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21.
AIM: To report on the histologic evaluation of renal tumors after intraoperative radiofrequency ablation (RFA) performed immediately before surgical nephrectomy. MATERIALS AND METHODS: Ten patients with renal tumors were studied. All tumors were confirmed to be renal cell carcinoma before radio frequency ablation treatment. All specimens were stained with hematoxylin and eosin and nicotinamide adenine dinucleotide (NADH). RESULTS: Mean tumor size was 29 mm (range 14 to 48 mm). Of the 10 tumors 5 were completely devitalized with a treatment margin ranged from 1 to 20mm. One tumor needed two treatment sessions. No complication related to radiofrequency treatment was recorded. CONCLUSIONS: Our data indicate that RFA can completely destroy renal tumors. However, in our study, complete tumor cell death was obtained only in 50% of cases. More studies are needed to ensure that is technique is an effective and reproducible treatment.  相似文献   
22.
Agenesis of common carotid artery is rare and no report of stenting procedures (carotid artery stenting) for associated stenosis of the internal carotid have been published. We report a case of internal carotid stenosis associated with this anomaly. A 73-year-old male with left internal carotid artery originating from the arch, with significant stenosis, was referred to us. Wallstent was deployed with success. Carotid artery stenting should be reserved to uncomplicated arch anatomy and plaques with low fragmentation risk.  相似文献   
23.
OBJECTIVE: Patients with non-small cell lung cancer (NSCLC) with metastases to ipsilateral mediastinal lymph nodes (N2) are an heterogeneous group of patients as regard to prognosis and treatment. Indication and timing of surgery remain controversial. The present study investigates the prognostic factors, in order to identify homogenous subgroups of patients. METHODS: Histologically proven N2-NSCLC patients, who underwent a complete surgical resection were retrospectively reviewed. Clinical and pathological features were reported and analyzed, and survival study was performed. RESULTS: One hundred eighty-three patients were analyzed. Overall 1.3 and 5 years survival rates were, respectively, 70, 35 and 20%, with a median survival time of 24 months. Univariate analysis showed a significant better prognosis for: incidental N2 respect to clinical N2 (5-years 35.4 vs 17.4%); single level lymph node involvement respect to multiple levels (5-years 23.8 vs 14.7%); metastases to superior mediastinal or aortic nodes respect to lower mediastinal nodes (5-years 32 and 24.3 vs 16.3%); right upper lobe tumors with superior mediastinal nodes and left upper lobe tumors with aortic nodes respect to lower lobes tumors with lower mediastinal nodes (5-years 31.8 and 26.9 vs 15.7%). Skip metastases had not a significant survival advantage respect to continuous lymphatic spread. N2 clinical status, the number of levels involved and the two specific patterns of lymphatic spread resulted significant prognostic factors at multivariate analysis. CONCLUSIONS: Clinical N2 status, number of lymph nodes levels involved and specific patterns of lymphatic spread identify homogenous subgroups of patients that can be proposed for different therapeutic strategies.  相似文献   
24.
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks.  相似文献   
25.
Laparoscopic bile duct injuries. Risk factors, recognition, and repair.   总被引:18,自引:0,他引:18  
Records of 11 patients undergoing biliary reconstruction after laparoscopic cholecystectomy are reviewed. Ductal injuries resulted from failure to define the anatomy of Calot's triangle. Risk factors include scarring, acute cholecystitis, and obesity. Presenting findings included anorexia, ileus, failure to thrive, pain, ascites, and jaundice. All patients required hepaticojejunostomies, which were multiple and above the hepatic bifurcation in four patients. Given the extensive nature of these injuries and the frequent need for intrahepatic anastomosis and early stenosis of repairs by referring physicians, we recommend reconstruction be undertaken by an experienced hepatobiliary surgeon. To avoid injuries, a greater appreciation of risk factors and anatomic distortion and variance and strict adherence to principles of dissection and identification of anatomic structures are suggested. The use of cholangiography and a low threshold for conversion to the open procedure are advised.  相似文献   
26.
27.
Self-efficacy in weight management   总被引:10,自引:0,他引:10  
Self-efficacy is an important mediating mechanism in advancing understanding of the treatment of obesity. This study developed and validated the Weight Efficacy Life-Style Questionnaire (WEL), improving on previous studies by the use of clinical populations, cross-validation of the initial factor analysis, exploration of the best fitting theoretical model of self-efficacy, and examination of change in treatment. The resulting 20-item WEL consists of five situational factors: Negative Emotions, Availability, Social Pressure, Physical Discomfort, and Positive Activities. A hierarchical model was found to provide the best fit to the data. Results from two separate clinical treatment studies (total N = 382) show that the WEL is sensitive to changes in global scores as well as to a subset of the five situational factor scores. Treatment programs may be incomplete if they change only a subset of the situational dimensions of self-efficacy. Theoretical and clinical implications are discussed.  相似文献   
28.
