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Endoscopic treatment of benign tumors of the nose and paranasal sinuses.   总被引:1,自引:0,他引:1  
OBJECTIVE: The endoscopic approach can be successfully employed for the treatment of benign tumors such as fibroosseus and vascular lesions, pleomorphic adenomas, gliomas, and schwannomas. STUDY DESIGN AND SETTING: Nineteen patients diagnosed with benign tumors of the nasal cavity and paranasal sinuses and treated using an endoscopic approach were retrospectively reviewed. The endoscopic approach was used exclusively in 15 cases and was associated with an external approach in 4 cases (due to an intracranial extension of the tumor in 3 patients and its location at the level of the anterior wall of the frontal sinus in the last case). RESULTS: The resection of the lesions was radical in 18 patients and subtotal in 1 case. The mean follow-up was 27 months and only 1 recurrence (5%) was observed in the juvenile angiofibroma group 20 months postoperatively. CONCLUSION: and significance In selected cases, endoscopic surgery can be considered an effective treatment for the resection of benign tumors involving the sinonasal tract.  相似文献   
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Unregulated or increased expression of epidermal growth factor receptor (EGF-R) is a common event in neoplastic transformation; modulation of such a receptor by physiological agents could be, therefore, of clinical interest. We have studied the binding ability, the availability at cell surface, and the synthesis of EGF-R in the A431 and KB human epidermoid cancer cell lines after treatment with recombinant alpha-interferon (IFN-alpha). After 48 h of treatment, IFN-alpha induces, in both cell lines, growth inhibition and enhances class I major histocompatibility HLA complex expression, which is a common marker of IFN action. [125I]EGF total binding assessed after 48 h of treatment with IFN-alpha shows a dose-dependent upregulation of EGF-R binding capacity. Saturation plots of the binding data show that IFN-alpha treatment does not dramatically alter the affinity of the EGF-R and indicate that IFN-alpha only increases the number of low affinity receptors. We show that this effect is due to a specific increase in the synthesis of the receptor protein, as assessed by immunoprecipitation of [35S]methionine-labeled cell extracts. Electron microscopy analysis has confirmed an increase of EGF-R proteins at cell surface without major changes in the morphology of the cells. Taken together, these results indicate that IFN-alpha consistently induces both the binding capacity and the synthesis of EGF-R in human epidermoid cancer cells and suggest the use of such a mechanism for new anticancer therapies.  相似文献   
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We investigated the effect of long-term i.v. administration of L-carnitine on human muscle fibers using morphometric parameters. We administered 2g/day L-carnitine to patients undergoing hemodialysis for at least 12 months. At the end of this period a marked increase in serum and muscle carnitine levels was observed in all patients, together with hypertrophy and predominance of type 1 fibers. L-carnitine was withheld for 4 months, during which time serum and muscle levels gradually decreased and no changes were observed in muscle fibers. Subsequent addition of L-carnitine to dialysis fluid for another 4 months stabilized lower levels. At the end of this period reduction of diameter of type 1 fibers was observed. Type 2 fibers remained unchanged. Moreover, type 1 fibers remained predominant in all cases. Hence, we suggest that carnitine has a specific trophic effect on type 1 fibers which are characterized by an oxidative metabolism.  相似文献   
5.
The synthesis of 2,4-dione derivatives of 1,5-benzodithiepine, 1,5-benzodiazepine and 1,5-benzothiazepine and the anti-microbial activity in vitro of these derivatives and of analogous of 1,5-benzodioxepine, 1,5-benzoxathiepine and 1,5-benzoxazepine, previously prepared, are reported. Some of these compounds showed a good activity against some Gram positive microorganisms and blastomycetes.  相似文献   
6.
