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Regeneration of Acid Orange 7 Exhausted Granular Activated Carbon Using Pulsed Discharge Plasmas 被引量:1
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作者 王慧娟 郭贺 +1 位作者 刘永杰 依成武 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第10期881-886,共6页
In this paper, a pulsed discharge plasma (PDP) system with a multi-needle-to-plate electrodes geometry was set up to investigate the regeneration of acid orange 7 (AO7) exhausted granular activated carbon (GAC).... In this paper, a pulsed discharge plasma (PDP) system with a multi-needle-to-plate electrodes geometry was set up to investigate the regeneration of acid orange 7 (AO7) exhausted granular activated carbon (GAC). Regeneration of GAC was studied under different conditions of peak pulse discharge voltage and water pH, as well as the modification effect of GAC by the pulse discharge process, to figure out the regeneration efficiency and the change of the GAC structure by the PDP treatment. The obtained results showed that there was an appropriate peak pulse voltage and an optimal initial pH value of the solution for GAC regeneration. Analyses of scanning electron microscope (SEM), Boehm titration, Brunauer-Emmett-Teller (BET), Horvath-Kawazoe (HK), and X-ray Diffraction (XRD) showed that there were more mesopore and macropore in the regenerated GAC and the structure turned smoother with the increase of discharge voltage; the amount of acidic functional groups on the GAC surface increased while the amount of basic functional groups decreased after the regeneration process. From the result of the XRD analysis, there were no new substances produced on the GAC after PDP treatment. 展开更多
关键词 pulsed discharge plasma acid orange 7 granular activated carbon REGENERATiON pore structure functional groups
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Adsorption of acid orange 7 from aqueous solutions by bottom ash
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作者 QU Yan-zhi SUN Wei-ling YE Zheng-fang YU Qing NI Jin-ren 《Journal of Environmental Science and Engineering》 2008年第10期1-13,共13页
Bottom ash. a power plant waste, was used to adsorb acid orange 7. The adsorption of acid orange 7 in aqueous solutions onto bottom ash was studied as functions of particle size. dosage, initial concentration and agit... Bottom ash. a power plant waste, was used to adsorb acid orange 7. The adsorption of acid orange 7 in aqueous solutions onto bottom ash was studied as functions of particle size. dosage, initial concentration and agitation time by batch experiments. Under conditions of bottom ash dosage of 1.5 g/50 ml and 5 g/50 ml for 〈0.074 mm and 0.074 mm-0.2 mm of bottom ash, respectively, it could achieve 99.1% and 