Quantum theory of nerve excitation

Based on quantum transitions of membrane dipoles, the four fundamental properties of nerve impulse are derived in this paper: the all-or-none response, the strength-duration relation, refractoriness and refractory period and frequency modulation. Furthermore, the theory offers a physical mechanism for nerve excitation similar to a two-level ammonia maser. It also implies non-threshold excitation at elevated temperatures. The role of trimethylamine ions near the surface of a phospholipid membrane is briefly discussed to indicate a possible connection between theory and reality.     

Principles and applications of luminescence spectrometry coupled to liquid chromatographic techniques

An overview is presented of the physicochemical basis of luminescence, and its application to the detection of chemicals (drugs, biomedically important compounds, environmentally active substances) in liquid chromatographic systems.     

水稻、小麦、油菜和烟草细胞质雄性不育系统中组分Ⅰ蛋白的比较分析

组分Ⅰ蛋白(RuBP羧化酶/加氧酶)的生物合成系由叶绿体基因和细胞核基因共同控制,所以,被作为研究细胞质遗传的标记。本实验用免疫化学和氨基酸成分分析等方法,对水稻(珍汕97)、小麦(繁7)、油菜(湘矮早)和烟草(G28)的细胞质雄性不育系及其保持系的组分Ⅰ蛋白作了比较,同时对不同作物的组分Ⅰ蛋白也作了免疫鉴定。结果表明,细胞质雄性不育系及其保持系的组分Ⅰ蛋白差异不大,但是,四种不同作物的组分Ⅰ蛋白之间有明显差异。     

西昆仑山区高等真菌的研究

本文报道了西昆仑山区和喀喇昆仑山区高等真菌39种,其中我国新纪录4种。     

建兰根状茎增殖条件的研究

研究了建兰两个栽培品种的根状茎在固体及液体两种培养方式,以及培养基中有无激素和不同激素浓度配比对增殖及分化的影响。根状茎在液体培养基上的生长量都大于固体培养基上的生长量。根状茎在无激素的培养基上也能增殖。加入激素有促进作用。合适的激素浓度及配比因品种而异。     

P-glycoprotein: multidrug-resistance and a superfamily of membrane-associated transport proteins

The study of multidrug resistance (MDR) in tumor cell lines has led to the discovery of the plasma membrane P-glycoprotein (Pgp) molecule. This protein functions as an energy-dependent pump for the efflux of diverse anticancer drugs from MDR cells. It now appears that Pgp-mediated MDR tumor cells do occur in human cancers, and that they are likely to play a role in the ultimate response of patients to chemotherapy. Chemosensitizers, compounds able to reverse the MDR phenotype, have been identified and offer the exciting possibility of improving efficacy for some nonresponsive malignancies. Surprisingly, Pgp-like molecules can be found in evolutionarily distant species among both eukaryotes and prokaryotes. As a group, these proteins form a superfamily of ATP-dependent transport proteins. This finding has broad implications and provides new insights into how living organisms use this fundamental transport system to regulate the trafficking of diverse molecules across biological membranes.     

A mutant hemolysin with lower biological activity produced by a mutant Vibrio parahaemolyticus

Abstract A mutant toxin (m-TDH) of thermostable direct hemolysin (Vp-TDH) of Vibrio parahaemolyticus w was isolated from the culture of a strain of this organism mutagenized with N -methyl- N '-nitro- N -nitrosoguanidine. Although the m-TDH had a molecular structure similar to the native Vp-TDH, the m-TDH retained only about 7% residual hemolytic activity of the native toxin. Furthermore, other biological activities of m-TDH, such as lethality in mice and enterotoxicity in rabbit ileal loops, were also weakened. The m-TDH was immunologically indistinguishable from the native Vp-TDH. These results suggest that the m-TDH is only slightly different in structure from the native Vp-TDH. Also, the mutagenized site in m-TDH, which is not immunogenic, seems to be involved in expressing not only hemolytic activity but also lethal and enterotoxic activity.