HPLC-ICPMS联用技术测定玩具中的三价铬和六价铬

采用HPLC和ICPMS联用技术,将玩具中的Cr(Ⅲ)和Cr(Ⅵ)同时进样分离检测。该方法采用不含铬的惰性色谱柱,优化EDTA与Cr(Ⅲ)的络合温度,保持Cr(Ⅲ)和Cr(Ⅵ)稳定的p H值。结果发现,在70℃水浴温度下,p H值为7.0~7.1,Cr(Ⅲ)与EDTA络合更完全,得出线性相关系数大于0.999 5,检出限满足欧盟玩具标准中三类样品检测要求,常规样品的检测回收率在80%~100%,精密度小于5%,验证了该方法的准确性与可行性。     

基于L-M算法的EV71传播预测模型

本文基于神经网络L-M优化算法,提出一种时EV71病毒的有效预测模型,利用matlab进行仿真模拟,结果和阜阳病毒感染情况非常符合.神经网络L-M优化算法克服了神经网络BP算法收敛速度慢的缺点,同时通过学习训练,本模型的神经系统具有有效性和通用性的特点.     

EMG信号的一种合成方法研究

利用改进了的肌电信号模型，完成了单纤维动作电位（ＳＰＡＰ）和运动单位动作电位（ＭＵＡＰ）的计算机模拟．以此为基础，结合肌肉组织的生理结构和肌电信号的产生原理，首先由多路ＳＰＡＰ信号经过符合生理特性的变换处理后，合成一路ＭＵＡＰ信号，然后考虑人体组织对肌电信号的衰减作用，对具有不同发放率的ＭＵＡＰ序列进行ＥＭＧ信号的合成．这种人工合成的ＥＭＧ信号有助于从理论上研究肌电信号的发放率和传导速度等特性，并将为肌电信号的分解给出一个合理标准．     

多项式模上全次数除法及其在CAGD中的应用(Ⅰ)

本首先介绍了利用Ｇｒｏｅｂｎｅｒ基求解Ｓｙｚｙｇｙ模生成元的方法,在对方法做出进一步分析的基础上,给出了一元模上的多项式辗转相除法,这种除法相对于已有的方法有许多优点。     

Molecular epidemiology and evolution of worldwide enterovirus 71 strains isolated from 1970 to 2004

Human enterovirus 71 （EV71） is one of the major etiological agents of the hand-foot-and-mouth disease （HFMD） that often causes severe neurological complications. Recently, its outbreaks mainly take place in the torrid zone of the Asia-Pacific region. To study the evolution and genetic variability, we collected 532 EV71 strains with almost complete or complete VP1 sequences （891 nt） isolated worldwide from 1970 to 2004. The pairwise homologies and genetic distances were analyzed. Most strains belong to previously identified genotype B and C. However, a unique strain R13223-1ND-01 appears not to fall into current three genotypes （A, B and C）, and probably represents a new genotype D. Some orphan strains were observed in the genotypes B and C, and their significance in the EV71 evolution was discussed. Moreover, there is a significant co-variance of 6 discrete positions on VP1 （amino acid 43, 58, 164, 184, 240 and 249）. This high co-variability is tightly related with the subgenotypes.     

抗EV71多克隆抗体偶联的靶向磁性纳米颗粒对病毒的特异性富集

 手足口病是幼儿和儿童常见的一种传染病,严重时会引起患者死亡。EV71病毒（人肠道病毒71型）是引起手足口病的一种主要病毒。为寻求一条快速诊断EV71病毒感染的新方法,将兔抗EV71多克隆抗体,通过戊二醛交联法偶联在氨基硅烷修饰的磁性纳米颗粒表面,获得抗EV71多克隆抗体偶联的靶向磁性纳米颗粒用于EV71病毒的检测。通过酶联免疫、免疫荧光方法证实了抗体耦合在磁性纳米颗粒表面,并通过BCA法测得其耦合的效率为94.1%。采用抗体偶联的磁性纳米颗粒对EV71病毒液中的病毒抗原进行吸附,通过ELISA法检测上清液中病毒含量的变化,并对磁性纳米颗粒表面吸附的病毒进行免疫荧光和核酸PCR检测,证明了抗体偶联的磁性纳米颗粒可以与病毒抗原特异性结合。由于该纳米颗粒同时具有抗体的靶向性和磁性颗粒的磁响应性,对病毒抗原有较好的特异性吸附能力,可以用于低浓度大样本的EV71病毒抗原的富集检测。利用抗体偶联的靶向磁性纳米颗粒,同时具有可在病毒感染的细胞周围特异性富集和磁颗粒可在交变磁场下感应升温的双重功能,将其作为磁感应热疗的靶向介质,有望研制出病毒感染性疾病磁感应热疗的靶向介质,为靶向热疗病毒感染性疾病提供新的尝试。     

