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51.
Objective: Endothelial dysfunction represents a critical early component of organ injury following cardiopulmonary bypass. Recent studies demonstrate that the treatment with atorvastatin is associated with a significant improvement of endothelial function independently of its efficacy on cholesterol levels. Therefore, we investigated the effects of preoperative atorvastatin treatment on endothelium function after coronary surgery. Methods: Forty patients undergoing coronary surgery were randomized to treatment with atorvastatin (20 mg/die; N = 20) or placebo (N = 20) 3 weeks before surgery. Twenty normal patients served as control group. The flow-mediated dilations (FMD) of the brachial artery after both reactive hyperemia (endothelium dependent) and nitroglycerin administration (endothelium independent) were evaluated at baseline, at 48 h, and 5 days postoperatively. Results: At baseline, the endothelium-dependent FMD was significantly attenuated in coronary versus normal patients (normal 10.3 ± 1.8% vs coronary 4.1 ± 1.6%, p < 0.01). At 48 h postoperatively all patients exhibited a reduced FMD compared with baseline values: the endothelium-dependent dilatation showed a drop of 60.1 + 15% in the patients of the placebo group compared with 45.8 + 16.6% (p < 0.05) those in the atorvastatin group. At the univariate analysis, no significant correlation was found between serum levels of either total cholesterol or HDL cholesterol and FMD. The nitroglycerin-induced dilation was not significantly influenced by extracorporeal circulation as well as by atorvastatin treatment. Conclusions: The endothelial dysfunction following cardiopulmonary bypass is improved by the treatment with atorvastatin, by a mechanism unrelated to the drug efficacy of controlling serum cholesterol levels.  相似文献   
52.
Omphalocele is the most common congenital defect of the abdominal wall. Mortality rate is between 20 and 70% and early closure of the abdominal wall, within 10 days of life, is vital to the successful outcome of the surgical treatment. The authors describe the use of two bipedicled flaps of abdominal skin to correct the defect of the midline as soon as the reduction of all viscera has been accomplished.  相似文献   
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A girl with Diamond-Blackfan syndrome and hypopituitarism was suspected of having pituitary haemosiderosis because of the clinical picture and the long history of blood transfusions. On T1-weighted MR images the pituitary exhibited a markedly hypointense anterior lobe (mimicking the empty sella), suggesting iron deposition, while on T2W MRI the low signal of the pituitary was surrounded by the high signal of the CSF. MR may be considered the examination of choice for detecting iron overload in the pituitary. Received: 10 November 1997 Accepted: 21 November 1997  相似文献   
54.
To clarify the therapeutic role of echo-guided percutaneous puncture (EPP) in management of amebic liver abscess, 20 patients (24 abscesses) received metronidazole plus EPP. Fluid was aspirated through Chiba needles under real-time sonographic guidance so as to reduce cavity size to less than 3 cm. Not more than two EPPs were necessary in the majority of cases and no complication followed the procedure. This scheme resulted in a shortening of time of both hospitalization (less than or equal to 20 days) and liver lesion healing as assessed by ultrasound (less than or equal to 4 months). It is concluded that EPP is a valuable and safe therapeutic tool for hepatic amebic abscess.  相似文献   
55.
通过人工合成了人类免疫缺陷性病毒(Humanimmunodeficiencyvirus,HIV)糖蛋白肽GP120对人和无脊椎动物(Mytilusedulis)免疫细胞的抑制作用的研究。人单核细胞和Mytilusedulis免疫细胞分别与GP120保温后,均抑制细胞的吞噬细菌(Psudomonasstretzi)作用。应用计算机显微图像术(Computer-assistedmicroscopy)直  相似文献   
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The improvements in the motor ability in patients with Parkinson's disease due to antiparkinsonian medication is well-known and widely documented. Recent results, based both on kinematic parameters and standard electromyographic (EMG) signal analysis, clearly indicated that the medication reduced, as expected, the clinical signs of Parkinson's disease, but did not restore agonist burst duration modulation with distance in elbow flexion movements. The main aim of the present work is to shed more light on this medication effect using a wavelet analysis approach on multiple EMG signals recorded both on shoulder and elbow muscles in ballistic or rapid movements. The wavelet cross-correlation information allows us to evidence some important quantitative features of the EMG signals due to medication.  相似文献   
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Vitamin E affects cell death in adult rat dentate gyrus   总被引:1,自引:0,他引:1  
We have previously reported the presence of dying cells in the granule cell layer (GCL) of adult rat dentate gyrus (DG), where neurogenesis occurs. In particular, we found that cell death in the GCL increased in vitamin E deficiency and decreased in vitamin E supplementation. These findings were regarded as related to changes in neurogenesis rate, which in turn was influenced by vitamin E availability; a neuroprotective effect of vitamin E on cell death was also proposed. In order to verify this latter hypothesis, we have studied cell death in all layers of DG in vitamin E-deficient and vitamin E-supplemented rats and in control rats at different ages, using TUNEL and nick translation techniques. The phenotype of TUNEL-positive cells was characterized and the existence of dying BrdU-positive cells was investigated. Dying cells with neuronal phenotype were observed throughout the DG in all experimental groups. The number of TUNEL-positive cells decreased from juvenile to adult age. A higher number of TUNEL-positive cells in vitamin E-deficient rats and a lower number in vitamin E-supplemented rats, with respect to age-matched controls, were found; moreover, in these groups, TUNEL-positive cells had a different percentage distribution in the different layers of the DG. Our results confirm the occurrence of cell death in DG, demonstrate that cell death affects neuronal cells and support the hypothesis that the effect of vitamin E on cell death is not related to neurogenesis.  相似文献   
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