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101.
Schwannomas are neurogenic neoplasms rarely found in the sinonasal tract, where localization to the nasal septum is exceedingly rare (only 11 cases have been described in the western literature). We report the case of a 29-year-old white male with a schwannoma completely filling the left nasal fossa and arising from the bony part of the septum. A computer tomography (CT) scan and a biopsy suggestive of benign schwannoma were obtained before the lesion was removed by a degloving approach. The preoperative diagnosis of nasal septum schwannoma was confirmed. The patient is asymptomatic and without endoscopic evidence of recurrence 7 years after surgery. A review of the literature with particular emphasis on the clinical presentation, histological features, differential diagnosis and therapeutic options for such a rare lesion is included. Received: 11 June 1999 / Accepted: 10 February 2000  相似文献   
102.
The removal of oil from water is a worldwide challenge that must be faced to avoid irreversible marine habitat destruction. A novel fast and simple technique to obtain polydimethylsiloxane (PDMS) membranes is developed using the photopolymerization technique. The high reactivity of the acrylated PDMS formulation toward photo-induced free radical polymerization is assessed via the differential scanning photo-calorimetry (photo-DSC) technique. Two different membranes dense or porous are developed and investigated. Porous membranes, having 100–200 µm as pore size, are obtained using a low-cost environmentally friendly sodium chloride template. Thanks to the hydrophobic/oleophilic intrinsic characteristic of PDMS, the UV-cured membranes can selectively remove dodecane, selected as the target oil, from water. The dodecane sorption capability of both membranes is investigated and compared. Moreover, the membranes can be easily reused since the adsorbed oil can be recovered by simply compressing the membrane. Those PDMS sorbents show high mechanical stability after five adsorption/desorption cycles.  相似文献   
103.
Bombyx mori silk fibroin (SF) is a very versatile biopolymer due to its biocompatibility and exceptional mechanical properties which make possible its use as a functional material in several applications. SF can be modified with a large variety of chemical approaches which endow the material with tailored chemical–physical properties. Here, a systematic investigation of different routes is reported to graft long alkyl chains on SF based on both liquid- and solid-phase, aiming to modulate its hydrophobic behavior. The liquid phase method involves direct activation of SF tyrosine residues via diazo coupling and cycloaddition reactions, generating hydrophobic materials insoluble in any common solvent. The solid phase approach consists of the chemical modification of drop-casted SF films by esterification of hydroxyl groups of serine, threonine, and tyrosine SF residues with acyl chlorides of fatty acids. For the solid-state functionalization, a new class of hydrophobic pendant groups is synthesized, based on triple esters of gallic acid anhydrides, that are reacted with the biopolymer to further enhance its resulting hydrophobic features.  相似文献   
104.
105.
Characterization of cystic tumors of the pancreas: CT accuracy   总被引:4,自引:0,他引:4  
PURPOSE: The purpose of this work was to evaluate the capabilities of CT to accurately characterize cystic tumors of the pancreas. METHOD: Two observers retrospectively evaluated the CT exams of 100 cystic masses of the pancreas, with pathological confirmation. The two observers, blinded about clinical information and the final diagnosis, tried to categorize the lesions according to well established morphologic features. Statistical analysis was performed to measure the agreement between each radiologist and the consensus diagnosis and to evaluate the usefulness of certain CT findings in differentiating one type of cystic pancreatic neoplasm from another. RESULTS: Serous cystadenoma was better diagnosed by CT [Youden misclassification index (Ymi) = 0.72] than mucinous cystic tumor (Ymi = 0.44) and solid pseudopapillary tumor (cystic variant) (Ymi = 0.47). CONCLUSION: As patients with previous history of pancreatitis were excluded from the study, CT findings allowed correct characterization of only 60% of cystic pancreatic masses. Among the remaining 40%, 15-20% of the wrong diagnoses could not be corrected by means of CT, given the patterns shown by the tumors. In 20-25% of the cases, a nonspecific diagnosis of cystic mass was made.  相似文献   
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108.
Background: On the basis of our previous experience, we designed this study to determine the activity and toxicity of outpatient treatment with autologous tumor-infiltrating lymphocytes (TIL) together with intermediate-dose recombinant interleukin-2 (rIL-2) and low-dose recombinant interferon alfa-2a (rIFN-2a), for patients with metastatic melanoma.Methods: Between April 1992 and October 1994, we processed 38 melanoma samples derived from 36 patients with metastases. Proliferative cultures of expanded lymphocytes (TIL) were infused only once into patients with metastatic melanoma. rIL-2 was administered subcutaneously for 1 month, starting on the day of TIL infusion, at an escalating dose of 6–18 × 106 IU/m2/day for the first week and at the maximum-tolerated dose for the subsequent 3 weeks and then, after a 15-day interval, for 1 week/month for 3 months. rIFN-2a was administered subcutaneously at 3 × 106 IU three times each week until progression.Results: Of 38 melanoma samples, 19 (50%) resulted in proliferative cultures and were infused. The median number of expanded lymphocytes was 18 × 109 (range, 1–43 × 109), and the median period of culture was 52 days (range, 45–60). rIL-2 was administered at doses ranging between 6 and 18 × 106 IU/m2/day. Toxicity was mild or moderate, and no life-threatening side effects were encountered. Two of 19 treated patients experienced complete responses of their metastatic sites (soft tissue), 10 had stable disease, and 7 showed progressive disease. The response rate was 11% (95% confidence interval, 2–35%).Conclusions: Outpatient treatment with TIL plus rIL-2 and rIFN-2a is feasible, although, within the context of the small sample size, the activity of the combination was no different from the reported activity of any of the components used alone.  相似文献   
109.
Rolipram is a type IV phosphodiesterase inhibitor endowed with powerful immunomodulatory properties. In this study, we evaluated the effects of this drug on the development of the T-cell-mediated hepatitis inducible in mice by concanavalin A. The results indicated that prophylactic treatment with either 5 or 10 mg/kg rolipram injected intraperitoneally 24 h and 1 h prior to intravenous (i.v.) challenge with 20 mg/kg concanavalin A successfully ameliorated serological and histological signs of liver damage, so that the treated mice showed lower transaminase levels in the plasma and milder mononuclear cell infiltration of the liver as compared to vehicle-treated controls. Moreover, this effect was associated with profound modifications of circulating levels of cytokines released after concanavalin A injection, with the blood levels of interferon-gamma and tumor necrosis factor-alpha being significantly lower and those of interleukin-10 higher than those of the control mice. In particular, the increased blood levels of interleukin-10 might play an important role in the anti-hepatitic effects of rolipram as coadministering this compound with anti-interleukin-10 monoclonal antibody significantly reduced its anti-inflammatory action. These results suggest that rolipram may be useful in the clinical setting for the treatment of cell-mediated immunoinflammatory diseases such as immunoinflammatory hepatitis.  相似文献   
110.
Early MRI findings in Creutzfeldt-Jakob disease   总被引:1,自引:0,他引:1  
We describe the MRI changes preceding the onset of myoclonus in two patients whose post-mortem examination confirmed the diagnosis of Creutzfeldt-Jakob disease (CJD). MRI showed changes in the striatum early in the course of CJD (2–6 months after the onset of apathy, interpreted as depression, and 1–2 months before the onset of further clinical symptoms). Only in one patient did electroencephalography record the typical triphasic sharp-waves, 1 month after MRI.  相似文献   
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