孤子理论新进展

回顾孤子理论发展历程，综述近几年孤子理论的新进展．介绍几种高维、耦合和微扰的孤子方程的求解方法及定性分析方法，讨论孤子理论在生物物理学、超导材料的Josephson效应、光纤通讯以及流体力学等方面的应用，分析这一理论与耗散结构论和混饨理论之间的联系，展望了孤子理论的发展和应用的前景．     

核黄素与脱氧核糖核酸相互作用的液滴荧光法研究

在接近人体生理pH条件下,采用紫外光谱法和液滴荧光法研究了核黄素和小牛胸腺DNA的相互作用.研究结果表明,随着DNA浓度增加,核黄素产生紫外光谱减色效应及荧光猝灭效应.进一步研究发现盐效应可使核黄素的荧光猝灭效应减小,由此推测核黄素与DNA之间可能存在嵌入作用和静电结合作用.通过计算和Scatchard作图求得该反应的结合常数与结合位点数.     

Oswald Avery and the identification of DNA as the genetic material

In February 1944, when the whole world was consumed by the ravages of a World War, an important paper appeared in the rather obscure Journal of Experimental Medicine, entitled “Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types: Induction of Transformation by a Deoxyribonucleic Acid Fraction Isolated from Pneumococcus Type III”. The principal author of the paper was a short, soft-spoken physician of Canadian origin, Oswald Theodore Avery. The carefully reasoned paper of Avery and his colleagues at the Rockefeller Institute in New York, Colin MacLeod and Maclyn McCarty, was the culmination of meticulous work carried out for over a decade, following the startling results on pneumococcal transformation reported by the British physician Frederick Griffith in 1928. Though the paper was initially met with scepticism from the scientific community, it went on to pave the way for ushering in the new field of molecular genetics. It was also the inspiration for a young American graduate student by the name of James Watson, to team up with the British biophysicist Francis Crick, to solve the structure of DNA. This article attempts to highlight the triumphs and disappointments in the pursuit of the identification of the “transforming principle”. S Mahadevan works and teaches at the Indian Institute of Science, Bangalore. His areas of interest are microbial genetics, physiology and evolution.     

电化学DNA生物传感器应用现状

对电化学DNA生物传感器的基本原理作了介绍,对近期有关其应用的文献加以分类和评述,并对其发展进行了展望。