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21.
OBJECTIVE: The present study tested the hypothesis that cortical electroencephalographic (EEG) rhythms. change across normal elderly (Nold), mild cognitive impairment (MCI), and Alzheimer's disease (AD) subjects as a function of the global cognitive level. METHODS: Resting eyes-closed EEG data were recorded in 155 MCI, 193 mild AD, and 126 age-matched Nold subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. RESULTS: Occipital delta and alpha 1 sources in parietal, occipital, temporal, and 'limbic' areas had an intermediate magnitude in MCI subjects compared to mild AD and Nold subjects. These five EEG sources presented both linear and nonlinear (linear, exponential, logarithmic, and power) correlations with the global cognitive level (as revealed by mini mental state examination score) across all subjects. CONCLUSIONS: Cortical EEG rhythms change in pathological aging as a function of the global cognitive level. SIGNIFICANCE: The present functional data on large populations support the 'transitional hypothesis' of a shadow zone across normality, pre-clinical stage of dementia (MCI), and AD.  相似文献   
22.
Risk of death from acute pancreatitis   总被引:5,自引:0,他引:5  
Summary Conclusions The analysis of all the data available in 192 patients at 24 h from admission shows that only serum glucose above 250 mg/dL (13.88 mmol/L) and serum creatinine above 2 mg/dL (176.8 μmol/L) are prognostic factors of death (P<0.0001). When, however, pathological chest X-rays are also considered in a subset of 149 patients, these and serum creatinine are prognostic factors of death with odds ratios of 2.9 (95% CL 1.3–6.3) and 9.4 (95% CL 2.2–40.7), respectively (P<0.0001). Background In patients suffering from acute pancreatitis, neither Ranson scores nor Glasgow criteria evaluation at 24 h yield a sufficiently reliable prognosis of the risk of death from the first acute attack. Methods After excluding posttraumatic, postsurgical, and post-ERCP acute pancreatitis, we selected 192 consecutive patients admitted in the first instance to our center for a first attack, distinguishing between patients who died and patients who survived. We used Cox's model to analyze the prognostic weight of variables available within 24 h of admission (sex, age, alcohol intake, smoking habits, 17 biochemical tests, body mass index, chest X-rays, body temperature, and shock status). Results Seventeen (8.8%) patients died; mortality showed a decreasing trend over the period of years considered and was correlated, among other things, with necrotizing type of pancreatitis, idiopathic etiology, and shock status on admission.  相似文献   
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24.
The effect of ethyl benzoate (EB), diisobutyl phthalate (DIBP), dibutyl ether (DBE) and triethoxy(phenyl)silane (EPS) as third components on the propene polymerization with the catalyst systems δ-TiCl3/AlCl(C2H5)2 and δ-TiCl3/Al(C2H5)3 was investigated. The influence of external donors on the isotacticity, catalyst activity and average molecular weight (M v) was tested. If external donors are employed, M v decreases, the insoluble fraction in boiling isooctane increases and the catalyst activity is strongly influenced by the mole ratio external donor/TiCl3. The results indicate that all external donors employed have the same qualitative effect on catalytic active centers.  相似文献   
25.
26.
BACKGROUND: Gastric pull-up is a useful method for reconstruction of the upper digestive tract, with considerable morbidity/mortality, especially in esophageal cancers (EC). OBJECTIVE: To analyze the experience of a multidisciplinary team with a laparoscopic gastric pull-up (LGPU) method, with or without thoracoscopy, in a series of 120 patients with EC. STUDY DESIGN: Retrospective. PATIENTS AND METHODS: From 1992 to 2004, 120 EC [cervical/cervicothoracic (3.0%), middle third (15.0%), and inferior third (82.0%)]. Most were squamous cell carcinomas (47.0%) and adenocarcinomas (34.0%). Stomach was dissected and mobilized exclusively by laparoscopy. Occasionally, laparoscopic approach was extended cranially, until connecting with cervical dissection. In other cases, dissection of thoracic esophagus was accomplished through a thoracoscopic approach. RESULTS: Eighty-one patients (68.0%) had LGPU; 39 (32.0%) needed thoracoscopy. Mortality was 5.9%. Complications were fistula (10.0%) and pneumonia (10.0%). All fistulae closed spontaneously; 89.2% of patients could swallow a normal oral diet. CONCLUSION: Low morbidity/mortality of LGPU for EC compared favorably with conventional techniques.  相似文献   
27.
