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81.
OBJECTIVE: The objective of this study is to evaluate the inflammatory response caused by endovascular stents in the treatment of aortic aneurysms. METHODS: Twenty-five patients underwent endovascular stent treatment from March through December 2005. The evolution of mediators (sedimentation velocity, C reactive protein, interleukin-6, interleukin-8, tumor necrosis factor-alpha, intercellular adhesion molecule-1, l-selectin), inflammatory cells (leukocytes, lymphocytes, platelets), serum creatinine and body temperature within preoperative period and in the following postoperative periods--1, 6, 24 and 48 h, 7 days, 1-3 months, was analyzed. In order to achieve statistic significance, Friedman test and Wilcoxon test were used, with index of significance of 5% (p<0.05). RESULTS: Peak values of sedimentation velocity, C reactive protein and interleukin-6 were observed at 7 days (p<0.0001), 48 h (p<0.0001) and 24h (p<0.0001), respectively. Tumor necrosis factor-alpha and interleukin-8 did not show statistically significant variability during the entire follow-up. In terms of intercellular adhesion molecule-1 and l-selectin, their expressive values were found in late phase of follow-up, although without statistical significance. Elevation of leukocytes count occurred in premature phase of follow-up (p<0.0001), while lymphocyte and platelet count occurred in a late phase of follow-up (p<0.0001). Serum levels of creatinine did not show significant variability during follow-up. The period between 24 and 48 h corresponded to major frequency for fever (p<0.0001). CONCLUSION: Individual mediators analysis and inflammatory cells demonstrated variability of their values during postoperative follow-up. This could help in the analysis of the inflammatory response evolution caused by endovascular stent treatment for aortic aneurysms in premature and late phases after implantation of the vascular prosthesis.  相似文献   
82.
Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies.  相似文献   
83.
Levetiracetam (LEV) monotherapy was investigated in 25 patients with advanced Alzheimer's disease (AD) and new-onset epileptic seizures in a prospective open-label study. At a daily dose of 1000–1500 mg, 72% were seizure-free for at least one year; 16% discontinued for untolerability; 8% were unresponsive; 4% were lost to follow-up. These results suggest the need for controlled studies to confirm if LEV can be a first-choice drug in AD.  相似文献   
84.
女性控尿解剖学机制的MRI研究   总被引:1,自引:1,他引:0  
目的探讨女性控尿的解剖学机制在MRI(磁共振成像)的表现和观察方法。方法对20例正常控尿的成年女性进行MRI扫描,采用八通道体部线圈、快束自旋回波(FSE)扫描序列进行扫描,采集静息时盆腔横断面、矢状面和冠状面影像。结果MRI显示,女性的尿道分三层结构,与病理学对照,由内向外依次为黏膜及黏膜下组织、肌肉、外膜组织,但无法区分平滑肌与括约肌;与控尿有关的盆底肌肉也能够清楚显示。结论MRI能够清楚观察到女性控尿的有关解剖结构,是观察女性控尿解剖结构的较理想影像方法。  相似文献   
85.
Abstract Polyethylene (PE) wear is a focal issue in joint replacement, so it is essential to understand how it takes place in vivo. PE wear is a multifactorial process with a complex interaction of variables related to the materials used, the mechanical conditions, operative procedures for implantation, activity of the patient and use of prosthesis. We retrieved 65 PE inserts with the respective femoral and tibial components (50 inserts of total knee prostheses and 15 monocompartmental prostheses) from first revision surgeries. The average age of the patients was 68.3 years; the average time to revision was 41.5 months. Macroscopic observation considered the grade, topography and type of wear. Degradation was also studied with scanning electron microscopy. No direct relationship was found between the level of wear and the survival of total or monocompartmental knee prostheses. The duration of 11 (22%) total prosthetic inserts with grade 2 wear was 42.6 months vs. 51.5 months of 17 (34%) total inserts with grade 1 wear. However, study of the relationship between wear grade and wear topography in total inserts suggested that there was a significant connection. In fact, the 22 (44%) prostheses with central and symmetrical wear never showed wear greater than grade 1. Instead, of the remaining 28 prostheses (56%) without central and symmetric wear, only 3 had grade 0 wear. Finally, considering the relationship between wear grade and type of wear, all 18 inserts (27.7%) with grade 2 or 3 wear had 100% delamination. In conclusion, this study suggests that the correct positioning of the prosthetic components, besides its quality, is an important cause of polyethylene wear.  相似文献   
86.
