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71.
OBJECTIVES: Investigate the tolerability, safety, and efficacy of using the lingual mucosal graft (LMG) for anterior urethroplasty. METHODS: Ten patients (average age, 41 yr) underwent substitution urethroplasty LMG. Harvesting the graft from the tongue was performed by either the oral surgeon or the urologist. In five patients with penile urethral strictures, the grafts were placed on the dorsal urethral surface as a "dorsal inlay." In five patients with bulbar urethral strictures, the grafts were used as a "dorsal inlay" (3 cases) or "ventral onlay" (2 cases). The average follow-up was 5 mo (range: 3-12 mo). RESULTS: Nine cases (90%) were successful and one (10%) was a failure. Three patients who underwent bulbar urethroplasty showed prior failed repair using buccal mucosal grafts harvested from a single cheek (1 case), from both cheeks (1 case), or from the lip (1 case). The length of the lingual grafts was 4-6cm (mean: 4.5cm) with a width of 2.5cm. No patient developed early or late postoperative complications on the harvest site related to the tongue surgery. No difference was observed in patients in whom the graft harvesting was performed by the oral surgeon compared to the patients in whom the procedure was performed by the urologist. CONCLUSIONS: The surgical technique for harvesting a graft from the tongue is simple and safe. The tongue may be the best alternative donor site to the lip when a thin graft is required for urethroplasty or when the cheek harvesting is not possible.  相似文献   
72.
OBJECTIVE: To assess the reliability of 18-fluorodeoxyglucose positron emission tomography (18-FDG PET) in distinguishing benign from malignant cystic lesions of the pancreas. SUMMARY BACKGROUND DATA: The preoperative differential diagnosis of cystic lesions of the pancreas remains difficult: the most important point is to identify malignant or premalignant cysts that require resection. 18-FDG PET is a new imaging procedure based on the increased glucose metabolism by tumor cells and has been proposed for the diagnosis and staging of pancreatic cancer. METHODS: During a 4-year period, 56 patients with a suspected cystic tumor of the pancreas underwent 18-FDG PET in addition to computed tomography scanning, serum CA 19-9 assay, and in some instances magnetic resonance imaging or endoscopic retrograde cholangiopancreatography. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value. The accuracy of 18-FDG PET and computed tomography was determined for preoperative diagnosis of a malignant cyst. RESULTS: Seventeen patients had malignant tumors. Sixteen patients (94%) showed 18-FDG uptake with a standard uptake value of 2.6 to 12.0. Twelve patients (70%) were correctly identified as having malignancy by computed tomography, CA 19-9 assay, or both. Thirty-nine patients had benign tumors: only one mucinous cystadenoma showed increased 18-FDG uptake (standard uptake value 2.6). Five patients with benign cysts showed computed tomography findings of malignancy. Sensitivity, specificity, and positive and negative predictive values for 18-FDG PET and computed tomography scanning in detecting malignant tumors were 94%, 97%, 94%, and 97% and 65%, 87%, 69%, and 85%, respectively. CONCLUSIONS: 18-FDG PET is more accurate than computed tomography in identifying malignant pancreatic cystic lesions and should be used, in combination with computed tomography and tumor markers assay, in the preoperative evaluation of patients with pancreatic cystic lesions. A positive result on 18-FDG PET strongly suggests malignancy and, therefore, a need for resection; a negative result shows a benign tumor that may be treated with limited resection or, in selected high-risk patients, with biopsy, follow-up, or both.  相似文献   
73.