87.6% dye removal efficiency. The adsorption isotherms for the bottom ash could be well described by both Freundlich and Langmuir isotherms. The calculated dye adsorption capacities of bottom ash for the particle size of 0.074 mm -0.2 mm and 〈0.074 mm were 2.78 mg/g and 10.21 mg/g, respectively. The results indicated that the dye uptake process fitted to the pseudo-first-order kinetic model better than the pseudo-second-order. The data were also fitted to intraparticle diffusion model by two adsorption stages, due to the difference in rate of mass transfer in the initial and final stages of adsorption. Significant variations were observed in the FTIR spectra and Stem photographs of bottom ash after adsorption. The column parameters were calculated by breakthrough curves at different flow rates and bed depths. 展开更多
关键词 ADSORPTiON bottom ash acid orange 7 asotherm kinctics column operation
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EFFECT OF CIS-9, TRANS-11-CONJUGATED LINOLEIC ACID ON CELL CYCLE OF MAMMARY ADENOCARCINOMA CELLS(MCF-7) 被引量:1
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作者 刘家仁 陈炳卿 +3 位作者 韩晓辉 杨艳梅 郑玉梅 刘瑞海 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2002年第2期93-99,共7页
Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell ... Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1). 展开更多
关键词 Mammary adenocarcinoma cells (McF-7) cis-9 trans-11-conjugated linoleic acid(c9 t11-cLA) iMMUNOcYTOcHEMiSTRY cell cycle inhibition
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18β- glycyrrhetinic acid inhibits apoptosis of renal tubular epithelial cells via enhancing level of BMP-7 epigenetically through targeting HDAC2
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《中国药理学通报》 CAS CSCD 北大核心 2015年第B11期101-102,共2页
Cisplatin (CP) , a highly effective and widely used chemotherapeutic agent, has a major limitation for its nephrotoxicity. We recently identified a novel strategy for attenuating its nephrotoxicity in chemotherapy b... Cisplatin (CP) , a highly effective and widely used chemotherapeutic agent, has a major limitation for its nephrotoxicity. We recently identified a novel strategy for attenuating its nephrotoxicity in chemotherapy by an ef- fective adjuvant via epigenetic modification through targeting Histone deacetylase 2 (HDAC2). Glycyrrhizic acid (GA) ,a major active component of Licorice, was described here for its new application. Molecular docking and Surface Plasmon resonance (SPR) assay firstly reported that 18βGA, GA metabolite in vivo, could directly bind to HDAC2 and prevent HDAC2 activation. The effects and mechanisms of GA and its major metabolite 18βGA were assessed in CP-induced acute kidney injury (AKI) in C57BL/6 mice, and in CP-treated HK-2 and mTEC cells lines. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and flow cytometry (FCM) results confirmed that GA and 18βGA could inhibit apoptosis of renal tubular epithelial cells induced by CP in vivo and in vitro. Western blot and immunofluorescence results demonstrated that the expression of bone morphogenetic protein- 7 (BMP-7) , a protective molecule in renal inflammation, was clearly induced by 18βGA in AKI models while siR- NA BMP-7 could reduce the inhibitory effect of 18βGA on apoptosis. Results of current study indicated that 18βGA inhibited apoptosis of renal tubular epithelial cells via enhancing level of BMP-7 epigenetically through targeting HDAC2, therefore protecting against CP-induced AKI. These available evidence, which led to an improved under- standing of molecular recognition, suggested that 18βGA could serve as a potential clinical adjuvant in chemothera- 展开更多
关键词 acute KiDNEY injury ( AKi ) glycyrrhizic acid ( cA ) 18β-glycyrrhetinic acid ( 18βc A ) histonedeacetylase2 (HDAc2) bonemorphogenetic protein-7 ( BMP-7 )
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Electrical stress and acid orange 7 synergistically clear the blockage of electron flow in the methanogenesis of low-strength wastewater
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作者 Ze-Chong Guo Min-Hua Cui +6 位作者 Chun-Xue Yang Hong-Liang Dai Tong-Yi Yang Lin-Zhi Zhai Yong Chen Wen-Zong Liu Ai-Jie Wang 《Environmental Science and Ecotechnology》 SCIE 2024年第4期291-299,共9页
Energy recovery from low-strength wastewater through anaerobic methanogenesis is constrained by limited substrate availability.The development of efficient methanogenic communities is critical but challenging.Here we ... Energy recovery from low-strength wastewater through anaerobic methanogenesis is constrained by limited substrate availability.The development of efficient methanogenic communities is critical but challenging.Here we develop a strategy to acclimate methanogenic communities using conductive carrier(CC),electrical stress(ES),and Acid Orange 7(AO7)in a modified biofilter.The synergistic integration of CC,ES,and AO7 precipitated a remarkable 72-fold surge in methane production rate compared to the baseline.This increase was attributed to an altered methanogenic community function,independent of the continuous presence of AO7 and ES.AO7 acted as an external electron acceptor,accelerating acetogenesis from fermentation intermediates,restructuring the bacterial community,and enriching electroactive bacteria(EAB).Meanwhile,CC and ES orchestrated the assembly of the archaeal community and promoted electrotrophic methanogens,enhancing acetotrophic methanogenesis electron flow via a mechanism distinct from direct electrochemical interactions.The collective application of CC,ES,and AO7 effectively mitigated electron flow impediments in low-strength wastewater methanogenesis,achieving an additional 34%electron recovery from the substrate.This study proposes a new method of amending anaerobic digestion systems with conductive materials to advance wastewater treatment,sustainability,and energy self-sufficiency. 展开更多
