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21.
Cytochrome P4502E1 (CYP2E1) plays an important role in ROS production thus favouring accelerated membrane lipid peroxidation. This isoform is strongly expressed in the liver but it can be also found in lymphocytes. As such, lymphocyte may provide a non-invasive accessible pool for screening CYP2E1 expression in man. We have, therefore, analysed CYP2E1 expression and activity in lymphocyte microsomes from 12 healthy controls, 11 type 1 and 12 type 2 diabetic subjects by using Western blot and enzymatic activities. Immunoblotting did not show difference among CYP2E1 protein bands in controls, type 1 and type 2 diabetics. To assess CYP2E1 activity we used the 7-ethoxy-4-trifluoromethylcoumarin (7-EFC), as a fluorescent substrate. The rate of deethylation of 7-EFC from controls did not differ from type 1 and type 2 diabetic subjects. The lack of any difference in CYP2E1 activity also was confirmed by the NADPH-dependent microsomal lipid peroxidation CCL4-induced assay showing similar peroxidation rates among controls and diabetic subjects. The results show that CYP2E1 expression/activity in lymphocytes is not enhanced in diabetes.  相似文献   
22.
This paper presents the results of an experimental investigation which was carried out with the purpose of assessing the performance-related properties of an emulsion-based cold-recycled mixture to be employed as a sustainable solution for the surface finishing of unpaved rural roads. This mixture contained significant quantities of recycled components (reclaimed asphalt and mineral sludge), and its composition was fine-tuned by following an innovative mix design procedure. Properties of these mixtures were studied by means of laboratory tests which considered key parameters, such as flowability, indirect tensile stiffness modulus, indirect tensile strength, moisture susceptibility and resistance to permanent deformation. It was found that, by means of the proposed mix design procedure, optimal dosages of the recycled components can be identified, thereby ensuring the achievement of the desired properties in terms of high workability and adequate stiffness and strength.  相似文献   
23.
OBJECTIVE: We reviewed our experience in the surgical management of 80 patients with colorectal pulmonary metastases and investigated factors affecting survival. MATERIAL AND METHODS: From January 1980 to December 2000, 80 patients, 43 women and 37 men with median age 63 years (range 38-79 years) underwent 98 open surgical procedure (96 muscle-sparing thoracotomy, one clamshell and one median sternotomy) for pulmonary metastases from colorectal cancer (three pneumonectomy, 17 lobectomy, seven lobectomy plus wedge resection, six segmentectomy, three segmentectomy plus wedge resection and 62 wedge resection). Pulmonary metastases were identified at a median interval of 37.5 months (range 0-167) from primary colorectal resection. Second and third resections for recurrent metastases were done in seven and in four patients, respectively. RESULTS: Operative mortality rate was 2%. Overall, 5-year survival was 41.1%. Five-year survival was 43.6% for patients submitted to single metastasectomy and 34% for those submitted to multiple ones. Five-year survival was 55% for patients with disease-free interval (DFI) of 36 months or more, 38% for those with DFI of 0-11 months and 22.6% for those with DFI of 12-35 months (P=0.04). Five-year survival was 58.2% for patients with normal preoperative carcino-embryonic antigen (CEA) levels and 0% for those with pathologic ones (P=0.0001). Patients submitted to second-stage operation for recurrent local disease had 5-year survival rate of 50 vs. 41.1% of those submitted to single resection (P=0.326). CONCLUSIONS: Pulmonary resection for metastases from colorectal cancer may help survival in selected patients. Single metastasis, DFI>36 months, normal preoperative CEA levels are important prognostic factors. When feasible, re-operation is a safe procedure with satisfactory long-term results.  相似文献   
24.
Adrenal epithelioid angiosarcoma is an extremely rare tumor. Even if such tumors are very aggressive, a long survival may occasionally be observed after an adrenal ectomy. A 70-year-old woman suffering from persistent right flank pain showed a 5-cm right adrenal mass plus a 2-cm liver mass at the radiologic workup, and both were suspected of being malignant. No adrenal hypersecretion was demonstrated. During an explorative median laparotomy the right adrenal gland with the whole periadrenal tissue and locoregional lymph nodes was removed. A histological examination revealed an adrenal angiosarcoma. The resection margin was tumor-free with no lymph node infiltration. The liver mass turned out to be a cistobiliary adenoma. Since no distant metastases were observed, no adjuvant chemotherapy was performed. After an 18-month follow-up the patient is still well with no sign of a relapse. When this rare adrenal tumor is encountered and curative treatment is attempted initially extensive surgical procedures are essential. Received: April 16, 2001 / Accepted: November 20, 2001  相似文献   
25.

Background  

While laparoscopic Roux-en-Y gastric bypass is one of the most commonly performed procedures for morbid obesity in the USA, robotic application has been viewed as a valid option. However, the technique is not firmly established with single robotic docking. The objective of this video is to demonstrate the technical details of performing a standardized monoquadrant robotic Roux-en-Y gastric bypass (RRYGB).  相似文献   
26.
