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11.
Heat stress (HS) is a notable risk factor for female reproductive performance. In particular, impaired oocyte maturation was thought to contribute largely to the HS-induced reproductive dysfunctions. In this study, we confirmed that oocytes undergoing GVBD were much susceptible to HS, and thus compromising subsequent embryonic development. Using N-acetyl-l-cysteine (NAC), we found supplementation of a relatively high dose NAC during in vitro maturation, can protect oocytes from HS-induced complications, and thus rescuing impaired embryonic development. Further analysis indicated that mechanisms responsible for protecting GVBD oocytes from HS by NAC may include: (1) reversing disorganized spindle assembly and inhibited extracellular signal–regulated kinase (ERK) signaling; (2) correcting erroneous H3K27me3 modification and dysregulated expression of imprinted genes; (3) alleviating increased intraoocyte reactive oxygen species accumulation and apoptosis initiation. Our study, focusing on the oocyte meiotic maturation, may provide a safe and promising strategy for protecting reproductive sows under environmental hyperthermal conditions. 相似文献
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Eric E Rasmussen Autumn Shafer Malinda J. Colwell Shawna White Narissra Punyanunt-Carter Rebecca L. Densley 《Journal of Children and Media》2016,10(4):443-461
This study explored the relationship between active mediation, exposure to Daniel Tiger’s Neighborhood, and key indicators of preschoolers’ social and emotional development. One hundred and twenty-seven children aged 2–6 either watched or did not watch 10 episodes of Daniel Tiger’s Neighborhood over a two-week period. Results revealed that preschoolers who watched the program exhibited higher levels of empathy, self-efficacy, and emotion recognition when their regular TV-watching experiences are frequently accompanied by active mediation. This was especially true for younger preschoolers and preschoolers from low-income families. Implications for policy-makers, parents, producers of prosocial programming, and educators are discussed. 相似文献
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《Radiography》2022,28(3):804-810
IntroductionRadiographers are responsible for ensuring safe and effective use of ionising radiation. Through evidence-based practice (EBP), valuable optimisation strategies can be implemented to fulfil these responsibilities. This study aimed to explore radiographers' attitudes, perceptions, and experience of using evidence-based optimisation strategies.MethodsA Grounded Theory approach using in-depth interviews. UK-based radiographers were recruited. Discussions focused on (1) the role of evidence-based optimisation strategies in daily practice, (2) assistance in implementing evidence-based optimisation strategies, and (3) the role of EBP and optimisation strategies in the future. Interviews were transcribed verbatim and analysed using open and axial coding.ResultsParticipants (n = 13) stated that EBP is not frequently used to implement optimisation strategies. Participants relied on the knowledge taught in education settings and their professional skills to optimise in daily practice, alongside departmental protocols. Barriers identified as affecting the implementation of optimisation strategies related to reluctance to change, a lack of support from superiors, and a lack of resources to engage with EBP. Some participants expected the use of optimisation strategies to become unnecessary due to technology advancements.ConclusionThe results indicate that effective operationalisation of EBP is not part of daily practice among radiographers to implement valuable optimisation strategies in daily practice.Implications for practiceThe potential barriers to implementing evidence-based optimisation strategies highlighted in this study suggest that improving access to resources and empowerment of individual radiographers is required to enable radiographers to implement optimisation strategies. 相似文献
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Tarentola annularis is a climbing gecko with a wide distribution in Africa north of the equator. In the present paper, we describe the development of the osteocranium of this lizard, from the first appearance of the cranial elements up to the point of hatching. This is based on a combination of histology and cleared and stained specimens. This is the first comprehensive account of gekkotan pre-hatching skull development based on a comprehensive series of embryos, rather than a few selected stages. Given that Gekkota is now widely regarded as representing the sister group to other squamates, this account helps to fill a significant gap in the literature. Moreover, as many authors have considered features of the gekkotan skull and skeleton to be indicative of paedomorphosis, it is important to know whether this hypothesis is supported by delays in the onset of cranial ossification. In fact, we found the sequence of cranial bone ossification to be broadly comparable to that of other squamates studied to date, with no significant lags in development. 相似文献
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中医药文化是中医药事业发展的根基和灵魂,社会主义文化建设的重要组成。本文考察改革开放40年以来中医药文化发展的演进过程,从“社会矛盾—政策方针—中医药文化发展”的中观视角,构建了中医药文化发展分析模型,发现中医药文化先后经历了资产化发展(1978年-21世纪初)、情景化发展(21世纪初-中国共产党第十八次全国代表大会(中共十八大)前后)、生态化发展(中共十八大至今)三个阶段,每个阶段中医药文化发展的策略、重点和面临的问题具有明显的不同特点。因此,本文提出以社会矛盾为导向,优化政策引导,构建中医药文化生态体系,从个人、社会和国家发展的不同层面采取多元双向发展路径,推进健康中国发展,提升文化自信,打造文化强国。 相似文献
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《Burns : journal of the International Society for Burn Injuries》2022,48(1):201-214
BackgroundThere is an urgent need to empower practitioners to undertake quality improvement (QI) projects in burn services in low-middle income countries (LMICs). We piloted a course aimed to equip nurses working in these environments with the knowledge and skills to undertake such projects.MethodsEight nurses from five burns services across Malawi and Ethiopia took part in this pilot course, which was evaluated using a range of methods, including interviews and focus group discussions.ResultsCourse evaluations reported that interactive activities were successful in supporting participants to devise QI projects. Appropriate online platforms were integral to creating a community of practice and maintaining engagement. Facilitators to a successful QI project were active individuals, supportive leadership, collaboration, effective knowledge sharing and demonstrable advantages of any proposed change. Barriers included: staff attitudes, poor leadership, negative culture towards training, resource limitations, staff rotation and poor access to information to guide practice.ConclusionsThe course demonstrated that by bringing nurses together, through interactive teaching and online forums, a supportive community of practice can be created. Future work will include investigating ways to scale up access to the course so staff can be supported to initiate and lead quality improvement in LMIC burn services. 相似文献