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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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Birgit T Priest Kenneth M Blumenthal Jaime J Smith Vivien A Warren McHardy M Smith 《Toxicon》2007,49(2):194-201
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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Christine Liddell Gordon Rae Tom R M Brown David Johnston Vivien Coates John Mallett 《The British journal of general practice》2004,54(506):667-672
BACKGROUND: Providing patients with an audiotape of their medical consultation has been a relatively common practice in oncology clinics for some years. However, broader generalisability of the technique has yet to be examined. AIMS: To investigate the efficacy of providing patients with an audiotape of their consultation in a general practice setting. DESIGN OF STUDY: Randomised controlled trial: 95 experimental participants, 85 controls. SETTING: Routine surgeries run by two general practitioners (GPs) in two different health centres. METHOD: All patients attending GP appointments were eligible for inclusion. Patients were followed up by telephone 7-10 days later. RESULTS: More than half (61%) of the patients who received a tape listened to it. Among listeners, 64% rated the tape useful or very useful; 24% noticed information not heard in the consultation. Half of listeners (46%) said that their understanding of the consultation improved after listening to the tape. Half of the listeners (48%) shared the tape with others, of whom 71% found sharing helpful or very helpful. However, 21% of those who shared the information with others found this unhelpful or very unhelpful, suggesting that patients may need to be briefed on the potential risks of sharing. At follow-up a week later, it emerged that being given a tape had no effect on adherence with GPs' advice, nor on anxiety about conditions. CONCLUSION: Providing patients with an audiotape of their GP consultation was positively rated by many patients. Although there were no detectable clinical effects at follow-up, the technique merits further evaluation in general practice. 相似文献
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F Leperchey J N Vivien E Vicaut M Galliot S Deplus P Gervais 《International journal of clinical pharmacology research》1985,5(4):283-286
A positive correlation has been observed clinically at the Centre Edouard Rist, Paris, between the degree of pigmentation and the power of isoniazid acetylation in so-called "caucasians". The investigation was based on a relatively small sample of 153 observations, but sufficient to allow a significant statistical analysis. Comparing the results with data published in the literature, it may be assumed that this relationship between the power of acetylation and pigmentation would be applicable to all human beings. The rabbit, having as in man a bi-modal distribution of the power of acetylation, was used for further research of this correlation in that animal. The results of this research in rabbits may be compared with those in man, but further studies are required in view of the interest of this comparison and of the possible consequences of the relationship of pigmentation and the degree of acetylation of isoniazid in human therapeutics. 相似文献
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Maternal and infant nutrition are problematic in areas of Ethiopia. Health extension workers (HEWs) work in Ethiopia’s primary health care system, increasing potential health service coverage, particularly for women and children, providing an opportunity for health improvement. Their roles include improving maternal and infant nutrition, disease prevention, and health education. Supporting HEWs’ practice with ‘non-clinical’ skills in behavior change and health communication can improve effectiveness. This intervention study adapted and delivered a UK-developed training intervention for Health Extension Workers (HEWs) working with the United Nations World Food Programme in Ethiopia. The intervention included communication and behavioral training adapted with local contextual information. Mixed methods evaluation focused on participants’ reaction to training, knowledge, behavior change, and skills use. Overall, 98 HEWs were trained. The intervention was positively received by HEWs. Pre-post evaluations of communication and behavior change skills found a positive impact on HEW skills, knowledge, and motivation to use skills (all p < 0.001) to change women’s nutritional behavior, also demonstrated in role-play scenarios. The study offered substantial learning about intervention delivery. Appropriate cultural adaptation and careful consideration of assessment of psychological constructs are crucial for future delivery. 相似文献
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Ernest C Borden Laurence H Baker Robert S Bell Vivien Bramwell George D Demetri Burton L Eisenberg Christopher D M Fletcher Jonathan A Fletcher Marc Ladanyi Paul Meltzer Brian O'Sullivan David R Parkinson Peter W T Pisters Scott Saxman Samuel Singer Murali Sundaram Allan T van Oosterom Jaap Verweij Jill Waalen Sharon W Weiss Murray F Brennan 《Clinical cancer research》2003,9(6):1941-1956
Sarcomas--like leukemias, which are also mesodermal malignancies--carry biological significance disproportionate to their clinical frequency. Identification of mutations and translocations associated with these tumors has illuminated aberrant signaling pathways that cause these diseases, determine their behavior, and are therapeutic targets. Activated receptor-associated tyrosine kinase c-kit, mutated in most gastrointestinal stromal tumors, has proven a clinically effective target for enzyme inhibition. A translocation involving a single gene family, consisting of EWS and related genes, has been identified in five different sarcomas, and its chimeric protein products could prove similarly amenable to inhibitors. Resolution of the histopathological complexity is being aided by data from molecular and chromosomal characterization. Improvements in imaging, definition of prognostic factors, and surgical and radiotherapeutic treatment have resulted in improved local control. Continued progress will depend on further adapting the rapidly evolving technologies of genomics and proteomics. It will also depend upon accurate histopathological diagnosis based on validated reagents and consistent methodologies applied to adequate tissue samples derived from patients with complete clinical data. Finally, multicenter, coordinated trials, such as those that occurred with assessment of imatinib mesylate in metastatic gastrointestinal stromal tumors, will assure the most rapid reductions in morbidity and mortality. 相似文献
10.
Michael Crump Dongsheng Tu Lois Shepherd Mark Levine Vivien Bramwell Kathleen Pritchard 《Journal of clinical oncology》2003,21(16):3066-3071
PURPOSE: Cyclophosphamide, epirubicin, and fluorouracil (CEF), compared with classical cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy. has lead to an improvement in relapse-free and overall survival in premenopausal women with node-positive breast cancer. We undertook this analysis to more accurately define the estimate of risk of secondary acute leukemia (sAL) following epirubicin-containing chemotherapy regimens. PATIENTS AND METHODS: We assessed the conditional probability of sAL among 1,545 women who received adjuvant (n = 1,477) or neoadjuvant (n = 68) chemotherapy in four National Cancer Institute of Canada Clinical Trials Group trials from 1990 to 1999. The risks associated with epirubicin-containing regimens (CEF or epirubicin and cyclophosphamide [EC]) and other regimens (doxorubicin and cyclophosphamide [AC] or CMF) were determined. RESULTS: A total of 10 cases of sAL were observed (eight acute myelogeneous leukemia, two acute lymphoblastic leukemia): seven among women treated with CEF, two who had received AC, and one following CMF. Using competing risk statistics, the conditional probability of sAL was 1.7% (95% confidence interval [CI], 0.5 to 3.6) among 539 women treated with CEF chemotherapy at a follow-up of 8 years, 0.4% (95% CI, 0% to 1.3%) among the 678 who received CMF, and 1.3% (95% CI, 0% to 4.7%) among the 231 treated with AC. The conditional probability of death from breast cancer at 8 years for the entire group of women treated with epirubicin-containing regimens in all four trials was approximately 34.9%. CONCLUSION: CEF chemotherapy for breast cancer carries a small increased risk of sAL compared with CMF. These estimates of acute leukemia risk are important in discussing treatment with women, especially patients with a lower risk of death from breast cancer, such as those with node-negative breast cancer. 相似文献