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51.
Changes in the nerve fibers of the spinal cord were studied in rat experimental epidural tumor models. Light microscopy showed demyelinization in all with rats paraparesis and paraplegia. Cross-sectional views of nerve fibers stained with 3,3dipentyloxacarbo-cyanine iodide, obtained by confocal laser scanning microscopy, showed distorted, shrunken fibers with a low fluorescence intensity. Changes in the electrolyte contents of nerve fibers were studied by electron probe X-ray microanalysis. The K concentration in axons and the myelin sheath was increased in the paraparesis group, but was decreased in the paraplegia group. These findings suggest that, in the paraparesis group, compression of the spinal cord damaged cell membrane channels, which subsequently caused an increase in intracellular K, a decline in the action potential, and low-intensity fluorescence of nerve fibers. On the other hand, in the paraplegia group, destruction of cell membranes caused a decrease in intracellular K until it approached the extracellular level. This reduced both the action potential and the fluorescence intensity. As Ca and Mg concentrations in both axons and the myelin sheath increased in relation to the severity of neurologic damage, it appears that these electrolytes may also play an important role in damage to nerve fibers.  相似文献   
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Two patients with mucosal cancer of the periampullary region were treated with papillocholedochectomy, which entails removal of the papilla of Vater and the whole length of the common bile duct. The neoplasm is dissected out through the plane between the duodenal circular and longitudinal muscles, deep to the sphincter of Oddi and the fibromuscular layer of the bile duct. Pathological examination showed that cancer was confined to the mucosal layer without stromal invasion, and that the operation achieved radical cure. For mucosal cancer, papillo-choledochectomy is an alternative to pancreatoduodenectomy, provided that repeated frozen-section studies confirm the completeness of excision.  相似文献   
54.
A 42-year-old man was admitted to another hospital complaining of acute abdominal pain that was induced by eating. Abdominal computed tomography and selective angiography revealed an intimal flap separating true and false lumens that was located 3 cm from the origin of the superior mesenteric artery (SMA). Emergency surgery was performed because of the sudden recurrence of diffuse abdominal pain after eating and abdominal aorta-SMA bypass grafting was done using a radial artery graft. Postoperative angiography revealed that the graft showed good patency. The postoperative course was uneventful and abdominal pain no longer occurred after eating. This excellent result was achieved by early diagnosis using CT scanning and angiography plus an aggressive surgical repair with a radial artery bypass graft for isolated dissection of the superior mesenteric artery.  相似文献   
55.
We report a rare successful surgical repair of a common atrium (CA) with mild tricuspid valve (TV) regurgitation due to valvular annulus enlargement in a 39-year-old man, who had a complete atrial septum defect (ASD) without the characteristic of an endocardial cushion defect. The left-to-right shunt ratio was 85 percent and the Qp/Qs was 6.7 due to the CA. Left ventriculogram revealed no evidence of typical goose-neck deformity and no mitral valve regurgitation. The operation consisted of making a new atrial septum with an autologous pericardial patch and tricuspid annuloplasty (DeVega) using extracorporeal circulation. There was no evidence of a cleft on the anterior leaflet of the mitral valve or the septal leaflet of the TV. The postoperative echocardiogram showed no residual shunt flow through a new atrial septum and no TV regurgitation, and atrioventricular (AV) dissociation did not occur. We consider this procedure to be widely applicable in consideration of the favorable results obtained after surgical treatment.  相似文献   
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Transabdominal resection for esophagocardial cancer and reestablishment of alimentary continuity using bypass methods were performed in 76 patients. Thirteen underwent a bypass with a gastric tube and in 30, a colonic segment was prepared. In the remaining 33, a jejunal segment was used as a bypass organ, with considerable success. The 5 year survival rates were 68.8 per cent in those with stages (I+II), 16.5 per cent in those with stage III, 12.6 per cent in those with stage IV and 22.5 per cent in all cases, indicating similar results compared to those with cancer located in the upper third of the stomach with the limited proximal extension within the esophagocardial junction and operated on during the same period.  相似文献   
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Between 1950 and 1986, 14 cases of primary carcinoma of the fallopian tube were treated and diagnosed at the Cancer Institute Hospital. These cases constituted 0.13% of the total number of gynecologic malignancies at the hospital during the period. The clinical/pathological findings and prognoses were described. Of the 14 cases, the average age was 56.0 years. The most frequent symptom was atypical genital bleeding, seen in 11 cases (79%). Massive watery discharge was seen in four cases (29%). In preoperative cytologic examination of vaginal smears, six cases (43%) were positive for cancer. All cases underwent operation as therapy. Postoperative irradiation, adjuvant chemotherapy, and/or second-or third- look operation was also used. Histopathologically, all materials were found to be adenocarcinoma. Four cases were well differentiated, seven were moderately differentiated, and three were poorly differentiated. Two patients with stage III and IV cancers died of the disease. Nine patients were still alive at the end of this study. The five-year survival rate was 57% (4/7). In stage I cancers, the five-year survival rate was 80% (4/5). The prognosis of stage I cancer patients was estimated as rather good.  相似文献   
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