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61.
《河西学院学报》2017,(5):65-71
PTEN(Phosphatase and tensin homologue deleted on chromosome 10)是10号染色体缺失,编码与张力蛋白和辅助蛋白同源磷酸酶的抑癌基因.自1997年被正式发现起,越来越多的研究者对其蛋白、生物学活性、参与信号转导途径、药物靶点等相关方面做了极为深入和广泛的研究.研究显示,PTEN可通过多种信号转导通路,广泛参与人类肿瘤细胞的增殖、恶变、趋化、粘附、血管生成、凋亡、耐药、衰老、肌肉收缩、DNA损伤应答等过程,从而在人类肿瘤的治疗中发挥至关重要的作用,成为肿瘤生物学发展中最为重要的分子之一.迄今为止,涉及PTEN功能的相关临床试验已在肿瘤治疗中取得突破性进展,包括在白血病中的应用.但是国内外对于PTEN与白血病发生、进展、治疗的相关性并无针对性的、较为完善的归纳与总结.本综述结合近年来较为前沿的论点对PTEN与白血病发生、发展与治疗相关进展进行阐述,为进一步的科研提供新的思路与展望. 相似文献
62.
Jered Borup 《Journal of Research on Technology in Education》2016,48(2):67-83
A growing number of adolescents are taking all or most of their courses online. This places a greater responsibility on parents to support and facilitate their students' learning. This case study used teacher surveys and interviews to better understand how teachers perceived and supported parents' attempts to support their online students at a single online charter school. The results indicated that teachers observed multiple ways in which parents supported their students by (a) organizing and managing students' schedules, (b) nurturing relationships and interactions, (c) monitoring and motivating student engagement, and (d) instructing students when necessary. However, teachers believed that parents could act as obstacles to their students' learning by being overly engaged in certain types of learning activities. Additional research is needed that examines parent engagement in a variety of online learning environments. Research that identifies best practices could also be especially valuable to online teachers and administrators wishing to improve the quantity and quality of parental engagement in their programs. 相似文献
63.
徐初 《河南职业技术师范学院学报(职业教育版)》2003,(4):53-56
本研究了英国教育督导制度的发展历史,重点阐述了其现行的督导法规、督导队伍、督导职责、督导方式、督导过程、督导机构等方面的内容,并结合我国教育督导制度的发展现状,提出了一些建设性的意见与完善措施,以促进我国教育督导制度更好地发展。 相似文献
64.
Dirk Ifenthaler Volker Schweinbenz 《Journal of Research on Technology in Education》2016,48(4):306-321
In recent years digital technologies, such as tablet personal computers (TPCs), have become an integral part of a school's infrastructure and are seen as a promising way to facilitate students' learning processes. This study empirically tested a theoretical model derived from the technology acceptance model containing key constructs developed in previous research on the acceptance of technological innovations. On the basis of the research model, it was hypothesized that students' acceptance of tablet PCs could be explained by key constructs and could be distinguished in organizational, individual, and technological factors. The survey research was conducted in three German middle schools, involving a total of 120 students. Overall, participants' attitude toward the TPC positively predicted their behavioral intention to use the TPC and as such had the strongest direct influence. The findings emphasize the importance of understanding factors affecting students' attitudes in order to manage and influence the integration of TPCs in schools. 相似文献
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采用激光干涉的方法,对压电陶瓷的压电特性进行观察和测量.主要是对压电陶瓷的振动幅度和驱动信号周期进行测量计算.采用单片机编程计时计数,计算驱动时间t和干涉条纹移动数目m,再编程算法求出压电陶瓷位移,最后将测量计算值送数码管显示. 相似文献
67.
王卫兵 《雁北师范学院学报》2007,(4)
用电子显微镜(TEM)和程序升温仪(TPR)分别对加钾(K)前后的共沉淀铜钴催化剂[m(Cu)/m(Co)=0.358g]进行了TEM和TPR表征.从TPR图上发现,催化剂加K后,催化剂的还原性受到抑制,导致加K后催化剂活性下降;另外从TEM图上得知,加钾后催化剂的粒径增大,也导致加钾后催化剂活性下降,因此催化剂中钾的加入量应适宜. 相似文献
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Despite the growing call for local autonomy and flexibility, few scholars have examined the role of school district–level flexibility on resource allocation and staffing patterns. Leveraging the charter system law within the State of Georgia, we utilize a generalized difference-in-differences approach to estimate the impact of flexibility of system-level expenditures and staffing changes. We find evidence of increases in central office spending and staffing post-conversion to a charter system. In addition, we find evidence that local support is replaced by the state-funded supplemental funding. 相似文献