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A non-dilatable benign stricture of the esophagus is a problem for the patient and always a challenge for the surgeon. The present study is intended to provide some details of surgical technique and the physiological concept that constitutes the basis for patient selection for short-segment jejunoplasty. In this study, out of 98 patients, 91 had complex stricture of the lower, and seven of the cervical esophagus. The main cause of stenosis in 60 patients (61.2%) was gastroesophageal reflux, in 34 (34.7%) post-corrosive damage, and in three (3.0%) it was other causes. All patients were treated by three methods of jejunoplasty: group I (n=54 patients) short-segment of the jejunum; group II (n=37 pts) Roux-en-Y double tract; and group III (n=7 patients) short jejunal segment on the long vascular pedicle. Intraoperative complications occurred in 17 (17.34%) of the patients. An anastomotic leak occurred only in three (3.29%) in group I and II, and 1/98 patients (1.02%) died from mediastinitis. Follow-up of functional results for up to 36 months (average 18 months) was available in 77/97 (79.3%) hospital survivors. Fifty-seven (74%) patients are satisfied with their ability to take food, postoperative reflux was completely denied by 72 (93.5%) patients. Postvagotomy diarrhea was transient and gradually subsided over the course of the first 6 months.  相似文献   
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Flexible tantalum stents (Strecker) were used as an adjunct to percutaneous transluminal angioplasty (PTA) in the treatment of stenotic arterial or venous limbs of Brescia-Cimino hemodialysis fistulas. The diagnostic procedure was performed using retrograde fistulography. After PTA with unsatisfactory results, stents were placed in 5 patients with significant residual stenoses and poor fistula function. Within the mean follow-up period of 6.4 months (range 3–10 months) all fistulas were functioning. We conclude that Strecker stent is useful in the treatment of stenotic hemodialysis arteriovenous fistulas as an adjunct to PTA.  相似文献   
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OBJECTIVE: Reoperative cardiac surgery after previous coronary artery bypass grafting represents a surgical challenge due to the potential for injury to patent coronary grafts, aorta or right ventricle. Standard preoperative imaging using a coronary angiogram and chest radiograph (CXR) often results in inaccurate assessment of mediastinal anatomy. We aimed to evaluate 3D volume rendered computed tomographic imaging as an adjunct to standard preoperative assessment of patients requiring cardiac surgery in whom coronary artery revascularization had been performed in the past. METHODS: Between January 2003 and January 2004, 33 patients with previous coronary revascularization referred for reoperative cardiac surgery underwent preoperative 3D CT imaging in order to optimize the surgical approach. The mean age in this patient population was 72+/-8 years. The combined evaluation of CXR and conventional angiography offered incomplete insight into pertinent mediastinal topography in 85% of patients (28/33). RESULTS: The correlations for distances of the left internal mammary artery (LIMA) to left anterior descending artery (LAD) graft from the midline and posterior sternum obtained by CT angiography (CTA) and CXR were poor, R=0.56 and 0.49, respectively. The correlation coefficients for distances between the right ventricle and the aorta to the sternum obtained by the same methods were similarly marginal, 0.58 and 0.48, respectively. The correlation coefficients for distances between the LIMA to LAD, circumflex and right coronary artery grafts from the midline obtained by CTA and conventional angiography were 0.54, -0.13 and 0.43, respectively. In seven patients (21%) the surgical strategy was modified based on the location of patent grafts in the mediastinum. The hospital mortality was 17% (5/29). Intraoperative injuries to vital structures were encountered in two patients (7%). No injuries to patent LIMA or the aorta were encountered. CONCLUSIONS: The 3D CT imaging technique is useful in defining the optimal surgical strategy for reoperative cardiac surgery. We found that CTA is superior to CXR and conventional angiography in defining the position of patent grafts and vital structures in relation to the midline and posterior sternum. Preoperative mapping of patent coronary grafts and other vital mediastinal structures reduces the morbidity of the reoperation through modification of surgical approaches.  相似文献   
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Proto-oncogenes, growth factors/receptors, and tumour suppressor genes were analysed in malignant metastatic insulinomas. Normal pancreas showed only a moderate immunoreaction for c-myc proto-oncogene and a strong reaction for insulin. Benign insulinomas were slightly or moderately positive for transforming growth factor a (TGFα), weakly positive for epidermal growth factor receptor (EGF-R), and strongly positive for c-myc and insulin. In malignant insulinomas, besides a strong immunoreaction for c-myc and TGFα, activation of c-K-ras and overexpression of p53 protein were found. Insulin reaction was moderate or strong. Three out of six malignant insulinomas displayed a c-K-ras point mutation at codon 12. All mutations were guanine to cytosine transversion, resulting in amino acid substitution, glycine to arginine. Mutations were present in metastatic insulinomas only. Patients with mutated c-K-ras oncogene had overexpression of p53 protein as well as c-myc and TGFα overexpression. Our results support the view that malignant progression is a consequence of more than one genetic lesion and suggest that activation of myc, TGFα, and ras genesα plays a role in a multistep process of tumour progression, perhaps serving as an initiating event.  相似文献   
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Flexible tantalum stents: Effects in the stenotic canine urethra   总被引:2,自引:0,他引:2  
Purpose Evaluate the effects of flexible tantalum stents (Strecker) implanted into stenotic canine urethras.Methods Eight conditioned, adult, German shepherd dogs, weighing 30–40 kg, were used. Strictures were created surgically in the bulbar urethra just proximal to the os penis. Two months postsurgery, strictures were documented radiographically and then balloon dilated. Following dilatation, a single Strecker stent was placed across the stricture. Stents were 7 mm in expanded diameter and either 2 or 4 cm in length. Retrograde urethrography was performed immediately after stent placement and then biweekly for up to 12 months. Two dogs were sacrificed at 2, 4, 6, and 12 months post-stenting, and necropsy was performed. The urethra was excised, fixed, and examined by scanning electron and light microscopy.Results Clinical success was achieved without complications in all animals. Hyperplasia of the urothelium was noted 4–6 weeks after stent placement and was most pronounced at 4–6 months. Mucosal folds were found between the stent struts. Restenosis occurred at the distal end of the stent in one dog. Histological alterations were noted in the deeper layers of the urethral wall.Conclusion Strecker stents were well tolerated in all animals and seem useful for the treatment of urethral strictures.Presented at CIRSE Annual Meeting and Postgraduate Course, Budapest, June 20–24, 1993  相似文献   
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Age estimation is an inescapable part of every identification process. During growth and development, it is possible to estimate age based on the developmental stages of teeth. The aim of this study was to evaluate three frequently used methods for dental age estimation on a broad sample of Croatian children. The sample comprised 1996 digital, standardized orthopantomograms of children (1121 boys and 875 girls) aged 5 to 16, collected in four major Croatian cities. Age was estimated according to the Demirjian, Willems and Haavikko methods and the accuracy of the estimation was evaluated. The Kappa for intra-examiner agreement was 0.83 for the Haavikko stages and 0.92 for the Demirjian stages. Using the Demirjian method, the average overestimation of age was 0.80 years for boys and 0.84 years for girls. The Willems method overestimated the mean age by 0.41 years in boys and 0.22 years in girls. The Haavikko method underestimated the mean age by 0.60 years in boys and 0.80 years in girls. The Willems method proved to be the most accurate and can be used for dental age estimation among Croatian children. The Demirjian and Haavikko methods showed greater deviation between dental and chronological age and require adaptation when used in the Croatian population.  相似文献   
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