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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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The tarantula venom peptides ProTx-I and ProTx-II inhibit voltage-gated sodium channels by shifting their voltage dependence of activation to a more positive potential, thus acting by a mechanism similar to that of potassium channel gating modifiers such as hanatoxin and VSTX1. ProTx-I and ProTx-II inhibit all sodium channel (Nav1) subtypes tested with similar potency and represent the first potent peptidyl inhibitors of TTX-resistant sodium channels. Like gating modifiers of potassium channels, ProTx-I and ProTx-II conform to the inhibitory cystine knot motif, and ProTx-II was demonstrated to bind to sodium channels in the closed state. Both toxins have been synthesized chemically, and ProTx-II, produced by recombinant means, has been used to map the interaction surface of the peptide with the Nav1.5 channel. In comparison, beta-scorpion toxins activate sodium channels by shifting the voltage dependence of activation to more negative potentials, and together these peptides represent valuable tools for exploring the gating mechanism of sodium channels.  相似文献   
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A study to explore the role of a community oncology nurse specialist   总被引:1,自引:0,他引:1  
Cancer patients are increasingly being cared for in the community. However, the role of the community oncology nurse specialist (CONS) remains a rare appointment in the United Kingdom. There is little research evidence to substantiate the view that this is a worthwhile and effective role. This study aimed to explore the role of one CONS using a qualitative case study approach. The sample consisted of the CONS, seven patients, no relatives and five community nurses. Semi-structured interviews were used to elicit the view of these participants. In addition, documents containing details of the CONS's work to date were reviewed. A number of the CONS's role components were identified by the different respondent groups. Five themes were identified within the data collected: functions of the CONS, communication between the CONS and other health care professionals, structural and organizational factors, characteristics of the service and benefits to patients and their families. Furthermore, all respondent groups were positive about the service offered by the CONS, and felt that the role was valuable. Some negative features were identified and these were concerned with organizational aspects of the service. The findings suggest the need for further research and evaluation in this area.  相似文献   
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