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A 49-year-old man with diabetes mellitus and alcoholic liver cirrhosis presented with dyspnoea and fever. A chest computed tomography scan revealed three areas of loculated pleural effusion. Initially, the patient was thought to have an intrapleural empyema and was treated with intravenous antibiotics and closed drainage. However, as he did not improve, he was then treated with open drainage. During open drainage, the patient was diagnosed to have an extrapleural empyema and improved following open drainage treatment.  相似文献   
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Although the genetic basis for gallbladder carcinogenesis has not been clarified, considerable evidence has shown that genetic alterations play an important role in the development and progression of human cancers. In this study, we analyzed 30 gallbladder carcinomas to investigate the role of genetic alterations in their tumorigenesis, and to study correlations with their clinicopathological features. Tissue samples were obtained from 30 patients with gallbladder carcinoma (11 men and 19 women; mean age, 62 years; age range, 38–80 years). Genomic DNAs were extracted from fresh tumor tissue. We examined loss of heterozygosity (LOH) in the p53, APC, DCC, RB, and NM23-H1 gene regions by polymerase chain reaction (PCR)-LOH assay using an automated fluorescent DNA sequencer employing four microsatellite markers (p53, APC, DCC, NM23-H1). Five additional microsatellite markers were used for the determination of microsatellite instability (MSI). LOH was found at p53 in 9 of 15 informative cases (60%), at DCC in 10 of 22 (45%), at APC in 5 of 15 (33%), at RB in 1 of 8 (13%), and at NM23-H1 in 1 of 15 (7%). MSI was observed in 5 of 30 cases (17%) in at least one chromosomal loci of these nine microsatellite markers. None of the patients with MSI-positive tumors showed lymph node metastasis, and there was an inverse correlation between MSI and the presence of LOH in gallbladder carcinoma. These results suggest that there are two independent genetic pathways in gallbladder carcinogenesis; that is, an MSI pathway and an LOH pathway. Received: December 24, 1999 / Accepted: May 26, 2000  相似文献   
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Background Endoscopic ultrasonography-guided fine-needle aspiration biopsy (EUS-FNAB) has come into widespread use, mainly in Western countries, as an efficient and safe method for the cytologic or histologic diagnosis of pancreatic cancer. However, it still has received relatively little attention in Japan. To evaluate the clinical status of EUS-FNAB in Japan, we retrospectively analyzed the results with regard to the ability of EUS-FNAB to diagnose pancreatic cancer, as well as its safety. Methods A total of 52 patients (37 male, 15 female; mean age, 62.5 years; range, 33–85 years) with focal pancreatic lesions underwent EUS-FNAB at our group of hospitals in one region of Japan. Final diagnosis was confirmed by histologic examination of surgical specimens or clinical follow-up. Results The final diagnoses were malignant tumors in 32 patients and benign ones in 20. Insertion of the needle into the lesion was successful in 50 of the 52 patients (96.2%). Adequate specimens were obtained by EUS-FNAB from 47 of the 50 pancreatic lesions (94.0%). With five false-negative and no false-positive results, the accuracy, sensitivity, specificity, and positive and negative predictive values were 89.4%, 82.1%, 100%, 100%, and 79.2%, respectively. No complications occurred. Conclusions EUS-FNAB is an efficient and safe method for the histologic diagnosis of pancreatic cancer. It should be considered as one of the indispensable modalities for the histological diagnosis of pancreatic cancer in Japan, as it is in Western countries.  相似文献   
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Identifying anatomical variations of the celio-mesenteric arterial branches is important when performing pancreaticoduodenectomy. A relatively rare variation is the common hepatic artery entirely originated as a branch of the superior mesenteric artery. This type of variation is termed hepatomesenteric trunk type common hepatic artery, in which an accessory left hepatic artery arising from the celiac trunk is absent. Preservation of hepatomesenteric trunk type common hepatic artery is indispensable during pancreaticoduodenectomy because fatal hepatic injury or leak of hepaticojejunostomy can occur. The present case report shows a patient with pancreatic head tumor in whom hepatomesenteric trunk type common hepatic artery was involved by the tumor. The patient underwent pancreaticoduodenectomy during which the involved hepatomesenteric type common hepatic artery was removed and reconstructed using saphenous venous grafts. Histopathological examination showed double cancers which were composed of an advanced ductal adenocarcinoma of the pancreas and early bile duct adenocarcinoma. The patient is alive 18 months after the surgery without recurrence.  相似文献   
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Oxidative stress is presumed to be involved in the pathogenesis of many diseases, including cardiovascular disease. However, oxidants are also generated in healthy cells, and increasing evidence suggests that they can act as signaling molecules. The intracellular reduction-oxidation (redox) status is tightly regulated by oxidant and antioxidant systems. Imbalance between them causes oxidative or reductive stress which triggers cellular damage or aberrant signaling, leading to dysregulation. In this review, we will briefly summarize the aspects of ROS generation and neutralization mechanisms in the cardiovascular system. ROS can regulate cell signaling through oxidation and reduction of specific amino acids within proteins. Structural changes during post-translational modification allow modification of protein activity which can result in altered cellular function. We will focus on the molecular basis of redox protein modification and how this regulatory mechanism affects signal transduction in the cardiovascular system. Finally, we will discuss some techniques applied to monitoring redox status and identifying redox-sensitive proteins in the heart. This article is part of a Special Section entitled "Post-translational Modification."  相似文献   
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Background and Objectives Our previous report showed that parvovirus B19 genotype 1 in different solutions derived from plasma preparations showed different heat‐sensitivity patterns during liquid‐heating. In this study, we similarly examined B19 genotype 2. Materials and Methods Two plasma samples one containing B19 genotype 1 and the other genotype 2 DNA were used. Four process samples collected immediately before the heat treatment step in the manufacture of albumin, immunoglobulin, haptoglobin and antithrombin preparations were spiked with B19 and subsequently treated at 60°C for 10 h. A low pH immunoglobulin solution was also spiked with B19 and treated at room temperature for 14 days. Infectivity was then measured. Results B19 genotype 2, similar to genotype 1, showed three patterns of inactivation: (i) a rapid inactivation in the albumin and immunoglobulin preparations, (ii) a slow inactivation in the haptoglobin preparation and (iii) only limited inactivation in the antithrombin preparation. Its sensitivity in the low pH immunoglobulin solutions also resembled that of genotype 1. Conclusion Both genotypes 1 and 2 of B19 varied in sensitivity to liquid‐heating and low pH among different plasma preparations.  相似文献   
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