A highly sensitive stopped-flow spectrophotometry kinetic method was proposed for quantification phenoxyl radicals based on their accelerating effect on the oxidation of nicotinamide adenine dinucleotide （NADH）. Phe...A highly sensitive stopped-flow spectrophotometry kinetic method was proposed for quantification phenoxyl radicals based on their accelerating effect on the oxidation of nicotinamide adenine dinucleotide （NADH）. Phenoxyl radicals generated from as low as 1×10^-8 mol/L 2,4-DCP can be readily detected with the proposed method and the detecting limit was 2.5×10^-9 mol/L.展开更多
1-Imino nitroxide pyrene 1 has been characterized as a H^＋ fluorescent switch. The effects of various interfering species, solvents and the irradiation of ultraviolet light on the fluorescence intensity of 1 are also...1-Imino nitroxide pyrene 1 has been characterized as a H^＋ fluorescent switch. The effects of various interfering species, solvents and the irradiation of ultraviolet light on the fluorescence intensity of 1 are also investigated. 1 fluoresces weakly in the 85% ethanol media containing no more than 4.5x10-5 mol/L of H^＋ （HCI）, but can produce a burst increase of about 4 times in the fluorescence intensity when the concentration of H＋ is increased to or over 4.9×10^-5mol/L. The extremely sharp response of 1 to H＋ occurs only within such a narrow concentration range. Moreover, the decrease of H^＋ concentration through adding sodium hydroxide causes the fluorescence quenching, suggesting that 1 may serve as a fluorescent switch for monitoring the concentration change of H＋ around the point of 4.5×10^-5 mol/L.展开更多
In this paper, chiral discrimination in N-(O,O-dialkyl)phosphoamino acid monolayers at the air/water interface was studied and it was revealed that the D:L=1:1 racemic monolayer of N-(O, O-dihexadecyl)phosphoalanine i...In this paper, chiral discrimination in N-(O,O-dialkyl)phosphoamino acid monolayers at the air/water interface was studied and it was revealed that the D:L=1:1 racemic monolayer of N-(O, O-dihexadecyl)phosphoalanine is packed more densely in solid phase while shows a higher LE to LC transition pressure than the enantiomeric ones.展开更多
To investigate the HLA-A, -B allele polymorphism in Han population of Shandong province and to explore the possibility to find out the HLA-A, -B-matched cord blood donors for stem cell transplantation to be used in ot...To investigate the HLA-A, -B allele polymorphism in Han population of Shandong province and to explore the possibility to find out the HLA-A, -B-matched cord blood donors for stem cell transplantation to be used in other area in China, 5844 umbilical cord blood samples were taken from Han population donors of Shandong province, and assayed with PCR-sequence-oligonucleotide (PCR-SSO) assay. In Shandong Han donors, 20 alleles at HLA-A locus and 46 alleles at HLA-B locus could be detected as revealed in the present study. Among the 20 alleles at HLA-A locus, the most prevalent five alleles included A * 02(0.3041), A * 11(0.1443), A * 24(0.1434), A * 30(0.0975) and A * 33(0.0859), while, the alleles with lower gene frequencies included A * 34(0.0006), A * 25 (0.0005), A*66(0.0005), A* 74(0.0004) and A* (0.0001). Of the 46 HLA-B alleles detected, the most prevalent five alleles were B * 13(0.1348), B * 51(0.0713), B * 62(0.0712), B * 61 (0.0676) and B * 60(0.0642); while alleles with lower gene frequencies included B * 77(0.0001), B * 76(0.0002), B * 47(0.0003), B * 42(0.0003) and B * 72(0.0004). In comparison with those of the other Han population in China, the HLA-A, -B gene frequencies in the umbilical cord blood of Shandong province possess unique distribution features among the investigated populations from various regions of the same race origin, and the differences in various regions of the same race were less than those among the different race. It is evident that the HLA-A,-B alleles of the umbilical cord blood taken in Shangdong province show high degree of polymorphism, and it might be part of those of Northern Han population in China. So, it is reasonable for patients of Northern Chinese to receive HLA class I -match transplant of cord blood stem cells for tissue and organ transplantation from Shangdong umbilical cord blood bank.展开更多
基金The authors gratefully acknowledge financial support from the National Natural Science Foundation of China （No. 20275027 and No. 20377032）.