The accuracy of two-dimensional echocardiography in the detection of intracardiac masses was verified in 334 patients who underwent cardiac catheterization in our laboratory over 21 consecutive months. A complete two-dimensional echocardiographic (2DE) examination was performed a day before catheterization. The presence or absence of a mass was verified at surgery in 77 patients who successively underwent mitral or aortic valve replacement (51), left ventricular aneurysmectomy with or without myocardial revascularization (25), and resection of atrial myxoma (2). In 32 patients 2DE revealed the presence of a mass-left or right atrial thrombi in 12, left atrial myxoma in 2, left ventricular thrombi in 16, and endocardial vegetations in 2. The other 45 patients were free of intracardiac masses on 2DE. Anatomic verification at surgery revealed the presence of an intracardiac mass in 34 patients. In 30 (true positives) of these, 2DE revealed the mass as well, and in 4 (false negatives) the presence of a mass had not been identified by 2DE. In 2 patients (false positives) the predicted mass was not found at surgery. Absence of a mass was correctly predicted by 2DE in 41 patients (true negatives). Thus 2DE detected intracardiac masses with sensitivity of 88.2% and a specificity of 95.3%. We recommend that 2DE be performed in all patients prior to hemodynamic study and/or cardiac surgery to enable safer management of patients with intracardiac masses during cardiac catheterization and/or cardiac surgery.  相似文献   
28.
Pretreament with small, per se ineffective doses of the selective D1 antagonist SCH 23390 inhibited hyperactivity induced by cocaine. On the other hand, the classic neuroleptic haloperidol and the selective D2 antagonist metoclopramide prevented the stimulatory effects of cocaine on locomotion only at hypokinetic doses, while the atypical neuroleptic (–)-sulpiride, a selective D2 antagonist, did not produce significant effects when administered at the hypokinetic dose of 12 mg/kg. Finally, at low doses (–)-sulpiride dose-dependently potentiated the locomotor-stimulating effects of cocaine, an effect that is not shared either with haloperidol or with metoclopramide. These results are discussed in terms of different roles of DA receptor subtypes in the modulation of the stimulant effects of cocaine on locomotion.  相似文献   
29.
The content of dolichol, an isoprenoid present in all biological membranes, was determined in isolated sinusoidal liver cells after treatment of rats for 2 and 4 months with a low dosage of the hepatotoxin thioacetamide. The significant decrease in dolichol observed in hepatocytes after 2 months might be explained by peroxidation of the isoprenoid. At the same time point, retinol was retained, and decreased only after 4 months of treatment. After 4 months of treatment therefore both lipids decreased. In a subfraction of hepatic stellate cells, Ito-1 cells, the main storage site of vitamin A, dolichol decreased significantly only after 4 months. A remarkable difference from hepatocytes is that in Ito-1 cells retinol content significantly decreased after 2 months of treatment. In another subfraction, Ito-2 cells, the content of the two isoprenoids decreased in parallel. This heterogeneous subfraction might represent those transitional hepatic stellate cells that, while losing retinol, are in the process of differentiating into myofibroblasts secreting extracellular matrix components. In Kupffer cells and sinusoidal endothelial cells, impairment of dolichol might be observed later, only after 4 months of treatment, while retinol decreases uniformly over time. Starting after two months of treatment, the decrease of dolichol and the increase of retinol in hepatocytes, at the same time as retinol decreases in hepatic stellate cells, might be taken as an early index of incipient liver injury due to thioacetamide. This hypothesis is discussed with regard to a role of dolichol in the modulation of membrane fluidity for intracellular and intercellular retinol transport.  相似文献   
30.
Modern Morbidity following Pulmonary Resection for Postprimary Tuberculosis   总被引:1,自引:0,他引:1  
n = 8), multidrug resistance or noncompliance to the medical treatment ( n = 11), parenchymal sequelae ( n = 3), suspected cancer ( n = 5), and for the correction of postpneumonectomy bronchopleural fistula and empyema ( n = 1). On admission, eight patients presented with sputum positivity (28.6%). Similar to previous series, tubercular predilection for upper lobes was confirmed (21/28, 75%); accordingly, upper lobectomy through an extrapleural approach was the most common procedure (16/28, 57.1%). Atypical segmental resections or segmentectomies were performed in seven patients (25%), whereas a bilobectomy was necessary in another three patients (10.7%) and a completion pneumonectomy in one (3.6%). Additional procedures were an open-window thoracostomy with transpericardial closure of the main bronchus and a tailored thoracoplasty. No operative mortality was reported. Healing was achieved in 26 patients (93%). Bleeding, either from the chest wall or hilar dissection, was the only reported intraoperative complication. Median blood loss, inclusive of early postoperative collections from chest tubes, reached 1330 ml (range 100–3700 ml). Major postoperative complications included recurrent disease (2/28, 7%) in sputum-positive patients and segmental pulmonary embolism (3.5%). Causes of minor morbidity were air leaks resulting in residual space undergoing spontaneous resolution (18%), wound breakdown (14%), and, fever (11%). This limited series confirms the therapeutic value of the surgical treatment of postprimary tuberculosis, provided that correct indications, adequate pre- and postoperative medical coverage, and meticulous technique are applied.  相似文献   
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