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141.
142.
蛋白质糖基化是一种重要的蛋白质翻译后修饰方式,糖基化对蛋白质的结构和功能有着非常重要的影响。在血清或者组织提取液中,一些低浓度的糖蛋白/糖肽是具有高度临床灵敏性和特异性的生物标记物,这些生物分子可能对疾病发生机理探讨、疾病标记物发现及蛋白类新药开发提供重要信息。由于糖蛋白/糖肽的丰度低,从复杂的生物样品中高选择性富集糖蛋白/糖肽一直是糖蛋白组学的难点和重点。纳米结构的材料因其大比表面积、丰富的活性亲和位点和特殊结构,已经广泛应用于糖蛋白/糖肽的分离富集中。本文对基于金、SiO2、TiO2、Fe3O4、金刚石和聚合物纳米粒子为载体的糖蛋白/糖肽分离富集方法的研究进展作了简要概述,并且阐明了糖蛋白/糖肽分离富集方法所面临的挑战,最后,对其未来发展方向做了展望。 相似文献
143.
中药质量控制技术发展展望 总被引:6,自引:0,他引:6
本文从中药产业需求、现代化需求、技术需求、机遇与挑战等方面概括了中药质量控制技术发展的背景;讨论了中药质量控制技术对于提高中药药效和安全性、推动产业发展和推进中药国际化的意义;综述了中药质量控制技术的现状,分析了在过程控制、安全性控制、标准品和对照品制备、指纹图谱技术等方面的不足;提出了中药质量控制技术应重点发展以分离和表征技术为主的中药质量控制关键技术、中药安全性控制技术、中药质量控制标准体系、中药质量控制原创性技术和中药标准品、对照品生产技术,制定技术标准,建立具有中药特色的过程控制和产品质量控制标准。 相似文献
144.
Catalytic asymmetric Michael additions with curcumin derivatives were achieved by a new series of tertiary amine-thiourea organocatalysts to afford the Michael adducts in high yields and excellent enantioselectivities. 相似文献
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146.
Highly diastereo- and enantioselective one-pot Michael-Aldol reactions of α,β-unsaturated aldehydes with imidazole derivatives have been developed. The cascade reactions products could be obtained with three stereocenters in high yields and excellent diastereo- and enantioselectivities. 相似文献
147.
A novel zwitterionic stationary phase with high hydrophilicity was facilely synthesized based on the "thiol-ene" click reaction between cysteine and vinyl silica, which exhibited great potential in the separation of oligosaccharides, peptides and basic compounds, as well as in the enrichment of glycopeptides. 相似文献
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149.
The conjugate addition of Ni(II) complexes of glycine Schiff base to α,β-unsaturated aldehydes catalyzed by (S)-2-(diphenyl(trimethylsilyloxy)methyl)pyrrolidine afforded adducts in excellent yields with up to 49:1 dr and 95% ee. This method enables the construction of two adjacent chiral centers in one step, and offers an alternative route to chiral α-amino acid derivatives. 相似文献
150.
Capture columns are important interface tools for on line two-dimensional liquid chromatography (2D-LC). In this study, a systematic method was developed to evaluate and optimize the capture ability of capture columns by off-line method. First, the parameter ΔtR (ΔtR = t2−t1−t0−W) was introduced to quantitatively represent the capture ability of the capture column by connecting a capture column behind the first dimensional column. Based on the value of ΔtR, an appropriate capture column was selected after the first dimensional column was fixed. Then, the capture ability of the selected column was promoted by adjusting the mobile phase of the first dimensional column. Capture ability was also optimized using complex sample analysis software system (CSASS) software. Second, the elution mode of the trapped compounds on the capture column was investigated by connecting the capture column before the second dimensional column. More specifically, in mode I, capture column was connected to the second dimension without changing the flow rate direction and the trapped compounds must pass through the capture column and be eluted into the second dimensional column. The contrary connection mode was mode II. It was found that mode I is more suitable method for 2D-LC. Finally, an off-line reversed-phase/hydrophilic interaction liquid chromatography two-dimensional liquid chromatography (RP/HILIC 2D-LC) system with a C18 capture column was developed to demonstrate the practical application of this method. 相似文献