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Embryoid body (EB) formation forms an important step in embryonic stem cell differentiation invivo. In murine embryonic stem cell (mESC) cultures EB formation is inhibited by the inclusion of leukaemic inhibitory factor (LIF) in the medium. Assembly of mESCs into aggregates by positive dielectrophoresis (DEP) in high field regions between interdigitated oppositely castellated electrodes was found to initiate EB formation. Embryoid body formation in aggregates formed with DEP occurred at a more rapid rate-in fact faster compared to conventional methods-in medium without LIF. However, EB formation also occurred in medium in which LIF was present when the cells were aggregated with DEP. The optimum characteristic size for the electrodes for EB formation with DEP was found to be 75-100 microns; aggregates smaller than this tended to merge, whilst aggregates larger than this tended to split to form multiple EBs. Experiments with ESCs in which green fluorescent protein (GFP) production was targeted to the mesodermal gene brachyury indicated that differentiation within embryoid bodies of this size may preferentially occur along the mesoderm lineage. As hematopoietic lineages during normal development derive from mesoderm, the finding points to a possible application of DEP formed EBs in the production of blood-based products from ESCs. 相似文献
85.
Michael J. Shoemaker Amy B. Curtis Eric Vangsnes Michael G. Dickinson 《Cardiopulmonary Physical Therapy Journal》2012,23(3):5-15
Purpose
The purpose of the present review was to use existing, published data to provide an estimate of the amount of change in six-minute walk test distance (Δ6MWT) that represents a clinically meaningful change in individuals with chronic heart failure (CHF).Methods
The present review included two separate literature searches of the CINAHL and Medline databases for articles that: (1) reported the intraclass correlation coefficient (ICC) of the 6MWT in individuals with CHF, and (2) used the 6MWT along with either aerobic capacity or health-related quality of life (HRQL) as study endpoints in randomized controlled trials (RCTs) of exercise-based intervention for individuals with CHF. The ICCs were used to calculate the minimum detectable difference (MDD) at the 95% confidence interval for each included study. The Δ6MWT associated with aerobic capacity and HRQL within-group effect sizes for the intervention and control groups in each included RCT was analyzed using receiver operating characteristic (ROC) curves.Results
Thirteen articles reported the ICC for the 6MWT. The mean (standard deviation) MDD calculated based on these data was 43.1(16.8) m. Eighteen RCTs measured the 6MWT and either aerobic capacity and/or HRQL. A Δ6MWT of 40–45 m was associated with at least moderate aerobic capacity and HRQL effect sizes in the intervention groups. The Δ6MWT thresholds that discriminated between intervention and control groups using ROC curves revealed the following sensitivity/specificity for the respective thresholds: 19 m, 94.4/83.3%, 32 m, 83.3/94.4%, and 48 m 44.4/100% (AUC = .935, p = .009, CI95% .855, 1.015).Conclusions
A Δ6MWT of approximately 45 m appears to exceed measurement error and be associated with significant changes in either aerobic capacity and/or HRQL.Key Words: heart failure, six-minute walk test, clinically meaningful change, minimum detectable difference 相似文献86.
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Doulas, women who primarily provide social support during childbirth, have been associated with a number of positive health outcomes. Because the primary model of practice for doulas is a fee-for-service model in which families privately hire a doula, many expectant women who could benefit from doula support are unable to access the service. The Doulas Care program, located in Ann Arbor, Michigan, represents one model in which doulas provide services without charge. As a result of their extended role in the community, doulas who work with the Doulas Care program have unique educational needs. Through the use of focus groups with the program's volunteer doulas, educational needs related to overcoming barriers to being a doula working in the community were identified. Recommendations for education and training are made to improve the support doulas offer as community health outreach workers. 相似文献
88.
Romano AM 《The Journal of perinatal education》2006,15(3):58-60
In this column, the author presents summaries of four research studies that further support the benefits of normal birth. The topics of the studies address cord clamping of term infants, the association of multiple cesareans and placental abnormalities, induction of labor at 41 weeks, and the World Health Organization's recently released pediatric growth charts. 相似文献
89.
OBJECTIVES: To describe the characteristics and repertoires of community practitioners serving families involved in child physical abuse that may inform training and treatment dissemination efforts. The aims are to: (a) describe the background characteristics of these clinicians; (b) document their most common intervention techniques; (c) examine clinicians' attitudes toward manualized treatment; and (d) understand the organizational climate of community agencies. METHOD: Practitioners from nine different agencies who have worked with cases in which there was child physical abuse (n=77) completed focus group discussions and three self-report questionnaires. Qualitative and quantitative analyses were conducted in tandem. RESULTS: Practitioners reported that they most often focused on family issues and employed family therapy techniques. Although treatment manuals were important, it was difficult to determine how practitioners used or would use these materials with families. An almost equal number of concerns and benefits were raised regarding using manuals in treatment. There was moderate agreement in how practitioners perceived their work environments. Age and attainment of a graduate degree were positively related to greater caring and job satisfaction, respectively, while length of time at a given agency was positively related to greater reports of emotional exhaustion on a measure of organizational climate. CONCLUSIONS: Given the promising benefits of evidence-based treatments for child abuse, it is important that researchers begin to form partnerships with community agencies that will lead to the dissemination and evaluation of effective treatment strategies. 相似文献
90.
Pam Maras Amy Moon Taveeshi Gupta Nicole Gridley 《Emotional and Behavioural Difficulties》2013,18(4):362-380
The relationship between materialism and social-emotional behavioural difficulties (SEBDs) was assessed by comparing a sample of adolescents receiving in-school behavioural support with adolescents not receiving any support. All participants completed the Youth Materialism Scale and the Strengths and Difficulties Questionnaire. Binary logistic regression indicated that adolescents who reported higher levels of materialism were more likely to be classified into a group considered ‘at-risk’ for developing conduct and peer problems. Hierarchical logistic regression assessed the moderation of behavioural support and indicated that adolescents in receipt of behavioural support who reported higher levels of materialism were at a greater risk of hyperactivity in comparison to those who receive support but reported lower levels of materialism. For adolescents not receiving behavioural support, less materialistic attitudes placed them at a greater risk of hyperactivity. These findings highlight the importance of distinguishing between different SEBD typologies and the potential effects of materialism during adolescence. 相似文献