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Diagnostic value of methylated branched chain amino acid transaminase 1/IKAROS family zinc finger 1 for colorectal cancer 被引量:1
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作者 Ke Xu Ai-Ru Yu +1 位作者 Shen-Bin Pan Jie He 《World Journal of Gastroenterology》 SCIE CAS 2023年第36期5240-5253,共14页
BACKGROUND The diagnostic value of combined methylated branched chain amino acid transaminase 1(BCAT1)/IKAROS family zinc finger 1(IKZF1)in plasma for colorectal cancer(CRC)has been explored since 2015.Recently,severa... BACKGROUND The diagnostic value of combined methylated branched chain amino acid transaminase 1(BCAT1)/IKAROS family zinc finger 1(IKZF1)in plasma for colorectal cancer(CRC)has been explored since 2015.Recently,several related studies have published their results and showed its diagnostic efficacy.AIM To analyze the diagnostic value of methylated BCAT1/IKZF1 in plasma for screening and postoperative follow-up of CRC.METHODS The candidate studies were identified by searching the PubMed,Embase,Cochrane Library,CNKI,and Wanfang databases from May 31,2003 to June 1,2023.Sensitivity,specificity,and diagnostic accuracy were calculated by merging ratios or means.RESULTS Twelve eligible studies were included in the analysis,involving 6561 participants.The sensitivity of methylated BCAT1/IKZF1 in plasma for CRC diagnosis was 60%[95%confidence interval(CI)53-67]and specificity was 92%(95%CI:90-94).The positive and negative likelihood ratios were 8.0(95%CI:5.8-11.0)and 0.43(95%CI:0.36-0.52),respectively.Diagnostic odds ratio was 19(95%CI:11-30)and area under the curve was 0.88(95%CI:0.85-0.91).The sensitivity and specificity for CRC screening were 64%(95%CI:59-69)and 92%(95%CI:91-93),respectively.The sensitivity and specificity for recurrence detection during follow-up were 54%CONCLUSION The detection of methylated BCAT1/IKZF1 in plasma,as a non-invasive detection method of circulating tumor DNA,has potential CRC diagnosis,but the clinical application prospect needs to be further explored. 展开更多
关键词 Branched chain amino acid transaminase 1 IKAROS family zinc finger 1 methylATION Liquid biopsy Colorectal cancer
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Comparative Studies on Degradation of Methyl Orange by Nanostructured Zinc and Zinc Oxide Films
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作者 吴炳俊 郝常山 +1 位作者 谢斌 李明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期615-620,622,共7页
Nanostructured zinc and zinc oxide films were prepared by magnetron sputtering processes and succeeded air annealing treatments. Comparison of reductive degradation rate of methyl orange (MO) by zinc films and photo... Nanostructured zinc and zinc oxide films were prepared by magnetron sputtering processes and succeeded air annealing treatments. Comparison of reductive degradation rate of methyl orange (MO) by zinc films and photocatalytic degradation rate of MO by zinc oxide films was carried out. Both reductive degradation and photocatalytic degradation process of MO by zinc and zinc oxide films can be described by first order kinetic model. It was found that although MO liquid was most quickly decolorized by metallic zinc films, the mineraliza- tion of MO was not thorough. Observation of extra ultraviolet absorption peaks indicated the formation of aromatic intermediates. On the other hand, although the photocatalytic degradation rate of MO liquid by ZnO films was only as about 1/4 large as the reductive degradation rate by zinc films, no signs of aromatic intermediates were found. Moreover, it was found that partially oxidized zinc oxide film showed higher photocatalytic efficiency than the totally oxidized ZnO films. Synergy effect between zinc and zinc oxide phase in the partially oxidized films was considered to be responsible for the higher photocatalytic efficiency. 展开更多
关键词 methyl orange zinc ZnOx ZNO Reductive degradation PHOTOCATALYSIS
