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121.
Multidrug resistance (MDR) is the major impediment to cancer chemotherapy. The expression of lung resistance-related protein (LRP), a non-ATP-binding cassette (ABC) transporter, is high in tumor cells, resulting in their resistance to a variety of cytotoxic drugs. However, the function of LRP in tumor drug resistance is not yet explicit. Our previous studies had shown that Kinesin KIF4A was overexpressed in cisplatin (DDP)-resistant human lung adenocarcinoma cells (A549/DDP cells) compared with A549 cells. The expression of KIF4A in A549 or A549/DDP cells significantly affects cisplatin resistance but the detailed mechanisms remain unclear. Here, we performed co-immunoprecipitation experiments to show that the tail domain of KIF4A interacted with the N-terminal of LRP. Immunofluorescence images showed that both the ability of binding to LRP and the motility of KIF4A were essential for the dispersed cytoplasm distribution of LRP. Altogether, our results shed light on a potential mechanism in that motor protein KIF4A promotes drug resistance of lung adenocarcinoma cells through transporting LRP-based vaults along microtubules towards the cell membrane. Thus KIF4A might be a cisplatin resistance-associated protein and serves as a potential target for chemotherapeutic drug resistance in lung cancer.  相似文献   
122.
Searching for an adequate method to investigate human development (especially the development of theoretical thinking) Vygotsky and his collaborators developed the causal genetic method. The basic idea of this method consists in the investigation of psychic functions and structures by their formation under controlled conditions (for instance via a formation experiment in classroom). But is this method also applicable in instructional settings using modern communications media?This paper is an attempt to find an answer to the question: By what means is the investigation of the formation of theoretical thinking realizable through the application of the causal-genetic method in instructional settings using hypermedia and distance learning? However, a closer examination of the question itself shows that there are three interrelated aspects, namely: the investigation and formation of theoretical thinking; distance learning using modern communications media; the causal-genetic method.It will be shown that in a formation experiment learning with a hyper-media-educational program, which is based on the theory of learning- activity, students reach a new level of cognitive development which is characterized by the growing ability of complex and dialectical thinking.  相似文献   
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The early identification of children with learning disabilities (LD) is difficult but can be accomplished. Observation of key behaviors which are indicators of LD by preschool and kindergarten teachers can assist in this process. This early identification facilitates the use of intervention strategies to provide a positive early experience for children at risk for academic difficulties.  相似文献   
124.
In Flanders (Belgium), a new teacher evaluation policy was issued which placed a lot of autonomy with school principals to develop and implement a new teacher evaluation system. In this study, we explore how Flemish principals perceive the new teacher evaluation policy and what influences their perception. Results demonstrate that principals perceive the policy as clear, but they are rather negative about the need, practicality, and complexity of the summative teacher evaluation. This perception is influenced by policy, context, and individual factors as is demonstrated in our qualitative analyses.  相似文献   
125.
The big upper bound of typical van der Waerden number was investigated through calculating the van der Waerden number on a circle. And the van der Waerden number Wh (3,3) = 9, Wh (3,3,3)≥25 on a circle was calculated by computer.  相似文献   
126.
Data-driven decision making continues to be a growing educational reform initiative across the globe. The effective use of data requires that teachers develop the knowledge and skills to analyze and use data to improve instruction. The purpose of this article is to examine teachers’ capacity for and beliefs about data use. These issues are examined through a review of research in the past decade. We find that teachers’ beliefs about and capacity for data use are often not connected within the literature or in practice, but we argue they are the heart of the connection between data and instructional change. Teachers’ capacity to use data and their beliefs about data use are shaped within their professional communities, in training sessions, and in their interactions with coaches, consultants, and principals. However, efforts to develop teachers’ capacity for data use often fall short of their goals. Correspondingly, teachers have varied beliefs about data use, and some feel they lack the ability to use data to inform instruction. In order to be more successful, capacity building should directly address teachers’ beliefs, and data use must be decoupled from external accountability demands and involve a variety of information on student learning.  相似文献   
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Urinary citric acid and calcium levels have been estimated in the urine of 20 normal healthy persons as well as 12 urinary stone patients. Inhibition efficiency of these urine samples towards the mineralisation of urinary stone forming minerals, viz., calcium phosphate, oxalate or carbonate, has been studied in an experimental model. Statistical correlation of the above data has been made by computing the coefficient of determination and unexplained variance. Clinico-biochemical indexing of calcium urolithiasis risk factor has been attempted in the light of the data.  相似文献   
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