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Journal of Gastroenterology - Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is categorized into four distinct types: the gastric, intestinal, pancreatobiliary, and oncocytic. Each...  相似文献   
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Background We have reported that percutaneous radiofrequency ablation (RFA) with balloon occlusion of the hepatic artery (balloon-occluded RFA), using an expandable electrode, increases the coagulation area. In this study, we investigated the efficacy of balloon-occluded RFA and balloon-microcatheter-occluded RFA, using a cool RF single electrode.Methods We studies 41 patients with 47 hepatocellular carcinoma (HCC) lesions. We treated 28 patients (32 nodules) with balloon-occluded RFA, 5 patients (6 nodules) with balloon-microcatheter-occluded RFA, and 8 patients (9 nodules) with standard RFA. Initial therapeutic efficacy was evaluated with dynamic computed tomography performed 1 week after one session of treatment.Results One session of treatment was done for 20 nodules (62.5%) in the balloon-occluded RFA group and for 4 nodules (66.7%) in the balloon-microcatheter-occluded RFA group. We compared the coagulation diameter for balloon-occluded RFA (7 nodules), balloon-microcatheter-occluded RFA (6 nodules), and standard RFA (9 nodules) after one application cycle (12min). The greatest dimension of the area coagulated by balloon-occluded RFA was significantly larger (greatest long-axis dimension, 47.6 ± 7.8mm; greatest short-axis dimension, 33.4 ± 7.5mm) than that coagulated by standard RFA (greatest long-axis dimension, 35.3 ± 4.7mm; greatest short-axis dimension, 25.9 ± 3.7mm; P = 0.002 for greatest long-axis dimension; P = 0.041 for greatest short-axis dimension). However, there was significant difference only in the greatest short-axis dimension of the area coagulated comparing balloon-microcatheter-occluded RFA and standard RFA.Conclusions We consider balloon-occluded RFA using a cool RF electrode to be superior to standard RFA for the treatment of HCC, especially when larger coagulation volumes are required.  相似文献   
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The state of MRSA contamination of inpatients, hospital staff, and the hospital environment was evaluated. Nasal, pharyngeal, and digital samples from 182 patients admitted in September and October, 1990, and 288 hospital staff members and sputum, urine, and feces of the inpatients were cultured. Environmental contamination was examined in samples collected from the air by air sampling and from the floor by the wiping method. The MIC and the coagulase type of the MRSA obtained were determined, and their relationships were evaluated. MRSA was detected in 9.5% of nasal samples, 7% of pharyngeal samples, 10% of sputum samples, 0% of urine samples, and 2.6% of fecal samples from the 182 inpatients. It was detected in 4% of nasal samples, 0.7% of pharyngeal samples, and 1% of digital samples from the 288 hospital staff members. From the environment, MRSA was detected from hospital rooms of the surgery and neurosurgery wards, the nursing room and corridors of the obstetrics and gynecology ward, and the recovery room of the urology ward. The coagulase type of the MRSA obtained was the primarily type II regardless or whether the samples were obtained from the subjects or the environment. Concerning the drug sensitivity, many MRSA strains were highly resistant to DMPPC and FOM, but the sensitivity to RFP was 0.1 microgram/ml or less in all strains except for one highly resistant strain (200 micrograms/ml or above).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Odontology - There is no conclusive evidence regarding a causal relationship between periodontitis and atherosclerosis. In this study, we examined the microbiome in the oral cavity and atheromatous...  相似文献   
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BACKGROUNDSchwannoma of the pancreas is extremely rare. We report a case of pancreatic schwannoma that was difficult to distinguish from pancreatic carcinoma before surgery.CASE SUMMARYA 66-year-old male underwent a right-lobe hepatectomy for hepatocellular carcinoma. Post-surgical computed tomography showed a 10 mm long solid mass with ischemia, with no expansion into the main pancreatic duct. Upon magnetic resonance cholangiopancreatography, the tumor had high signal intensity in diffusion weighted images, consistent with pancreatic carcinoma. Endoscopic ultrasound (EUS) was performed to obtain more information about the tumor, and showed a 14 mm solid and hypoechoic mass in the pancreatic body. Contrast enhanced EUS revealed that the tumor showed a hyperechoic mass in the early phase, and the contrasting effect continuation was very short; findings also consistent with pancreatic carcinoma. Thus, we preoperatively diagnosed his condition as a pancreatic carcinoma and performed distal pancreatectomy with splenectomy. Microscopic examination showed that the tumor was in fact a benign schwannoma. Histology showed a proliferation of spindle-shaped cell in a vague fascicular and haphazard pattern, with palisading arrangement.CONCLUSIONSchwannoma of the pancreas is very rare, however, clinicians should consider schwannoma as the differential diagnosis for pancreatic tumors.  相似文献   
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Reactive hyperemia reflects a compensatory vasodilation response of the local vasculature in ischemic tissue. The purpose of this study is to clarify the mechanism of regulation of this response in gingival circulation by using pharmacological analysis of reactive hyperemia and histochemical analysis of gingival tissue. Application of pressure to the gingiva was used to create temporary ischemia, and gingival blood flow was measured after pressure release. Reactive hyperemia increased in proportion to the duration of pressure. Systemic hemodynamics remained unaffected by the stimulus; therefore, the gingival reactive hyperemia reflected a local adjustment in circulation. Gingival reactive hyperemia was significantly suppressed by nitric oxide (NO) synthase inhibitors, especially the neural NO synthase-selective antagonist 7-nitroindazole, but not by anticholinergic drugs, β-blockers, or antihistaminergic drugs. Moreover, immunohistochemical staining for neural NO synthase and histochemical staining for NADPH diaphorase activity were both positive in the gingival perivascular region. These histochemical and pharmacological analyses show that reactive hyperemia following pressure release is mediated by NO-induced vasodilation. Furthermore, histochemical analysis strongly suggests that NO originates from nitrergic nerves. Therefore, NO may play an important role in the neural regulation of local circulation in gingival tissue ischemia.  相似文献   
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