A novel type of polyurethane and polyether-polyimide blends were prepared in two steps. The first step was the preparation of polyether-amic acid by the reaction of an oligmer based on polytetramethylene oxide glycol ...A novel type of polyurethane and polyether-polyimide blends were prepared in two steps. The first step was the preparation of polyether-amic acid by the reaction of an oligmer based on polytetramethylene oxide glycol di-p-aminobenzoate (APTMO) of different molecular weight with benzenetetracarboxylic acid dianhydride (PMDA). The second step was mixing polyether-polyurethane and polyether-polyamic acid solution at room tem- perature in various weight ratios and the blend films were obtained by casting and then heating imidization .In- frared spectroscopy, dynamic mechanical analysis,differential scanning calorimetry,, wide-angle X-ray diffraction and sham-sires testing were used to study this family of blends. DMA and DSC results show that the blends exhibit a well phase-separated morphology and possess a wide range of service temperature, which varies with the PU content. The thermal stability of PU is found to increase obviously by the incorporation of PI. The excellent tensile properties of the blends suggest that they could be potentially ed as heat resistant thermoplastic elas-tomers.展开更多
采用噬菌体展示肽库技术筛选雷公藤内酯醇的靶蛋白,得到了一个肽段,并通过酶联免疫吸附(ELISA)和免疫共沉淀验证了该片段对雷公藤内酯醇的结合特异性。用Basic Local Alignment Search Tool(BLAST)进行序列对比后,找到了77个匹配序列,...采用噬菌体展示肽库技术筛选雷公藤内酯醇的靶蛋白,得到了一个肽段,并通过酶联免疫吸附(ELISA)和免疫共沉淀验证了该片段对雷公藤内酯醇的结合特异性。用Basic Local Alignment Search Tool(BLAST)进行序列对比后,找到了77个匹配序列,其中最为匹配的序列是人类类固醇生成因子-1(hSF-1),因此hSF-1可能是雷公藤内酯醇的一个潜在受体。在大肠杆菌中表达纯化了hSF-1的配体结合域(LBD),荧光光谱实验表明雷公藤内酯醇对hSF-1-LBD有荧光淬灭作用、等温滴定量热(ITC)实验表明雷公藤内酯醇与hSF-1-LBD发生焓驱动的特异性结合,表面等离子体共振(SPR)实验表明雷公藤内酯醇可以与hSF-1-LBD剂量依赖性结合,这些都证实了hSF-1与雷公藤内酯醇存在特异性相互作用。展开更多
目的探讨^(99)Tc^m 直接标记带有10个连续组氨酸的膜联蛋白 V(Annexin V)衍生物的可行性,研究其在健康小鼠体内的分布和肺癌裸鼠模型凋亡显像。方法直接标记法制备^(99)Tc^m-Annexin V 衍生物,并测产物放化纯、胶体含量及健康小鼠体内...目的探讨^(99)Tc^m 直接标记带有10个连续组氨酸的膜联蛋白 V(Annexin V)衍生物的可行性,研究其在健康小鼠体内的分布和肺癌裸鼠模型凋亡显像。方法直接标记法制备^(99)Tc^m-Annexin V 衍生物,并测产物放化纯、胶体含量及健康小鼠体内不同时间点(5,30 min 和1,2,4,6,12,24 h)的生物分布,DAS 2.0软件拟合计算药代动力学参数。建立荷 H460非小细胞肺癌裸鼠模型,分为紫杉醇诱导化疗组(5只)和未治疗对照组(5只)。紫杉醇诱导化疗后48 h,于裸鼠尾静脉注射^(99)Tc^m-Annexin V 衍生物18.5 MBq,2和4 h 时进行凋亡显像,勾画 ROI 并计算肿瘤与对侧正常组织(T/NT)放射性比值。结果放化纯达(98.01±1.67)%,3 h 后放化纯仍可达(95.45±1.34)%,胶体含量为(3.31±1.37)%。健康小鼠体内分布实验表明肾脏对该示踪剂摄取最高,肝、脾摄取较少。DAS 2.0软件拟合得到时间-放射性曲线符合二室模型特征,分布相半衰期(T_(1/2α))为(21.18±5.95)min,清除相半衰期(T_(1/2β))为(69.32±0.10)min。荷瘤鼠显像示,给药后2 h 即可获得清晰的图像,紫杉醇诱导化疗组2和4 h 的 T/NT 比值为3.85±1.10和4.63±0.97,明显高于对照组(1.60±0.29和1.71±0.43,P<0.01)。结论该Annexin V 衍生物易于^(99)Tc^m直接标记,方法简便,标记物在血液中清除迅速,肝、脾摄取少,易得到高清晰图像。展开更多
