研究性学习活动的设计与实施

随着新课程计划的实施,作为培养创新精神和实践能力的研究性学习活动已在不少省市展开,为了避免活动的盲目性,本文就研究性学习活动设计与实施中的目标、内容、程序及评价等作必要的探讨.     

Cardioprotective activity of synthetic guggulsterone (E and Z-isomers) in isoproterenol induced myocardial ischemia in rats: A comparative study

Guggulsterone, a mixture of cis (E) and trans (Z) isomers (7∶3 w/w) was synthesized from 16-DPA. The isomers were separated by column chromatography and evaluated for cardioprotective and antioxidant activities. Myocardial necrosis induced by isoproterenol in rats caused marked increase in serum creatine phosphokinase and glutamate pyruvate transaminase. Simultaneously in ischemic heart, phospholipase, xanthine oxidase and lipid peroxides were enhanced following depletion of glycogen, phospholipids and cholesterol. Treatment with guggulsterone and its both isomers at the dose of 50 mg/kg po., significantly protected cardiac damage as assessed by the reversal of blood and heart biochemical parameters in ischemic rats. The cardioprotective activity of guggulsterone and of both the isomers were compared with that of gemfibrozil at the same doses. Guggulsterone and both the isomers at tested concentrations (5–20mM) inhibited oxidative degradation of lipids in human low-density lipoprotein and rat liver microsomes induced by metal ionsin vitro. The drug counteracted against the generation of superoxide anions (O₂) and hydroxyl radicals (OH⁻) in non-enzymic test systems. It is suggested that cardioprotective and antioxidant activities of synthetic guggulsterone and guggulsterone obtained from gum resinCommiphora mukul that contains isomers E & Z in the ratio of 46∶54w/w are the same.     

Acrosin activity in spermatozoa of infertile Nigerian males

The objective of this study was to evaluate acrosin activity in spermatozoa of infertile Nigerian men and to compare with those of the fertile men. The acrosin activity was evaluated using the Acroscreen reagent kit. The acrosin activity of the fertile men was 40.7±5.2 mIU/10⁶ sperm (range 30.1–51.3) and those of the infertile men was 22.4±8.33 mIU/10⁶ sperm (range 5.7–39.1). The difference in the mean was statistically significant (P<0.001). There was a subpopulation of the infertile men who had their acrosin activity within normal range of the fertile men, 32.9±1.57 mIU/10⁶ sperm. But the difference in the mean was statistically significant (P<0.001). Acrosin activity decreased with increased morphological changes in the spermatozoa. It is concluded that acrosin activity in the infertile Nigerian men is significantly lower than that in the fertile men. Acrosin activity may also be affected by morphological changes in the spermatozoa.     

不同品系小鼠自发活动特点及中枢抑制药新评价模型

目的用开场实验研究NIH、ICR、昆明种小鼠自发活动特点,并以戊巴比妥为工具药建立药物中枢抑制作用新的评价模型.方法用开场实验观察小鼠进入新环境的自发活动特点,并用计算机图像处理系统记录,分析小鼠30 min内的活动轨迹,观察不同时间段的总路程、中央逗留时间、中央路程3个参数.还观察了腹腔注射不同剂量戊巴比妥对自发活动特点的影响.结果各种小鼠总路程在前10 min明显大于后20 min (P < 0.001) ;中央逗留时间和中央路程变化较小,但存在一定的品系和昼夜差异.戊巴比妥可减少ICR和NIH小鼠(昆明种小鼠无效)的总路程,但无典型的量效关系;但可剂量依赖性减少各种小鼠中央逗留时间和中央路程(P < 0.01).结论本实验建立的方法能反映小鼠自发活动特点,并可用于评价中枢抑制药作用,其中中央逗留时间和中央路程是稳定、敏感的指标.     

在实践性阅读教学活动中让学生“活”“动”起来

新课标强调了语文实践的重要性,而实践性阅读教学活动把本来单调、枯燥、乏味的语文知识传授用生动有趣的教学形式组织起来,使学生乐学、会学,活学活用,达到寓教于乐,寓学于用的目的,让学生真正成为了学习的主人。同时,也使教师真正成为了学习的组织者和引导者。实践性语文阅读教学活动要注重活动的情趣性、自主性、整合性,使学生在课堂学习中"活"、"动"了起来,从而促进学生主动、生动、活泼地发展。     

贫困农村儿童课外信息获得现状及价值分析——以永州市为例

农村儿童是农村社会的未来中坚.他们是否得到良好教育,将会对社会稳定、经济发展和道德进步产生重要影响.从调查的结果来看,贫困农村儿童课外信息获得既具有"激发学习兴趣"、"去蔽"、"榜样"等积极价值影响,也有"影响身体健康"、"不良媒介文化教养"、"产生挫败感"等消极价值影响.     

农林院校艺术教育的现状及对策

加强高校艺术教育是时代发展的必然要求,是社会对综合素质人才的呼唤。目前,我国农林院校艺术教育的现状是活动质量低下、艺术教育体制机制不健全、艺术教育观念陈旧、艺术教育师资队伍不合理、教师素质有待提高。改善我国农林院校艺术教育的现状,就要丰富艺术教育活动,建立健全艺术教育活动体制机制,更新艺术教育观念,优化艺术教育师资队伍。     

旅游活动对吐鲁番维吾尔族传统手工技艺保护的影响研究

改革开放以来,吐鲁番地区旅游业的发展取得了喜人的成绩,同时,吐鲁番地区拥有类型多样的维吾尔族传统手工技艺。文章以旅游活动为视角,重点分析了旅游相关群体即政府部门、旅游企业、当地居民和旅游者对吐鲁番维吾尔族传统手工技艺保护的态度,在此基础上,探讨了旅游活动对传统手工技艺保护的积极影响和消极影响,并进一步分析了二者之间的关系。     

发挥国际联合实验室优势 推进学生科技创新活动

提高大学生的创新精神和创新能力是时代的要求,是我国高等教育的重要使命。国际联合实验室具有软件、硬件、激励机制3个持续开展大学生科技创新活动的必要条件。以哈尔滨工业大学罗克韦尔自动化实验室为例,具体介绍了发挥国际联合实验室的优势,通过3个阶段推进学生科技创新活动。     

Investigating populations via penguins and their poo!

We describe an activity that introduces students to population modelling, enables them to use estimates obtained from a sample to infer back to the population, and understands how the findings are translatable via penguins and their poo!