关键词 METHANOGENESiS conductive carrier Electrical stress acid orange 7 Electron transfer
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Ni/GAC催化过硫酸钠降解酸性橙7 被引量:2
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作者 张永丽 唐嘉 张静 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2017年第2期137-143,共7页
为提高活性炭活化过硫酸盐处理有机废水的效率,采用浸渍-高温煅烧法制备负载型镍/颗粒活性炭(Ni/GAC)催化剂,采用SEM、FT-IR和XPS对催化剂进行分析,考察了硫酸盐投加量c(PDS)、Ni/GAC投加量m(Ni/GAC)和p H值对Ni/GAC活化过硫酸钠(PDS)... 为提高活性炭活化过硫酸盐处理有机废水的效率,采用浸渍-高温煅烧法制备负载型镍/颗粒活性炭(Ni/GAC)催化剂,采用SEM、FT-IR和XPS对催化剂进行分析,考察了硫酸盐投加量c(PDS)、Ni/GAC投加量m(Ni/GAC)和p H值对Ni/GAC活化过硫酸钠(PDS)降解酸性橙7(AO7)的影响,并验证了反应体系内存在的主要氧化物种.结果显示:活性炭表面负载物为Ni O,同时新增大量羧基、内酯基和酚羟基,Ni/GAC具有较高的催化活性;AO7去除率随c(PDS)的增加先上升后下降;催化作用随m(Ni/GAC)的增大而提高;不同p H值下的催化降解效率为:中性>碱性>弱酸性>强酸性;在最佳反应条件(即c(PDS)=2 mmol/L、m(Ni/GAC)=2 g、p H=7)下,90 min内AO7去除率达93.9%.该催化体系为羟基自由基(HO·)和硫酸根自由基(SO_4^-·)主导的氧化体系. 展开更多
关键词 催化作用 过硫酸钠 硫酸根自由基 活性炭 酸性橙7
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可剥离TiO_2纳米管光催化共去除酸性橙7和Cr(Ⅵ)的性能研究 被引量:1
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作者 吴晓婧 产启中 +1 位作者 黄浪欢 刘应亮 《功能材料》 EI CAS CSCD 北大核心 2011年第12期2273-2276,2280,共5页
以0.5%(质量分数)NH4F/HF/乙二醇为电解液,采用恒压二次阳极氧化法制备出高度有序的可剥离TiO2纳米管阵列,并对其晶型、形貌以及光催化性能等方面进行了研究。通过XRD测试,可知样品经500和800℃退火,分别得到锐钛矿和金红石型TiO2纳米管... 以0.5%(质量分数)NH4F/HF/乙二醇为电解液,采用恒压二次阳极氧化法制备出高度有序的可剥离TiO2纳米管阵列,并对其晶型、形貌以及光催化性能等方面进行了研究。通过XRD测试,可知样品经500和800℃退火,分别得到锐钛矿和金红石型TiO2纳米管;通过SEM表征,可知所制备的TiO2纳米管管径约为100nm,管长约为25μm。在紫外光照射下,以TiO2纳米管阵列为催化剂,对其光催化降解酸性橙7(AO7)和Cr(Ⅵ)混合水溶液进行了研究。考察了不同晶型、pH值、不同酸性橙7和Cr(Ⅵ)初始浓度对光催化性能的影响。结果表明锐钛矿型样品光催化性能高于金红石型,三元体系TiO2/AO7/Cr(Ⅵ)中,协同效应显著,酸性条件下尤其有利于TiO2纳米管阵列光催化共去除AO7和Cr(Ⅵ)。 展开更多
关键词 TiO2 共去除 酸性橙7
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改性磁性生物质炭对酸性橙7的吸附
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作者 刘传福 张晨 +4 位作者 吴正德 张健 於中烨 陈宏彬 邱祖民 《南昌大学学报(理科版)》 CAS 2024年第1期42-51,共10页
以竹粉水热炭(BC)作为基底,负载Fe 3O 4磁性材料使其具有磁性,同时经共沉淀法在磁性水热炭表面生长层状双氢氧化物(LDH)来提升吸附性能。将制备的材料用于吸附酸性橙7,探究了不同pH、离子浓度、水质、微塑料、腐殖酸等因素的影响,并通过... 以竹粉水热炭(BC)作为基底,负载Fe 3O 4磁性材料使其具有磁性,同时经共沉淀法在磁性水热炭表面生长层状双氢氧化物(LDH)来提升吸附性能。将制备的材料用于吸附酸性橙7,探究了不同pH、离子浓度、水质、微塑料、腐殖酸等因素的影响,并通过SEM、BET、XRD、FT-IR、VSM等表征手段,分析了吸附过程的机理。结果表明:吸附符合Langmuir模型和准二阶动力学模型。在40℃下,平衡吸附量能达到271.64 mg·g^(-1),该吸附剂具有较好的循环吸附效果,循环4次仍具有较好的去除率。 展开更多
关键词 吸附 水热炭 层状双氢氧化物(LDH) 酸性橙7
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Isomerization of linear C5–C7 over Pt loaded on protonated fibrous silica@Y zeolite(Pt/HSi@Y) 被引量:5