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Visible Light-induced Photoluminescence of a Zinc(Ⅱ) Complex of N-methyl-4,4-bipyridinium Cation
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作者 DU Ming-Xiu YANG Chen +1 位作者 CAI Li-Zhen GUO Guo-Cong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第2期317-324,169,共9页
Compounds with visible-light-induced photoluminescence are particularly attractive in acting as the emitting components of light-emitting diodes and fluorescent probes for biological applications. A new complex [Zn(NC... Compounds with visible-light-induced photoluminescence are particularly attractive in acting as the emitting components of light-emitting diodes and fluorescent probes for biological applications. A new complex [Zn(NCS)_3(MQ)](MQ^+ = N-methyl-4,4?-bipyridinium) with an isolated molecular structure has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and solid-state photoluminescent determination. Crystal data: C_(14)H_(11)N_5S_3Zn, M_r = 410.83, monoclinic, space group P2_1/c, a = 8.809(5), b = 13.138(7), c = 15.580(9) ?, b = 104.433(10)°, V = 1746.2(17) ?~3, Z = 4, D–c = 1.563 g×cm^3, μ = 1.769 mm^(–1), F(000) = 832, the final R = 0.0376 and wR = 0.1243 for 2850 observed reflections with I > 2s(I). In the crystal structure, the zinc atom is tetrahedrally coordinated by one MQ+ ligand and three NCS– groups to yield a tetrahedral configuration. The bond length of Zn–NMQ is clearly shorter than those found in reported Zn(Ⅱ) complexes of 4,4?-bipy. The isolated units are joined by C–H···S interactions to generate a 2D hydrogen-bonding network. This compound displays visible light-induced photoluminescence, which originates from both intraligand charge-transfer of the MQ+ ligand and NCS~–→MQ^+ charge-transfer according to a density of states(DOS) calculation. Moreover, its emission band shows a clear blue shift compared with those of halide compounds. 展开更多
关键词 zinc COMPLEX N-methyl-4 4-bipyridinium PHOTOLUMINESCENCE visible-light excitation
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A Hydrogen-bonded Tubular Structure of Zinc(Ⅱ) and Methyl-3-pyridylcarbamate
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作者 夏娅娜 李少光 +1 位作者 龙泽荣 吴彪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第6期875-878,共4页
A zinc(Ⅱ) compound [ZnCl2(mpcm)2](1,mpcm = methyl-3-pyridylcarbamate) was prepared by solvothermal reaction and characterized by elemental analysis,IR spectroscopy,TGA and single-crystal X-ray diffraction.The c... A zinc(Ⅱ) compound [ZnCl2(mpcm)2](1,mpcm = methyl-3-pyridylcarbamate) was prepared by solvothermal reaction and characterized by elemental analysis,IR spectroscopy,TGA and single-crystal X-ray diffraction.The crystal is of monoclinic system,space group P21/n,C14H16ZnCl2N4O4,Mr = 440.58,a = 8.7893(7),b = 24.978(2),c = 9.2510(8),β = 109.318(1)°,V = 1916.6(3)3,Z = 4,θ = 1.63~25.20°,Dc = 1.527 g/cm3,μ = 1.585 mm-1,F(000) = 896,the final R = 0.0255 and wR = 0.0654 for 3080 observed reflections with Ⅰ 〉 2σ(Ⅰ).The zinc atom is four-coordinated by the pyridyl groups of two mpcm ligands and two chloride ions with a tetrahedral geometry.Two [ZnCl2(mpcm)2] subunits are held together by a pair of hydrogen bonds,forming a 32-membered macrocyclic dimer,which is further extended into a 3D tubular structure via hydrogen bonding. 展开更多
关键词 zinc methyl-3-pyridylcarbamate hydrogen-bonded tubular structure
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Synthesis and Structure of Zinc Complex of N, N-bis ( benzimidazol-2-yl-methyl ) amine
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作者 Xiao Lan LIU Qing Yan CHENG +3 位作者 Xia YANG Zhi Wei MIAO Wei LIU Fang Ming MIAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期563-564,共2页
The Zinc complex of N, N-bis (benzimidazol 2-yl-methy])amine has been synthesized and its crystal structure determined by X-ray diffraction method. The structure features of the complex are described.
