仲烷基磺酸钠SAS生产概况及今后发展建议

1 前言本世纪末随着我国产业政策的调整,表面活性剂工业正蓄势待发,面临着最好的发展时机。阴离子型表面活性剂是品种最多产量最大的一类,其中最主要的品种有烷基苯磺酸盐-LAS。1995年产量约15万t;其次是醇醚硫酸盐-AES,1995年产量4万t左右;其它超过千吨的品种有磺氯酰化法生产的烷基磺酸盐AS、油酰甲基牛磺酸钠lgepon-T、十二烷基硫酸钠K12、油酰多     

METABOLIC KINETICS OF BRAIN MUSCARINIC CHOLINERGIC RECEPTORS IN NORMAL AND HYPOTHYROID MICE

A technique for studying in vivo the production rate and turnover rate constant of mouse brain M-receptors was established. A single injection of 25 mg / kg of Benzilylcholine Mustard to living mice resulted in 90 % irreversible block of brain M-receptors. The time course of the receptor density was then monitored by 3H-QNB binding assay and the production rate and turnover rate constant were calculated from the time course curve with a computer program. It was found that in normal mice the turnover rate constant was about 0.035 h-1 (half-life was about 20 h) and the production rate was 30-42 fmol / (h ·mg protein). Parallel experiments revealed a significant slow down of the turnover of brain M-receptors in hypothyroid mice (turnover rate constant was 0.0257±0.0012 h-1 in hypothyroid vs. 0.0356±0.0021 h-1 in normal) while the production rate was not changed significantly. The results suggest that thyroid hormones have a regulatory action on the turnover of brain M-receptors and the elevation of brain M-receptor density together with slow down of the turnover of brain M- receptors is probably one of the important mechanisms relevant to the brain dysfunction in hypothyroidism.