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PURPOSE: To determine the diagnostic performance of liver apparent diffusion coefficient (ADC) measured with conventional diffusion-weighted imaging (CDI) and diffusion tensor imaging (DTI) for the diagnosis of liver fibrosis and inflammation. MATERIALS AND METHODS: Breathhold single-shot echo-planar imaging CDI and DTI with b-values of 0 and 500 second/mm(2) was performed in 31 patients with chronic liver disease and 13 normal volunteers. Liver biopsy was performed in all patients with liver disease with a median delay of two days from MRI. Fibrosis and inflammation were scored on a 5-point scale (0-4). Liver ADCs obtained with CDI and DTI were compared between patients stratified by fibrosis stage and inflammation grade. Receiver operating characteristic (ROC) curve analyses were conducted to evaluate the utility of the ADC measures for prediction of fibrosis and inflammation. RESULTS: Patients with liver fibrosis and inflammation had significantly lower liver ADC than subjects without fibrosis or inflammation with CDI and DTI. For prediction of fibrosis stage > or = 1 and stage > or = 2, area under the ROC curve (AUC) of 0.848 and 0.783, sensitivity of 88.5% to 73.7%, and specificity of 73.3% to 72.7% were obtained, for ADC < or =1.40 x 10(-3) mm(2)/second and < or =1.30 x 10(-3) mm(2)/second (using CDI), respectively. For prediction of inflammation grade > or = 1, AUC of 0.825, sensitivity of 75.0%, and specificity of 78.6% were obtained using ADC < or = 1.30 x 10(-3) mm(2)/second (using CDI). CDI performed better than DTI for diagnosis of fibrosis and inflammation. CONCLUSION: Liver ADC can be used to predict liver fibrosis and inflammation with acceptable sensitivity and specificity.  相似文献   
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Bydon A  Thomas AJ  Seyfried D  Malik G 《Surgical neurology》2002,57(5):325-30; discussion 331-2
BACKGROUND: Controversy about the optimal method of performing a carotid endarterectomy (CEA) exists despite its widespread application and support from various randomized clinical trials. Many surgeons selectively or routinely use electroencephalography (EEG) monitoring as well as shunting when performing this operation. ETHODS: We conducted this retrospective study to assess the maximum carotid clamp time without shunting or EEG monitoring during a CEA without the development of neurological deficits in an already compromised cerebral circulation. RESULTS: Fifteen consecutive patients who underwent CEAs between 1988 and 1999 met our criteria of angiographically documented ipsilateral internal carotid artery (ICA) stenosis with contralateral ICA occlusion. The patient presentations included asymptomatic (14%), transient ischemic attack (TIA) (50%), and stroke (36%). All patients were operated under general anesthesia without shunting and only 4 patients underwent EEG monitoring. On angiography, all 15 patients had ipsilateral ICA stenosis (70-99%) and contralateral occlusion. In 54% of patients, the vertebral arteries (VAs) were both patent, while in 46% of patients only 1 VA was patent. Eighty-five percent of patients had at least 1 patent anterior communicating (Pcomm) artery, while 15% had nonvisualized Pcomm arteries bilaterally. Of the 15 patients, 14 had a patent anterior communicating artery. The mean clamp time of the CCA was 18.5 minutes (range 14-30 minutes). None of the 15 patients had new neurological changes immediately postoperatively or during the 6 weeks of follow-up. CONCLUSION: We propose that shunting may not be necessary during CEA for high-grade stenosis with contralateral ICA occlusion, presumably because of adequate distal small vessel collaterals.  相似文献   
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BACKGROUND: This study was designed to evaluate the impact of an elevated preoperative neutrophil-to-lymphocyte ratio (NLR) on outcome after curative resection for hepatocellular carcinoma (HCC). METHODS: Patients undergoing resection for HCC from January 1994 to May 2007 were identified from the hepatobiliary database. Demographics, laboratory analyses, and histopathology data were analyzed. RESULTS: A total of 96 patients were identified with a median age at diagnosis of 65 (range, 15-85) years. The 1-, 3-, and 5-year overall survival rates were 80%, 58%, and 52%, respectively. Although the presence of microvascular invasion, NLR >or=5, and R1 resection margin were adverse predictors of overall survival, there were no independent predictors identified on multivariate analysis. The 1-, 3-, and 5-year disease-free survival rates were 74%, 63%, and 57%, respectively. Preoperative tumor biopsy, NLR >or= 5, multiple liver tumors, microvascular invasion, and R1 resection margin were all predictors of poorer disease-free survival. Multivariate analysis showed that a NLR >or= 5 and R1 resection margin were independent predictors of poorer disease-free survival. The median disease-free survival of those with a NLR >or= 5 was 8 months compared with 18 months for those with a NLR < 5. CONCLUSION: Preoperative NLR >or= 5 was an adverse predictor of disease-free and overall survival.  相似文献   