文摘A highly sensitive stopped-flow spectrophotometry kinetic method was proposed for quantification phenoxyl radicals based on their accelerating effect on the oxidation of nicotinamide adenine dinucleotide （NADH）. Phenoxyl radicals generated from as low as 1×10^-8 mol/L 2,4-DCP can be readily detected with the proposed method and the detecting limit was 2.5×10^-9 mol/L.
基金Financial support from the NNSF of China(Nos.20375044 and 20435030)the Chinese Academy of Sciences(KJCX2-SW-H06)is acknowledged.
文摘1-Imino nitroxide pyrene 1 has been characterized as a H^＋ fluorescent switch. The effects of various interfering species, solvents and the irradiation of ultraviolet light on the fluorescence intensity of 1 are also investigated. 1 fluoresces weakly in the 85% ethanol media containing no more than 4.5x10-5 mol/L of H^＋ （HCI）, but can produce a burst increase of about 4 times in the fluorescence intensity when the concentration of H＋ is increased to or over 4.9×10^-5mol/L. The extremely sharp response of 1 to H＋ occurs only within such a narrow concentration range. Moreover, the decrease of H^＋ concentration through adding sodium hydroxide causes the fluorescence quenching, suggesting that 1 may serve as a fluorescent switch for monitoring the concentration change of H＋ around the point of 4.5×10^-5 mol/L.
文摘In this paper, chiral discrimination in N-(O,O-dialkyl)phosphoamino acid monolayers at the air/water interface was studied and it was revealed that the D:L=1:1 racemic monolayer of N-(O, O-dihexadecyl)phosphoalanine is packed more densely in solid phase while shows a higher LE to LC transition pressure than the enantiomeric ones.
文摘To investigate the HLA-A, -B allele polymorphism in Han population of Shandong province and to explore the possibility to find out the HLA-A, -B-matched cord blood donors for stem cell transplantation to be used in other area in China, 5844 umbilical cord blood samples were taken from Han population donors of Shandong province, and assayed with PCR-sequence-oligonucleotide (PCR-SSO) assay. In Shandong Han donors, 20 alleles at HLA-A locus and 46 alleles at HLA-B locus could be detected as revealed in the present study. Among the 20 alleles at HLA-A locus, the most prevalent five alleles included A * 02(0.3041), A * 11(0.1443), A * 24(0.1434), A * 30(0.0975) and A * 33(0.0859), while, the alleles with lower gene frequencies included A * 34(0.0006), A * 25 (0.0005), A*66(0.0005), A* 74(0.0004) and A* (0.0001). Of the 46 HLA-B alleles detected, the most prevalent five alleles were B * 13(0.1348), B * 51(0.0713), B * 62(0.0712), B * 61 (0.0676) and B * 60(0.0642); while alleles with lower gene frequencies included B * 77(0.0001), B * 76(0.0002), B * 47(0.0003), B * 42(0.0003) and B * 72(0.0004). In comparison with those of the other Han population in China, the HLA-A, -B gene frequencies in the umbilical cord blood of Shandong province possess unique distribution features among the investigated populations from various regions of the same race origin, and the differences in various regions of the same race were less than those among the different race. It is evident that the HLA-A,-B alleles of the umbilical cord blood taken in Shangdong province show high degree of polymorphism, and it might be part of those of Northern Han population in China. So, it is reasonable for patients of Northern Chinese to receive HLA class I -match transplant of cord blood stem cells for tissue and organ transplantation from Shangdong umbilical cord blood bank.