Juxtaoral organs known as organs of Chievitz are intramuscular embryonic structures found close to the angle of the mandible near the insertion of the pterygomandibular raphae. They are considered of neuroepithelial origin with no known function. We describe the first tumor of the organ of Chievitz which presented intraorally in a child. Immunohistochemically, the Chievitz nests showed positive reaction for vimentin, cytokeratins, and epithelial membrane antigen and ultrastructurally demonstrated cytoplasmic processes and intermediate filament bundles. These observations, together with light microscopic features, suggest that the epithelial nests of the organ of Chievitz are meningothelial rather than neuroepithelial. Received December 18, 1996; accepted March 13, 1997.  相似文献   
29.
Five cases of nodular, lymphocyte predominant Hodgkin's disease (nLP HD), in which an association with (n = 3) and transformation to (n = 2) large cell lymphoma (LCL) were found, were studied with monoclonal antibodies against B-, T-, and Reed-Sternberg (R-S) cell-associated antigens and epithelial membrane antigen (EMA) on paraffin sections. Both lymphocytic (L) and histiocytic (H) cells of nLP HD and lymphoma cells of LCL expressed multiple B-cell-associated antigens (detected by LN-1/CDw75, L26, MB2, DBB.42, DBA.44, DND.53, DNA.7 antibodies) but did not react with antibodies against T-cell-associated (MT1, UCHL1/CD45RO) (one exception for CD45RO in LCL) and R-S cell-associated (Leu-M1/CD15, Ber-H2/CD30) antigens. EMA was expressed by L and H cells in all cases and conserved in LCL cells, emphasizing the frequent expression of EMA by the diagnostic cells of nLP HD. An antibody (BNH9) against blood group-related antigens (H and Y oligosaccharide antigens) that does not normally react with lymphoid cells was found to be reactive with few L and H cells in two of five and most LCL cells in four of five cases. The finding might be indicative of abnormal activation of lymphoid cells. The data reinforce current implications that nLP HD is a B-cell malignancy in evolution and that it is not truly representative of Hodgkin's disease in terms of biological and clinical behavior.  相似文献   
30.
The authors report their 4-year (1984-1988) experience with TCE in the treatment of primary sacral benign/malignant and vascular bone tumors, after similar preliminary studies on aneurysmal bone cysts. Eleven patients were treated, for a total of 21 procedures: in 85% of the eight cases of palliative embolization, multiple instrumental approaches were needed for late revascularization, up to four consecutive embolizations in the same patients. Severe complications were observed in 19% of the procedures, due to arterial catheterization and/or instrumental maneuvers, but in none of them was surgery required. Technical results--i.e. devascularization of the mass--were optimal/suboptimal in all cases at the end of multiple procedures in the same patient: in 7/8 patients treated for palliation, however, the treatment was repeated, the late venous DSA angiographic control showing recanalization of the great vessels surrounding the lesion and/or revascularization through collateral channels. The analysis of morphological and clinical results (with reference to pain relief, dimension of the mass, and calcification at CT follow up) showed a complete pain relief in 100% of the patients treated preoperatively for palliation. The dimension of the mass was reduced in 12.5% of the cases treated for palliation, and recalcification was demonstrated on CT in 12.5% of cases. In 25.5% the mass had increased in size and in 62.5% its dimensions were unchanged. Effective pain relief was always obtained in the cases treated preoperatively. Thus, in our experience TCE of expansive lesions of the sacral bone can be considered as an effective therapeutical choice, with special reference to pain relief, for use in all inoperable cases, and as a preoperative treatment to minimize blood loss at surgery. Still, embolization materials are not completely satisfying: many of them are expensive, difficult to use and cannot be trusted to permanently occlude the vessels, which forces to intervene more than once to obtain optimal clinicomorphological results. As for malignant lesions, chemo-embolization with cytostatic substances should be used to improve the efficacy of the method. However, even through such negative judgements can be expressed on TCE, both technical and clinical results have been, in our experience, quite satisfactory, which calls for optimization of the methodology.  相似文献   
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