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作者 S.Triwahyono A.A.Jalil +2 位作者 S.M.Izan N.S.Jamari N.A.A.Fatah 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第10期163-171,共9页
A novel fibrous silica Y zeolite (HSi@Y) loaded with Pt has been studied based on its ability to produce protonic acid sites originating from molecular hydrogen. The Pt/HSi@Y was prepared using seed assisted crystalli... A novel fibrous silica Y zeolite (HSi@Y) loaded with Pt has been studied based on its ability to produce protonic acid sites originating from molecular hydrogen. The Pt/HSi@Y was prepared using seed assisted crystallization followed by protonation and Pt-loading. The product formed had a spherical morphology with bicontinuous lamellar with a diameter in the range of 500-700 nm. The catalytic activity of the Pt/HSi@Y has been assessed based on light linear alkane (C5-C7) isomerization in a micro-catalytic pulse reactor at 423-623 K. A pyridine IR study confirmed that the introduction of fibrous silica on Y zeolite increased the Lewis acid sites corresponding with the formation of extra-framework Al which led to the generation of more protonic acid sites. A hydrogen adsorbed IR study showed that the protonic acid sites which act as active sites in the isomerization were formed via dissociative-adsorption of molecular hydrogen releasing electrons to the nearby Lewis acid sites. Thus, it is suggested that the presence of Pt and HSi@Y with a high number of Lewis acid as well as weak Bronsted acid sites improved the activity and stability in C5, C6 and C7 isomerization via hydrogen spill-over mechanism. 展开更多
关键词 Pt/HSi@Y FiBROUS silica Y zeolite acidic sites c5-c7 iSOMERiZATiON
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基于二价钴催化氧化脱色酸性橙7的分光光度法快速测定水中过氧乙酸浓度
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作者 许冬梅 陈思颖 +5 位作者 董冬吟 杨仕毅 陈铃心 林晓峰 崔航宇 邹景 《环境化学》 CAS CSCD 北大核心 2024年第9期3165-3173,共9页
文章开发建立了一种快速、简便、准确测定水中过氧乙酸浓度的分光光度方法.该方法基于催化氧化脱色原理,利用Co(Ⅱ)选择性催化过氧乙酸氧化脱色酸性橙7.研究结果表明,酸性橙7脱色程度随过氧乙酸浓度的提高而增加,且酸性橙7在其特征吸收... 文章开发建立了一种快速、简便、准确测定水中过氧乙酸浓度的分光光度方法.该方法基于催化氧化脱色原理,利用Co(Ⅱ)选择性催化过氧乙酸氧化脱色酸性橙7.研究结果表明,酸性橙7脱色程度随过氧乙酸浓度的提高而增加,且酸性橙7在其特征吸收波长484 nm处的吸光度变化值与过氧乙酸浓度具有良好的线性关系.该方法的检测时间仅为1 min、最低检测限为0.48μmol·L^(-1)且线性范围为0—60μmol·L^(-1).共存的过氧化氢以及实际水体水质背景中存在的硫酸根离子、氯离子、碳酸氢根离子、硝酸根离子、腐殖酸和三价铁离子对该方法的测定结果均没有显著影响.该方法还成功运用于监测过氧乙酸活化体系降解双氯芬酸过程中过氧乙酸的浓度变化. 展开更多
关键词 过氧乙酸 测定方法 过氧化氢 酸性橙7 二价钴
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Applications of multi-nuclear magnetic resonance spectroscopy at 7T 被引量:2
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作者 Mary C Stephenson Frances Gunner +6 位作者 Antonio Napolitano Paul L Greenhaff Ian A MacDonald Nadeem Saeed William Vennart Susan T Francis Peter G Morris 《World Journal of Radiology》 CAS 2011年第4期105-113,共9页
