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981.
Li-na Pan Yuan Zhang Chang-jun Zhu Zhi-xiong Dong 《Journal of Zhejiang University. Science. B》2017,18(12):1046-1054
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
982.
The recognition of facial expressions in the first two years of life: mechanisms of development 总被引:3,自引:0,他引:3
C A Nelson 《Child development》1987,58(4):889-909
In recent years the infant's ability to recognize facial expressions of emotion has attracted considerable attention from developmental psychologists. The rationale guiding much of this research has been that this ability plays an important role in later socioemotional development. In the present article, the research relating to this topic is reviewed and synthesized. It is concluded that the recognition of facial expressions develops slowly over the first 2 years of life, and that even at the end of the second year the infant's understanding of facial expressions is still quite rudimentary. Following this review is a discussion of 2 unresolved issues regarding the development of this ability. 1 issue relates to the biological/experimental basis on which the ability to recognize facial expressions develops. Research with primates is brought to bear on this point, and useful analogues with human infants are sought. From this research it is suggested that a component of the ability to recognize facial expressions is unlearned, although experience of some as yet undetermined nature affects this biological readiness. The second issue relates to the possible neurological mechanisms that mediate this ability. Research with primates, normal adults, and brain damaged adults is used to support the speculation that a posterior region of the right hemisphere is responsible for mediating the recognition of facial expressions. 相似文献
983.
Hartmut Giest 《European Journal of Psychology of Education - EJPE》2004,19(1):45-64
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
984.
EQUIVALENCE OF QUESTIONNAIRE ITEMS WITH VARYING RESPONSE FORMATS 总被引:1,自引:0,他引:1
985.
Rater‐mediated assessments are a common methodology for measuring persons, investigating rater behavior, and/or defining latent constructs. The purpose of this article is to provide a pedagogical framework for examining rater variability in the context of rater‐mediated assessments using three distinct models. The first model is the observation model, which includes ecological/environmental considerations for the evaluation system. The second model is the measurement model, which includes the transformation of observed, rater response data to linear measures using a measurement model with specific requirements of rater‐invariant measurement in order to examine raters’ construct‐relevant variability stemming from the evaluative system. The third model is the interaction model, which includes an interaction parameter to allow for the investigation into raters’ systematic, construct‐irrelevant variability stemming from the evaluative system. Implications for measurement outcomes and validity are discussed. 相似文献
986.
987.
Marcee M. Steele 《Early Childhood Education Journal》2004,32(2):75-79
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
988.
Working and Playing Together: Prediction of Preschool Social-Emotional Competence from Mother-Child Interaction 总被引:2,自引:0,他引:2
The impact of mother-child interaction on preschoolers' social-emotional competence was evaluated. Twenty-five girls and 23 boys (mean age = 44 mos) and their mothers were videotaped performing four play/teaching tasks. Preschool teachers completed the Baumrind Preschool Behavior Q-Sort and the Behar Problem Behavior Questionnaire. Mother-child interaction aggregates represented task orientation, positive emotion, and allowance of autonomy/reliance on mother. Results indicated that specific maternal interaction aggregates coherently predicted the children's Positive Social Behavior, Assertiveness, and Sadness in the preschool setting. Child aggregates were less effective predictors of teachers' ratings. Several gender differences in the prediction of social-emotional competence were found (e.g., maternal allowance of autonomy predicted girls' sadness, but boys' sadness was predicted by their own negative emotion). These findings' contributions to the parent-child literature are discussed. 相似文献
989.
Do young boys and girls understand what leads to academic success (e.g., talent, effort, good teaching, luck) in the same way? Do young girls and boys have equivalent perceptions of their academic competence? Are these beliefs engendered in the same way across sociocultural contexts? In a cross-cultural study of over 3,000 children in grades 2 to 6, ages 7.2 to 13.6, we discovered that boys and girls around the world have very similar ideas about what generally leads to academic success. Moreover, in the few contexts where boys' and girls' academic performances were equal, their beliefs were also equal. However, when girls outperformed boys, their beliefs in their own talent were no greater than boys' beliefs, even though they did have stronger beliefs than boys in other facets of their achievement potential (e.g., putting forth effort, being lucky, getting their teacher's help). Our findings support the generally close correspondence between children's achievement and their competence-related beliefs, with the exception that young girls appear to specifically discount their talent. The effects held regardless of the children's achievement, intelligence, or age (approximately 8 to 13 years). Girls were more biased in some contexts than in others, however, suggesting that competence-related biases are rooted in culture-specific aspects of school settings. 相似文献
990.
Using Family Backpacks as a Tool to Involve Families in Teaching Young Children About Healthy Eating
Jisoo Hong Diane W. Bales Charlotte R. Wallinga 《Early Childhood Education Journal》2018,46(2):209-221
Children’s obesity rates have increased substantially over the past several decades, due in part to unhealthy eating habits. About 75% of preschool-aged children consume fewer fruits and vegetables than recommended for health. Because children begin developing eating habits during early childhood, obesity prevention programs are increasingly targeting young children in early childhood education (ECE) settings and are involving their families in teaching about healthy eating. The purpose of this pilot study is to assess the effectiveness of a family involvement activity known as the family backpack in increasing fruit and vegetable consumption among 4- and 5-year-old children and their parents through hands-on activities that encourage them to explore and discuss fruits and vegetables at home. Forty-two families (22 experimental, 20 control) participated in the study. Families received a family backpack from their child’s ECE teacher and completed activities with their child at home during a specific week. Experimental-group backpacks contained a children’s book and three activities to encourage parent–child discussion about fruits and vegetables; control-group backpacks contained an unrelated book and activities. Children’s and parents’ fruit and vegetable consumption and frequency of serving fruits and vegetables at home were assessed using parent self-report surveys before and after completing backpack activities. Parents in the experimental group, but not the control group, reported increases in their own and their children’s fruit and vegetable consumption after completing family backpack activities. Family backpacks show promise as a tool for early childhood educators to help families reinforce and expand children’s learning and encourage healthy eating habits at home. 相似文献