关键词 zinc compex N N-bis (benzimidazol-2-yl-methyl)amine superoxide dismutase (SOD)
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用于可见光降解甲基橙的ZnIn_(2)S_(4)/CaIn_(2)S_(4)光催化剂性能
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作者 杨方玉 董晓丽 +1 位作者 郑楠 王宇 《大连工业大学学报》 CAS 2024年第1期26-30,共5页
采用一步水热法构建了ZnIn_(2)S_(4)/CaIn_(2)S_(4)(ZIS/CIS)异质结光催化剂。通过XRD、SEM、DRS、电化学测试等表征研究此异质结光催化剂的晶体结构、形貌、光学性质及光生载流子的分离效率,在模拟可见光下考察其对甲基橙的降解效率。... 采用一步水热法构建了ZnIn_(2)S_(4)/CaIn_(2)S_(4)(ZIS/CIS)异质结光催化剂。通过XRD、SEM、DRS、电化学测试等表征研究此异质结光催化剂的晶体结构、形貌、光学性质及光生载流子的分离效率,在模拟可见光下考察其对甲基橙的降解效率。实验结果表明,ZIS/CIS异质结材料对甲基橙的降解效果明显优于CIS和ZIS。ZIS摩尔分数为30%的复合样品具有最佳的甲基橙降解效率,60 min内达到95.54%,并且具有良好的稳定性。 展开更多
关键词 异质结 光催化剂 硫铟钙 硫铟锌 甲基橙
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催化热分解法制备含P-C键多元异氰酸酯的研究
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作者 花胜权 王瑞 +3 位作者 邵悦纳 张玉松 胡盛 谭志伟 《化学与生物工程》 CAS 北大核心 2024年第3期27-33,共7页
以二(N-甲氧羰基氨甲基)苄基氧化膦(BCBPO)和三(N-甲氧羰基氨甲基)氧化膦(TCPO)为原料,采用热重法筛选了热分解催化剂,通过催化热分解法制备了含P-C键多元异氰酸酯,并分别采用TG-GC-MS联用法和变温红外光谱法分析了催化热分解BCBPO和TCP... 以二(N-甲氧羰基氨甲基)苄基氧化膦(BCBPO)和三(N-甲氧羰基氨甲基)氧化膦(TCPO)为原料,采用热重法筛选了热分解催化剂,通过催化热分解法制备了含P-C键多元异氰酸酯,并分别采用TG-GC-MS联用法和变温红外光谱法分析了催化热分解BCBPO和TCPO的气态产物和凝聚态产物。结果表明,相对于直接热分解,氧化锌为催化剂热分解BCBPO和TCPO的热分解温度分别降低了29℃和25℃;BCBPO、TCPO在氧化锌催化作用下第一阶段热分解的气态产物为甲醇、凝聚态产物为异氰酸酯;红外光谱分析结果显示,在氧化锌催化作用下,TCPO热分解的凝聚态产物与苯胺反应的固体产物为相应异氰酸酯TPI与苯胺反应的产物脲。 展开更多
关键词 含磷氨基甲酸甲酯 含磷多元异氰酸酯 催化热分解 反应型含磷阻燃剂 氧化锌
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Silencing SMYD3 in hepatoma demethylates RIZI promoter induces apoptosis and inhibits cell proliferation and migration 被引量:21
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作者 Li-Bo Chen Jun-Yao Xu +1 位作者 Zhen Yang Guo-Bin Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第43期5718-5724,共7页
AIM: To investigate the role of SMYD3 in hepatocellular carcinoma (HCC) development and progression and to verify whether its regulation activity was through RIZ1 inactivation. METHODS: Expression of SMYD3 in HCC ... AIM: To investigate the role of SMYD3 in hepatocellular carcinoma (HCC) development and progression and to verify whether its regulation activity was through RIZ1 inactivation. METHODS: Expression of SMYD3 in HCC cell lines and tissues were measured; silencing of SMYD3 by RNA interference (RNAi) was effectuated, hepatoma cell proliferation, migration and apoptosis were tested, with RIZl CpG promoter methylation, and corresponding mRNA expression were investigated. RESULTS: SMYD3 over-expression in HCC was associated with RIZl hypermethylation and mRNA down-expression. Suppression of SMYD3 expression de- methylated RIZl CpG promoter (P 〈 0.01) and increased RIZl mRNA expression (P 〈 0.01). Consequently, SMYD3 down-expression with RIZl de-methylation strongly inhibited hepatoma cell growth (MTT inhibitory rates: Pgenesil-1-s1 60.95%± 7.97%, Pgenesil-1-s2 72.14% ± 