丙型肝炎病毒H株包膜蛋白在昆虫细胞中的表达及意义

目的　获得丙型肝炎病毒 (HCV) H株包膜糖蛋白的重组杆状病毒 ,在昆虫细胞中稳定表达包膜糖蛋白 E1和 E2 ,并初步应用于丙型肝炎患者血清抗体的检测。方法　用 PCR方法自 HCV H株扩增出包膜蛋白 E基因 ,构建重组杆状病毒 ,并在昆虫细胞中稳定表达包膜糖蛋白 E1和 E2。免疫荧光及 Western blot方法鉴定表达产物。用表达的 E1和 E2蛋白与 35例丙型肝炎患者血清反应。结果　昆虫细胞中表达的 E蛋白呈现 3种分子大小 ,E1的相对分子量为 2 1× 10 3和 33× 10 3 ,E2的相对分子量为 6 0× 10 3。在 35份感染者血清中 ,有 4例 E1抗体阳性 ,其中 1例检出 E2抗体。在 9例 PCR检测 HCV RNA阳性而抗 HCV检测阴性的血清中 ,有 3例血清与表达的 E蛋白反应。结论　 HCV E蛋白基因可在昆虫细胞中稳定表达 ,表达的 E1和 E2蛋白可用于 HCV患者的血清学诊断     

X-ray diffraction and electrochemical impedance spectroscopy study of zinc coated LiNi0.5Mn1.5O4 electrodes

Coating and doping with zinc have been used to modify LiNi_0.5Mn_1.5O₄ powders prepared at 700 and 800 °C. As previously found in the literature, surface treatment with zinc leads to a net improvement of the electrochemical performance of the 5-V electrode in lithium cells. X-ray diffraction reveals the occurrence of surface ZnO, which disappears after heating at 500 °C. This indicates that ZnO forms a coating, although zinc can also be incorporated in the LiNi_0.5Mn_1.5O₄ framework. The electrochemical oxidation of both bare LiNi_0.5Mn_1.5O₄ and zinc treated products has been followed by ex situ X-ray diffraction of charged electrodes. For both materials a decrease in the cubic unit cell parameter and the formation of two cubic phases during lithium extraction has been found. Lattice contraction is significantly larger in the sample modified with zinc. EIS measurements give direct evidence of the better stabilization of the electrode surface in the coated material.     

藤茶多糖AGP-3的分离纯化与结构的初步鉴定

目的 对藤茶水溶性多糖进行分离纯化得到AGP-3组分,并对其结构进行初步的鉴定,为藤茶多糖结构与生物活性关系的研究奠定基础.方法 采用DEAE-Sephadex A-25、Sephadex G-200和HPLC对藤茶多糖分离纯化,并通过IR、GC、1HNMR和13CNMR分析对藤茶多糖AGP-3组分的结构进行了初步鉴定.结果 AGP-3重均分子量(Mw)为1.02×105 Da,含中性糖质量分数57.6%、糖醛酸32.3%、蛋白质3.5%.结论 藤茶多糖分离组分AGP-3为一种含蛋白质的复合多糖.     

缬沙坦对急性心肌梗死患者左室结构和功能的影响

目的　观察缬沙坦对急性心肌梗死 (AMI)患者左室结构和功能的影响。方法　将 72例AMI患者随机分为两组 ,常规治疗组 36例 ,口服消心痛 10mg,3次 d;缬沙坦组 36例 ,口服消心痛 10mg ,3次 d ,缬沙坦80mg ,1次 d,并于治疗后 2周、 2 4周分别进行超声心动图和平衡法核素心室造影 ,测定左室心肌重量、左室收缩和舒张功能 ,了解缬沙坦对AMI后左室重塑的阻抑作用。结果　AMI治疗 2 4周时两组患者的室间隔厚度 (IVST)、左室后壁厚度 (LVPWT)、左室舒张末内径 (LVDd)和左室心肌重量指数 (LVMI)、左室射血分数 (LVEF)、左室峰射血率时间 (LPER)、左室高峰充盈率 (LPFR)和左室高峰充盈率时间 (LTPFR)的各均值间差别均有显著性意义 (P<0 0 5 )。结论　缬沙坦能明显减轻心肌梗死后心肌肥厚和左室重塑 ,改善左室功能。     

