人体下颌骨前伸后的骨应力研究

通过CT技术获取人体下颌各层面的解剖轮廓图,经三维重建从生物力学角度分析下颌前伸后下颌不同部位的应力情况.选择一处于生长发育高峰期的典型Ⅱ类患儿,采用CT技术对整个下颌骨进行断层扫描,将其输入计算机给定前伸条件咬合重建,在CAD软件中建立几何模型,将其导入MSC.PATRAN建立有限元模型.结果显示髁突后缘及下颌体磨牙区出现拉应力集中区,下颌骨下缘及下颌角区为压应力集中区.本实验对下颌前伸后下颌内部的应力情况进行了客观分析,从理论上推断并支持了功能矫治后下颌骨的生长改型变化.     

Cu（Ⅱ） effect on the conformation of regenerated silk fibroin in dilute aqueous solution

Much attention has been paid to the natural mechanism of silkworm spinning due to the impressive mechanical properties of the natural fibers. In this work, we studied the effect of Cu（Ⅱ） ions on the secondary structure of Bombyx mori regenerated silk fibroin （SF） in dilute solution by circular dichroism （CD）. The results indicate that a given amount of Cu（Ⅱ） induces the SF conformational transition from random coil to β-sheet, however, further addition of Cu（Ⅱ） is unfavorable for this conversion. Meanwhile, the conformational changes induced by Cu（Ⅱ） follow a nucleation-dependent aggregation mechanism, which is similar to that found in Prion protein （PrP） denaturation and Aβ-peptide aggregations, leading to the neurodegenerative disease. This work would help one understand further the natural spinning process of silkworm. Additionally, it would be significant for the study of the nervous system diseases, because silk fibroin, extracted in large amounts from Bombyx mori silkworm gland, could be a proper model to study PrP denaturation and Aβ-peptide aggregations.     

构建人性的神话——试论他者视角下二战题材电影《南京! 南京!》和《硫磺岛家书》

《南京!南京!》和《硫磺岛家书》均采用了＂他者＂视角编织出人性神话。《南京!南京!》中的＂他者＂视角是国际化浪潮中电影的价值观与世界接轨的大胆尝试,而《硫磺岛家书》则是直接源自美国主流意识形态所倡导的人性观。这种普适性的人性视角忽略了具体历史文化环境中特殊的人性,规避了对沉重的历史真相的阐释,存在对日本文化的误读。     

上海市白龙港片区污水治理南线工程简介

为缓解已建南干线、中线处理能力和实际处理负荷之间的矛盾,分担已建干线的输送压力,启动南线输送干线工程。通过对工程范围内水量预测、水力计算和各施工方案比选,本工程拟建设2根DN4000管道,采用顶管施工,输送至白龙港污水厂,解决浦西和浦东地区日益增加的污水问题,改善水域环境质量。     

对ERP概念的解析——浅谈对ERP的认识

主要通过解析ERP概念,介绍了ERP的发展历程、管理思想、组成以及ERP与MRP Ⅱ的区别,说明ERP在生产管理中的重要作用。     

蒙脱土担载钴(Ⅱ)-邻菲罗啉金属配合物的制备与表征

本文首次合成了蒙脱土担载钻(Ⅱ)—邻菲罗啉金属配合物,并对其结构进行了IR、XRD、TEM及TG 的表征。     

双路及时锁存分时进入的快接口电路

在核物理实验中,常常需要对多路脉冲信号进行幅度分析及数据获取.通常使用多路模拟混合方式予以实现,也有采用DMA链的方式.本文介绍的接口电路不用模拟混合器,而采用对两路ADC变换的二进制码分别进行及时锁存、DMA分时进入的方式来实现两路数据获取,线路的组成比较简单而传送速率较快.本接口电路主要分为四个部份:顺序控制电路产生顺序控制信号,以保证两路数据代码按“先来先送,后来后送”的原则进入地址总线;地址形成电路将ADC变换的数据代码及予置的高位地址代码,变成对应两路数据存贮区的RAM 1所需的地址码;     

Measurement of trace lead (II) in water samples with biomacromolecule heparin modified electrode

A new method for electrode modification and accumulation with a biomacromolecule and subsequent voltammetric quantittion of metal ions is described. Heparin is used as the surface modifier, and the method is based on formation of the heparin complex of lead (II). The voltammetric responses were evaluated with respect to electrolyte, pH, preconcentration time, and lead concentration. The electrode composition, voltammetric wave form and other variables have also been taken into account. A detection limit of 3.0×10⁻⁹ mol/L has been obtained by preconcentration for 20 min. The method is sensitive, simple and relatively rapid, with a relative standard deviation of 5.2% at the 1.0×10⁻⁷ mol/L level. Supported by the Trants-Century Training Program Foundation for the Talents from the State Commission of Education of China: the national Natural Science Foundation of China and the Opening Laboratory Foundation of Changchun Institute of Applied Chemistry, Chinese Academy of Sciences. Li Huiling: Born in July 14, 1972. Master of Science.     

Isolation and characterization of biologically active lectin from Korean mistletoe, Viscum album var. Coloratum

A mistletoe lectin was isolated from water extracts of Korean mistletoe, a subspecies of Viscum album, grown on Quercus mongolica using CM-Sepharose chromatography followed by an affinity chromatography on a concanavalin A-Sepharose column. The compound proved to be a mistletoe lectin II with D-galactose and N-acetyl-D-galactosamine specificity. Matrix-assisted laser desorption time-of-flight mass spectroscopy showed it to have an average molecular mass of 62.7 kDa and to consist of two subunits of 30.6 kDa and 32.5 kDa. It was a basic protein with isoelectric points of 9.4 and 9.6 by capillary isoelectric focusing and was cytotoxic to Molt4 cell. Received 17 November 1998; received after revision 3 March 1999; accepted 3 March 1999     

水合4-氧-1(4H)-吡啶乙酸锰配合物[Mn(H2O)6](4-OPA)2·2H2O的合成与晶体结构

利用氯化锰与4-氧-1(4H)-吡啶乙酸反应合成了一个新的配合物[Mn(H2O)6](4-OPA)2·2H2O(4-OPA-=4-氧-1(4H)-吡啶乙酸根),并对其进行了元素分析、IR光谱和单晶X射线的表征。配合物晶体属单斜晶系,空间群为P21/c,晶胞参数为a=1.2561(3)nm,b=1.2949(3)nm,c=0.68547(14)nm,β=98.68(3)°。V=1.1022(4)nm3,Z=2,Mr=503.32,最终R=0.0319,wR=0.0827。Mn(Ⅱ)原子与六个水分子配位形成八面体构型,4-氧-1(4H)-吡啶乙酸根作为抗衡阴离子,配阳离子与阴离子之间通过静电吸引和氢键作用形成了三维氢键超分子网络结构。