9.68% vs Pgenesil-1-hk 6.89% ± 4.12%, P 〈 0.01) and migration (Pgenesil-1-s1 4.24% ± 1.58%, Pgenesil- 1-s1 4.87% ± 0.73% vs Pgenesil-1 19.03% ± 4.63%, Pgenesil-1-hk 19.95% ±5.21%, P 〈 0.01) and induced apoptosis (FCM subG1 phase Pgenesil-1-s1 19.07% + 1.78%, Pgenesil-1-s2 17.68% ± 2.36% vs Pgenesil-1 0.47% ± 0.12%, Pgenesil-1-hk 1.46% ± 0.28%, P 〈 0.01. TUNEL-positive cells: Pgenesil-1-s1 40.24%± 5.18%, Pgenesil-1-s2 38.48% ± 4.65% vs Pgenesil-1 2.1B% - 1.34%, Pgenesil-1-hk 2.84%± 1.22%, P 〈 0.01) in HepG2 cells. CONCLUSION: These results demonstrate that SMYD3plays a critical role in the carcinogenesis and progression of HCC, The proliferation, migration induction and apoptosis inhibition activities of SMYD3 may be mediated through RIZl CpG promoter hypermethylation. 展开更多
关键词 SMYD3 Hepatocellular carcinoma Retinoblastoma protein-interacting zinc finger gene Histone methyltransferase DNA methylation
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Study on RIZ1 gene promoter methylation status in human esophageal squamous cell carcinoma 被引量:6
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作者 Shang-Wen Dong Peng Zhang +6 位作者 Yi-Mei Liu Yuan-Tao Cui Shuo Wang Shao-Jie Liang Zhun He Pei Sun Yuan-Guo Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第6期576-582,共7页
AIM: To investigate the promoter region methylation status of retinoblastoma protein-interacting zinc finger gene 1 (RIZ1) in the human esophageal squamous cell carcinoma (ESCC) cell lines and tissues and verify ... AIM: To investigate the promoter region methylation status of retinoblastoma protein-interacting zinc finger gene 1 (RIZ1) in the human esophageal squamous cell carcinoma (ESCC) cell lines and tissues and verify the relationship between methylation of RIZ1 and oncogen- esis, tumor progression and metastasis etc of ESCC. METHODS: Methylation-specific polymerase chain reac- tion (MSP) was used to investigate the promoter region methylation status of RIZ1 in 6 ESCC cell lines. One cell line where RIZ1 promoter region methylation was de- tected was selected for the next study, where the cell line was treated with 5-aza-CdR. Real-time polymerase chain reaction was used to investigate its influence on the transcription of RIZ1. Experiments using frozenpathological specimens from 47 ESCC patients were performed using the same MSP methodology. RESULTS: Promoter methylation of RIZ1 gene was detected in TEl3, CaEs17 and EC109 cell lines and the cell line TEl3 was chosen for further study. The expression of RIZl mRNA in TE-13 was up-regulated after treatment with 5-aza-CdR. The rate of methyla- tion in carcinomas tissues was significantly higher than those in matched neighboring normal and distal ending normal tissue, and the deviation of data was statisti- cally significant (2,2 = 24.136, P 〈 