Objective: Pulmonary resections after pneumonectomy due to metastases or metachronous non-small cell lung cancer (NSCLC) are rare because of the high potential risk of the second procedure and uncertain long-term results. On the basis of our series (largest in Europe) we tried to assess the long-term survival of patients treated in stage IV NSCLC. Methods: Retrospective analysis was carried out on 18 patients treated at our department by pneumonectomy followed by additional resection in the years 1981-2002 (15 males and 3 females, 44-69 years, mean 57). Eleven pneumonectomies were performed on the right side and seven on the left. Twelve squamous cell carcinomas and six adenocarcinomas were diagnosed. All patients were staged postoperatively as IIB-IIIA (four were N2). Their WHO status ranged between 0 and 1. The second surgical procedure (16 wedge resections, 2 chest wall resections) was performed 4-106 months later (mean 26). The patients staged N2 were radiated postoperatively. Results: There were no early postoperative deaths. The morbidity rate after second surgery was comparable to that observed after ordinary wedge resection. Histology of the lesions removed during the second operation was the same as after pneumonectomy in all patients. The pulmonary function tests (PFT) results worsened significantly but still reached 56-63% of the predicted values. Sixteen resected tumors of the remaining lung were staged T1 (<3cm), 2 - T3 (<3cm but infiltration of the parietal pleura on an area of 2-4cm(2)). Three patients revealed N2 disease (they were all N0 after pneumonectomy). All patients were considered M1 after second surgery. WHO status after the second procedure remained the same in 8 patients (44%) and worsened in 10 patients (56%). The survival rates were as follows: 11 patients survived 2 years (61%) while 8 patients survived 5 years (44%). The majority of patients died due to lung cancer (70%) but all the rest (30%) due to circulatory or respiratory insufficiency. There was a significant difference (p<0.05) in 5-year survival for N0-N1 vs N2 status (63% vs 14% - 1 patient) and also regarding the time interval between surgeries: less than 12 months vs more than 12 months (0% vs 63%). Conclusions: Pulmonary resections performed after pneumonectomy due to NSCLC are rare procedures but with an acceptable perioperative risk. The second procedure should be limited to wedge resection. The prognosis is poor for patients with N2 status and for those treated by second surgery earlier than 12 months after the first procedure.  相似文献   
27.
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   
28.
29.
Recently, the posterior cruciate ligament (PCL) has become an increasingly popular subject of orthopaedic research and debate. In the past several years, anatomic and biomechanical studies have provided invaluable information concerning the structure and function of the PCL. However, many aspects of PCL injury are still not fully understood. Diagnosis of the injury is often missed because of subtlety of symptoms and clinical findings, and current management strategies of PCL injury have experienced relatively poor clinical outcomes. Controversy exists concerning the most appropriate treatment, especially in cases of isolated PCL injury. The purpose of this review is to present a complete overview of the current knowledge regarding the basic science and clinical aspects of PCL injuries, with a specific focus on the athletic population.  相似文献   
30.
PURPOSE: To evaluate the incidence of bronchial carcinoid tumor (BCT) in population affected by various lung tumors, retrospectively reviewed between 1986-2001, and to emphasize the radiographic patterns if they are characteristic. MATERIALS AND METHODS: In the above mentioned period, chest x-ray and CT were performed in 1110 patients, both male and female, affected by lung neoplasms. RESULTS: 20 patients were affected by BCT (16 males, and 13 females), aged between 26 and 75 years (mean age 57.5), with histopathologic diagnosis of typical (9 cases, 31%) and atypical (20 cases, 69%) bronchial carcinoid tumors. Localized right lung lesion were as follows: 7 cases in superior, 9 in middle and 4 in inferior lobes; in the left lung, 5 cases in superior, and 4 in inferior lobes. Size of the lesions was as average 2.4 cm in diameter (with a range of 0.5-12 cm). On x-ray and CT images, BCT appeared as a well marginated nodule, of which 9 were peripheral and 20 central. DISCUSSION AND CONCLUSION: BCT are classified as neuroendocrine carcinomas,and are divided in typical and atypical forms, with variable grade of malignancy. Central neoplasms are symptomatic due to bronchial obstruction (i.e., pneumonia, atelectasis, bronchiectasis, emphysema and/or lung abscess); if airway obstruction is partial, then cough, wheezing and recurrent pulmonary infections occur. Peripheral tumors are generally asymptomatic and they are discovered occasionally, when chest x-ray is made for other reasons. Radiographic features are similar in typical and atypical BCT. In central tumors a rounded well circumscribed hilar mass is noted, with lobulated or bumpy margins. Central cavitation is not referred to. Peripheral BCT appear as a solitary nodule, inferioer then 3 cm in size, marginated, surrounded by normal pulmonary tissue. Signs and symptoms of BCT are evasive and vague. No current clinical or laboratory procedures are useful in confirming the diagnosis; particularly, no imaging modalities are able to differentiate between BCT and other pulmonary tumors. For this reason, a clinical radiologic endoscopic and histopathologic approach is necessary. CT is more sensiticve then conventional radiography, especially in detecting small lesions, calcification and enlarged lymph nodes. MRI may be useful in those patients, who cannot tolerate IV contrast media. Scintigraphy may be employed in discovering relapses and long standing metastases.  相似文献   
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