The role of donor and recipient factors in initial renal graft non-function   总被引:1,自引:0,他引:1  
ATN is a deleterious problem in the outcome of kidney transplantation. This complication is usually related to multiple factors including donor parameters, surgical technique, ischemic time, and recipient variables. In order to develop prophylactic measures, out of 430 kidney transplants performed in our Department, a series of 90 consecutive cadaveric renal allografts has been considered in this study. The overall incidence of IGNF was 23/90 (25.5%). Kidneys from MOD revealed a lower rate of IGNF (7/35 = 20%) when compared with organs from SOD (16/55 = 29%, P = NS). No difference was noted when kidneys were removed together with heart and/or liver and/or pancreas. Out of the donor factors, only CID was significant (17 +/- 9 hours in IGNF v 11 +/- 10 hours in patients with IGF, P = less than .05). Analysis of data concerning the fate of paired kidneys revealed two cases of IGNF in both kidneys from the same donor v 14 cases of IGNF in only one of the two paired grafts (P = NS). We conclude that: 1. Donor factors are clearly associated with a minority of IGNF. 2. The introduction of multiorgan procurement programs does not complicate early function. 3. Recipient factors (immunological events and intraoperative fluid management) provides important additive effects on initial graft nonfunction.  相似文献   
7.
BACKGROUND: For the first time, microdialysis was used to investigate in vivo and online the myocardial metabolism during and after cardiac surgery in patients treated with two different methods of myocardial protection. METHODS: Thirty patients underwent standard CABG with one of two different methods of myocardial protection. The patients were randomised to receive either cold blood (COLD group) or warm modified Calafiore cardioplegia (WARM group). Microdialysis probes were implanted into the myocardium of left ventricular apical region of the heart. Cardioplegia was given antegrade only. Microdialysis measurements were performed at time intervals before, during and 24 h after cardiopulmonary bypass and analysed for glucose, lactate, pyruvate and glycerol. RESULTS: Myocardial lactate concentrations were significantly higher in the WARM group compared with that of the COLD group, while serum lactate was comparable. Glycerol was significantly higher at the end of the clamping time in the WARM group. At the same time the glucose-lactate ratio as a marker of nutritional disorder had significantly lower levels in the WARM group. The cumulative CK-MB release over 24 h was significantly higher in those hearts protected with warm blood. CONCLUSIONS: The oxidative stress measured was significantly higher in patients undergoing CABG using modified Calafiore cardioplegia, whereas the cold cardioplegia minimised the effects of aortic clamping. The results indicate that cold cardioplegia offers superior protection of the heart, in terms of more rapid normalisation of myocardial metabolism. In elective myocardial revascularisation, intermittent antegrade warm blood cardioplegia is a comparable safe method of myocardial protection. However, in patients referring to a long clamping time, advantages of cold cardioplegia for myocardial revascularisation may be magnified.  相似文献   
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The increased use of Ultrasonography (US) has led to increased detection of simple hepatic cysts. For symptomatic cysts treatment is necessary. Until some years ago surgery was the only therapy. We have treated a large number of patients with Percutaneous Alcohol Sclerotherapy (PAS) and evaluated retrospectively the efficacy of this approach.Data on 21 patients with symptomatic simple hepatic cysts were reviewed retrospectively. Cysts had a mean diameter of 9 cm (range: 7–15 cm). PAS was always performed under local anesthesia and US guidance. 25% of the volume was replaced with 95% ethanol and then completely aspirated after 20–30 minutes.No complications or deaths occurred. In all patients symptoms disappeared after treatment. In 15 out of 21 cases there was no evidence of residual cyst on US, computed tomography (CT) or magnetic resonance (MRI). In 6 patients with shorter follow-up, cysts showed a mean reduction in diameter of 50%. The mean follow-up was 18 months (range 6–60 months).We conclude that PAS is easy with low risk for the patients and with good long-term results; it should therefore become the procedure of choice for simple hepatic cysts.  相似文献   
10.
Metastasis (the spread of cancer from a primary tumor to secondary organs) is responsible for most cancer deaths. The ability to follow the fate of a population of tumor cells over time in an experimental animal would provide a powerful new way to monitor the metastatic process. Here we describe a magnetic resonance imaging (MRI) technique that permits the tracking of breast cancer cells in a mouse model of brain metastasis at the single-cell level. Cancer cells that were injected into the left ventricle of the mouse heart and then delivered to the brain were detectable on MR images. This allowed the visualization of the initial delivery and distribution of cells, as well as the growth of tumors from a subset of these cells within the whole intact brain volume. The ability to follow the metastatic process from the single-cell stage through metastatic growth, and to quantify and monitor the presence of solitary undivided cells will facilitate progress in understanding the mechanisms of brain metastasis and tumor dormancy, and the development of therapeutics to treat this disease.  相似文献   
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