大蒜超氧化物歧化酶活性测定及某些性质研究

采用肾上腺素自氧化法对蒜头ＳＯＤ进行活力测定及某些性质研究。结果表明：蒜头粗提取液富含ＳＯＤ，其比活力为４．６０２×１０４ｕ／ｇ蛋白质；它在３０～６５℃及ｐＨ５～ｐＨ９时活力较强；用ＰＡＧＥ分离出两条酶带；能被高浓度的ＫＣＮ、Ｈ２Ｏ２完全抑制，但对氯仿－乙醇液不敏感，说明此酶为Ｃｕ、Ｚｎ－ＳＯＤ。     

无限稀活度系数与选择性分子间引力

本文采用气相色谱法测定了十余种不同溶质在聚乙二醇-400和邻苯二甲酸二壬酯上的无限稀活度系数。应用“选择性分子间引力”的理论,对实验结果进行了理论探讨。     

炸干茸与冻干茸中超氧化物歧化酶活力测定

采用改进的邻苯三酚法测得的炸干茸和冻干茸中超氧化物歧化酶的活力,分别为2400μmol/(min·g)和4880μmol/(min·g),探讨了用超氧化物歧化酶活力作为判定鹿茸的质量指标,以及鹿茸加工工艺是否合理的参考依据之一的可能性。     

Na~+-K~+-Cl~--Br~-水溶液体系中活度系数的测定与计算

用离子选择性电极测定了 ＮａＣ１、 ＫＣ１、 ＫＢｒ、 ＮａＣ１－ＫＣ１、 ＫＣ１－ＫＢｒ和ＮａＣ１－ＫＢｒ水溶液中的电动势，温度为 １０、 ２５、 ３５和 ４５℃，从而求出在上述３个混合电解质溶液中 ＫＣ１、 ＮａＣ１和 ＫＢｒ的活度系数，并将自行改进的 Ｐｉｔｚｅｒ－Ｌｉ方程用于此混合电解质溶液，取得了良好的结果。     

几种离子通道阻断剂对豚鼠离体小肠电活动与收缩活动的影响

本文报告离子通道阻断剂河豚毒素、四乙胺、异博定、硝普钠对豚鼠离体小肠电活动与收缩活动的影响。结果显示:河豚毒素、四乙胺、异博定、硝普钠均不同程度地抑制动作电位与肠肌张力,其中对动作电位的抑制作用是四乙胺>异博定>河豚毒素>硝普钠;对肠肌张力的抑制,在环行肌其抑制作用是河豚毒素>四乙胺>异博定>硝普钠,在纵行肌则是异博定>河豚毒素>硝普钠>四乙胺,这一结果提示:动作电位的形成与Na~+、K~+、Ca~(2+)的跨膜运动均有一定关系,而环肌与纵肌收缩反应的差异可能与肌细胞膜上离子通道的分布和敏感性不同有关。     

Interdependence between locomotor activity and duration of wakefulness in humans during isolation

Summary Locomotor activity was recorded in 14 subjects who lived singly in an isolation unit for 16 to 88 days. Their free-running circadian rhythms had a mean period of 25.9 h, with individual means in the duration of wakefulness () ranging from 12.1 to 22.9 h. Intraindividually, the hourly means of activity were negatively correlated with to such a degree that the total amount of activity per day remained constant irrespective of large variations in .     

Biological activity of enantiomerically pure forms of insect juvenile hormone I and III inBombyx mori

Summary Biological activity of enantiomerically pure juvenile hormones was assayed by topical application on allatectomizedBombyx fourth instar larvae. JHs tested were (10R)-JH I [methyl (2E,6E,10R,11S)-10,11-epoxy-3,11-dimethyl-7-ethyl-2,6-tridecadienoate], (10S)-JH I [methyl (2E, 6E, 10S, 11R)-10,11-epoxy-3,11-dimethyl-7-ethyl-2,6-tridecadienoate], (10R)-JH III [methyl (2E,6E,10R)-10,11-epoxy-3,7,11-trimethyl-2,6-dodecadienoate] and (10S)-JH III [methyl (2E,6E,10S)-10,11-epoxy-3,7,11-trimethyl-2,6-dodecadienoate]. Among these compounds, natural (10R)-JH I was most active and the dose needed to induce 50% larval molting was 0.04 g/larva; it was approximately 12,000 times more active than unnatural (10S)-JH I. Though natural (10R)-JH III showed slight biological activity, it was only one three-thousandth of that of (10R)-JH I. Unnatural (10S)-JH III exhibited no biological activity at the levels assayed.     

苦丁茶不同产地及采收部位抗菌活性成分研究

【目的】研究不同产地及采收部位的苦丁茶抗菌活性及其与5种活性成分之间的相关性,为苦丁茶商品化采摘提供参考。【方法】选用不同产地的、加工及未加工的苦丁茶叶子,采用热水提取苦丁茶;使用杯碟法测定苦丁茶水提物的抑菌活性;经高效液相色谱法同时测定苦丁茶中槲皮素、山萘酚、熊果酸、齐墩果酸的含量,苯酚-硫酸法测定其多糖含量;采用SPSS统计软件将测得的5种活性成分的含量与抑菌活性进行双变量相关性研究。【结果】不同产地苦丁茶水提物的总体抗菌强弱为广西广东海南,且对金黄色葡萄球菌的作用最强,大肠杆菌最弱;加工的未加工的。除山萘酚外,其余4种成分与3种细菌均呈显著性相关(R0.01)。【结论】不同苦丁茶样品的抗菌活性与活性成分含量均有一定的差异;苦丁茶水提物中槲皮素、多糖、熊果酸、齐墩果酸与抑菌活性有显著相关性。