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31.
Objective: To assess risk factors for mortality in cardiac surgical adult patients as part of a study to develop a European System for Cardiac Operative Risk Evaluation (EuroSCORE). Methods: From September to November 1995, information on risk factors and mortality was collected for 19030 consecutive adult patients undergoing cardiac surgery under cardiopulmonary bypass in 128 surgical centres in eight European states. Data were collected for 68 preoperative and 29 operative risk factors proven or believed to influence hospital mortality. The relationship between risk factors and outcome was assessed by univariate and logistic regression analysis. Results: Mean age (± standard deviation) was 62.5±10.7 (range 17–94 years) and 28% were female. Mean body mass index was 26.3±3.9. The incidence of common risk factors was as follows: hypertension 43.6%, diabetes 16.7%, extracardiac arteriopathy 2.9%, chronic renal failure 3.5%, chronic pulmonary disease 3.9%, previous cardiac surgery 7.3% and impaired left ventricular function 31.4%. Isolated coronary surgery accounted for 63.6% of all procedures, and 29.8% of patients had valve operations. Overall hospital mortality was 4.8%. Coronary surgery mortality was 3.4% In the absence of any identifiable risk factors, mortality was 0.4% for coronary surgery, 1% for mitral valve surgery, 1.1% for aortic valve surgery and 0% for atrial septal defect repair. The following risk factors were associated with increased mortality: age (P=0.001), female gender (P=0.001), serum creatinine (P=0.001), extracardiac arteriopathy (P=0.001), chronic airway disease (P=0.006), severe neurological dysfunction (P=0.001), previous cardiac surgery (P=0.001), recent myocardial infarction (P=0.001), left ventricular ejection fraction (P=0.001), chronic congestive cardiac failure (P=0.001), pulmonary hypertension (P=0.001), active endocarditis (P=0.001), unstable angina (P=0.001), procedure urgency (P=0.001), critical preoperative condition (P=0.001) ventricular septal rupture (P=0.002), non-coronary surgery (P=0.001), thoracic aortic surgery (P=0.001). Conclusion: A number of risk factors contribute to cardiac surgical mortality in Europe. This information can be used to develop a risk stratification system for the prediction of hospital mortality and the assessment of quality of care.  相似文献   
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To confirm recent observations about the relationship between immunosuppression and the recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT), we retrospectively analyzed 70 consecutive HCC patients who underwent LT and received cyclosporine (CsA)-based immunosuppression. CsA trough blood levels, measured with the same technique (fluorescence polarization immunoassay), were analyzed at different time points after transplantation. The exposure to the drug was calculated with the trapezoidal rule in each patient. CsA was associated with steroids in 26 patients and steroids and azathioprine in 44 patients. HCC recurred in 7 patients (10.0%). Different immunosuppressive schedules (CsA and steroids vs. CsA, steroids, and azathioprine) or the cumulative dosage of steroids and azathioprine did not influence HCC recurrence that was associated instead with CsA exposure (278.3 +/- 86.4 ng/mL in recurrent vs. 169.9 +/- 33.3 in tumor-free patients; P < 0.001); CsA exposure above 189.6 ng/mL was related to HCC recurrence at the receiver operating characteristic analysis (ROC). The relationship between CsA exposure; various clinical (sex, age, viral- vs. non-viral-related cirrhosis, preoperative vs. incidental diagnosis of HCC, alpha-fetoprotein [AFP] blood level), pathologic (pathologic tumor staging [pT] stage, presence of Milan criteria), and histologic (grading, presence of microvascular tumor invasion) parameters; and tumor recurrence were assessed. AFP (P = 0.032), microvascular tumor invasion (P = 0.044), and CsA exposure (P < 0.001) influenced recurrence-free survival at the univariate analysis; CsA exposure was the only independent prognostic determinant at multivariate analysis (P < 0.001). High CsA exposure favors tumor recurrence; CsA blood levels should be kept to the effective minimum in HCC patients. In the presence of pathologic and histologic risk factors, specific immunosuppressive protocols should be considered.  相似文献   
33.
Magnetic resonance imaging (MRI) is the current gold standard for the diagnosis of brain tumors. However, despite the development of MRI techniques, the differential diagnosis of central nervous system (CNS) primary pathologies, such as lymphoma and glioblastoma or tumor‐like brain lesions and glioma, is often challenging. MRI can be supported by in vivo magnetic resonance spectroscopy (MRS) to enhance its diagnostic power and multiproject‐multicenter evaluations of classification of brain tumors have shown that an accuracy around 90% can be achieved for most of the pairwise discrimination problems. However, the survival rate for patients affected by gliomas is still low. The High‐Resolution Magic‐Angle‐Spinning Nuclear Magnetic Resonance (HR‐MAS NMR) metabolomics studies may be helpful for the discrimination of gliomas grades and the development of new strategies for clinical intervention. Here, we propose to use T2‐filtered, diffusion‐filtered and conventional water‐presaturated spectra to try to extract as much information as possible, fusing the data gathered by these different NMR experiments and applying a chemometric approach based on Multivariate Curve Resolution (MCR). Biomarkers important for glioma's discrimination were found. In particular, we focused our attention on cystathionine (Cyst) that shows promise as a biomarker for the better prognosis of glioma tumors.  相似文献   
34.