Senna occidentalis (So) is a weed that grows in pastures along fences and in fields cultivated with cereals such as corn and soybean, and many reports have been showing intoxication with this plant in different animal species. It is also used in many medicinal purposes. The objective of the present study was to better evaluate the toxic effects of prolonged administration of So seeds to rats. Forty male Wistar rats were divided into four groups of 10 animals each, three of them respectively fed rations containing 1%, 2% and 4% So seeds, and the last one (control) fed commercial ration for a period of 2 weeks. Fourteen rats were also used in a pair-feeding (PF) experiment. The rats of the experimental groups showed lethargy, weakness, recumbency, depression and emaciation. Two rats of the 4% group and two of the PF group died during the experiment. Histopathological study showed fiber degenerations in the skeletal (Tibial, pectoral and diaphragm) and cardiac muscles. In the liver parenchyma, was observed vacuolar degeneration and, in the kidney, mild nefrosis in the proximal convoluted tubules. All of these alterations occurred in a dose-dependent fashion. Moderate to severe degeneration and spongiosis in the central nervous system, especially in cerebellum. Electron microscopy revealed mitochondrial lesions in all analyzed tissues.  相似文献   
87.
88.
Background: The practice of laparoscopic cholecystectomy in a community hospital is presented. The morbidity of the procedure is analysed and recommendations for improvement are made. Laparoscopic cholecystectomy was introduced into this 200 bed community hospital in October 1990. All five general surgeons accredited to the hospital agreed to participate in a quality assurance programme to determine the incidence of complications and to make recommendations for improvement. Methods: The records of all 534 patients having laparoscopic cholecystectomy between October 1990 and September 1993 were reviewed, and all complications recorded. Results: Of the 534 cases reviewed in the study 470 were considered uncomplicated and 64 patients experienced a total of 85 postoperative complications. The death of one patient was caused by a pulmonary embolus and another patient experienced a myocardial infarction. Twenty patients has postoperative atelectasis or pneumonia and urinary infection or retention occurred in seven. Complications of laparoscopic cholecystectomy requiring a conversion to open cholecystectomy occurred in eight patients, biliary complications occurred in 18 and 11 patients required re-operation. Conclusions: Three areas of concern were identified. They were the incidence of major biliary injury (0.37% of all cases) and its management, the role of cholangiography. and the incidence and prophylaxis of deep venous thrombosis and pulmonary embolism. Recommendations for improvement in these areas were made.  相似文献   
89.
Permeability of pure lipid bilayers to melatonin   总被引:9,自引:1,他引:8  
Abstract: Melatonin, the chief hormone of the pineal gland, has been reported to interact with a variety of different cells. This ubiquitously acting hormone has been found to interact with protein receptors both at the cell membrane and in the nucleus. Moreover, melatonin was recently shown to be a very potent hydroxyl radical scavenger. The present work focuses on the interaction of melatonin with pure lipid bilayers. It is shown that melatonin can cross multilamellar lipid vesicles, which are used here as model systems for the lipid phase of biological membranes. Thus, the data prove that melatonin can easily pass through the cell membrane and bath every part of the cell, as previously suggested in the literature. Melatonin lipid association constant was calculated based on the change of the hormone fluorescence intensity due to its penetration into the hydrophobic lipid phase. Though melatonin was recently shown to be highly soluble in aqueous media, its lipid association constant is rather high, indicating that the biological action of the hormone is likely to be at the membrane level, either via its interaction with membrane receptors, and/or as a lipoperoxidation radical scavenger.  相似文献   
90.
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