0.01). Analysis of the gender, age familial history, tumour deviation, tumour saturation, lymph gland displacement and clinical stag- ing of 47 samples from ESCC patients showed that the fluctuation of data was not statistically significant. CONCLUSION: Promoter methylation may play an im- portant role in the epigenetic silencing of RIZ1 gene expression in human ESCC. RIZ1 is considered to be a potential tumor suppressor gene and may be a biologi- cal parameter for testing early stage human ESCC. 展开更多
关键词 Retinoblastoma protein-interacting zinc fingergene 1 Tumor suppressor genes Esophageal squamouscell carcinoma Promoter methylation methylation-spe-cific polymerase chain reaction
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Construction of a New(4,8)-Connected Coordination Polymer Based on the Zinc Cluster:Structure,Topology,and Luminescence 被引量:1
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作者 安燕燕 卢丽萍 朱苗力 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第9期1479-1485,共7页
The title complex, [Zn3(L)2(H2 O)2]n(1, H3 L = 5-((3-formylphenoxy)methyl)isophthalic acid), has been synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffract... The title complex, [Zn3(L)2(H2 O)2]n(1, H3 L = 5-((3-formylphenoxy)methyl)isophthalic acid), has been synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction, IR spectroscopy and thermogravimetric analysis. Compound 1 exhibits a 3D binodal(4,8)-connected net based on trinuclear [Zn3(COO)4] clusters with the topology symbol of(416·612)(44·62)2. It crystallizes in monoclinic system, space group P21/c, with a = 13.548(3), b = 13.291(3), c = 8.2750(1) ?, β = 97.08(3)°, V = 1478.7(6) ?3, Z = 2, Mr = 858.6 g/mol, Dc = 1.928 mg/m3, μ = 2.49 mm-1, F(000) = 864, GOOF = 1.12, the final R = 0.0457 and wR = 0.1329 for 4334 observed reflections with I 〉 2σ(I). Additionally, the photoluminescent behaviours of 1 and H3 L have also been investigated in the solid state at room temperature. 展开更多
关键词 5-((3-formylphenoxy)methyl)isophthalic acid zinc(Ⅱ) compound crystal structure luminescent property
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Synthesis and Crystal Structure of Dinuclear Zinc(II) Complex with 3-Me-N-oxopyridine-2-thiol 被引量:1
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作者 牛德仲 孙柏旺 +1 位作者 路再生 宋保林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第2期108-111,共4页
The complex Zn(Mept) 2 (Mept=Bis(3-methyl-oxopyridine-2-thionato)) was obtained by the reaction of MeHpt with ZnSO 4 in ethanol. A single crystal X-ray study shows that the complex bis(3-Me-oxopyridine-2-thionato)zi... The complex Zn(Mept) 2 (Mept=Bis(3-methyl-oxopyridine-2-thionato)) was obtained by the reaction of MeHpt with ZnSO 4 in ethanol. A single crystal X-ray study shows that the complex bis(3-Me-oxopyridine-2-thionato)zinc(II) (Zn 2C 