文摘A novel type of polyurethane and polyether-polyimide blends were prepared in two steps. The first step was the preparation of polyether-amic acid by the reaction of an oligmer based on polytetramethylene oxide glycol di-p-aminobenzoate (APTMO) of different molecular weight with benzenetetracarboxylic acid dianhydride (PMDA). The second step was mixing polyether-polyurethane and polyether-polyamic acid solution at room tem- perature in various weight ratios and the blend films were obtained by casting and then heating imidization .In- frared spectroscopy, dynamic mechanical analysis,differential scanning calorimetry,, wide-angle X-ray diffraction and sham-sires testing were used to study this family of blends. DMA and DSC results show that the blends exhibit a well phase-separated morphology and possess a wide range of service temperature, which varies with the PU content. The thermal stability of PU is found to increase obviously by the incorporation of PI. The excellent tensile properties of the blends suggest that they could be potentially ed as heat resistant thermoplastic elas-tomers.
文摘采用噬菌体展示肽库技术筛选雷公藤内酯醇的靶蛋白,得到了一个肽段,并通过酶联免疫吸附(ELISA)和免疫共沉淀验证了该片段对雷公藤内酯醇的结合特异性。用Basic Local Alignment Search Tool(BLAST)进行序列对比后,找到了77个匹配序列,其中最为匹配的序列是人类类固醇生成因子-1(hSF-1),因此hSF-1可能是雷公藤内酯醇的一个潜在受体。在大肠杆菌中表达纯化了hSF-1的配体结合域(LBD),荧光光谱实验表明雷公藤内酯醇对hSF-1-LBD有荧光淬灭作用、等温滴定量热(ITC)实验表明雷公藤内酯醇与hSF-1-LBD发生焓驱动的特异性结合,表面等离子体共振(SPR)实验表明雷公藤内酯醇可以与hSF-1-LBD剂量依赖性结合,这些都证实了hSF-1与雷公藤内酯醇存在特异性相互作用。
文摘目的探讨^(99)Tc^m 直接标记带有10个连续组氨酸的膜联蛋白 V(Annexin V)衍生物的可行性,研究其在健康小鼠体内的分布和肺癌裸鼠模型凋亡显像。方法直接标记法制备^(99)Tc^m-Annexin V 衍生物,并测产物放化纯、胶体含量及健康小鼠体内不同时间点(5,30 min 和1,2,4,6,12,24 h)的生物分布,DAS 2.0软件拟合计算药代动力学参数。建立荷 H460非小细胞肺癌裸鼠模型,分为紫杉醇诱导化疗组(5只)和未治疗对照组(5只)。紫杉醇诱导化疗后48 h,于裸鼠尾静脉注射^(99)Tc^m-Annexin V 衍生物18.5 MBq,2和4 h 时进行凋亡显像,勾画 ROI 并计算肿瘤与对侧正常组织(T/NT)放射性比值。结果放化纯达(98.01±1.67)%,3 h 后放化纯仍可达(95.45±1.34)%,胶体含量为(3.31±1.37)%。健康小鼠体内分布实验表明肾脏对该示踪剂摄取最高,肝、脾摄取较少。DAS 2.0软件拟合得到时间-放射性曲线符合二室模型特征,分布相半衰期(T_(1/2α))为(21.18±5.95)min,清除相半衰期(T_(1/2β))为(69.32±0.10)min。荷瘤鼠显像示,给药后2 h 即可获得清晰的图像,紫杉醇诱导化疗组2和4 h 的 T/NT 比值为3.85±1.10和4.63±0.97,明显高于对照组(1.60±0.29和1.71±0.43,P<0.01)。结论该Annexin V 衍生物易于^(99)Tc^m直接标记,方法简便,标记物在血液中清除迅速,肝、脾摄取少,易得到高清晰图像。
