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131.
Alterations in presynaptic and postsynaptic dopaminergic system and cerebral glucose metabolism in corticobasal degeneration (CBD) were assessed to evaluate the potential usefulness of different imaging methods for CBD. (123)I-FP-CIT/(123)I-beta-CIT SPECT and (123)I-IBZM SPECT as well as (18)F-FDG PET were performed in eight CBD patients. Decreased presynaptic dopamine transporter binding was found in all CBD patients while D2 receptor binding was reduced in only one patient. (18)F-FDG PET displayed a contralateral hypometabolism in cortical and subcortical areas in seven out of eight patients. Our results demonstrate that glucose metabolism and DAT are reduced, while D2 receptors may be frequently preserved in CBD.  相似文献   
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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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Background: A radical forequarter amputation with partial chest wall resection (one to four ribs) has been reported for benign and malignant lesions involving the shoulder and chest wall region. Concerns about reconstruction and postoperative pulmonary function have previously limited more extensive chest wall resections. The current report describes the first case in which a complete unilateral anterior and posterior chest wall resection and pneumonectomy (hemithoracectomy) accompany a forequarter amputation. A novel reconstructive technique used the full circumference of the forearm tissue with an intact ulna as a free osseomyocutaneous flap. Methods: In this case, a 21-year-old patient presented with an extensive recurrent desmoid tumor that involved the shoulder, brachial plexus, subclavian vein, and chest wall from the lateral sternal border to the midportion of the scapula and down to the eighth rib. The operative technique involved removal of the entire right hemithorax from the midline sternum to the transverse process posteriorly, down to the ninth rib inferiorly. Due to the absence of a rigid hemithorax, the uninvolved ipsilateral lung was also removed. The forearm flap was prepared before final separation of the specimen and division of the subclavian vessels. Results: Postoperatively, the patient maintained excellent oxygenation without atelectasis or fever and was extubated on the 15th postoperative day. As expected after pneumonectomy, significant decreases from preoperative to immediate postoperative values were noted for the vital capacity (VC) (from 4.87 L to 1.29 L), forced 1-s expiratory volume (FEV1) (from 3.77 L to 1.02 L), and inspiratory capacity (IC) (3.33 1 to 0.99 1). Rehabilitation included a specially designed external prosthesis to provide cosmesis and prevent scoliosis. By the 15th postoperative week the patient had returned to normal social and physical activities, with a gradual improvement in all respiratory parameters: VC 1.52 L, FEV1 1.29 L, IC 1.04 L. There has been no evidence of tumor recurrence at 1 year. Conclusions: This report provides evidence that a complete hemithoracectomy, pneumonectomy, and forequarter amputation can be safely performed for selective tumors involving the shoulder region with extensive chest wall invasion. Reconstruction may be achieved with an extended forearm osseomyocutaneous free flap with an excellent functional outcome. Presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
139.
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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