^(23)Na is a nuclear magnetic resonance(NMR)-active isotope with a nuclear spin quantum number of 3/2.^(23)Na relaxation phenomenon is at the core of ^(23)Na NMR measurement and analysis.Due to the dominance of quadru...^(23)Na is a nuclear magnetic resonance(NMR)-active isotope with a nuclear spin quantum number of 3/2.^(23)Na relaxation phenomenon is at the core of ^(23)Na NMR measurement and analysis.Due to the dominance of quadrupolar interaction,the relaxation behavior of ^(23)Na is physically and mathematically more complex than that of a typical spin-1/2 isotope.In this review,we overview the semi-classical Redfield theory for deriving the formulations of ^(23)Na relaxation.We show that the relaxation behaviors of ^(23)Na can be quantitatively described by constructing the spectral density functions based on the second-order perturbation theory.In addition,we summarize the applications of ^(23)Na relaxometry in different research fields,including biomedicine,sodium ion batteries,and quantum information processing.Because sodium is an essential element in our body,food and industrial materials,the research on sodium by ^(23)Na NMR emerges as important future directions.The theoretical and practical understandings on ^(23)Na relaxation are the step stones for mastering advanced ^(23)Na NMR techniques.展开更多
目的通过研究慢性B淋巴细胞白血病（chronic B cell lymphocytic leukemia，B—CLL）CD4^＋CD25^＋highCDl27^Low和CD19^＋CD23^＋的相关性，探讨CD4^＋CD25^＋highCDl27^Low在B—CLL发生发展过程中的作用。方法将20例初次发病的B—CLL...目的通过研究慢性B淋巴细胞白血病（chronic B cell lymphocytic leukemia，B—CLL）CD4^＋CD25^＋highCDl27^Low和CD19^＋CD23^＋的相关性，探讨CD4^＋CD25^＋highCDl27^Low在B—CLL发生发展过程中的作用。方法将20例初次发病的B—CLL患者按临床分期的不同分为O-II期组、III-IV期组，设立正常对照组，应用流式细胞仪检测各组的研究对象外周血中CD4^＋CD25^＋highCDl27^Low、CD19^＋、CD19^＋CD23^＋的表达量，比较各组间的差异。结果B—CLL O-II期组、III-IV期组患者外周血中CD4^＋CD25^＋highCDl27^Low、CD19^＋、CD19^＋CD23^＋的表达量均明显高于正常对照组；B—CLL患者III-IV期组的CD4^＋CD25^＋highCDl27^Low、CDl9^＋、CDl9^＋CD23^＋表达量明显高于O-II期组；CD4^＋CD25^＋highCDl27^Low、CDl9^＋CD23^＋有明显的正相关性。结论B—CLL患者外周血中CD4^＋CD25^＋highCD127^Low的表达量增高，与CD19^＋、CD19^＋CD23^＋的表达量增高明显相关，可能是B—CLL患者CD19^＋CD23^＋克隆性增生原因之一．展开更多
Bile acids are the main body of enterohepatic circulation in vivo.They have essential functions such as emulsifying fat,bacteriostasis and regulating multiple metabolic pathways as signal molecules.However,the assignm...Bile acids are the main body of enterohepatic circulation in vivo.They have essential functions such as emulsifying fat,bacteriostasis and regulating multiple metabolic pathways as signal molecules.However,the assignments of NMR signals for some lowconcentration bile acids are still needed.This study combined 1D nuclear magnetic resonance(NMR)and 2D NMR techniques including 1He1H correlation spectroscopy(COSY),1He1H total correlation spectroscopy(TOCSY),1H J-resolved spectroscopy(J-Res),1He13C heteronuclear single quantum coherence spectroscopy(HSQC),and 1He13C heteronuclear multiple bond correlation spectroscopy(HMBC)to assign the 1H and 13C signals of six bile acids in aqueous solution at physiological pH(~7.4)and nine bile acids in methanol.These data are of importance to the NMR-based studies on lipid digestion,absorption,and metabolism.展开更多
基金National Natural Science Foundation of China 22275159 and 22072133.Leading Innovation and Entrepreneurship Team of Zhejiang Province 2020R01003.
文摘^(23)Na is a nuclear magnetic resonance(NMR)-active isotope with a nuclear spin quantum number of 3/2.^(23)Na relaxation phenomenon is at the core of ^(23)Na NMR measurement and analysis.Due to the dominance of quadrupolar interaction,the relaxation behavior of ^(23)Na is physically and mathematically more complex than that of a typical spin-1/2 isotope.In this review,we overview the semi-classical Redfield theory for deriving the formulations of ^(23)Na relaxation.We show that the relaxation behaviors of ^(23)Na can be quantitatively described by constructing the spectral density functions based on the second-order perturbation theory.In addition,we summarize the applications of ^(23)Na relaxometry in different research fields,including biomedicine,sodium ion batteries,and quantum information processing.Because sodium is an essential element in our body,food and industrial materials,the research on sodium by ^(23)Na NMR emerges as important future directions.The theoretical and practical understandings on ^(23)Na relaxation are the step stones for mastering advanced ^(23)Na NMR techniques.
文摘Bile acids are the main body of enterohepatic circulation in vivo.They have essential functions such as emulsifying fat,bacteriostasis and regulating multiple metabolic pathways as signal molecules.However,the assignments of NMR signals for some lowconcentration bile acids are still needed.This study combined 1D nuclear magnetic resonance(NMR)and 2D NMR techniques including 1He1H correlation spectroscopy(COSY),1He1H total correlation spectroscopy(TOCSY),1H J-resolved spectroscopy(J-Res),1He13C heteronuclear single quantum coherence spectroscopy(HSQC),and 1He13C heteronuclear multiple bond correlation spectroscopy(HMBC)to assign the 1H and 13C signals of six bile acids in aqueous solution at physiological pH(~7.4)and nine bile acids in methanol.These data are of importance to the NMR-based studies on lipid digestion,absorption,and metabolism.