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We analysed the morbidity, mortality and outcome of cervical spine injuries in patients over the age of 65 years. This study was a retrospective review of 107 elderly patients admitted to our tertiary referral spinal injuries unit with cervical spine injuries between 1994 and 2002. The data was acquired by analysis of the national spinal unit database, hospital inpatient enquiry system, chart and radiographic review. Mean age was 74 years (range 66–93 years). The male to female ratio was 2.1:1 (M = 72, F = 35). The mean follow-up was 4.4 years (1–9 years) and mean in-hospital stay was 10 days (2–90 days). The mechanism of injury was a fall in 75 and road traffic accident in the remaining 32 patients. The level involved was atlanto-axial in 44 cases, sub-axial in 52 cases and the remaining 11 had no bony injury. Multilevel involvement occurred in 48 patients. C2 dominated the single level injury and most of them were type II odontoid fractures. Four patients had complete neurology, 27 had incomplete neurology, and the remaining 76 had no neurological deficit. Treatment included cervical orthosis in 67 cases, halo immobilization in 25, posterior stabilization in 12 patients and anterior cervical fusion in three patients. The overall complication rate was 18.6% with an associated in-hospital mortality of 11.2%. The complications included loss of reduction due to halo and Minerva loosening, non-union and delayed union among conservatively treated patients, pin site and wound infection, gastrointestinal bleeding and complication due to associated injuries. Among the 28.9% patients with neurological involvement, 37.7% had significant neurological recovery. Outcome was assessed using a cervical spine outcome questionnaire from Johns Hopkins School of Medicine. Sixty-seven patients (70%) completed the form, 20 patients (19%) were deceased at review and 8 patients (7%) were uncontactable. Functional disability was more marked in the patients with neurologically deficit at time of injury. Outcome of the injury was related to increasing age, co-morbidity and the severity of neurological deficit. Injuries of the cervical spine are not infrequent occurrence in the elderly and occur with relatively minor trauma. Neck pain in the elderly patients should be thoroughly evaluated to exclude C2 injuries. Most patients can be managed in an orthosis but unstable injuries require rigid external immobilization or surgical stabilization.  相似文献   
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BACKGROUND: We recently demonstrated the protein expression profiling of Dunning rat tumor cell lines of varying metastatic potential (G (0%), AT-1 ( approximately 20%), and MLL (100%)) using SELDI-TOF-MS. As a parallel effort, we have been pursuing the identification of the protein(s) comprising the individual discriminatory "peaks" and evaluating their utility as potential biomarkers for prostate cancer progression. METHODS: To identify the observed SELDI-TOF-MS m/z (mass/charge) values with discriminatory expression between different sublines, we employed a combination of chemical pre-fractionation, liquid chromatography, gel electrophoresis and tandem mass spectroscopy. Identified proteins were then verified by immuno-assay and Western analysis. RESULTS: A 17.5 K m/z SELDI-TOF-MS peak was found to retain discriminatory value in each of two separate study-sets with an increased expression in the metastatic MLL line. Sequence identification and subsequent immunoassays verified that Histone H2B is the observed 17.5 K m/z SELDI peak. SELDI-based immuno-assay and Western Blotting revealed that Histone H2B is specifically over-expressed in metastatic MLL lines. CONCLUSIONS: SELDI-TOF MS analysis of the Dunning prostate cancer cell lines confirmed the consistent overexpression of a 17.5 K m/z peak in metastatic MLL subline. The 17.5 kDa protein from MLL has been isolated and identified as Histone H2B.  相似文献   
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