Changing Perspectives: Exploring a pedagogy to examine other perspectives about stem cell research

This study explores how teachers developed and critically evaluated a range of teaching strategies that could support the discussion of a socio-scientific issue (SSI) that had the potential to be controversial. The issue was stem cell research and six New Zealand teachers of senior biology students (grades 12/13) took part in an action research project that was situational, collaborative and self-evaluative. The focus of the research was to identify communication barriers that interfered with classroom discussion and how teachers could help students cross cultural borders when they discussed SSIs that were outside their life worlds. The barriers to communication were access to relevant science knowledge, religion, language, an inability to question issues and cultural expectations of girls. Teachers trialled and adapted two discussion strategies, ‘Drawing the Line’ and ‘Diamond Ranking’ that provided a vehicle for their students to explore and discuss this issue from a range of perspectives. These discussion strategies enabled their students to take part in a dialogue where reciprocal conversation could occur because they had opportunities not only to explore their own perspectives but also other people's viewpoints.     

医学专科院校细胞生物学教学有效性的探究

细胞生物学是一门高职高专临床医学类基础课程,从细胞的整体水平、亚显微结构水平和分子水来研究生命活动的基本规律。然而细胞生物学内容繁多,看不见、摸不着,枯燥无味,学生没有感性认识,难于理解,所以在教学过程如何解决这一问题成为教学的首要任务。我们要以学生为出发点,提高教学水平。     

Administering the Optimum Dose of l-Arginine in Regional Tumor Therapy

The purpose of this study is optimizing the l-arginine (l-Arg) doses on the basis of chemical structure in regional accessible tumor therapy to settle down a new protocol for the treatment of cancer. ³H-thymidine-based cell proliferation assay was performed in vitro on tumor cell lines of fibrosarcoma (FS), lymphosarcoma-ascitic and on normal cell line of NIH 3T3 after treatment with different concentrations of l-Arg in phosphate buffered saline (PBS). The cultures were harvested after 22 h and the incorporated radioactivity was counted to identify their histologic grades as described in earlier studies. In vivo therapy of murine tumors was conducted where FS cells injected subcutaneously at ventro-lateral position of mice. Various drug delivery schedules were injected into the centre of tumor base, once a day for 4 days. Tumor diameter and survivals were monitored where the day of sacrifice was considered for monitoring the survival period. By identifying the histologic grades of the treated cultures in vitro and in vivo by different concentrations of l-Arg, the corresponding energy of such concentrations were determined. An efficient model with a good fit (R² = 0.98) was established to describe the energy yield by l-Arg dose. The equivalence between the tumor histologic grade and energy of the l-Arg dose delivered in saline (PBS) environment is the optimum condition for regional tumor therapy achieves higher survival rate. The selective cytotoxicity to tumor cells with minimal damage to normal cells by l-Arg due to its chemical structure suggests to be considered the most promising drug for regional therapy of the accessible tumors like breast cancers of early stage with no distant metastasis.     

力学刺激对干细胞增殖分化影响的研究

干细胞受生物化学与生物力学微环境的广泛影响,且前者研究较为深入.生物力学因素对干细胞增殖、分化的调控也有重要影响.力学因素通过调控干细胞生长的微环境,引导干细胞骨架重排,介导细胞内信号转导、影响干细胞的铺展、迁移、取向等行为,进而调控干细胞的增殖及分化.总结近年来国内外生物力学因素对干细胞影响的研究工作,综述生物力学因素对干细胞增殖、分化影响的进展,为深入研究提供基础与思路.     

光伏发电系统在温室大棚上的应用

针对传统农业温室大棚具有电力供应成本高、寿命短、不环保、温控不理想、种植效益低等缺陷,本文提出一种将光伏发电系统与温室大棚相结合的技术方法,并对其原理和应用形式进行分析研究,以达到温室大棚的节能、环保、高效的目的。     

海南高校大学生手机上网现状及不利影响应对策略

手机上网因其高效、便捷受到不少大学生青睐。它给大学生带来必要帮助同时,也带来了对学习、生活、思想、健康等多方面不利影响。2012年暑假,海南师范大学化学与化工学院"高校学生手机上网调查"课题组,根据目前手机上网中存在问题,针对手机上网对大学生产生不利影响进行调查分析,提出应全面加强大学生思想教育及自律与自我教育能力,使大学生更加理性利用手机上网。     

细胞生物学实验教学的改进优化

细胞生物学实验教学是理论与实践相结合的重要环节,是培养学生动手能力和创新能力的有效途径.结合多年细胞生物实验教学实践,在实验的内容设置、取材、操作步骤、药品试剂等方面进行改进和优化,旨在增进学生对实验原理的理解、简化实验过程、节约实验经费,提高实验教学效果.     

Parthenolide inhibits proliferation of vascular smooth muscle cells through induction of G0/G1 phase cell cycle arrest

Objective: This study is to determine the effect of the natural product parthenolide, a sesquiterpene lactone isolated from extracts of the herb Tanacetum parthenium, on the proliferation of vascular smooth muscle cells (VSMCs). Methods: Rat aortic VSMCs were isolated and cultured in vitro, and treated with different concentrations of parthenolide (10, 20 and 30 μmol/L).[3H]thymidine incorporation was used as an index of cell proliferation. Cell cycle progression and distribution were determined by flow cytometric analysis. Furthermore, the expression of several regulatory proteins relevant to VSMC proliferation including IκBα, cyclooxygenase-2 (Cox-2), p21, and p27 was examined to investigate the potential molecular mechanism. Results:Treatment with parthenolide significantly decreased the [3H]thymidine incorporation into DNA by 30%～56% relative to control values in a dose-dependent manner (P＜0.05). Addition of parthenolide also increased cell population at G0/G1 phase by 19.2%～65.7% (P＜0.05) and decreased cell population at S phase by 50.7%～84.8% (P＜0.05), which is consistent with its stimulatory effects on p21 and p27. In addition, parthenolide also increased IκBα expression and reduced Cox-2 expression in a time-dependent manner. Conclusion: Our results show that parthenolide significantly inhibits the VSMC proliferation by inducing G0/G1 cell cycle arrest. IκBα and Cox-2 are likely involved in such inhibitory effect of parthenolide on VSMC proliferation. These findings warrant further investigation on potential therapeutic implications of parthenolide on VSMC proliferation in vivo.     

银杏叶总黄酮对人肝癌HepG2细胞增殖与凋亡的影响

目的探讨银杏叶总黄酮对体外培养的人肝癌细胞HepG2增殖与凋亡的影响。方法将银杏叶总黄酮作用于体外培养的人肝癌细胞HepG2,MTT法检测其对HepG2细胞增殖的影响,缺口末端核苷标记（TUNNEL）法检测其对HepG2细胞凋亡的影响。结果银杏叶总黄酮对体外培养的人肝癌细胞HepG2的增殖效率下降,使凋亡细胞数增加（P〈0．01）,且呈剂量依赖效应。结论银杏叶总黄酮对体外培养的人HepG2细胞增殖有抑制作用,并能诱导细胞凋亡。