气相色谱法测定人红细胞膜脂肪酸的组成及含量

取正常人和阵发睡眠血红蛋白尿症患者(PNH)的全血2毫升,分离提取全血中红细胞膜脂类物质,用碱催化法将脂质中的脂肪酸转为其甲酯,并进行气相色谱分析,经GC-MS鉴定表明人的红细胞膜的肪酸主要是C_(16:0),C_(18:0),C_(18:1),C_(18:2),C_(20:4)。采用相对重量响应因子一归一化法定量。结果说明PNH患者的红细胞膜脂的组成是不正常的。膜脂肪酸不饱和度增大会引起抗氧化能力的下降和膜流动性增大,这些都是造成溶血的因素。为研究膜异常和疾病的关系提供依据。     

Structural biology revolution led by technical breakthroughs in cryo-electron microscopy

Recent technical breakthroughs in cryo-electron microscopy(cryo-EM) revolutionized structural biology, which led to the 2017 Nobel Prize in chemistry being awarded to three scientists, Jacques Dubochet, Joachim Frank, and Richard Henderson, who made groundbreaking contributions to the development of cryo-EM. In this review, I will give a comprehensive review of the developmental history of cryo-EM, the technical aspects of the breakthrough in cryo-EM leading to the structural biology revolution, including electron microscopy, image recording devices and image processing algorithms,and the major scientific achievements by Chinese researchers employing cryo-EM, covering protein complexes involved in or related to gene expression and regulation, protein synthesis and degradation, membrane proteins, immunity, and viruses.Finally, I will give a perspective outlook on the development of cryo-EM in the future.     

二维核磁共振谱及其应用—同核位移相关谱

自70年代末期以来,由于二维核磁共振谱的迅速发展,核磁共振波谱学发展到一个新的时期。核磁共振成为有机化合物结构鉴定的更有效方法。二维核共振谱可分为三大类:位移相关谱、J分辨谱和多量子二维谱。本文将选择最常