24 H 24 N 4O 4S 4) is a dimer. The oxygen and sulfur atoms from Mept ligand coordinates to a zinc atom forming (3-Me-oxopyridine-2-thionato)zinc(II) monomer, and every two monomeric units are linked centrosymmetrically by two oxygen bridges. The compound Zn(Mept) 2 belongs to the monoclinic system with space group P2 1/c, a=7.7627(9), b = 10.3335(7), c=17.4528(13) , β=99.134(9)°, V=1382.2(2) 3, Z=2, M r=691.46, D c=1.661 g/cm 3, μ=2.076 mm -1 , F(000)=704, R=0\^0463, R w=0.0747 for 3378 reflections with I>2σ(I). The coordination geometry about each Zn(II) ion is a distorted trigonal bipyramid. The Zn atom is coordinated by two sulfur atoms (Zn(1)-S(1) 2.307(1); Zn(1)-S(2) 2.295(2)) and one oxygen atom (Zn-O(2A) 2.126(3)) in the equatorial plane, while the two oxygen atoms of Mept ligands (Zn(1)-O(1) 2\^050(3), Zn(1)-O(2) 2\^172(3)) occupy the axial positions with O(1)-Zn(1)-O(2) 177\^2(1)°. 展开更多
关键词 crystal structure zinc COMPLEX 3-methyl-oxopyridine-2-thione
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石墨炉原子吸收法测定湿法炼锌含锌中间物料中铊含量
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作者 金忠 高品芳 +3 位作者 张昱琛 巩燕飞 卓劼君 李彦龙 《中国有色冶金》 CAS 北大核心 2023年第3期34-40,共7页
铊及其化合物有剧毒,在湿法炼锌工艺生产过程中存在环境污染风险,但是湿法炼锌过程中间物料中铊的存在形态复杂,含量低且不稳定,造成湿法炼锌过程含铊中间物料中铊的跟踪监测与检测较为困难。本文利用铁盐及硫酸-溴化钾萃取富集消除复... 铊及其化合物有剧毒,在湿法炼锌工艺生产过程中存在环境污染风险,但是湿法炼锌过程中间物料中铊的存在形态复杂,含量低且不稳定,造成湿法炼锌过程含铊中间物料中铊的跟踪监测与检测较为困难。本文利用铁盐及硫酸-溴化钾萃取富集消除复杂基体成分对铊测定的干扰,使Tl^(3+)与Br^(-)形成的[TlBr_(4)]^(-)配阴离子被甲基异丁基甲酮(MIBK)定量萃取后形成离子配合物,进行有机相中铊的测定。通过优化仪器测定条件,确定石墨炉灰化温度400℃,原子化温度1650℃,从而实现对锌冶炼工艺含锌中间物料中铊元素含量的准确测定。方法的检出限为0.27μg/L,RSD<10%,加标回收率为95.2%~102.6%,分析结果经与ICP-MS检测数据对比,结果准确可靠。 展开更多
关键词 石墨炉原子吸收法 湿法炼锌 检测 硫酸-溴化钾介质 甲基异丁基甲酮 萃取 回收率
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缺锌对经MNNG诱导的HEEC氧化应激和甲基化的影响
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作者 黄淑翠 张慧霞 +1 位作者 党兴波 韩菲 《现代医药卫生》 2023年第6期901-906,共6页
目的探讨缺锌对经N-甲基-N′-硝基-N-亚硝基胍(MNNG)诱导的人正常食管上皮细胞(HEEC)氧化应激和甲基化的影响。方法将细胞分为正常对照组、富锌组、阳性对照组和缺锌组,并分别干预12、24、48 h。比较各组丙二醛(MDA)、超氧化物歧化酶(S... 目的探讨缺锌对经N-甲基-N′-硝基-N-亚硝基胍(MNNG)诱导的人正常食管上皮细胞(HEEC)氧化应激和甲基化的影响。方法将细胞分为正常对照组、富锌组、阳性对照组和缺锌组,并分别干预12、24、48 h。比较各组丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)水平,以及O 6-甲基鸟嘌呤-DNA甲基转移酶(MGMT)、MLH1基因甲基化状态及MGMT蛋白表达水平。结果TPEN对HEEC的半数抑制浓度为1.0μmol/L。4组各时间点MDA、GSH-Px水平比较,差异有统计学意义(P<0.05)。4组12 h时SOD水平比较,差异有统计学意义(P<0.05)。4组MGMT、MLH1基因呈现部分甲基化状态。4组24 h时MGMT蛋白表达水平比较,差异有统计学意义(P<0.05),而在12、48 h时比较,差异无统计学意义(P>0.05)。结论缺锌会致使经MNNG诱导的HEEC出现氧化应激、MGMT和MLH1基因甲基化和MGMT蛋白异常表达。 展开更多
关键词 食管癌 甲基化 氧化应激
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苯胺与氨基甲酸甲酯合成苯氨基甲酸甲酯反应研究 被引量:10
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作者 李其峰 王军威 +2 位作者 董文生 王心葵 彭少逸 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2003年第7期1277-1280,共4页
以无水氯化锌为催化剂 ,考察了温度、时间、催化剂含量及原料配比等条件对合成反应的影响 ,确定了最优化反应条件 ,并初步探讨了反应机理 .最佳反应条件下 MPC收率可达 89.90 % ,选择性为 99.76 % .
