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Shaymaa M. M. Yahya Shadia A. Fathy Zakaria A. El-Khayat Safinaz E. El-Toukhy Ahmed R. Hamed Marwa G. A. Hegazy Heba K. Nabih 《Indian journal of clinical biochemistry : IJCB》2018,33(1):21-30
Hepatocellular carcinoma (HCC) is a hypervascular primary liver cancer characterized by rapid progression, besides, resistance to traditional chemotherapeutic agents. It has been shown that microRNAs play critical roles in regulation of tumor cell sensitivity to drugs through modulating the expression of genes involved in drug transport. The present study investigated whether restoration of miR-122 in HCC cells could alter the cell cycle distribution and the expression of multidrug resistance (MDR)-related genes (ABCB1, ABCC1, ABCG2 and ABCF2). After overexpression of miR-122 in HepG2 cells treated or untreated with doxorubicin doses, total RNAs and protein extracts were isolated for application of QRT-PCR and western blotting techniques. Moreover, cell cycle distribution was monitored by flow cytometry. Our results revealed that, the over expression of miR-122 in HepG2 cells treated or untreated with doxorubicin could modulate the sensitivity of cells to chemotherapeutic drug through downregulation of MDR-related genes, ABCB1 and ABCF2. Interpretation of cell cycle distribution revealed that, the anti-proliferative effect of miR-122 is associated with the accumulation of cells in G0/G1 phase. Moreover, treatment with miR-122 and doxorubicin resulted in high percentage of HCC cells in G0/G1 phase. Taken together, our findings revealed that, overexpression of miR-122 inhibited HCC cell growth by inducing cell cycle arrest and this arrest is associated with down-regulation of MDR-related genes. 相似文献
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Heba Fasihuddin Geoff Skinner Rukshan Athauda 《Education and Information Technologies》2017,22(3):807-825
Open learning represents a new form of online learning where courses are provided freely online for large numbers of learners. MOOCs are examples of this form of learning. The authors see an opportunity for personalising open learning environments by adapting to learners’ learning styles and providing adaptive support to meet individual learner needs and preferences. Identifying learning styles of learners in open learning environments is crucial to providing adaptive support. Learning styles refer to the manner in which learners receive and perceive information. In the literature, a number of learning style models have been proposed. The Felder and Silverman Learning Styles Model (FSLSM) has been selected as the most appropriate model for open learning. In previous studies two approaches have been used to automatically identify learning styles based on the FSLSM. These approaches are known as the data-driven method and the literature-based method. In the literature, the literature-based method has been shown to be more accurate in identifying learning styles. This method relies on tracking learners’ interactions with the provided learning objects based on a set of pre-determined patterns that help in inferring learning styles. The patterns are monitored based on pre-identified threshold values. This paper aims to apply the literature-based method to open learning environments and introduce the optimal patterns and threshold values for identifying learning styles based on the FSLSM. To achieve this aim, a study was conducted whereby a prototype that simulates the open learning environment was developed and piloted on an undergraduate IT course so that learner behaviour could be tracked and data could be collected. Next, different sets of threshold values from the literature were considered along with some updated threshold values considering the context of open learning environments, and the precision of identifying learning styles was calculated. Eighty-three students participated in the study and used the developed prototype. Precision results from different threshold values presented in the literature along with customised threshold values for this study are reported and analysed in this paper. It is shown that threshold values derived from literature and customised to suit open learning environments provide a high level of accuracy in identifying learning styles. The paper presents the first study of its kind in evaluating threshold values and precision in identifying learning styles based on the FSLSM in open learning environments. The results are promising and indicate that the proposed methodology is efficient in detecting learning styles in open learning environments and useful for developing an adaptive framework. 相似文献
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Judith Lederman Norman Lederman Selina Bartels Juan Jimenez Mark Akubo Shereen Aly Chengcheng Bao Estelle Blanquet Ron Blonder Mariana Bologna Soares de Andrade Catherine Buntting Mustafa Cakir Heba EL-Deghaidy Ahmed ElZorkani Estelle Gaigher Shuchen Guo Arvi Hakanen Soraya Hamed Al-Lal Cigdem Han-Tosunoglu Annemarie Hattingh Anne Hume Serhat Irez Gillian Kay Ozgur Kivilcan Dogan Kerstin Kremer Pi-Chu Kuo Jari Lavonen Shu-Fen Lin Cheng Liu Enshan Liu Shiang-Yao Liu Bin Lv Rachel Mamlok-Naaman Christine McDonald Irene Neumann Yaozhen Pan Eric Picholle Ana Rivero García Carl-Johan Rundgren David Santibáñez-Gómez Kathy Saunders Renee Schwartz Frauke Voitle Jakob von Gyllenpalm Fangbing Wei Jocelyn Wishart Zhifeng Wu Huang Xiao Yalcin Yalaki Qiaoxue Zhou 《科学教学研究杂志》2019,56(4):486-515
Although understandings of scientific inquiry (as opposed to conducting inquiry) are included in science education reform documents around the world, little is known about what students have learned about inquiry during their elementary school years. This is partially due to the lack of any assessment instrument to measure understandings about scientific inquiry. However, a valid and reliable assessment has recently been developed and published, Views About Scientific Inquiry (VASI; Lederman et al. [2014], Journal of Research in Science Teaching, 51, 65–83). The purpose of this large-scale international project was to collect the first baseline data on what beginning middle school students have learned about scientific inquiry during their elementary school years. Eighteen countries/regions spanning six continents including 2,634 students participated in the study. The participating countries/regions were: Australia, Brazil, Chile, Egypt, England, Finland, France, Germany, Israel, Mainland China, New Zealand, Nigeria, South Africa, Spain, Sweden, Taiwan, Turkey, and the United States. In many countries, science is not formally taught until middle school, which is the rationale for choosing seventh grade students for this investigation. This baseline data will simultaneously provide information on what, if anything, students learn about inquiry in elementary school, as well as their beginning knowledge as they enter secondary school. It is important to note that collecting data from all of the approximately 200 countries globally was not humanly possible, and it was also not possible to collect data from every region of each country. The results overwhelmingly show that students around the world at the beginning of grade seven have very little understandings about scientific inquiry. Some countries do show reasonable understandings in certain aspects but the overall picture of understandings of scientific inquiry is not what is hoped for after completing 6 years of elementary education in any country. 相似文献
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Heba A. Mohtady Karen D. Könings Jeroen J. G. van Merriënboer 《Mentoring & Tutoring: Partnership in Learning》2016,24(4):306-317
Informal mentoring is based on a natural match between a junior individual and a senior one who share mutual interests. It usually aids in the professional and personal development of both parties involved. We reviewed the literature regarding factors that make informal mentoring effective within the medical realm, by searching a major academic search engine, Web of Knowledge, for the term “informal mentor*”. Our main research questions concerned the factors that lead to a successful informal mentorship process. A salient finding arising is that the success of informal mentorships hinges on the communication skills of mentor and protégé, their level of commitment, and the chemistry between the partakers. Good informal mentorships impose requirements on both mentors and protégés and rest on shared expectations. 相似文献
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