Abstract: Background: Radiofrequency ablation (RFA) is an established treatment for hepatocellular carcinoma (HCC) in patients awaiting liver transplantation, due to its comparably low rate of complication and high effectiveness. Complications are thought to be rare and mostly self-limiting. By contrast, we report on a life-threatening complication and discuss it in the context of other complications. Patients and methods: Out of a total of 149 RFA procedures, the incidence of major complications was 4% on a per-procedure basis. Mortality was 0.67%. Major complications included intractable pain, intrahepatic hematoma, skinburn at the site of patch electrode, and sectorial bile duct stricture. All complications occurred after percutaneous RFA. Highlighted is a young patient listed for liver transplantation because of HCC recurrence following hepatic resection, who was treated by percutaneous RFA as a bridging therapy until a suitable graft became available. Post-operatively, gastric perforation occurred due to heat injury of the gastric wall. Conclusions: The percutaneous RFA approach can occasionally lead to detrimental complications, particularly in patients with intra-abdominal adhesions, due to previous surgery if new intrahepatic malignant lesions accrue near the resection margin. Even widespread HCC disease can be treated effectively with orthotopic liver transplantation if the tumor growth is limited to the liver.  相似文献   
74.
Patients with pancreatic cancer often present with advanced disease; so, curative surgical resection is possible in a small number of patients. Palliation in these patients focuses particularly on relief of biliary obstruction. Palliative treatment modalities include both surgical and nonsurgical approaches. Biliary obstruction is initially treated with endoscopic biliary stenting, plastic or metallic stents. Both of these provide similar initial relief of biliary obstruction; however, plastic stents have a greater risk of occlusion and should be used in patients with short survival duration. Metallic stents have a greater initial cost, but provide an overall cost-saving in patients with expected survival more than 6 months. There is no evidence of benefit from routine stenting of jaundiced patients before resection. Surgical palliation for biliary obstruction should be primarily considered in patients who fail endoscopic or percutaneous biliary decompression or who develop gastroduodenal obstruction, It is also indicated for patients with good performance status and expected survival of over 6 months. Surgical decompression of biliary tree should be made with a choledochojejunostomy whenever feasible, associated to a gastroduodenal bypass.  相似文献   
75.
BACKGROUND: We tested the hypothesis that using a subgluteus approach to the sciatic nerve requires a lower concentration of mepivacaine to obtain complete anesthesia as compared with the popliteal approach. METHODS: With midazolam premedication (0.05 mg kg(-1) iv), 48 patients undergoing hallux valgus repair were randomly allocated to receive a sciatic nerve block using either a posterior popliteal (group Popliteal, n = 24) or subgluteus (group Subgluteus, n = 24) approach with 30 mL of local anesthetic injected after elicitation of plantar flexion of the foot with a current 相似文献   
76.
This study evaluated the 1-year survival and success rate of root-analogue direct laser metal sintering (DLMS) implants, placed into the extraction sockets of 15 patients. DLMS is a technology which allows solids with complex geometry to be fabricated by annealing metal powder microparticles in a focused laser beam, according to a computer-generated three-dimensional (3D) model; the fabrication process involves the laser-induced fusion of titanium microparticles, in order to build, layer-by-layer, the desired object. Cone-beam computed tomography (CBCT) acquisition and 3D image conversion, combined with the DLMS process, allow the fabrication of custom-made, root-analogue implants (RAIs). CBCT images of 15 non-restorable premolars (eight maxilla; seven mandible) were acquired and transformed into 3D models: from these, custom-made, root-analogue DLMS implants with integral abutment were fabricated. Immediately after tooth extraction, the RAIs were placed in the sockets and restored with a single crown. One year after implant placement, clinical and radiographic parameters were assessed: success criteria included absence of pain, suppuration, and exudation; absence of implant mobility and absence of continuous peri-implant radiolucency; distance between the implant shoulder and the first visible bone-to-implant contact <1.5 mm from initial surgery; and absence of prosthetic complications. At the 1-year follow-up, no implants were lost, for a survival rate of 100 %. All implants were stable, with no signs of infection. The good conditions of the peri-implant tissues were confirmed by the radiographic examination, with a mean DIB of 0.7 mm (±0.2). The possibility of fabricating custom-made, RAI DLMS implants opens new interesting horizons for immediate placement of dental implants.  相似文献   
77.
