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玉米及马齿苋叶片SOD活性诱导研究 总被引:1,自引:0,他引:1
以玉米幼苗及马齿苋作材料,通过甘露醇、H2O2、臭氧和强光等胁迫后,用NBT光化还原抑制法测定叶中SOD活性的变化。臭氧和强光能诱导玉米叶片SOD活性增加。0.5mol/L甘露醇处理玉米叶片12h,SOD活性上升,至48h后下降;在该甘露醇溶液中另外加入10^-2mol/L H2O2;处理12h后SOD活性基本不变。对玉米叶片单独用10^-2mol/L H2O2诱导,30min内SOD活性上升到最高值,随着处理时间的延长又逐渐下降。用耐强光、耐干旱的野生马齿苋作为材料,与玉米相比,其叶片SOD基础活性低于后者;若予以正午强光结合渗透胁迫2h,其叶中SOD活性增幅超过玉米,从种间比较的角度旁证了SOD在抗逆性中的作用。推测植物中存在比活性氧更为直接的物理诱导机制。 相似文献
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The species composition of typically marine fishes in the lower course and mouth area of the Tumen River (Sea of Japan) is examined based on original faunistic collections and literature data. Thirty-three species belonging to 19 families were recorded. The ratio of species of boreal and subtropical origins was found; temporary and seasonal migrants were identified. Some species (Platichthys stellatus, Myoxocephalus stelleri, Strongylura anastomella, and Mugil cephalus) can be considered indicators of the state of the environment. It is noted that yearly surveys of the marine fish composition in the river zone are needed for monitoring climatic and anthropogenic influences. 相似文献
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Su-Jeen Jung Jae-Hyoung Park Sewon Lee 《Journal of Exercise Nutrition & Biochemistry》2014,18(4):355-359
[Purpose]
Arterial stiffness is an independent predictor of cardiovascular risk and may contribute to reduced running capacity in humans. This study investigated the relationship between course record and arterial stiffness in marathoners who participated in the Seoul International Marathon in 2012.[Methods]
A total of 30 amateur marathoners (Males n = 28, Females n = 2, mean age = 51.6 ± 8.3 years) were assessed before and after the marathon race. Brachial-ankle pulse wave velocity (ba-PWV) was assessed by VP-1000 plus (Omron Healthcare Co., Ltd., Kyoto, Japan) before and immediately after the marathon race. Pearson''s correlation coefficient was used to determine the relationship between race record and ba-PWV. In addition, Wilcoxon signed rank test was used to determine the difference in ba-PWV between before and after the race.[Results]
There was no significant change in the ba-PWV of marathoners before and after the race (1271.1 ± 185 vs. 1268.8 ± 200 cm/s, P=0.579). Both the full course record (Pearson''s correlation coefficient = 0.416, P = 0.022) and the record of half line (Pearson''s correlation coefficient = 0.482, P = 0.007) were positively related with the difference in ba-PWV, suggesting that reduced arterial stiffness is associated with a better running record in the marathon.[Conclusion]
These results may suggest that good vascular function contributes to a better running record in the marathon race. 相似文献65.
陈花刘晓英李晓韬李鲜花王富刚 《现代生物医学进展》2014,14(17):3362-3364
细胞生物学是生命科学专业的一门必修的专业基础课,占有非常重要的地位。鉴于我院细胞生物学课程课时安排少、实验少、与已修课程有重复内容、相关科学前沿知识不能及时更新、"填鸭式"教学模式和传统的以"讲"为主的教学方法等严重影响该课程教学质量的教学现状,提出了从课程结构体系、课程教学内容,教学方法及考核方式等方面的一系列改革探究,课程结构体系方面由专业任选课变更为专业基础课,适当增加了理论课时;从课程内容来看,取缔与已修课程的重复内容,适当补充最新科研动态、介绍相关的诺贝尔奖,积极鼓励学生参与教师的相关科研项目和申报大学生科研创新活动项目,培养学生的科研创新能力;从教学模式来看,教师要积极利用图文并茂的多媒体教学、适时放映学生喜欢看的相关电教视频、课堂上多以讨论和提问的方式教学;考核采用平时成绩加期末成绩的方式,不断提高教学效率和课堂管理水平,促进教学质量的提高。 相似文献
66.
目的:对中职药剂专业化学类课程实践技能需求进行调研,为化学类课程实践性教学内容的优化组合提供依据,解决教学中存在内容重复、与生产实际脱节等问题。方法:通过问卷调查和访谈等方法对中职药剂专业化学类课程实践能力需求进行调查,数据统计分析采用了SPSS 13.0统计软件和Excel 2007软件。结果:将中职药剂专业化学类课程实践性教学内容进行优化组合,加强实际需要的实践性操作,剔除过时的陈旧内容。形成基础知识、基本操作技能、验证性实验技术、化学分析和仪器分析实验技术、综合实训、附录等六个模块内容,编撰了《药剂专业化学实训指导》,提出中职药剂专业化学类课程实践性教学的标准。结论:科学合理、与时俱进的实践教学内容能保证学生掌握行业需要的化学类实践技能,达到本专业学生应获得的职业资格证书中相应模块考证的基本要求,成为具有较强实际操作能力的高素质劳动者。 相似文献
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Next‐generation sequencing (NGS) technology is revolutionizing the fields of population genetics, molecular ecology and conservation biology. But it can be challenging for researchers to learn the new and rapidly evolving techniques required to use NGS data. A recent workshop entitled ‘Population Genomic Data Analysis’ was held to provide training in conceptual and practical aspects of data production and analysis for population genomics, with an emphasis on NGS data analysis. This workshop brought together 16 instructors who were experts in the field of population genomics and 31 student participants. Instructors provided helpful and often entertaining advice regarding how to choose and use a NGS method for a given research question, and regarding critical aspects of NGS data production and analysis such as library preparation, filtering to remove sequencing errors and outlier loci, and genotype calling. In addition, instructors provided general advice about how to approach population genomics data analysis and how to build a career in science. The overarching messages of the workshop were that NGS data analysis should be approached with a keen understanding of the theoretical models underlying the analyses, and with analyses tailored to each research question and project. When analysed carefully, NGS data provide extremely powerful tools for answering crucial questions in disciplines ranging from evolution and ecology to conservation and agriculture, including questions that could not be answered prior to the development of NGS technology. 相似文献
70.