AIM: To discuss the advantages of ultra-high field (7T) for 1H and 13C magnetic resonance spectroscopy (MRS) studies of metabolism.METHODS: Measurements of brain metabolites were made at both 3 and 7T using 1H MRS. Me... AIM: To discuss the advantages of ultra-high field (7T) for 1H and 13C magnetic resonance spectroscopy (MRS) studies of metabolism.METHODS: Measurements of brain metabolites were made at both 3 and 7T using 1H MRS. Measurements of glycogen and lipids in muscle were measured using 13C and 1H MRS respectively.RESULTS: In the brain, increased signal-to-noise ratio (SNR) and dispersion allows spectral separation of the amino-acids glutamate, glutamine and γ-aminobutyric acid (GABA), without the need for sophisticated editing sequences. Improved quantification of these metabolites is demonstrated at 7T relative to 3T. SNR was 36% higher, and measurement repeatability (% coefficients of variation) was 4%, 10% and 10% at 7T, vs 8%, 29% and 21% at 3T for glutamate, glutamine and GABA respectively. Measurements at 7T were used to compare metabolite levels in the anterior cingulate cortex (ACC) and insula. Creatine and glutamate levels were found to be significantly higher in the insula compared to the ACC (P < 0.05). In muscle, the increased SNR and spectral resolution at 7T enables interleaved studies of glycogen (13C) and intra-myocellular lipid (IMCL) and extra-myocellular lipid (EMCL) (1H) following exercise and re-feeding. Glycogen levels were significantly decreased following exercise (-28% at 50% VO2 max; -58% at 75% VO2 max). Interestingly, levels of glycogen in the hamstrings followed those in the quadriceps, despite reduce exercise loading. No changes in IMCL and EMCL were found in the study.CONCLUSION: The demonstrated improvements in brain and muscle MRS measurements at 7T will increase the potential for use in investigating human metabolism and changes due to pathologies. 展开更多
关键词 Magnetic resonance spectroscopy 13c 1H 7 Tesla GLUTAMATE GLUTAMiNE γ-aminobutyric acid
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顶头孢霉菌产头孢菌素C发酵培养基优化
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作者 李建平 孟利钢 +2 位作者 张世星 冯涛 于娜娜 《化工管理》 2024年第20期131-135,共5页
以头孢菌素C生产菌株顶头孢霉菌为研究对象,研究了多种氮源对头孢菌素C产量的影响。通过多因子二水平分析实验、爬坡实验和响应面法优化发酵培养基,确定最佳氮源为蛋氨酸、玉米蛋白粉、豆油,最佳发酵培养基配方:蛋氨酸为0.93 g/L、玉米... 以头孢菌素C生产菌株顶头孢霉菌为研究对象,研究了多种氮源对头孢菌素C产量的影响。通过多因子二水平分析实验、爬坡实验和响应面法优化发酵培养基,确定最佳氮源为蛋氨酸、玉米蛋白粉、豆油,最佳发酵培养基配方:蛋氨酸为0.93 g/L、玉米蛋白粉为4.96 g/L、豆油为6.33 g/L。在此发酵配方下,头孢菌素C产量可达33.21 g/L,较初始配方提高16.24%。 展开更多
关键词 头孢菌素c 7-氨基头孢烷酸发酵 顶头孢霉菌 响应面法
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乙酸C_7~C_9酸二甘醇酯的合成 被引量:4
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作者 王文涛 苏娇莲 +2 位作者 吴子良 杨桦 何国信 《精细石油化工》 CAS CSCD 北大核心 2002年第3期1-4,共4页