关键词 苯胺 氨基甲酸甲酯 合成 苯氨基甲酸甲酯 化学反应 氯化锌 反应温度
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Fe-Ni共掺杂ZnO的制备及其光催化降解甲基橙活性 被引量:43
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作者 傅天华 高倩倩 +2 位作者 刘斐 代华均 寇兴明 《催化学报》 SCIE EI CAS CSCD 北大核心 2010年第7期797-802,共6页
采用溶液法制备了Fe-Ni共掺杂ZnO光催化剂,并运用X射线衍射、扫描电镜和原子发射光谱等对催化剂进行了表征.以甲基橙(MO)为模型污染物,评价了样品的光催化活性,考察了甲基橙初始浓度及其pH值,以及催化剂用量等对光催化反应性能的影响.... 采用溶液法制备了Fe-Ni共掺杂ZnO光催化剂,并运用X射线衍射、扫描电镜和原子发射光谱等对催化剂进行了表征.以甲基橙(MO)为模型污染物,评价了样品的光催化活性,考察了甲基橙初始浓度及其pH值,以及催化剂用量等对光催化反应性能的影响.结果表明,Fe-Ni共掺杂降低了ZnO的结晶度,并促进了晶粒的长大.光催化降解反应表明,Fe-Ni共掺杂显著提高了ZnO光催化降解甲基橙的活性,当催化剂用量为0.6g/L,经120min紫外光照射时,可使甲基橙溶液(10mg/L)降解率达到93.5%. 展开更多
关键词 共掺杂 氧化锌 光催化 甲基橙 降解
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ZnO纳米管的光学性质及其对甲基橙降解的光催化活性 被引量:25
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作者 李长全 罗来涛 熊光伟 《催化学报》 SCIE EI CAS CSCD 北大核心 2009年第10期1058-1062,共5页
以十二烷基硫酸钠为模板剂采用水热法合成了ZnO纳米管,以尿素和ZnSO4为原料制备了ZnO纳米颗粒,并应用透射电镜、X射线衍射、光致发射光谱、拉曼光谱、比表面积测定、傅里叶红外光谱和紫外-可见漫反射光谱等技术对样品进行了表征.结果表... 以十二烷基硫酸钠为模板剂采用水热法合成了ZnO纳米管,以尿素和ZnSO4为原料制备了ZnO纳米颗粒,并应用透射电镜、X射线衍射、光致发射光谱、拉曼光谱、比表面积测定、傅里叶红外光谱和紫外-可见漫反射光谱等技术对样品进行了表征.结果表明,ZnO纳米管的比表面积较大,在λ≈650nm的可见光波段ZnO纳米管开始出现吸收峰,而ZnO纳米颗粒在可见光波段几乎没有吸收.ZnO纳米管和纳米颗粒在紫外光照射下均对甲基橙有降解作用,其中ZnO纳米管的光催化活性较高.随着催化剂用量的增加和光照时间的延长,甲基橙降解率逐渐提高;甲基橙浓度的增大使甲基橙降解率降低. 展开更多
关键词 氧化锌 纳米管 纳米颗粒 甲基橙 降解 光催化活性
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纳米氧化锌的制备及其光催化活性研究 被引量:19
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作者 洪若瑜 徐丽萍 +2 位作者 任志强 李忻 李洪钟 《化工环保》 CAS CSCD 北大核心 2005年第3期231-234,共4页
以硫酸锌和尿素为原料,采用均相沉淀法制备纳米ZnO颗粒,并用TEM,IR,TGA,XRD等测试手段对其进行了表征。以紫外灯为光源,以纳米ZnO为光催化剂,氧化水溶液中的甲基橙。研究了催化剂的用量、光照时间、空气流量、光源性质对甲基橙降解的影... 以硫酸锌和尿素为原料,采用均相沉淀法制备纳米ZnO颗粒,并用TEM,IR,TGA,XRD等测试手段对其进行了表征。以紫外灯为光源,以纳米ZnO为光催化剂,氧化水溶液中的甲基橙。研究了催化剂的用量、光照时间、空气流量、光源性质对甲基橙降解的影响及ZnO粉体掺杂Ag+对其活性的影响。实验结果表明,掺杂Ag+后的纳米ZnO光催化效能大大提高。 展开更多
关键词 纳米粉体 氧化锌 均相沉淀 光催化氧化 甲基橙废水
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仲丁醇脱氢制甲乙酮的Cu-ZnO催化剂 被引量:18