AIM: To evaluate the predictors of 10-year survival of patients with hepatitis C recurrence. METHODS: Data from 358 patients transplanted between 1989 and 2010 in two Italian transplant centers and with evidence of hepatitis C recurrence were analyzed. A χ2, Fisher's exact test and Kruskal Wallis' test were used for categorical and continuous variables, respectively. Survival analysis was performed at 10 years after transplant using the Kaplan-Meier method, and a log-rank test was used to compare groups. A P level less than 0.05 was considered significant for all tests. Multivariate analysis of the predictive role of different variables on 10-year survival was performed by a stepwise Cox logistic regression.RESULTS: The ten-year survival of the entire population was 61.2%. Five groups of patients were identified according to the virological response or lack of a response to antiviral treatment and, among those who were not treated, according to the clinical status(mild hepatitis C recurrence, "too sick to be treated" and patients with comorbidities contraindicating the treatment). While the 10-year survival of treated and untreated patients was not different(59.1% vs 64.7%, P = 0.192), patients with a sustained virological response had a higher 10-year survival rate than both the "non-responders"(84.7% vs 39.8%, P 0.0001) and too sick to be treated(84.7% vs 0%, P 0.0001). Sustained virological responders had a survival rate comparable to patients untreated with mild recurrence(84.7% vs 89.3%). A sustained virological response and young donor age were independent predictors of 10-year survival. CONCLUSION: Sustained virological response significantly increased long-term survival. Awaiting the interferon-free regimen global availability, antiviral treatment might be questionable in selected subjects with mild hepatitis C recurrence.  相似文献   
35.
Summary Accurate volume determination of the encephalic ventricles is of importance in several clinical conditions, including Alzheimer's presenile dementia, schizophrenia, and benign intracranial hypertension. Previous studies have investigated the accuracy with which magnetic resonance imaging (MRI) can be used in clinical practice to evaluate the encephalic ventricles. However, adequate evaluation of pathological conditions depends on a sufficient amount of morphometric data from normal subjects. To begin establishing this data base for normal subjects, we evaluated the MRI scans of 38 subjects found to have no apparent pathology and calculated the ventricular volume in each case by using methods previously developed in our laboratory. The results were then compared with published volumes determined from studies that used either ventricular casts or computerized tomographic scans. The average total ventricular volume for all 38 subjects was 17.4 cm3, while that for males was 16.3 cm3 and that for females was 18.0 cm3. A small but significant correlation was found between age of subject and ventricular volume, with ventricular size increasing with age.
Evaluation du volume des ventricules cérébraux à partir des images obtenues en résonance magnétique nucléaire chez 38 sujets humains
Résumé La détermination exacte du volume des ventricules cérébraux est importante en clinique comme par exemple dans la démence présénile d'Alzheimer, la schizophrénie et l'hypertension intracrânienne bénigne. Des études antérieures ont étudié la fiabilité de la résonance magnétique nucléaire en pratique clinique pour évaluer le volume des ventricules cérébraux. Toutefois une évaluation correcte dans les conditions pathologiques implique une bonne connaissance des données morphométriques du sujet normal. Pour établir ces données sur « le sujet normal », nous avons étudié les coupes obtenues en IRM chez 38 sujets apparemment indemnes de toute pathologie; nous avons calculé le volume ventriculaire dans chaque cas en utilisant des méthodes mises au point auparavant dans notre laboratoire. Les résultats ont été ensuite comparés avec ceux obtenus par d'autres études utilisant soit des moules ventriculaires, soit des coupes tomographiques computérisées. Le volume ventriculaire total moyen chez 38 sujets est de 17,4 cm3, mais il est chez les sujets masculins de 16,3 cm3 et chez les sujets de sexe féminin de 18 cm3. Une corrélation faible mais significative a été trouvée entre l'âge du sujet et le volume ventriculaire, étant entendu que la taille du ventricule augmente avec l'âge.
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AIM: To assess the safety and effectiveness of prophylaxis for venous thromboembolism (VTE) in a large population of patients with hepatocellular carcinoma (HCC) on cirrhosis.METHODS: Two hundred and twenty nine consecutive cirrhotic patients with HCC who underwent hepatic resection were retrospectively evaluated to assess whether there was any difference in the incidence of thrombotic or hemorrhagic complications between those who received and those who did not receive prophylaxis with low-molecular weight...  相似文献   
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This study was carried out to evaluate the rate of recovery and time required for detection of mycobacteria from pulmonary and extrapulmonary human clinical samples, by using a fluorescence-quenching-based oxygen sensor (BACTEC 9000 MB; Becton Dickinson Microbiology Systems, Sparks, Md.). The results were compared with those obtained by microscopy, conventional culture in Lowenstein-Jensen (LJ) medium, and a BACTEC radiometric system (BACTEC 460 TB; Becton Dickinson). Of the 779 clinical samples processed, 364 from pulmonary sites and 415 from extrapulmonary sites, 62 (7.9%) were positive for mycobacterial isolates; of the positive samples, 59 (95.1%) were detected with the fluorescent BACTEC 9000 MB system, 57 (91.9%) were detected with the radiometric system (BACTEC 460 TB), and 43 (69.3%) were detected with LJ conventional culture. The mean times to detection of all mycobacteria with BACTEC 9000 MB and BACTEC 460 TB were similar (10.3 and 10.0 days, respectively). The results obtained indicate that the nonradiometric BACTEC (BACTEC 9000 MB) system is as efficient as Bactec 460 TB and significantly more efficient than LJ for the rapid recovery of mycobacteria from both pulmonary and extrapulmonary clinical specimens. Though the BACTEC 9000 MB system is recommended for respiratory specimens, we demonstrated that it can be successfully used also for recovery of mycobacteria from clinical specimens from various extrapulmonary sites.  相似文献   
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