New insights on P2X purinoceptors

Significant advances in understanding of P_2X purinoceptor pharmacology have been made in the last few years. The limitations of nucleotide agonists as drug tools have now been amply demonstrated. Fortunately, inhibitors of the degrading ecto-ATPase enzymes are becoming available and it has become apparent that the complete removal of all divalent cations can be used experimentally in some systems to prevent nucleotide breakdown. Despite these issues, convincing evidence for P_2X receptor heterogeneity, from data with agonists, has recently been reported.A number of new antagonists at P_2X purinoceptors have also recently been described which to some degree appear to be more specific and useful than earlier antagonists like suramin. It is now apparent that suramin is a poor antagonist of ATP in many tissues because it potently inhibits ATPase activity at similar concentrations to those at which it blocks the P_2X purinoceptor.Advances in the use of radiolabelled nucleotides as radioligands for binding studies has allowed the demonstration of P_2X purinoceptors in a variety of tissues throughout the body including the brain. These studies have also provided evidence for receptor heterogeneity. Excitingly, two P_2X purinoceptor genes have been cloned but operational studies suggest that more than two types exist. The cloning studies have also demonstrated a unique structure for the P_2X purinoceptor which differentiates it from all other ligand-gated ion channel receptors. Further studies on P_2X purinoceptor operation and structure are needed to help resolve controversies alluded to regarding the characterization and classification of nucleotide receptors. Hopefully such studies will also lead to a better understanding of the physiological and pathological importance of ATP and its activation of P_2X purinoceptors. This will require the identification of better drug tools, in particular antagonists which may also provide the basis for novel therapeutic agents.     

抗生素C3221-A的分离及结构鉴定

对嗜热放线菌X3221的发酵液进行溶剂萃取、Sephadex LH-20柱分离、中压控纯化,得到一具有抗菌和抗肿瘤活性的抗生素C3221-A。通过理化性质比较和结构单定确定其为Thermorubin A。     

云芝糖肽的结构组成分析

目的:对云芝糖肽的结构与组成进行研究.方法:采用还原衍生化气相色谱,紫外、核磁、高碘酸氧化、Smith降解、琼脂糖凝胶电泳等方法.结果:云芝糖肽由葡萄糖、半乳糖、岩藻糖、甘露糖、木糖和鼠李糖组成,具有α,β型糖苷键,连接方式有(1→4)、(1→6)两种,含有结合态蛋白,糖肽键类型初步确定为N-连接.结论:首次对云芝糖肽的化学结构与组成进行了较为细致的研究.     

一种LDL吸附剂载体-聚丙烯酰胺微球的合成及应用

研究用于低密度脂蛋白 (L DL)吸附的聚丙烯酰胺微球载体的合成工艺、结构特性及吸附 L DL 的性能 ,为进一步研发 L DL 吸附剂载体提供实验依据。采用反相悬浮聚合法按一定的配方合成聚丙烯酰胺微球载体 ,通过扫描电镜、图像分析仪、X光小角散射等手段对其结构特性 (粒径、孔径等 )进行表征 ;同时在微球上固定丝氨酰 -天冬氨酰 -谷氨酸 (SDE)三肽配体制成 L DL 吸附剂 ,通过体外静态吸附对其吸附性能进行了初步研究。结果表明微球粒径为 14 2 .1μm,孔径为 119.8nm,符合作为 L DL 吸附载体的需要 ;在交联剂与单体总量一定的条件下 ,微球孔径随着交联剂用量的增加而减小 ;合成的聚丙烯酰胺微球对 L DL 的非特异性吸附很小 ,而在其上偶联配体制成吸附剂后 ,又表现出对 L DL 的特异性吸附。本实验合成的聚丙烯酰胺微球是一种有效的 L DL 吸附剂载体。     

四元胶乳互穿聚合物网络的组成对其性能的影响

用分步乳液聚合法合成了具有核壳结构的胶乳互穿聚合物网络ＬＩＰＮ（ＰＭＭＡ－ＰＳ）／（Ｐｎ－ＢＡ－ＰＡＡ）；讨论了ＬＩＰＮ组成对乳液与膜性能的影响，提出了四元ＬＩＰＮ核壳结构的基本轮廓，探讨了软硬单体最佳配比及丙烯酸单体用量。     

生脉散多糖的组成及其初级结构分析

目的：研究复方中药制剂中多糖与单方多糖之间的组成关系，以及生脉散多糖的初级结构分析。方法：提取和精制了生脉散（SMS）单方药材红参、麦冬、五味子中多糖成分；然后采用Sephadex G-75柱层析分离纯化SMS多糖，得一浅黄色SMS多糖纯品，经紫外光谱、Sephadex G－200凝胶柱层析和琼脂糖凝胶电泳检测证明为均一组分。同时采用Sephadex G-200凝胶柱层析，测得SMS多糖组成。运用TLC法和HPLC法测定了SMS多糖纯品的单糖组成；并采用IR，高碘酸氧化和Smith降解推知其初级结构。结果：SMS多糖由红参多糖，麦冬多糖和五味子多糖所组成，其中含有葡萄糖、L－鼠李糖、D－木糖、D－果糖、半乳糖和乳糖等多种单糖，主要糖苷键为α－构型；多糖糖苷键以1→4连接键为主，1→3为次。结论：首次报道了生脉散多糖的组成及其初级结构分析。