动物微生态制剂研究应用进展

动物微生态制剂是在动物微生态理论指导下,采用已知且有益的微生物制成的生物制品或活茵制剂．综述了动物微生态制剂的产生起源、益生菌和微生态制剂的概念、微生态制剂所用菌株、作用机理、国内外应用现状及发展前景．     

PET成核剂研究和应用进展

 PET成核剂被用来改善PET晶粒结构、提高结晶速率、增强机械性能、缩短成型周期。常用的PET成核剂可以分为无机成核剂、有机成核剂和复合型成核剂三大类。无机成核剂是应用最早的成核剂,主要有黏土,包括蒙脱土、水滑石等;金属氧化物,包括SiO2、MgO、ZnO、TiO2等;无机盐,包括Na2CO3、NaHCO3、BaSO4等;非碱金属氢氧化物,包括Al(OH)3、Mg(OH)2等。无机类成核剂简单易得,成本低廉。使用简便,但此类成核剂属于异相成核剂,分散性差,成核效果一般;有机类成核剂主要包括苯甲酸盐、乙二胺、离聚物等,其与PET相容性高,成核效果较好,但价格相对较高;复合型成核剂为两种或两种以上不同成核剂复配,例如NaCl/PEO、PEG4000/RCOO-Na+、苯甲酸钠/Surlyn/DER等,不同成核剂之间通常具有协同效应,同时表现出不同成核剂的优点,并且在性能和成本方面具有优势。因此,复合成核剂将成为研究的热点,复合方法、复合工艺、改性机制等将成为复合成核剂研究的方向。     

利用聚丙烯腈废料研制“八○”建筑涂料

讨论了利用聚丙烯腈废料生产建筑涂料的理论依据、制作方法、助剂的选择、技术性能和经济效果。     

Modulation of carcinoembryonic antigen release by HT-29 colon carcinoma line in the presence of different agents

Summary In this study we followed the effects of various differentiating agents on the expression of carcinoembryonic antigen (CEA) released into the medium by a colon carcinoma cell line HT-29. Butyric acid 1 mM markedly increased the level of CEA (12-fold in comparison to control levels). 12-O-tetradecanoyl-phorbol-13-acetate (TPA) 50 ng/ml and 5-azacytidine 4×10^–6M increased the amount of CEA, 2- and 1.5-fold respectively. On the other hand retinoic acid 10^–5M, N methyl-formamide 1% and N,N hexamethylene bisacetamide 2.5 mM decreased CEA 2-, 4- and 3-fold respectively. Our results emphasize that various differentiating agents affect CEA levels differently. Thus changes in CEA levels appear not to be reliable as a marker of a more differentiated phenotype.     

次等茶叶提取咖啡因工艺探究

本文通过大量的实验，找出了提取茶叶咖啡因的较佳条件。在提取过程中主要采取了浸取、蒸馏、升华的方法，并对传统的升华工艺进行了改进。此法较浸取、浓缩、结晶法为优，效果好，得率可达２％．     

Ca-efflux,from direct membrane injury by CCl4, is elicited by amphiphilic vehicles in vitro

Direct membrane injury by CCl₄, in situations excluding metabolic activation, was evaluated in saponin-permeabilized hepatocytes and in microsomes by measuring immediate Ca²⁺ efflux. A good correlation appears between the Ca²⁺ efflux and the level of CCl₄ in the membrane and also the variations in fluidity. Mixtures of CCl₄ with water-soluble vehicles were used to improve the dispersion of CCl₄ in the medium. The mixtures varied in their ability to elicit the membrane effects of CCl₄. The performance of ethanol and, to a lesser degree, other alcohols, suggests the existence of a water stable structural organization between CCl₄ and these amphiphilic vehicles, facilitating the transfer of CCl₄ to the membrane.     

Acylfulvenes,a new class of potent antitumor agents

Acylfulvene, derived from the sesquiterpene illudin S by treatment with acid (reverse Prins reaction), is far less reactive to thiols than illudin S. However, it is reduced readily to an aromatic product, in the same way as illudin S. This may explain its greatly improved therapeutic index compared to that of the parent compound.Unfortunately, publication was held up due to postal delay.     

P_2O_5-Al_2O_3-H_2O系统的水热结晶

本文研究了某些碱性添加物对P_2O_5-Al_2O_3-H_2O系统水热结晶的影响。它们在一定程度上表现出结构导向作用,结晶产物依添加物之种类而变。本文还研究了Al_2O_3源、反应物组成、温度、结晶时间及高压釜内衬材质等因素的影响。实验结果表明,P_2O_5-Al_2O_3-H_2O体系的结晶行为比SiO_2-Al_2O_3-H_2O体系复杂得多,易生成多种结晶相,其中一些具有三维骨架结构。     

人工地貌学初探

探讨了人工地貌学的发展、涵义、影响因素以及人工地貌的特点等问题.     

纳豆菌微生态制剂的研究现状

纳豆菌是日本传统发酵食品纳豆的发酵菌种,是一种对人体无病原性的安全菌株,能耐盐、耐碱、耐高温及挤压,在制粒过程中及通过酸性胃环境均能保持高度的稳定性,是微生态制剂的理想菌株。