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作者 姜广申 胡云峰 +3 位作者 蔡俊 许鹏 丛亮 方菲 《化工进展》 EI CAS CSCD 北大核心 2013年第2期352-358,共7页
采用共沉淀法和机械混合法制备了铜锌催化剂,并利用TPR、XRD和N2O吸附分解催化剂表征手段分析了铜锌催化剂中ZnO和Cu在仲丁醇(sec-butanol,SBA)脱氢反应中的作用。研究表明,Cu0是SBA脱氢的活性中心,ZnO具有分散铜物种和抗烧结能力。ZnO... 采用共沉淀法和机械混合法制备了铜锌催化剂,并利用TPR、XRD和N2O吸附分解催化剂表征手段分析了铜锌催化剂中ZnO和Cu在仲丁醇(sec-butanol,SBA)脱氢反应中的作用。研究表明,Cu0是SBA脱氢的活性中心,ZnO具有分散铜物种和抗烧结能力。ZnO能够有效分散铜物种和阻止Cu0烧结的原因是在催化剂制备过程中形成了(CuZn)x(OH)y(CO3)z(x=1,5;y=2,6,z=1,2)前体,经焙烧形成了高分散的CuO-ZnO固溶体。同时,通过SBA催化脱氢反应测试筛选了适宜的Cu/Zn摩尔比,当Cu/Zn为1∶1时,表现出良好的反应活性,常压、240℃下质量空速为17.5 h 1时,该催化剂对SBA转化率达到80.54%,甲乙酮(methyl ethyl ketone,MEK)收率达到76.04%。铜锌催化剂的脱氢活性与Cu0比表面积不呈线性关系,SBA脱氢反应是一结构敏感型反应。 展开更多
关键词 仲丁醇 催化脱氢 甲乙酮 铜锌催化剂
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氧化锌制备及其光催化活性研究 被引量:8
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作者 崔玉民 李慧泉 +3 位作者 苗慧 凡素华 张坤 范峻 《化工新型材料》 CAS CSCD 北大核心 2015年第5期100-102,共3页
以二水合醋酸锌为原料、二甘醇为溶剂,采用非水解溶胶-凝胶过程的方法合成了氧化锌(ZnO)光催化剂,并用XRD对其进行了表征。以甲基橙为光催化反应的模型化合物,考察了ZnO光催化剂的紫外及可见光催化活性。探索添加不同清除剂(异丙醇、草... 以二水合醋酸锌为原料、二甘醇为溶剂,采用非水解溶胶-凝胶过程的方法合成了氧化锌(ZnO)光催化剂,并用XRD对其进行了表征。以甲基橙为光催化反应的模型化合物,考察了ZnO光催化剂的紫外及可见光催化活性。探索添加不同清除剂(异丙醇、草酸铵、对苯醌、H2O2酶)后对紫外及可见光催化活性的影响;以对苯二甲酸作为探针分子,结合化学荧光技术研究了ZnO光催化剂表面羟基自由基的生成。实验结果表明:此方法制备的ZnO具有良好的光催化性能。 展开更多
关键词 氧化锌 光催化 甲基橙 荧光技术
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制备高碳醇用Cu-Zn-Zr催化剂的研究 被引量:16
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作者 刘寿长 苏运来 陈诵英 《催化学报》 SCIE EI CAS CSCD 北大核心 1999年第4期445-449,共5页
研究了制备高碳醇用新的催化体系CuZnZr.CuZnZr催化剂可用Cu(NO3)2,Zn(NO3)2,ZrOCl2和Na2CO3为原料,采用并流共沉淀法制备.研究结果表明,CuZnZr催化剂对脂肪酸甲酯加氢制备高碳脂... 研究了制备高碳醇用新的催化体系CuZnZr.CuZnZr催化剂可用Cu(NO3)2,Zn(NO3)2,ZrOCl2和Na2CO3为原料,采用并流共沉淀法制备.研究结果表明,CuZnZr催化剂对脂肪酸甲酯加氢制备高碳脂肪醇具有很高的活性.催化剂的活性测定结果及XRD和TPR表征结果表明,Cu和Zn都是该催化剂的活性组分,Cu0和ZnO是其活性物相,Zr组分以ZrO物相存在,对活性组分起着间隔分散作用.用ASAP2000型物理吸附仪测定了催化剂的比表面积、比孔容、孔结构和孔径分布。 展开更多
关键词 脂肪酸甲酯 加氢 高碳醇 催化剂
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