以SnCl4/SiO2 为催化剂 ,二甘醇与醋酸及C7~C9脂肪酸合成乙酸 C7~C9酸二甘醇酯。讨论了醇酸比、催化剂和带水剂用量以及反应时间、温度等对反应的影响。所得产物作为增塑剂试用于卷烟用醋酸纤维滤咀棒的生产 ,效果与用三醋酸甘油酯... 以SnCl4/SiO2 为催化剂 ,二甘醇与醋酸及C7~C9脂肪酸合成乙酸 C7~C9酸二甘醇酯。讨论了醇酸比、催化剂和带水剂用量以及反应时间、温度等对反应的影响。所得产物作为增塑剂试用于卷烟用醋酸纤维滤咀棒的生产 ,效果与用三醋酸甘油酯作增塑剂基本一致。 展开更多
关键词 乙酸-c7-c9酸二甘醇酯 合成 二甘醇双酯 乙酸 c7-c9脂肪酸 四氯化锡 增塑剂
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C_7~C_9混合脂肪酸甲酯的GC/MS分析 被引量:3
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作者 陈静 丘彦明 +3 位作者 李红兵 杨效和 周宏英 傅宏祥 《石油化工》 CAS CSCD 北大核心 1998年第2期133-135,共3页
对炼油厂蜡裂解烯烃中C6~C8混合烯烃直接进行的羰化产物甲酯进行了分析。通过GC/MS联用技术定性及毛细管气相色谱定量得到各甲酯的结构和含量,给出异构体的数量。初步分析了各C7~C9混合脂肪酸甲酯异构体与相应烯烃的关系。
关键词 GS/MS分析 7 碳9 混合 脂肪酸甲酯 炼油厂
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熊果酸通过影响Bax和Bcl-2的表达诱导MCF-7人乳腺癌细胞凋亡 被引量:13
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作者 张贵平 黎银燕 +1 位作者 吕嘉春 区彗坚 《第四军医大学学报》 北大核心 2005年第20期1877-1880,共4页
目的:探讨中药成分熊果酸(ursolicacid,UA)诱导MCF7人乳腺癌细胞的凋亡作用,并通过分析UA作用后的MCF7细胞Bax,Bcl2,cytochromec蛋白表达的变化,探讨其诱导MCF7细胞凋亡的分子机制.方法:采用细胞培养技术,用0,10,30和50μmol/L的UA处理M... 目的:探讨中药成分熊果酸(ursolicacid,UA)诱导MCF7人乳腺癌细胞的凋亡作用,并通过分析UA作用后的MCF7细胞Bax,Bcl2,cytochromec蛋白表达的变化,探讨其诱导MCF7细胞凋亡的分子机制.方法:采用细胞培养技术,用0,10,30和50μmol/L的UA处理MCF7细胞24h,用Ho染细胞,在荧光显微镜下观察凋亡细胞的形态变化.用0,20和50μmol/L的UA处理MCF7细胞24h,用PI染细胞,在流式细胞仪上测定细胞周期的变化.用0和50μmol/L的UA处理MCF7细胞24h,采用荧光免疫细胞化学SABCCy3法检测Bax,Bcl2,cytochromec蛋白表达,在荧光显微镜下拍照,用QWin图像分析软件测定Bax,Bcl2,cytochromec荧光灰度值.结果:用0,10,30和50μmol/L的UA处理MCF7细胞24h,随着UA浓度增加,在荧光显微镜下出现凋亡细胞增多,细胞呈现典型的凋亡形态学特征,核质浓集和凋亡小体.用0,20和50μmol/L的UA处理MCF7细胞24h,流式细胞仪检测亚G1峰比例分别为0.05,0.22,0.43与对照组5mL/LDMSO比较,50μmol/L的UA使MCF7细胞中的Bax灰度(59.3±7.8,213.6±7.4,P<0.01)和cytochromec灰度(88.2±6.9,188.1±15.4,P<0.01)增加,Bax/Bcl2灰度比值升高(1.0±0.1,2.4±0.4,P<0.01),Bcl2灰度(58.1±6.1,92.1±12.4,P<0.01)稍有增加.UA促进线粒体放释cytochromec进入胞质.结论:UA诱导MCF7细胞凋亡,其机制涉及到Bax/Bcl2比值升高引起线粒体释放cytochromec所依赖的凋亡调节信号通路.表明治疗乳腺癌,UA可能是有效的中药成分. 展开更多
关键词 熊果酸 McF-7细胞 细胞凋亡 基因 Bax 基因.Bcl-2 细胞色素c
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固定化D-氨基酸氧化酶转化头孢菌素C为戊二酰基-7-氨基头孢霉烷酸 被引量:3
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作者 陈少欣 吴文琼 +1 位作者 刘晨 史炳照 《化学反应工程与工艺》 CAS CSCD 北大核心 2003年第3期242-247,共6页
 部分纯化的变异三角酵母D-氨基酸氧化酶(DAO)在碱性条件下变性过氧化氢酶,再与大孔聚甲基丙烯酸缩水甘油酯高聚物共价交联。与游离酶相比,固定化酶的最适反应温度升高,最适pH范围变宽,对温度和pH的稳定性都有明显的提高。固定化DAO在...  部分纯化的变异三角酵母D-氨基酸氧化酶(DAO)在碱性条件下变性过氧化氢酶,再与大孔聚甲基丙烯酸缩水甘油酯高聚物共价交联。与游离酶相比,固定化酶的最适反应温度升高,最适pH范围变宽,对温度和pH的稳定性都有明显的提高。固定化DAO在搅拌反应器中催化头孢霉素C(CPC)转化为戊二酰基-7-氨基头孢霉烷酸(Gl-7-ACA)。以0.03g/mL的CPC为底物,在温度25℃、pH7.2条件下,产物的得率>93%,副产物得率<5%。经过110批反应后,固定化酶保持64%的初始活力。 展开更多
关键词 固定化酶 D-氨基酸氧化酶 转化酶 头孢菌素c 戊二酰基-7-氨基头孢霉烷酸 抗生素 合成
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三角酵母整细胞酶促转化头孢菌素C为戊二酰-7-氨基头孢烷酸 被引量:2
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作者 陈军 朱彤波 +2 位作者 张益棻 杨蕴刘 焦瑞身 《生物工程学报》 CAS CSCD 北大核心 2001年第2期150-154,共5页
