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OBJECTIVE: To evaluate the accuracy of predicting long-term mortality in patients with coronary artery bypass grafting (CABG) by using the European system for cardiac operative risk evaluation (EuroSCORE). METHODS: Medical records of patients with CABG (n=3760) between January 1992 and March 2002 were retrospectively reviewed and their predicted surgical risk was calculated according to the standard (study A) and logistic (study B) EuroSCORE. In study A the patients were divided into six groups: 0-2 (n=610), 3-5 (n=1479), 6-8 (n=1099), 9-11 (n=452), 12-14 (n=103) and >14 (n=17). In study B the patients were divided into seven groups: 0.00-2.00 (n=447), 2.01-5.00 (n=1190), 5.01-10.00 (n=890), 10.01-20.00 (n=686), 20.01-30.00 (n=234), 30.01-60.00 (n=254) and >60.00 (n=59). Long-term survival was obtained by the National Death Index and Kaplan-Meier curves were constructed and compared employing the log-rank test. Multivariate Cox regression analysis was performed in order to control for pre, intra and postoperative factors and adjusted hazard ratios were calculated for standard and logistic EuroSCORE groups. The receiver operating characteristic (ROC) curves were plotted to assess the discrimination ability of the EuroSCORE. RESULTS: In study A there were differences among the six groups in 30-day mortality (0.7%, 1.0%, 3.1%, 4.6%, 13.6% and 23.5%; P<0.001), in major complications (8.5%, 10.4%, 16.2%, 20.4%, 31.1% and 35.3%; P<0.001) as well as in actuarial long-term survival (86.2%, 79.6%, 53.6%, 37.9%, 24.9% and 0% from EuroSCORE 0-2 to >14; P<0.001). In study B there were differences among the seven groups in 30-day mortality (0.9%, 1.1%, 1.2%, 3.6%, 3.4%, 8.7% and 15.3%; P<0.001), major complications (8.5%, 10.1%, 12.1%, 18.4%, 16.2%, 26.0% and 30.5%; P<0.001) as well as in actuarial long-term survival (89.5%, 79.9%, 66.9%, 51.0%, 40.3%, 38.4% and 13.7% from EuroSCORE 0.00-2.00 to >60.00; P<0.001). Multivariate Cox regression analysis confirmed that EuroSCORE (standard or logistic) was a statistically significant predictor for long-term mortality, while the area under the ROC curve was 0.72 for either standard or logistic EuroSCORE. CONCLUSION: The predicted surgical risk in CABG patients as calculated by standard or logistic EuroSCORE is a strong predictor for long-term survival in addition to predicting operative survival for which it was originally designed.  相似文献   
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We developed a technique that allows the routine integration of PET in stereotactic neurosurgery, including radiosurgery. We report our clinical experience with the combined use of metabolic (i.e., PET) and anatomic (i.e., MRI and CT) images for the radiosurgical treatment of brain tumors. We propose a classification describing the relative role of the information provided by PET in this multimodality image-guided approach. METHODS: Between December 1999 and March 2003, 57 patients had stereotactic PET as part of their image acquisition for the planning of gamma knife radiosurgery. Together with stereotactic MRI and CT, stereotactic PET images were acquired on the same day using either (18)F-FDG or (11)C-methionine. PET images were imported in the planning software for the radiosurgery dosimetry, and the target volume was defined using the combined information of PET and MRI or CT. To analyze the specific contribution of the PET findings, we propose a classification that reflects the strategy used to define the target volume. RESULTS: The patients were offered radiosurgery with PET guidance when their tumor was ill-defined and we anticipated some limitation of target definition on MRI alone. This represents 10% of the radiosurgery procedures performed in our center during the same period of time. There were 40 primary brain lesions, 7 metastases, and 10 pituitary adenomas. Abnormal PET uptake was found in 62 of 72 targets (86%), and this information altered significantly the MRI-defined tumor in 43 targets (69%). CONCLUSION: The integration of PET in radiosurgery provides additional information that opens new perspectives for the optimization of the treatment of brain tumors.  相似文献   
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Two middle-aged patients presented with rapidly progressive dementia and ataxia, nonspecific electroencephalography findings, and negative cerebrospinal fluid (CSF) protein 14-3-3. Both patients underwent brain magnetic resonance imaging (MRI) scans that demonstrated abnormalities on diffusion-weighted imaging (DWI) sequences, and both were later confirmed to have Creutzfeldt-Jakob disease. (CJD) by tissue examination. Because a recent position paper from the American Academy of Neurology characterized CSF protein 14-3-3 as a gold standard for clinically diagnosing CJD, the authors reviewed studies of CJD in which DWI-MRI imaging and CSF protein 14-3-3 studies were both performed. Among 19 reported cases of CJD with DWI-MRI lesions, CSF protein 14-3-3 was negative in 6 cases and positive in 2 others. The authors' findings suggest that multifocal cortical and subcortical hyperintensities confined to gray matter regions in DWI-MRI may be a more useful noninvasive diagnostic marker for CJD than CSF protein 14-3-3. These observations provide a compelling rationale for a prospective comparative study.  相似文献   
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The Laser Microprobe Mass Analyzer (LAMMA) is a sensitive instrument for identifying and localizing trace elements in tissue samples. Using LAMMA, we have examined melanin-containing neurons of the substantia nigra in patients with Parkinson's disease (PD) and controls. We found that iron significantly accumulates within neuromelanin granules of patients with PD compared to controls. Increased aluminum was found in the neuromelanin granules of 2 of 3 PD cases but in no controls. The accumulation of iron and aluminum, which are known to promote oxidant stress, may account for the selective degeneration of neuromelanin-containing neurons in PD.  相似文献   
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Elevated iron levels, enhanced oxidative damage, and complex I deficiency have been identified in the substantia nigra of Parkinson's disease patients. To understand the interrelationship of these abnormalities, we analyzed iron levels, ferritin levels, and complex I activity in the substantia nigra of patients with Parkinson's disease. Total iron levels were increased significantly, ferritin levels were unchanged, and complex I activities were decreased significantly in the substantia nigra samples. The failure of ferritin levels to increase with elevated iron concentrations suggests that the amount of reactive iron may increase in the substantia nigra of Parkinson's disease patients. There was no correlation between the iron levels and complex I activity or the iron-ferritin ratio and complex I activity in the substantia nigra samples.  相似文献   
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