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Five patients underwent reoperations because residual or recurrent aortic regurgitation occurred after aortic valvuloplasty for aortic regurgitation associated with ventricular septal defect. The mean age at reoperation was 22 years old, and the mean time interval between initial and second operation was 6 years, 10 months. The pathological findings of the aortic valves showed tears and perforation of repaired leaflets in four patients and a giant pseudoaneurysm of the Valsalva sinus in one. Aortic valvuloplasties were performed again in three patients, and aortic valves were replaced with prosthetic valves in two. Slight to moderate regurgitant murmurs are still audible in patients who underwent these valvuloplasties. Ventricular septal defects should be closed before aortic regurgitation develops. If it has developed, however, valvuloplasty should be considered as a first choice in young patients. For adult patients, aortic valve replacement is recommended.  相似文献   
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An operative technique for mitral valve replacement (MVR) with preservation of the chordae tendineae to the anterior leaflet as well as the posterior leaflet is reported. This technique consists of the division of the anterior leaflet into anterior and posterior segments, the shifting and reattachment of the divided segments to the mitral ring of the respective commissural areas, and the use of a low-profile bileaflet prosthetic valve. A comparison of left ventricular function data between patients having operation with this technique and those having operation with the conventional method of MVR revealed significantly better improvement in cardiac index (p less than 0.06), left ventricular end-systolic volume index (p less than 0.05), and left ventricular ejection fraction (p less than 0.10) in the former group. Left ventricular wall motion improved in the anterolateral (p less than 0.01) and apical areas (p less than 0.02) in patients operated on with our technique. Maintenance of continuity between the mitral annulus and papillary muscles is expected to have a beneficial effect on postoperative left ventricular performance in spite of increased afterload.  相似文献   
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In 268 of the 1,115 patients (24.0%) with gastric cancer who underwent a curative resection in our clinics, the tumor was located in the middle third of the stomach. The clinicopathological features and prognosis of these patients were divided into two groups, according to site of the tumor: anterior wall (n = 58) vs. other sites (n = 210). Clinicopathological factors did not differ between the two groups. The survival time for patients with a tumor in the anterior group was shorter than that for patients with a tumor in other areas (P < 0.05). The five-year survival rate was 79.3% for patients with an anterior tumor and 91.9% for those with a tumor at a different site. A multivariate analysis indicated lymph node metastasis, serosal invasion, and anterior wall location to be independent prognostic factors indicative of a poor prognosis when the tumor was located in the middle third of the stomach. For such patients, close follow-up is needed to detect possible recurrences. © 1993 Wiley-Liss, Inc.  相似文献   
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While nonspecific airway hyperresponsiveness (AHR) is a central feature of allergic bronchial asthma, the mechanism underlying the development of AHR is not clearly understood. We have previously demonstrated in vitro hyperresponsiveness of bronchial smooth muscle to acetylcholine (ACh) in rats that were actively sensitized and repeatedly challenged with aerosolized antigen. It has also been demonstrated that the ACh-induced, RhoA-mediated Ca(2+) sensitization is markedly augmented concomitantly with an increased expression and activation of RhoA protein in the bronchial smooth muscle of the antigen-treated rats. In the present study, we have investigated whether TNF-alpha, a proinflammatory cytokine which is involved in bronchial asthma, causes upregulation of RhoA mRNA and protein in the rat bronchus. Treatment of rat bronchial smooth muscle preparations with TNF-alpha (300 ng/ml for 24 hr) significantly shifted the concentration-response curve to ACh upwards, but did not alter the response to high K(+), when compared to that of control tissues. Levels of RhoA mRNA and protein in the TNF-alpha-treated bronchus were significantly greater than those in the control group. In conclusion, it is suggested that the augmentation of the ACh-induced contractile response evoked by TNF-alpha might be mediated by an upregulation of RhoA in rat bronchial smooth muscle.  相似文献   
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Islet allotransplantation can achieve insulin independence in patients with type I diabetes. Recent reports show that the two-layer method (TLM), which employs oxygenated perfluorochemical (PFC) and UW solution, is superior to simple cold storage in UW for pancreas preservation in islet transplantation. However, UW solution has several disadvantages, including the inhibition of Liberase activity. In this study, we investigated the features of a new solution, designated M-Kyoto solution. M-Kyoto solution contains trehalose and ulinastatin as distinct components. Trehalose has a cytoprotective effect against stress, and ulinastatin inhibits trypsin. In porcine islet isolation, islet yield was significantly higher in the M-Kyoto/PFC group compared with the UW/PFC group. There was no significant difference in ATP content in the pancreas between the two groups, suggesting that different islet yields are not due to their differences as energy sources. Compared with UW solution, M-Kyoto solution significantly inhibited trypsin activity in the digestion step; moreover, M-Kyoto solution inhibited collagenase digestion less than UW solution. In conclusion, the advantages of M-Kyoto solution are trypsin inhibition and less collagenase inhibition. Based on these data, we now use M-Kyoto solution for clinical islet transplantation from nonheart-beating donor pancreata.  相似文献   
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This report describes our experience with a 60 year old male who suffered from a recrudescence of groove pancreatitis. He had been treated by conservative medication therapy by proton pump inhibitor used for therapy of duodenal ulcer, and was in remission. During a follow-up one year later, endoscopy revealed gastric cancer, for which a proximal gastrectomy and vagotomy were performed. The patient continues to remain in remission for the groove pancreatitis. Our experience with the clinical course of this disease, in which treatment for duodenal ulcer was used effectively, offers new insights into the progression and therapy of groove pancreatitis.  相似文献   
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