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Rebecca P. Ang Robert M. Klassen Wan Har Chong Vivien S. Huan Isabella Y.F. Wong Lay See Yeo Lindsey L. Krawchuk 《Journal of adolescence》2009,32(5):1225-1237
We provide further evidence for the two-factor structure of the 9-item Academic Expectations Stress Inventory (AESI) using confirmatory factor analysis on a sample of 289 Canadian adolescents and 310 Singaporean adolescents. Examination of measurement invariance tests the assumption that the model underlying a set of scores is directly comparable across groups. This study also examined the cross-cultural validity of the AESI using multigroup confirmatory factor analysis across both the Canadian and Singaporean adolescent samples. The results suggested cross-cultural invariance of form, factor loadings, and factor variances and covariances of the AESI across both samples. Evidence of AESI's convergent and discriminant validity was also reported. Findings from t-tests revealed that Singaporean adolescents reported a significantly higher level of academic stress arising from self expectations, other expectations, and overall academic stress, compared to Canadian adolescents. Also, a larger cross-cultural effect was associated with academic stress arising from other expectations compared with academic stress arising from self expectations. 相似文献
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Kai-Hang Yiu MBBS Chung-Wah Siu MBBS Chu-Pak Lau MD Kathy L.F. Lee MBBS Hung-Fat Tse MD 《Heart rhythm》2007,4(2):221-223
We report a case of successful transvenous, catheter-based, cavotricuspid isthmus ablation for treatment of atrial flutter using microwave energy. Microwave energy was delivered at 900–930 MHz using 21 W of power. Bidirectional cavotricuspid isthmus conduction block was achieved by microwave ablation without any patient discomfort or complication during the procedure. Our initial experience suggests that transcatheter microwave ablation is feasible for the cure of typical atrial flutter. 相似文献
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Marcus P Kennedy Raymond D Coakley Scott H Donaldson Robert M Aris Kathy Hohneker Joel P Wedd Michael R Knowles Peter H Gilligan James R Yankaskas 《Journal of cystic fibrosis》2007,6(4):267-273
BACKGROUND: The impact of infection with Burkholderia gladioli in cystic fibrosis, other chronic airway diseases and immunosuppressed patients is unknown. METHODS: A six-year retrospective review of all patients with B. gladioli infection was performed in a tertiary referral center with cystic fibrosis and lung transplantation programs. In addition, a targeted survey of all 251 lung transplant recipients was performed. Available B. gladioli isolates were analyzed via pulsed field gel electrophoresis. RESULTS: Thirty-five patients were culture positive for B. gladioli, including 33 CF patients. No bacteremia was identified. Isolates were available in 18 patients and all were genetically distinct. Two-thirds of these isolates were susceptible to usual anti-pseudomonal antibiotics. After acquisition, only 40% of CF patients were chronically infected (> or =2 positive cultures separated by at least 6 months). Chronic infection was associated with resistance to > or =2 antibiotic groups on initial culture and failure of eradication after antibiotic therapy. The impact of acquisition of B. gladioli infection in chronic infection was variable. Three CF patients with chronic infection underwent lung transplantation. One post-transplant patient developed a B. gladioli mediastinal abscess, which was treated successfully. CONCLUSIONS: The majority of patients' culture positive for B. gladioli at our center have CF. B. gladioli infection is often transient and is compatible with satisfactory post-lung transplantation outcomes. 相似文献
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Qualitative and quantitative evaluations of the cellular components of bronchoalveolar washings of calves with experimental parainfluenza-3 virus pneumonitis and control calves were made. Calves were exposed to 10(9) TCID50 of PI-3 by intranasal aerosol exposure and bronchoalveolar cells obtained 7 days after infection by volume-controlled bronchopulmonary lavage. Transient tachypnea and pyrexia occurred in all infected calves, and virus was recoverable at 7 days from nasal swabs and lung tissue. Pulmonary lesions were typical of viral pneumonitis, characterized by patchy alveolitis and bronchiolitis with accumulations of cells and inflammatory debris. The mean total lavage cell yield was elevated in the virus-infected calves, and the percentage of neutrophils was elevated (P less than 0.05). Increased numbers of pulmonary alveolar macrophages (PAM) were also recovered but the difference was not significant. Linear regression equations showed that a decreased proportion of PAM from virus-infected animals were phagocytic. The mean initial phagocytic rates of macrophages from calves with viral pneumonitis were significantly decreased (P less than 0.05) over controls. This difference was concentration dependent and required a phagocytic stimulus in excess of 12.5 X 10(6) beads/ml. Studies of phagocytic kinetics showed that PAM from calves with viral pneumonitis had a lower Vmax than PAM from control calves, but that Km values were comparable. No differences in PAM beta-glucuronidase and acid phosphatase activity were observed. These results indicate depressed phagocytic function in PI-3 virus-inflamed lungs relative to controls. In concert with virus-induced airway lesions, such in vivo depression of PAM phagocytic functions would be expected to depress pulmonary particulate clearance and lung defense mechanisms. 相似文献
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