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1.
Typical university‐wide course evaluations do not provide instructors with sufficient information on the effectiveness of their courses. This article describes a course assessment and enhancement model where student feedback can be used to improve courses and/or programs. The model employs an assessment tool that measures student perceptions of importance and their current competence in course‐specific learning objectives both pre‐ and post‐course. Information gained from this assessment enables course improvement over time and also allows for modification in delivery and/or content of the current course. This model is intended to augment traditional course evaluation mechanisms based on specific and actionable feedback on learning objectives.  相似文献   
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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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The purpose of this paper is to report the findings of a study of library anxiety among a group of Arab students in Saudi Arabia and Egypt. The paper also investigated the factors that affect the students' level of anxiety while using academic libraries. The study tried to compare the difference in the level of anxiety in the two countries using a scale (LLPB) developed by the researchers which fit the culture in the Arab region. The study adopted a mixed methods approach. Semi-structured interviews were conducted with several students in Saudi Arabia and Egypt to determine the main factors that lead to having a level of anxiety in the libraries. In the second stage, a questionnaire was sent to students to measure what factors have a greater impact on the level of anxiety. The data showed that Egyptian students are more anxious about using the libraries than the Saudi students. The results also indicated that there is a need to train students on how to use the libraries and also change students' perception regarding the library to reduce the level of anxiety. This study was conducted in Egypt and Saudi Arabia the level of library anxiety and the factors that may affect the students may vary in other countries.  相似文献   
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In introductory laboratory courses, many universities are turning from traditional laboratories with predictable outcomes to inquiry-inspired, project-based laboratory curricula. In these labs, students are allowed to design at least some portion of their own experiment and interpret new, undiscovered data. We have redesigned the introductory biology laboratory course at Brandeis University into a semester-long project-based laboratory that emphasizes concepts and contains an element of scientific inquiry. In this laboratory, students perform a site-directed mutagenesis experiment on the gene encoding human γD crystallin, a human eye lens protein implicated in cataracts, and assess the stability of their newly created protein with respect to wild-type crystallin. This laboratory utilizes basic techniques in molecular biology to emphasize the importance of connections between DNA and protein. This project lab has helped engage students in their own learning, has improved students' skills in critical thinking and analysis, and has promoted interest in basic research in biology.  相似文献   
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This laboratory study deals with the hydraulic jump properties for an artificially roughened bed with wedge-shaped baffle blocks. The experiments were conducted for both smooth and rough beds with a Froude number in the range of 3.06??F 1??10.95 and a relative bed roughness ranging 0.22??K R??1.4. The data from this study were compared with those of rectangular baffle blocks. New experimental formulae were developed for determining the sequent depth ratio and the hydraulic jump length in terms of the inflow Froude number and relative bed roughness. Bélanger??s jump equation of a rectangular channel was extended to account for the implications of the bed shear stress coefficient attributable to channel bed roughness. It was found that, in comparison with the smooth bed, the wedge-shaped bed roughness reduced the sequent depth of the hydraulic jump by approximately 16.5% to 30% and the hydraulic jump length by approximately 30% to 53%.  相似文献   
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研究了钢纤维掺量和强度等级对超高性能纤维增强水泥基复合材料(UHPFRCC) 宏观性能的影响及UHPFRCC 在荷载与环境因素耦合作用下的耐久性能. 制备了 3 组不同强度等级(100,150,200 MPa) 和不同纤维掺量 (0%,1%,2%,3%) 的高与超高性能水泥基复合材料,并且测试了其各项力学性能和短期耐久性能. 利用设计的预加载装置,在 UHPFRCC150 试件上施加了应力比为 0. 5 的四点弯曲荷载. 结果表明,随着强度等级的增加,在掺加适量钢纤维掺量的情况下,高与超高性能水泥基复合材料的强度和韧性均明显提高,同时其干燥收缩值降低. 对于加载的试件,钢纤维降低了拉应力对 UHPFRCC 抗氯离子渗透性能的不利影响,并且提高了材料的抗冻融性能.  相似文献   
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研究了不同养护制度对超高性能纤维增强水泥基复合材料(UHPFRCC)微观结构和宏观性能的影响,并揭示了用不同的养护制度制备性能符合要求的超高性能纤维增强水泥基复合材料的可能性.制备了一种基准的UHPFRCC,研究了3种养护制度下UHPFRCC的力学性能及短期耐久性能.此外,通过结合运用电子扫描电镜(SEM)和压汞法(MIP),测试了3种养护制度下UHPFRCC的微观结果.研究结果揭示了不同的养护制度对UHPFRCC微观结构的影响以及微观结构对材料宏观性能的影响机制.热养护和蒸汽养护3d与标准养护90 d的UHPFRCC具有相近的力学性能和耐久性.但是,热养护的UHPFRCC具有相对较差的抗氯离子渗透性能.  相似文献   
9.
The purpose of this paper is to report the findings of a study of publishing behaviour among a group of Arab scholars in social science and humanities disciplines. The paper also investigated the number of Arab scholars who are publishing in predatory journals and the reasons that drive them to select these journals to share their scholarly findings. The study adopted a mixed methods approach. Eighteen journals that were categorized as predatory journals were scanned to find the number of Arab scholars who published in them. Then, a questionnaire was sent to Egyptian and Saudi scholars as they were found to be the top Arab contributors in these journals. The questionnaire was followed by semi‐structured interviews to gain an in‐depth understanding of the publishing behaviour. The data showed that many Arab scholars prefer publishing in predatory journals as these journals are easier and faster. The results also indicate that there is a need to raise the awareness of the harm that predatory journals can cause to the scholars and how they can avoid these journals. This study was conducted with social science and humanities scholars in Egypt and Saudi Arabia. The publishing behaviour may differ in other scholarly disciplines and other Arabic countries.  相似文献   
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This retrospective study was conducted to assess the serum lipase / amylase ratio in acute pancreatitis for South Indian population attending the clinics of Gastroenterology and Emergency medicine in the last five years. One thousand one hundred and thirty two patients (768 males and 364 females) with acute pancreatitis (AP) were selected for the study. The diagnosis of AP was based on clinical evaluation, Computed Tomography (CT) findings and biochemical parameters such as serum lipase and amylase. Based on the etiology, the groups were divided into alcoholic, biliary and miscellaneous AP. Based on CT findings, groups were divided into mild, moderate and severe AP. Serum lipase, amylase and lipase / amylase ratio were calculated and statistically analyzed. Serum lipase levels in alcoholic group (3226.3 ± 1384.7) were significantly lower in comparison to biliary (6064.5 ± 1640.8) group though the levels were not significantly different from miscellaneous group (2132.3 ± 1210). Serum amylase values were significantly lower in alcoholic group (923.4 ± 557.5) in comparison to biliary (1736.2 ± 390.7) and there was significant difference between alcoholic and miscellaneous group (535.8 ± 477.6). The serum lipase / amylase ratio > 4 occurred in alcoholic group than with biliary and miscellaneous group. The sensitivity and specificity to predict alcoholic AP with lipase / amylase ratio at >4.0 was 84 % and 59 % respectively. In conclusion the serum lipase to amylase ratio greater than 3.0 could be used to differentiate but keeping the cut off at 4.0 would be of higher sensitivity without much change in specificity. The serum lipase to amylase ratio with a cut off of 3.0 or greater is not useful to differentiate the severe AP from milder AP. Hence, serum amylase and lipase are important for evaluation of pancreatitis though it is not a gold standard for the diagnosis or assessment of severity of acute pancreatitis.  相似文献   
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