研究了利用含D 氨基酸氧化酶 (D aminoacidoxidase ,DAOEC1.4.3 .3)的透性化三角酵母多倍体FA10(TrigonopsisvariabilisFA10 )细胞酶促转化头孢菌素C(cephalosporinC ,CPC)为戊二酰 7 氨基头孢烷酸 (Glutaryl 7 ACA ,GL 7ACA)的反应过... 研究了利用含D 氨基酸氧化酶 (D aminoacidoxidase ,DAOEC1.4.3 .3)的透性化三角酵母多倍体FA10(TrigonopsisvariabilisFA10 )细胞酶促转化头孢菌素C(cephalosporinC ,CPC)为戊二酰 7 氨基头孢烷酸 (Glutaryl 7 ACA ,GL 7ACA)的反应过程和细胞中同时存在的过氧化氢酶 (Catalase ,CAT)通过水解H2 O2 而对转化反应产生的干扰作用及其对策。实验证明适量添加外源H2 O2 (6 % )或在反应体系中加入过氧化氢酶抑制剂NaN3(0 .13mg/mL)可使GL 7ACA生成率分别为 73 0 %和 70 1%。如果将透性化的FA10细胞在 pH10 .5~ 11 0 ,2 0℃条件下保温 30min ,CAT被不可逆性完全钝化 ,以无过氧化氢酶的FA10细胞进行CPC的酶促转化反应 ,GL 7ACA的生成率可达 84%。 展开更多
关键词 三角酵母 D-氨基酸氧化酶 生物转化 戊二酰-7-氨基头孢烷酸 过氧化氢 抗生素
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C_7~C_9脂肪族羧酸的研制 被引量:1
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作者 丘彦明 陈静 +2 位作者 杨效和 童进 付宏祥 《精细石油化工》 CAS CSCD 北大核心 2000年第5期20-22,共3页
首次采用烯烃氢酯基化反应一步生成 C7~ C9脂肪酸甲酯 ,然后皂化水解制得 C7~ C9脂肪族羧酸。主要考察了烯烃羰化的各项制约因素 ,如 :催化剂体系、反应温度、反应压力及时间的影响。同时针对水解条件进行了初步探讨。实验表明在所考... 首次采用烯烃氢酯基化反应一步生成 C7~ C9脂肪酸甲酯 ,然后皂化水解制得 C7~ C9脂肪族羧酸。主要考察了烯烃羰化的各项制约因素 ,如 :催化剂体系、反应温度、反应压力及时间的影响。同时针对水解条件进行了初步探讨。实验表明在所考察范围内的最佳条件下 ,烯烃的转化率达到 82 .1 % ,C7~ C9脂肪酸总收率约78% ,具有一定的工业应用价值。 展开更多
关键词 c6~c8蜡裂烯烃 c7~c8脂肪酸 氢酯基化
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过氧化氢对D-氨基酸氧化酶转化头孢菌素C为戊二酰-7-氨基头孢烯酸反应的影响 被引量:1
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作者 于海军 陈立功 +3 位作者 李阳 闫喜龙 白国义 段学民 《高校化学工程学报》 EI CAS CSCD 北大核心 2006年第1期79-84,共6页
在D-氨基酸氧化酶D1AAO转化头孢菌素C(CPC)为戊二酰基-7-氨基头孢烯酸(Gl-7-ACA)的反应中,所生成的过氧化氢同时与CPC和Gl-7-ACA发生的氧化副反应是造成目标产物收率损失的关键因素之一。通过联用溶氧电极和过氧化氢电极,测定了DAAO转化... 在D-氨基酸氧化酶D1AAO转化头孢菌素C(CPC)为戊二酰基-7-氨基头孢烯酸(Gl-7-ACA)的反应中,所生成的过氧化氢同时与CPC和Gl-7-ACA发生的氧化副反应是造成目标产物收率损失的关键因素之一。通过联用溶氧电极和过氧化氢电极,测定了DAAO转化CPC为Gl-7-ACA的反应体系内溶氧浓度与相应的过氧化氢浓度的变化曲线,测知反应体系中过氧化氢浓度积累最高可达5mmol·L-1。模拟该反应条件下过氧化氢的氧化反应可知,在过氧化氢浓度较低时,溶液的酸性可加速该氧化反应。在中性条件下,过氧化氢浓度为5mmol·L-1时,反应1h后,CPC的氧化损失为2%,Gl-7-ACA的氧化损失为3%。通过改进氧气分布器、搅拌转速和并调控氧气流量以控制溶液中溶解氧的浓度,来适度地降低物系中过氧化氢积累浓度,使反应收率提高了2.2%。 展开更多
关键词 D-氨基酸氧化酶(DAAO) 头孢菌素c(cPc) 过氧化氢 戊二酰基-7-氨基头孢烯酸(G1-7-AcA)
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藤黄酸对乳腺癌细胞MCF-7细胞端粒酶活性及其逆转录酶hTERT mRNA表达的抑制作用研究 被引量:7
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作者 梁小庆 俞军 《实用老年医学》 CAS 2012年第6期483-486,共4页
目的研究藤黄酸对人乳腺癌细胞MCF-7端粒酶活性和端粒酶逆转录酶(hTERT)mRNA表达及其转录调控基因C-myc的影响,以探讨藤黄酸对人乳腺癌细胞端粒酶活性的调控机制。方法藤黄酸作用于人乳腺癌细胞24h、48h、72h后,收集细胞,四甲基偶氮唑盐... 目的研究藤黄酸对人乳腺癌细胞MCF-7端粒酶活性和端粒酶逆转录酶(hTERT)mRNA表达及其转录调控基因C-myc的影响,以探讨藤黄酸对人乳腺癌细胞端粒酶活性的调控机制。方法藤黄酸作用于人乳腺癌细胞24h、48h、72h后,收集细胞,四甲基偶氮唑盐(MTT)比色法检测MCF-7细胞生长抑制率,同时采用PCR-ELISA法检测端粒酶活性、RT-PCR法检测hTERT mRNA的表达、Western blot技术检测C-myc蛋白的表达。结果藤黄酸能明显抑制人乳腺癌细胞MCF-7生长和增埴,对端粒酶活性、hTERT mRNA及转录调控基因C-myc的表达具有抑制作用,并呈明显的时效和量效相关性。结论藤黄酸能够明显抑制人乳腺癌细胞MCF-7增殖,其机制可能是对MCF-7细胞的端粒酶活性及其端粒酶转录调控基因C-myc有较好的抑制作用,提示藤黄酸有可能成为高效低毒的抗肿瘤天然药物。 展开更多
关键词 藤黄酸 人乳腺癌细胞McF-7 端粒酶 端粒酶逆转录酶 c-myc
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