Hot deformation behaviors of WE71 alloy under plain strain compression at elevated temperature

Hot deformation behaviors of WE71 (Mg–7Y-1Nd-0.5Zr) alloy was investigated by plain strain compression tests conducted at temperatures ranging from 350 °C to 500 °C and strain rates varying from 0.01 s^-1 to 10 s^-1. Results show that the hot deformation of WE71 was accompanied by the precipitation of rich Zr phase with granular shape and block-shaped phase rich in element Y. When deformed at low temperature and high strain rate, the softening behavior of the alloy was synergically determined by shear bands propagation, adiabatic heating, twinning formation and dynamic recrystallization (DRX). For the conditions of high temperature and high strain rate, DRX was the major softening mechanism while the formation and annihilation of extension twinning resulted in a special flow curve characteristic at the strain of around 0.3. According to the microstructural observations, it can be concluded that the irregular flow curves of WE71 alloy during plain strain compression process are mainly ascribed to shear bands propagation, adiabatic heating, twinning formation and DRX.     

An Identity-Based Key-Exchange Protocol

An identity-based key-exchange protocol using a bilinear map is proposed and it is proved SK-secure(session key secure) in the AM (authenticated links adversarial model) provided the BDDH (bilinear Diffie-Hellmen) assumption is correct. Then we apply the signature-based authenticator to our protocol and obtain an identity-based key-exchange protocol that is SK-secure in the UM (unauthenticated links adversarial model) provided the BDDH assumption is correct.     

206例重症手足口病的临床分析

目的探讨小儿重症手足口病的临床特征和预后,为客观评估病情提供依据。方法对我医院2015年1月2017年12月共收治206例重症手足口病患儿的临床资料进行回顾分析。结果本组206病例中,1～3岁138例(67%),EV71感染129例(62.6%)。1～2部位有皮疹114例(55.3%),3个部位及3个以上部位92例(44.7%)。持续高热大于3天136例(66%),精神萎靡、烦躁、易惊、惊跳、抖动、呕吐、面色苍白等症状,3个或3个以上症状128(62.1%);白细胞总数大于15×109/L 85例(41.3%)小于4×109/L21例(10.2%);血糖大于8.3 mmol/L60例(29.1%),CK-MB大于48 mmol/L56例(27.2%),痊愈194例(94.2%),神经系统后遗症10例(4.9%),肺出血死亡2例(0.9%)。结论重症手足口病中EV71型多见,以1～3岁儿童好发,皮疹典型或不典型,早期有持续高热、精神萎靡、烦躁、易惊、惊跳、抖动、呕吐、面色苍白等症状,部分白细胞、血糖、CK-Mb等明显异常,该病预后较好,少数病情危重死亡。     

抗CD71人-鼠嵌合抗体的制备及其诱导肿瘤细胞凋亡

目的 :研究在液氮中冻存 2年的转染瘤细胞株 (D2C)复苏后其分泌抗CD71人 -鼠嵌合抗体的特异性、分泌量及诱导肿瘤细胞凋亡的效应。方法 :用ELISA方法检测转染瘤细胞培养上清的抗体分泌量。经DEAE SephadexA 5 0离子交换法纯化产生的抗体 ,并采用SDS PAGE电泳鉴定 ;台盼蓝拒染法观察其对K5 6 2细胞生存的影响 ;细胞计数和MTT试验测定嵌合抗体及鼠源性抗体对K5 6 2细胞的作用 ;琼脂糖凝胶电泳和透射电镜观察K5 6 2细胞凋亡。结果 :Balb/c裸鼠腹腔接种转染瘤细胞后 ,每只裸鼠腹水量在 3～ 5mL。抗体经纯化 ,产量约为 1～ 2mg/mL腹水。经SDS PAGE电泳鉴定 ,在分子量 5 5kD和 2 7kD处 ,可见有抗体IgG重链和轻链的染色条带。抗CD71嵌合抗体及鼠源性抗CD71抗体均可抑制K5 6 2细胞的增殖作用 ,且二者抑制作用无显著性差异 (P >0 .0 5 )。经琼脂糖凝胶电泳和透射电镜观察分别可见抗体诱导的K5 6 2细胞DNA梯形条带和细胞凋亡的形态改变。结论 :液氮中冻存 2年的转染瘤细胞体外生长良好 ,抗体分泌稳定 ,特异性高 ,并可诱导K5 6 2人红白血病细胞凋亡