三种脑-肠肽对人绒毛膜促性腺激素分泌的影响

本工作利用灌流技术观察了3种脑-肠肽(P物质,CCK及NT)对新鲜人工流产的绒毛hCG分泌的影响。结果表明,P物质,CCK及NT均明显刺激绒毛释放hCG,并发现CCK作用大于P物质及NT。提示,hCG的分泌可能受这3种脑-肠肽的调节。     

高铬铸铁的热处理与二次硬化

利用扫描电镜分析和机械性能测试对15-2-1型高铬铸铁的二次硬化效应进行了研究,并结合合金耐磨性分析探讨了二次硬化效应在高铬铸铁锚喷衬板中的作用.     

Electrostatic effect on electron transfer between cytochrome b5 and cytochrome c

The binding and electron transfer between wild type, E44A, E56A, E44/56A, E44/48/56A/D60Aand F35Y variants of cytochrome b5 and cytochrome c were studied. When mixed with cytochrome c, the cytochrome b5E44/48/56A/D60A did not show the typical UV-vis difference spectrum of absorption, indicating that the alteration ofthe surface electrostatic potential obviously influenced the spectrum. The electron transfer rates of wild type cytochromeb5, its variants and cytochrome e at different temperature and ionic strength exhibited an order of F35Y > wild type >E56A > E44A > E44/48/56A/D60A. The enthalpy and entropy of the reaction did not change obviously, suggestingthat the mutation did not significantly disturb the electron transfer conformation. The investigation of electron transfer rateconstants at different ionic strength demonstrated that electrostatic interaction obviously affected the electron transfer pro-cess. The significant difference of Cyt b5 F35Y and E44/48/56A/D60A from the wild type protein further confirmed thegreat importance of the electrostatic interaction in the protein electron transfer.     

N—烯丙基—N‘—（氨基对苯磺酸钠）硫脲（ASATu）对Cu^2＋的分析研究

利用N-烯丙基-N-(氨基对苯磺酸钠)硫脲在一定介质中与Cu2+产生的特征性反应,进行了Cu2+的鉴定反应条件试验,并确定了鉴定方法.结果表明在氨性介质中,试剂对Cu2+的检出灵敏度为m=0.17μg,c=4.76mg.kg-1,方法的灵敏度高,选择性好.用该法对合成样品、标准样品的分析鉴定都获得了满意结果.     

马颊河水污染控制定量模型

根据物质平衡原理 ,建立点污染源对河流水质影响的定量计算模型 ,进行水污染控制对象 (点污染源 )的优选与治理。     

电火工品的感度控制和非破坏预测

介绍了电火工品用瞬态脉冲试验控制感度的基本方法，讨论了电火工品发火感度无损检测的发展前景，认为发展单发性能预测和相应的仪器有很大的可能性。     

Speed-Sensorless Control Using Elman Neural Network

1. INTanDUCTIONControlling induction motor without sensor is available nowadays. In order to aclileve two-level closed lOops,i. e., digital current lOop and digital speed loop, it is necessary to sense.and digitize the motor phase currentand motor speed. Howver, the sensors involved have the followillg disadvantages. First, they aJre eXPensiveand make up a significan portion of the total cost. Second, they may result in electrical or mechaulcal fault.Based on speed estimation, it is pos…     

几种天然食物抗氧化力比较研究

本文采用邻苯三酚(proglIoi)自氧化法,对几种天然食物大蒜、马铃薯、西红柿、西瓜和黄瓜汁液的抗氧化力进行了比较研究.结果显示:黄瓜汁的抗氧化力最强,黄瓜资源丰富,具有深入开发研究价值.     

<五藏山经>记载的动物地理学知识

<五藏山经>是我国保存下来的最为古老的著作之一,记载了当时我国十分丰富的动物地理学内容.该文从动物名称的考释、动物的地理分布及其动物医学地理学和动物灾害地理学诸多方面对此书进行了详细研究.     

论教师教育的开放性

文章通过分析国外教师教育发展的历史经验和中国国情,认为当前我国教师教育改革的时机已经成熟,并强调教师教育转型、开放的实质是提高教师教育的水平,而不是培养形式的变化.