BACKGROUND: To study the effect of donor age on kidney function, the authors investigated matched pairs from the same kidney donor given to a pediatric or an adult recipient. METHODS: Fifteen matched pairs of an adult and a pediatric patient, selected from the Eurotransplant registry, receiving the renal graft from the same cadaveric donor were selected for analysis of graft function over 7 years. Nine matched pairs were from adult donors (mean age, 40 years; range, 23-60 years) and six from pediatric donors (mean age, 11 years; range, 4-15 years). All recipients had comparable immunosuppression with cyclosporine A, prednisolone, and azathioprine and comparable numbers of acute rejection, cytomegalovirus reactivation, and antihypertensive therapy. Mean age of pediatric and adult recipients at transplantation was 5 years (range, 1-9 years) and 38 years (range, 25-60 years), respectively. RESULTS: The calculated glomerular filtration rate (GFR) corrected to body surface area was not different in adult and pediatric recipients. Initial absolute GFR was significantly lower in pediatric recipients (27 mL/ min; range, 17-38 mL/min) than in adult recipients (54 mL/min; range, 25-74 mL/min) (P <0.05) and remained lower in the following years. Initially, pediatric donor kidneys transplanted into pediatric recipients showed a lower absolute GFR than those transplanted into adults, however, approaching the GFR in adult recipients later. Adult donor kidneys transplanted into pediatric recipients showed a persistently lower absolute GFR in children compared with those transplanted into adult recipients. CONCLUSIONS: The authors conclude that adult donor kidneys in pediatric recipients decrease GFR in the early stages and lack an increase in GFR with growth of the child.  相似文献   
78.
79.
Summary Neutrophil-derived nucleus- and granule-free cytoplasts, consisting of cytosol enclosed by an intact plasma membrane, were able to destroy 51Cr-labelled ox red blood cells (ORBC) in the presence of phorbol myristate acetate (PMA). The slope of the target cell lysis vs the log of the cytoplast number was similar to that observed with neutrophils as effector cells. Nevertheless, a number of cytoplasts 60–80 times higher than that of neutrophils was required to obtain a common level of cytotoxicity. The ability of cytoplasts and neutrophils to lyse ORBC was completely abolished by catalase and unaffected by superoxide dismutase and mannitol, suggesting the involvement of hydrogen peroxide in the target cell damage. Addition of myeloperoxidase (MPO) to cytoplasts increased lysis. The MPO inhibitor azide significantly reduced the cytolysis by neutrophils, but not the cytolysis by cytoplasts, except when experiments were carried out in the presence of MPO. The results indicate that neutrophil cytosol and plasma membrane represent the basic requirement for the PMA-dependent cytolytic process, whereas MPO behaves as a device to amplify lysis.  相似文献   
80.
Summary β-thromboglobulin (BTG) and fibrinopeptide A (FpA) were studied in 68 non-insulin dependent diabetic patients (NIDD) aged 32–81 with a mean duration of diabetes of 9±0.8 SEM years and 44 healthy controls, comparable for age and sex. Diabetic patients were subdivided into subsets according to the presence of microvascular disease, macrovascular disease or the absence of these lesions. Patients with microangiopathy (micro- and/or macrovascular disease) had higher HbA (p<0.01), higher blood pressure (p<0.05) than both healthy controls and uncomplicated diabetics. Plasma BTG was higher in diabetic patients than in healthy controls (p<0.02), and was higher in complicated than in non-complicated diabetic subjects. Fpa was higher in complicated than in non-complicated diabetes (p<0.05). No differences were observed between the two subsets of complicated patients. In conclusion, we have shown that increased plasma- and platelet-BTG levels are present in non-insulin dependent diabetic subjects, with normal renal function and that plasma BTG is higher in patients with than in those without vascular disease. Fibrinopeptide A, a sensitive marker ofin vivo fibrin formation, was significantly increased in NIDD with vascular complications. This study was supported by the Juvenile Diabetes Foundation Grant N. 184066 and by the National Research Council of Italy,Progetto Finalizzato di Medicina Preventiva e Riabilitativa, Sottoprogetto 4.  相似文献   
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