膜蛋白三维结构研究的新突破——线粒体呼吸链膜蛋白复合物II结构解析

由清华大学-中科院生物物理所结构生物学联合研究小组完成的“线粒体呼吸链膜蛋白复合物II的晶体结构”研究成果以Article的方式发表在2005年7月1日出版的Cell上。本文介绍了该项成果的研究背景、意义、主要创新点及方法。     

两种体系中甘氨酸合铜配合物稳定常数的测定

采用pH电位滴定法研究了甘氨酸水溶液和甘氨酸钠水溶液两种体系中甘氨酸与铜离子间的配位作用,测定了两种体系中甘氨酸与铜配合物的逐级稳定常数;对影响测定准确度的原因进行了详细的分析,采用Origin 6.0计算机软件包来处理实验数据和作图。     

基于FPGA的信号发生器的设计

介绍了基于FPGA的信号发生器的设计。通过对系统进行结构分析,采用层次化的设计方法,给出了信号发生器的VHDL程序,利用MAXPLUS II对其程序进行了仿真,并给出了仿真结果。     

Including Inquiry-Based Learning in a Flipped Class

Abstract

Flipped classrooms and inquiry-based learning (IBL) have each become popular in their own right, leading to a natural question: Why not combine these two great ideas? Although flipping a class usually involves students reading or watching videos before class, and IBL focuses on allowing and encouraging students to develop material on their own, both styles emphasize active learning and critical thinking through activities such as group work and presentations while minimizing lectures. In this article, I discuss ways that the two teaching styles can complement each other and be implemented concurrently, with some examples from my flipped calculus II course. Throughout this discussion the focus remains on ways to keep students engaged and how to instill deep content knowledge.     

μC/OS II下LwIP协议的移植实现

本文主要讨论了如何在嵌入式实时操作系统μC/OSII下移植实现LwIP这套TCP/IP协议栈,使μC/OS II成为支持网络的RTOS。     

商洛茶叶中痕量锰催化光度法测定

茶叶中含有痕量锰,采用Mn(Ⅱ)—甲酚红—氨三乙酸—NH3.H2O—KIO4体系进行催化氧化光度法测定,灵敏度可达6.1×10-10g/mL,选择性高,常见的二十余种阴、阳离子均无干扰,结果重现性好.结果表明,商洛出产的几种茶叶含锰量均略高于被测试的几种外地茶叶.     

Low‐intensity pulsed ultrasound ameliorates angiotensin II-induced cardiac fibrosis by alleviating inflammation via a caveolin-1-dependent pathway

ObjectiveCardiac hypertrophy and fibrosis are major pathological manifestations observed in left ventricular remodeling induced by angiotensin II (AngII). Low-intensity pulsed ultrasound (LIPUS) has been reported to ameliorate cardiac dysfunction and myocardial fibrosis in myocardial infarction (MI) through mechano-transduction and its downstream pathways. In this study, we aimed to investigate whether LIPUS could exert a protective effect by ameliorating AngII-induced cardiac hypertrophy and fibrosis and if so, to further elucidate the underlying molecular mechanisms.MethodsWe used AngII to mimic animal and cell culture models of cardiac hypertrophy and fibrosis. LIPUS irradiation was applied in vivo for 20 min every 2 d from one week before mini-pump implantation to four weeks after mini-pump implantation, and in vitro for 20 min on each of two occasions 6 h apart. Cardiac hypertrophy and fibrosis levels were then evaluated by echocardiographic, histopathological, and molecular biological methods.ResultsOur results showed that LIPUS could ameliorate left ventricular remodeling in vivo and cardiac fibrosis in vitro by reducing AngII-induced release of inflammatory cytokines, but the protective effects on cardiac hypertrophy were limited in vitro. Given that LIPUS increased the expression of caveolin-1 in response to mechanical stimulation, we inhibited caveolin-1 activity with pyrazolopyrimidine 2 (pp2) in vivo and in vitro. LIPUS-induced downregulation of inflammation was reversed and the anti-fibrotic effects of LIPUS were absent.ConclusionsThese results indicated that LIPUS could ameliorate AngII-induced cardiac fibrosis by alleviating inflammation via a caveolin-1-dependent pathway, providing new insights for the development of novel therapeutic apparatus in clinical practice.     

催化动力学吸光光度法测定痕量锌

根据锌 (Ⅱ )能催化过氧化氢氧化氯化 3,7—双 (二甲氨基 )噻咛褪色反应的原理 ,提出了催化动力学吸光光度法测定痕量锌的定量分析方法 在最大吸收波长 6 6 0nm处 ,锌 (Ⅱ )在 0 8～ 2 7μg/2 5mL范围内呈线性关系 ,检出下限为 1 6× 10 -1 0 g mL-1 方法用于人发中锌的测定 ,结果使人满意     

微型化学实验刍议

主要阐述以氢气还原氧化铜的微型化学实验组织教学,取得良好的教学效果．     

运动对心脏肾素-血管紧张素系统的影响

采用文献资料法,分析了循环和局部的肾素—血管紧张素系统的产生及作用机制;探讨了运动对心脏肾素—血管紧张素系统的影响;提出运动使心脏血管紧张素Ⅱ及受体的表达发生改变,肾素—血管紧张素系统参与机体水、电解质平衡的调节及运动心脏的重塑。