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Background  Pancreatic redo procedures belong to the most difficult abdominal operations because of altered anatomy, significant adhesions, and the potential of recurrent disease. We report on our experience with 15 redo procedures among a series of 350 consecutive pancreatic operations. Patient and Methods  From January 1, 2004 to May 31, 2006 a total of 350 patients underwent pancreatic surgery in our department. There were 15 patients identified who had pancreatic redo surgery for benign (14) or malignant (1) disease. Perioperative parameters and outcome of 15 patients undergoing redo surgery after pancreatic resections were evaluated. Results  Operative procedures included revision and redo of the pancreaticojejunostomy after resection of the pancreatic margin (6), completion pancreatectomy (3), conversion from duodenum-preserving pancreatic head resection to pylorus-preserving pancreaticoduodenectomy (3), classic pancreaticoduodenectomy after nonresective pancreatic surgery (1), redo of left-sided pancreatectomy (1), and classic pancreaticoduodenectomy after left-sided pancreatectomy (1). Histology revealed chronic pancreatitis in 14 and a mucinous adenocarcinoma of the pancreas in 1 patient. Median operative time was 335 min (235–615 min) and median intraoperative blood loss was 600 ml (300–2,800 ml). Median postoperative ICU stay was 20 h (4–113 h) and median postoperative hospital stay was 15 days (7–30 days). There was no perioperative mortality and morbidity was 33%. Conclusion  Pancreatic redo surgery can be performed with low morbidity and mortality. Redo surgery has a defined spectrum of indications, but to achieve good results surgery may be performed at high-volume centers.  相似文献   
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High-resolution P-31 MR spectra were obtained in four patients with bone tumors of their distal extremities. In one case the tumor, a Ewing sarcoma of the tibia, was investigated during clinical remission after radiation therapy and chemotherapy. The other three cases - one low-grade chondrosarcoma of the tibial head, one malignant fibrous histiocytoma of the tibia, and one chondroblastoma of the medial femoral condyle - showed clinically active tumor growth, with corresponding increased metabolism as demonstrated by bone scintigraphy. The spectra of the three active tumors indicated a comparably high adenosine triphosphate content, similar to previously published spectra from animal tumors or human tumors implanted into animals. There were also high resonances of inorganic phosphate and low resonances of phosphocreatine; there were definite peaks in the phosphodiester and phosphomonoester regions, indicating the existence of these metabolites in the tumors. Slight but definite changes in the metabolite content were observed in one tumor after chemotherapy. The spectra of the unaffected leg did not show any well-resolved P-31 signals, which is typical for healthy bone. These are the first P-31 MR spectra of human bone tumors measured in patients to our knowledge.  相似文献   
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Abdominal radiography, excretory urography, retrograde pyelography, and computed tomography were performed in two patients who had undergone retrograde pyelography with thorium dioxide (Thorotrast) approximately 40 years ago. Both patients developed a transitional cell carcinoma due to suburothelial thorium deposition. Typical thorium densities were demonstrated at CT in the peripelvicalyceal area as well as in retroperitoneal lymph nodes. Elderly patients in whom radiographic examination reveals retained Thorotrast in the kidney should be followed up because of the high risk of renal carcinoma.  相似文献   
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Cyclic AMP reduction of frequency following ability in peripheral axons   总被引:1,自引:0,他引:1  
Radioimmunoassays for cAMP demonstrated that a beta-adrenergic agonist, isoproterenol, increased cAMP levels in isolated frog sciatic nerve. Dibutyryl cAMP (db-cAMP) and isoproterenol reduced the amplitude of the compound action potential and decreased the ability of the Xenopus sciatic nerve to follow high frequency stimulation. Similar effects of db-cAMP and a phosphodiesterase inhibitor were seen on intracellularly recorded action potentials of single lobster peripheral axons. These results suggest that cAMP can modulate the electrophysiological response properties of both myelinated and unmyelinated axons.  相似文献   
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