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51.
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
52.
Current transition assessment practices. 总被引:1,自引:0,他引:1
Although researchers have called for a movement away from prediction-related assessments to those which identify specific skill deficits, the extent to which professionals responsible for vocational assessment have shifted their focus is uncertain. The purpose of this investigation was to assess the frequency with which specified prediction-related and skill deficit-related vocational assessment procedures were administered by a sample of secondary-level teachers and employment training specialists. Additionally, the frequency with which these professionals used assessment data to aid in decision making was determined. The results revealed that teachers and employment training personnel used a variety of assessment procedures to make transition decisions. The implications of these findings are discussed. 相似文献
53.
A number of vitamin D3 metabolites inhibit benzodiazepine- and dimethyl sulfoxide-induced differentiation of Friend erythroleukemia cells. The inhibition is dose dependent and occurs at nM concentrations. The order of potency of these compounds is 1,25-dihydroxycholecalciferol greater than 1,25,26-trihydroxycholecalciferol greater than 1,24R,25-trihydroxycholecalciferol greater than 1 alpha-hydroxycholecalciferol greater than 24R,25-dihydroxycholecalciferol greater than 25S,26-dihydroxycholecalciferol. The inhibition is maximal when the vitamin D3 analogs are added together with the inducer, and becomes progressively decreased with delayed addition. These results suggest that the vitamin D3 metabolites may play a regulatory role in erythropoiesis. 相似文献
54.
Peter J. Morgan Lynda M. Williams Gary Davidson Wilfred Lawson Edward Howell 《Journal of neuroendocrinology》1989,1(1):1-4
The functional significance of the pars tuberalis (PT) of the mammalian adenohypophysis has remained an enigma (1, 2). One view of its function is that it acts as an auxiliary gland to support the endocrine role of the pars distalis (PD) (2), as it has been shown to contain immunocytochemically identifiable thyrotrophs and gonadotrophs (1). Many of the cells of the PT are, however, ultrastructurally unique suggesting an independent function for this tissue. Our recent demonstration that the PT of the rat is a major binding site for the ligand iodomelatonin lends further support to this idea (3). We have utilized the highly specific ligand [125 l]melatonin, and have demonstrated that it binds exclusively, with very high affinity, to the PT but not the PD of the adult sheep adenohypophysis. These findings support the conclusion that the PT has a distinct role in relation to melatonin action and seasonal reproduction. 相似文献
55.
56.
Incidence of BK with Tacrolimus Versus Cyclosporine and Impact of Preemptive Immunosuppression Reduction 总被引:8,自引:0,他引:8
Daniel C. Brennan Irfan Agha Daniel L. Bohl Mark A. Schnitzler Karen L. Hardinger Mark Lockwood Stephanie Torrence Rebecca Schuessler Tiffany Roby Monique Gaudreault-Keener Gregory A. Storch 《American journal of transplantation》2005,5(3):582-594
Our purposes were to determine the incidence of BK viruria, viremia or nephropathy with tacrolimus (FK506) versus cyclosporine (CyA) and whether intensive monitoring and discontinuation of mycophenolate (MMF) or azathioprine (AZA), upon detection of BK viremia, could prevent BK nephropathy. We randomized 200 adult renal transplant recipients to FK506 (n = 134) or CyA (n = 66). Urine and blood were collected weekly for 16 weeks and at months 5, 6, 9 and 12 and analyzed for BK by polymerase chain reaction (PCR). By 1 year, 70 patients (35%) developed viruria and 23 (11.5%) viremia; neither were affected independently by FK506, CyA, MMF or AZA. Viruria was highest with FK506-MMF (46%) and lowest with CyA-MMF (13%), p = 0.005. Viruria >/= 9.5 log(10) copies/mL was associated with a 3-fold increased risk of viremia and a 13-fold increased risk of sustained viremia. After reduction of immunosuppression, viremia resolved in 95%, without increased acute rejection, allograft dysfunction or graft loss. No BK nephropathy was observed. Choice of calcineurin inhibitor or adjuvant immunosuppression, independently, did not affect BK viruria or viremia. Viruria was highest with FK506-MMF and lowest with CyA-MMF. Monitoring and preemptive withdrawal of immunosuppression were associated with resolution of viremia and absence of BK nephropathy without acute rejection or graft loss. 相似文献
57.
58.
Charles P. Mouton Rebecca J. Rodabough Susan L. D. Rovi Robert G. Brzyski David A. Katerndahl 《Annals of family medicine》2010,8(3):206-213
PURPOSE The purpose of this study was to examine the psychological effects of physical and verbal abuse in a cohort of older women.METHODS This observational cohort study was conducted at 40 clinical sites nationwide that are part of the Women’s Health Initiative (WHI) Observational Study. We surveyed 93,676 women aged 50 to 79 years using the mental health subscales and the combined mental component summary (MCS) score of the RAND Medical Outcomes Study 36-item instrument.RESULTS At baseline, women reporting exposure to physical abuse only, verbal abuse only, or both physical and verbal abuse had a greater number of depressive symptoms (1.6,1.6, and 3 more symptoms, respectively) and lower MCS scores (4.6, 5.4, and 8.1 lower scores, respectively) than women not reporting abuse. Compared with women who had no exposure to abuse, women had a greater increase in the number of depressive symptoms when they reported a 3-year incident exposure to physical abuse only (0.2; 95% confidence interval [CI], −0.21 to 0.60), verbal abuse only (0.18; 95% CI, 0.11 to 0.24), or both physical and verbal abuse (0.15; 95% CI, −0.05 to 0.36); and they had a decrease in MCS scores when they reported a 3-year incident exposure to physical abuse only (−1.12; 95% CI, −2.45 to 0.12), verbal abuse only (−0.55; 95% CI, −0.75 to −0.34), and both physical and verbal abuse (−0.44; 95% CI, −1.11 to −0.22) even after adjustment for sociodemographic characteristics.CONCLUSION Exposure to abuse in older, functionally independent women is associated with poorer mental health. The persistence of these findings suggests that clinicians need to consider abuse exposure in their older female patients who have depressive symptoms. Clinicians caring for older women should identify women at risk for physical and verbal abuse and intervene appropriately. 相似文献
59.
Diseases like rotavirus afflict both upper- and lower-income countries, but most serious illnesses and deaths occur among the latter. It is a vital public health issue that vaccines for these types of global diseases can recover research and development (R&D) costs from high-priced markets quickly so that manufacturers can offer affordable prices to lower-income nations. Cost recovery depends on how high R&D costs are, and this study attempts to replace high, unverified estimates with lower, more verifiable estimates for two new vaccines, RotaTeq (Merck) and Rotarix (GlaxoSmithKline or GSK), based on detailed searches of public information and follow-up interviews with senior informants. We also offer a new perspective on “cost of capital” as a claim for recovery from public bodies. Our estimates suggest that companies can recover all fixed costs quickly from affluent markets and thus can offer these vaccines to lower-income countries at prices they can afford. Better vaccines are a shared project between companies and public health agencies; greater transparency and consistency in reporting of R&D costs is needed so that fair prices can be established. 相似文献