双有机改性磁性膨润土对Cu(Ⅱ)和Zn(Ⅱ)的吸附

为了提高膨润土对Cu(Ⅱ)和Zn(Ⅱ)的吸附性能,采用羧甲基纤维素钠(SCMC)和壳聚糖(CS)通过席夫碱反应形成的复合物(SCMC/CS)对磁性膨润土(MB)进行改性,制备SCMC/CS修饰的磁性膨润土(SC/MB),研究改性膨润土吸附Cu(Ⅱ)和Zn(Ⅱ)的性能并分析吸附机理.结果表明,SC/MB对Cu(Ⅱ)和Zn...     

非何杰金氏淋巴瘤 P16 基因纯合性缺失及其临床意义

目的: 探讨 P16 基因纯合性缺失与非何杰金氏淋巴瘤 (NHL) 的关系及其临床意义。 方法: 采用半定量多重 PCR检测了 51 例非何杰金氏淋巴瘤病人P16 基因纯合性缺失情况。结果: 发现 9 例病人出现 P16 基因纯合性缺失, 缺失率为 17.6%, 且低度恶性组与高度恶性组有显著性差异(P <0.05)。 结论: P16 基因纯合性缺失主要发生于恶性程度较高的NHL 中, 可作为判断 NHL 恶性程度高低和决定NHL 治疗策略的一个参考指标。     

新视角解读临床试验中的意向性原则

意向性原则（intention to treat, ITT）是以意向性治疗（即计划的治疗方案）为基础,而不以实际给予的治疗为基础进行评价的原则,在随机对照试验（randomized controlled trial, RCT）中广泛应用。随着临床试验的不断发展和进步,对ITT原则需要重新理解和诠释。在ITT原则的标准定义中,受试者的意向性分组并未特指随机化分组,而是计划的治疗方案,非随机化临床试验中受试者同意入组某一治疗方案同样为一种意向性。在单臂临床试验及非随机化的现实世界研究（real world study, RWS）中,应用ITT原则可评价由患者/医生决定的意向性治疗方案的有效性。在实际应用过程中,应根据研究目的结合ITT原则进行分组策略的综合考虑。     

铝电解槽的“心脏”——炭阳极质量对铝电解生产的影响

本文从生产原料把关、煅烧带温度控制、成型配方优化控制、改善混捏效果、控制焙烧升温速度以及优化电解技术条件等环节提出了提高阳极质量的有效措施,对于降低电解铝生产成本具有重要意义。     

TPU/PA6共混体系的非等温结晶行为

本文采用差示扫描量热法(DSC)研究了聚醚型热塑性聚氨酯弹性体(TPU)/尼龙6(PA6)共混体系的非等温结晶行为。结果表明,随着降温速率的增大,结晶峰温度向低温方向移动;TPU的加入阻碍了共混体系中PA6的结晶,致使结晶峰温和结晶焓随着TPU含量的增加而降低,这是由PA6与TPU之间存在氢键相互作用造成的。     

Dissimilarity in the oxidative folding of onconase and ribonuclease A, two structural homologues

The oxidative folding of frog onconase (ONC), a member of theribonuclease A family, was examined and shows markedly differentbehavior compared to its structural homologue bovine pancreaticribonuclease A (RNase A) under similar conditions. Applicationof a reduction pulse (using a small amount of reduced dithiothreitol)during the oxidative regeneration of ONC indicated the survivalof the native protein along with three other (structured) species,I₁, I₂ and I₃, with the rest of the unstructured species beingconverted to fully reduced protein. Mass spectrometry indicatesthat I₁ has two disulfide bonds, whereas I₂ and I₃ have threedisulfide bonds each. A disulfide mapping method, based on cyanylation,was used to identify I₂ and I₃ as des-[30–75] and des-[19–68],respectively. On enzymatic digestion using trypsin, I₁ was identifiedas des-[19–68, 30–75]. Differences in the intermediatesthat are generated during the oxidative folding of the two structuralhomologues, RNase A and ONC, demonstrate that regenerative pathwaysare not necessarily influenced by tertiary structure. This indicatesthat the lack of a disulfide bond in ONC, analogous to the (65–72)disulfide bond in RNase A which plays an important role in itsoxidative regeneration, does not adversely affect the oxidativefolding of ONC.     

Ionic Liquid-assisted Synthesis of Polyaniline/Gold Nanocomposite and Its Biocatalytic Application

In this report, a novel chemical synthesis of polyaniline/gold nanocomposite is explored using ionic liquid (IL) 1-Butyl-3-methylimidazolium hexafluorophosphate. The direct chemical synthesis of polyaniline/gold nanocomposite was initiated via the spontaneous oxidation of aniline by AuCl₄ ⁻ in IL. A nearly uniform dispersion of polyaniline/Au particles with a diameter of 450 ± 80 nm was produced by this method, which indicates that this method is more suitable for controlling particle dimensions. It was also found that the electrical conductivity of the polyaniline/gold nanocomposite was more than 100 times higher than that of the pure polyaniline nanoparticles. The polyaniline/gold nanocomposite displays superior function in the biocatalytic activation of microperoxidase-11 because of the high surface area of the assembly and the enhanced charge transport properties of the composite material. We also report the possible application of polyaniline/gold nanocomposite as a H₂O₂ biosensor.