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991.
992.
Event-related brain potentials (ERPs) were recorded during a computerized and modified version of the Digit Span Backwards (DB) task from the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III). The modified DB version (ERP-DB task) was divided into two sections of 2, 4, 6 and 8 digits in length (Group 1) and 3, 5 and 7 digits in length (Group 2). Each trial had a study phase and a test phase. For the study phase, a series of digits was presented sequentially and aurally to 20 participants (10 for each group). For the test phase, a second series of digits was also presented sequentially and aurally that either corresponded to the reverse order of the digits in the study phase (correct condition) or had one digit in the sequence replaced by an incorrect digit (incorrect condition). The traditional DB task of the WAIS-III was also administered for comparison purposes. A prolonged positive slow wave (PSW) peaking between 450 and 750 ms was elicited to incorrect condition trials. For each participant, a derived measure was calculated from the ERP differentiation between correct and incorrect conditions. The derived measure was defined as the mean of the t-values obtained from the correct and incorrect waveform comparison, within the temporal interval that encompassed this component. The strongest statistical correlations between the derived measure and the traditional DB test scores were found at the Pz site (Group 1: r=0.79; Group 2: r=0.59). This statistical approach shows that it is possible to adequately relate an individual's performance on a traditional measure of working memory and ERP patterns. Overall, we believe that this kind of ERP approach holds promise as a technique for assessing quantitatively non-communicative patients.  相似文献   
993.
994.
AIM: Peritonectomy procedures with intraperitoneal chemohyperthermia are an effective but costly treatment for peritoneal carcinomatosis (PC). Consequently a proper selection of patients is necessary. We evaluated the benefit of MRI prior to surgery, in the detection of two of the main surgery contraindications: bulky mesenteric tumors and bladder implants. METHODS: Three experts retrospectively reviewed abdominal and pelvic MRI from 19 cases of surgically proved PC (ovary: 7; colorectal: 7; gastric: 2; pseudomyxoma peritonei: 2; appendix: 1). RESULTS: Mesenteric tumors were always identified as hypersignal masses on axial and coronal fat suppression gadolinium-enhanced T1 images (n=3). Three out of five bladder implants were detected. The two cases of bladder implants that were not detected on MRI were missed because the bladder was not filled. The best sequence for the detection of bladder involvement was axial T2-weighted images with bladder filling. CONCLUSIONS: Evaluating the preoperative resectability of PC is crucial for patient management. MRI seems to reliably detect bulky mesenteric tumors and bladder implants on condition the bladder is filled and appropriate sequences are used.  相似文献   
995.
996.
997.
A diagnosis of sarcoidosis should be substantiated by pathological means in order to thoroughly exclude other diseases. The role of real-time endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of sarcoidosis has not been reported. The purpose of the present study is to evaluate the diagnostic yield of EBUS-TBNA in demonstrating the pathological features of sarcoidosis. In total, 65 patients with suspected sarcoidosis, with enlarged hilar or mediastinal lymph nodes on computed tomography, were included in the study. Patients with a suspected or known malignancy or previously established diagnosis of sarcoidosis were excluded. Convex probe endobronchial ultrasonography integrated with a separate working channel was used for EBUS-TBNA. Surgical methods were performed in those in whom no granulomas were detected by EBUS-TBNA. Patients were followed up clinically. EBUS-TBNA was performed on a total of 77 lymph node stations in 65 patients. A final diagnosis of sarcoidosis was made for 61 (93.8%) of the patients. The remaining four patients were diagnosed as having Wegener's granulomatosis (n=1) or indefinite (n=3). In patients with a final diagnosis of sarcoidosis, EBUS-TBNA demonstrated noncaseating epithelioid cell granulomas in 56 (91.8%) of the patients. No complications were reported. Endobronchial ultrasound-guided transbronchial needle aspiration proved to be a safe procedure with a high yield for the diagnoses of sarcoidosis.  相似文献   
998.
SETTING: Tuberculosis (TB) is frequent in human immunodeficiency virus (HIV) infected patients, but its treatment is hampered by adverse events and paradoxical reactions. OBJECTIVE: To examine the impact of HIV infection and other factors on the risk and spectrum of adverse events related to anti-tuberculosis treatment in a prospective cohort study conducted between January 2003 and August 2004. RESULTS: Of 105 patients treated for TB, 30 were HIV-infected. The overall incidence of adverse events was 122.5 +/- 18.5 per 100 patient-years (py) and the incidence of severe adverse events was 45.2 +/- 11.3/100 py. Age >50 years (OR 2.2, 95%CI 1.01-4.8, P = 0.046) and HIV infection (OR 3.9, 95%CI 2.1-7.5, P < 0.001) were independently associated with a higher risk of adverse events. Hepatitis (30.5/100 py) and neuropathy (28.6/100 py) were the most frequent adverse events. Hepatitis C virus infection was associated with hepatitis (OR 4.2, 95%CI 1.2-15.0, P = 0.028) and neuropathy with HIV infection (OR 3.8, 95%CI 1.1-13.7, P = 0.040). CONCLUSION: Adverse reactions to anti-tuberculosis drugs are frequent. HIV infection and age >50 years are factors associated with such reactions, while hepatitis C virus infection is a risk factor for hepatitis.  相似文献   
999.
Within the context of early diagnosis of Alzheimer's disease (AD), there is a growing interest in neuropsychological screening tests. Amongst these tests, we focused on the largely used Memory Impairment Screen (MIS). The objective of the present work was to show that adding a 10-min delayed recall to the MIS, improves the test psychometric characteristics in order to detect dementia in the earliest stages. A prospective study was carried out on a cohort of 270 consecutive elderly ambulatory subjects attending the Broca Hospital Memory Clinic: normal controls ( n  = 67), mild cognitive impairment subjects ( n  = 98) and mildly demented patients [ n  = 105, Mini Mental State Examination (MMSE) = 23 ± 4]. This study consisted in testing the advantage of the 10-min delayed recall entitled MIS-D compared with the MIS. At a cut-off score of 6, the MIS-D revealed satisfying psychometric characteristics with a sensitivity of 81% and a specificity of 91%, whilst the MIS alone indicated a sensitivity of 60% and a specificity of 88% in detecting dementia. In demented patients with MMSE score ≥26, MIS-D properties still remained satisfying (sensitivity: 75%, specificity: 92%). MIS-D is a more relevant screening test than MIS alone at very early stages of dementia.  相似文献   
1000.
This study compared the predictive value of the theory of planned behavior in university students in South Africa (N = 251) and the United States (N = 160) who completed an anonymous self-administered questionnaire. Multiple regression analyses revealed that condom use and intention were significantly predicted by positive condom attitude, subjective norm, self-efficacy, and attending university in South Africa. Significant interactions between country and predictors indicated that subjective norm predicted condom use and intention more strongly in the American sample than in the South African sample; attitude predicted intention more strongly in the American sample than in the South African sample; but self-efficacy predicted intention more strongly in the South African sample than in the American sample. The theory of planned behavior may provide a useful framework for interventions to reduce South African students' risk of HIV/and sexuality transmitted diseases. Such interventions should especially focus on building self-efficacy to use condoms.  相似文献   
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