.
The aim of the present study was to examine the factors that contribute to the postmortem lung weight in acute fire fatalities (n=149) including those with lower (<60%) and higher (>60%) blood carboxyhemoglobin (COHb) levels (n=94 and 55, respectively). The control groups consisted of acute myocardial infarction/ischemia (AMI, n=99) and mechanical asphyxiation (n=85). For all cases (n=333), the lung and heart weights were independent of the postmortem time (4.5-72 h) and charring of the body. The combined weight of both lobes of the lung showed a significant gender difference (males>females, P<0.001), negative regression with respect to age (R=0.167, P<0.01) and positive regression with respect to heart weight (R=0.316, P<0.001). The gender difference was also significant for each cause of death even after being corrected using body height measurements. When the lung-heart weight ratio was estimated to diminish the influence of possible cardiogenic factors, the gender difference was insignificant for each cause of death among the non-elderly (<60 years of age). However, for elderly fire fatalities (>60 years of age), there was a gender difference (males>females) for the lower COHb group (P<0.05) and higher COHb group (P<0.001). A significant age-dependent difference (non-elderly>elderly) in the lung-heart weight ratio was observed for fire fatalities with a lower COHb and AMI among males and for fire fatalities with a higher COHb among females. Such gender- and/or age-dependent influences were not significant for fatal mechanical asphyxiation. These findings suggest that a person's heart weight may be a possible contributory factor to an increase in the lung weight in acute death, and that gender- and/or age-dependent susceptibilities may be additional factors that contribute to fire fatalities and AMI. In addition, elderly females appear to be most susceptible among fire casualties, and extreme cardiomegaly may also be a potential fatal risk factor.  相似文献   
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Callysponginol sulfate A (1) was isolated from the marine sponge Callyspongia truncata as a membrane type 1 matrix metalloproteinase (MT1-MMP) inhibitor. Its structure was elucidated by a combination of spectroscopic and chemical methods and found to be a new sulfated C(24) acetylenic fatty acid. Compound 1 inhibited MT1-MMP with an IC(50) of 15.0 microg/mL.  相似文献   
75.
Apoptosis is induced by many kinds of therapy-related inducers, such as hyperthermia and chemotherapeutic agents. However, differences in apoptotic pathways between these inducers remain unclear, although knowing the differences is important to map out a therapeutic strategy. Therefore, we focused on the localization and phosphorylation of Bcl-2 and Bax, key mediators of the apoptotic pathway, after hyperthermia and paclitaxel treatment of PC-10 squamous cell carcinoma cells that excessively expressed Bcl-2 and Bax in the cytoplasm. Paclitaxel treatment markedly induced qualitative changes in Bcl-2, whereas hyperthermia did only quantitative changes in Bax. The levels of Bax increased gradually with the duration of hyperthermia, whereas Bcl-2 levels slightly decreased. On the other hand, paclitaxel treatment induced dose- and time-dependent phosphorylation of Bcl-2. Interestingly, phosphorylated Bcl-2 was observed in the specific subcellular sites, mitochondria- and lysosome-rich fractions. Both treatments disturbed the heterodimerization of Bax with Bcl-2. Hyperthermia, but not paclitaxel treatment, induced a gradual Bax translocation from the cytoplasm to the nucleus. Although both treatments induced a prominent cell cycle disturbance in the G2M phase, paclitaxel treatment induced typical apoptosis, and hyperthermia hardly induced apoptosis. Our results suggest that the subcellular redistribution of Bax and the phosphorylation of Bcl-2 depend on the type of apoptosis inducers, such as hyperthermia and paclitaxel, and Bcl-2 has a central role in the decision of apoptotic outcome. Our data may afford new insights in apoptosis from the aspect of an association of Bcl-2 phosphorylation with intracellular Bax localization.  相似文献   
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We present 2 interesting cases of multiple system atrophy in which increased myocardial iodine-123 metaiodobenzylguanidine uptake was observed on delayed images (3 hours after injection) compared with early images (15 minutes after injection). These findings have not been previously described. The duration of symptoms was less than 1 year in both these patients. The mechanism responsible for these findings is not clearly understood, but could be related to the pathophysiological changes in the early stage of multiple systemic atrophy.  相似文献   
79.
Our objective was to evaluate the ability of multiplanar reformatted (MPR) images combined with 0.5-mm axial images to depict the pancreatic and intrapancreatic bile ducts and compare the results with those of 0.5-mm axial, 2-mm axial, and 6-mm axial images alone. Seventy-seven patients without obstruction of the main pancreatic ducts (MPD) underwent dual-phase helical scanning of the pancreas using multislice computed tomography (MSCT). The MPR images were generated from 0.5-mm-thick images. Visualization of the pancreatic and intrapancreatic bile ducts and their confluence was graded on a four-point scale by a consensus of two radiologists. The results for 0.5-mm axial images in early-phase CT, 2-mm axial images in early-phase CT, MPR images combined with 0.5-mm axial images in early-phase CT, and 6-mm axial images in late-phase CT were then compared. The relationships of the focal pancreatic lesions with the pancreatic ducts were analyzed. The MPR images combined with 0.5-mm axial images were significantly superior to the other three types of images for the visualization of the pancreatic and intrapancreatic bile ducts and their confluence (p<0.01). The depiction rate of the MPD using MPR images combined with 0.5-mm axial images was 94, 94, 95, and 75%, respectively in the head, neck, body, and tail of the pancreas. Accessory pancreatic ducts, intrapancreatic bile ducts, and duct confluence were depicted in 48, 99, and 92%, respectively. In comparison with evaluation based on axial images alone, the use of MPR images more clearly demonstrated the relationship between the lesions and the pancreatic ducts in 14 of 19 lesions. The MPR images combined with 0.5-mm axial images improve the CT depiction of the pancreatic and intrapancreatic bile ducts in comparison with 0.5-mm axial, 2-mm axial, and 6-mm axial images alone. Electronic Publication  相似文献   
80.
BACKGROUND: With recent advances in low-dose helical computed tomography (CT), detection of ground-glass opacity (GGO) has increased. The aim of this study was to correlate high-resolution CT (HRCT) findings with pathologic features and to evaluate the efficacy of thoracoscopic limited resection for focal GGO, which were selected based on HRCT findings. METHODS: Focal GGO lesions were classified into two subtypes based on HRCT findings: pure type and mixed type. Ninety-six patients with persistent GGO 2 cm or less in diameter underwent pulmonary resection from January 1997 to December 2001. Among these, thoracoscopic wedge resection was performed prospectively between June 2000 and December 2001 in 33 patients with pure GGO lesions that were 1 cm or less. RESULTS: Thoracoscopic wedge resection was completed with complete safety. The histologic diagnoses of these 33 lesions were adenocarcinoma in 1, bronchioloalveolar carcinoma (BAC) in 23, and atypical adenomatous hyperplasia (AAH) in 9. No patients have had any evidence of tumor recurrence to date. Of the total 96 GGO lesions, 93.0% (53/57) of pure GGO 1 cm or less were BAC or AAH, whereas 38.5% (15/39) of pure GGO larger than 1 cm or mixed GGO were adenocarcinoma. CONCLUSIONS: Pure GGO 1 cm or less was characteristic of noninvasive lesions. Thoracoscopic limited resection for small GGO lesions selected by HRCT was valid.  相似文献   
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