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An Efficient One-step Methyl Esterification of Carboxylic Acid and Deacetylation of Alcohol under BF_3·OEt_2-MeOH 被引量:1
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作者 Shou Fu LU Qin Qin OUYANG +2 位作者 Zhong Wu GUO Biao YU and Yong Zheng HUI(State Key Laboratory of Bioorganic and Natural Products Chemistry,Shanghai Institute of Organic Chemistry, Academia Sinica, Shanghal 200032) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第10期843-844,共2页
An efficient one-step methyl esterification of carboxylic acid and deacetylation of alcohol under BF3O·Et2-MeOH was developed.
关键词 BF An Efficient One-step methyl Esterification of Carboxylic Acid and Deacetylation of alcohol under BF3 OEt2-MeOH
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THE EFFECTS OF MAGNETIC FIELD ON GRAFT COPOLYMERIZATION OF METHYL METHACRYLATE ONTO POLYVINYL ALCOHOL IN THE PRESENCE OF BENZOPHENONE DURING UV IRRADIATION
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作者 黄骏廉 邬青峰 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1990年第2期108-114,共7页
The effects of magnetic field on the graft ratio and stereoregularity of grafts of PVA-g-MMA in the presence ofbenzophenone during UV irradiation are discussed. By means of IR, it was found that the graft ratio was in... The effects of magnetic field on the graft ratio and stereoregularity of grafts of PVA-g-MMA in the presence ofbenzophenone during UV irradiation are discussed. By means of IR, it was found that the graft ratio was increased with the increment of magnetic field strength. Furthermore, application of relative weak magnetic field of 0.4 Tesla had been shown to substantially enhance the stereo-regularity of graft copolymer. The maximum stereo-regularity appeared when the graft ratio approached to 85% with the magnetic field of 1.2 Tesla (T). The resistance to moisture and heat resistance of the grafted copolymer in the presence of magnetic field were also improved. 展开更多
关键词 Magnetic field Graft copolymerization methyl methacrylate Polyvinyl alcohol BENZOPHENONE UV irradiation
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Alcohol promotes renal fibrosis by activating Nox-mediated DNA methylation of Smad7
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作者 Qin YANG Jia-nan WANG +3 位作者 Wei-feng WU Chao LI Jun LI Xiao-ming MENG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期324-324,共1页
OBJECTIVE Alcohol is mainly metabolized through liver and excreted by kidney in the body.Kidney damage has been considered as the secondary to liver injury and kidney dysfunction is common in hospitalized patients wit... OBJECTIVE Alcohol is mainly metabolized through liver and excreted by kidney in the body.Kidney damage has been considered as the secondary to liver injury and kidney dysfunction is common in hospitalized patients with severe alcoholic hepatitis.Both acute and chronic alcoholism accumulation can compromise kidney function,although alcoholic kidney disease has drawn much more attention recently,the methodology for establishing the in vivo and in vitro alcoholic renal fibrosis models are still lacking,and the underlying mechanisms are to be determined.METHODS and RESULTS Mice were feed with a liquid diet containing alcohol for 4 weeks,8 weeks and 12 weeks respectively,results of Masson′ s Trichrome staining showed that kidney fibrosis peaked in 8-week model group,which consistent with the results of albumin assay,Western blot,immunostaining and real-time PCR of collagen I and α-SMA.In vitro study also confirmed that ethanol upregulated the level of fibrotic index.es,including collagen I and α-SMA,in tubular epithelial cells(HK2 cells).Additionally,both in vivo and in vitro studies showed that Smad7 was decreased and Smad3 was highly activated.Then we further detected the underlying mechanisms by which alcohol induced the imbalance of Smad7 and Smad3.Results of Genome-wide methylation sequencing found DNA methylation of Smad7 in the alcoholic fibrosis kidney,which may be mainly mediated by DNA methyltransferase 1(DNMT1),because knock.down of DNMT1,but not DNMT2 and 3,largely restored Smad7 level in ethanol-treated HK2 cells.Con.sequently,we found that NADPH Oxidases(nox)-mediated oxidative stress is the major force upregu.lating DNMT1,since knockdown of Nox2 and 4 could both decrease DNMT1 while rebalancing Smad7/Smad3 axis,and thereby relieved ethanol-induced fibrotic response in HK2 cells.More importantly,intraperitoneal injection of apocynin,an inhibitor of NADPH oxidoreductase,attenuated renal fibrosis in alcoholic kidney fibrosis mouse model.CONCLUSION By establishing the novel in vivo and in vitro models,we found that through activating oxidative stress-induced DNA methylation of Smad7,alcohol induces renal fibrosis by breaking the balance between Smad7 and Smad3.Elimination of Nox-mediated oxidative stress may be a potential therapy for treatment of long-term alcohol abuse-induced kidney fibrosis. 展开更多
关键词 肝脏代谢 酒精肝 治疗方法 临床分析
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CAFs促进ADH1B甲基化对卵巢癌细胞增殖及侵袭的影响
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作者 李泽莲 季维雪 +2 位作者 杨媛媛 肖兰 曹云霞 《安徽医科大学学报》 CAS 北大核心 2024年第8期1377-1384,共8页
目的 探讨肿瘤相关成纤维细胞(CAFs)分泌的IL-6对卵巢癌细胞增殖及侵袭的影响及机制。方法 收取新鲜离体上皮性卵巢癌及正常卵巢上皮组织,分离纯化获得CAFs及正常卵巢成纤维细胞(NFs);蛋白质印迹和免疫荧光实验检测上皮细胞和成纤维细... 目的 探讨肿瘤相关成纤维细胞(CAFs)分泌的IL-6对卵巢癌细胞增殖及侵袭的影响及机制。方法 收取新鲜离体上皮性卵巢癌及正常卵巢上皮组织,分离纯化获得CAFs及正常卵巢成纤维细胞(NFs);蛋白质印迹和免疫荧光实验检测上皮细胞和成纤维细胞标志物α-平滑肌动蛋白(α-SMA)、上皮型钙黏附素(E-cadherin)表达;收集CAFs和NFs培养上清液与卵巢癌SKOV3细胞建立间接共培养体系,细胞分为SKOV3单独培养(SKOV3)组、SKOV3与NFs上清液(NFs)组及SKOV3与CAFs上清液(CAFs)组;细胞免疫组化检测SKOV3细胞共CAFs及NFs上清液培养后乙醇脱氢酶1B(ADH1B)表达;甲基化特异性PCR (MSP)、逆转录实时荧光定量PCR(RT-qPCR)、酶联免疫吸附试验(ELISA)及蛋白质印迹实验分别检测甲基化抑制剂5-氮杂-2′-脱氧胞苷(5-Aza-dC)干预前后各组细胞ADH1B mRNA表达及甲基化状态、信号转导和激活因子3(STAT3)蛋白磷酸化水平;细胞计数试剂盒8(CCK-8)法及Transwell实验分别检测IL-6抑制剂LMT-286及重组IL-6 (rhIL-6)对细胞增殖及侵袭能力的影响。结果 肿瘤成纤维细胞中高表达α-SMA,极低表达E-cadherin;相比较SKOV3组及NFs组,CAFs组ADH1B mRNA及蛋白表达明显下调,同时CAFs组细胞上清液中IL-6水平较SKOV3组及NFs组明显升高;5-Aza-dC作用后,ADH1B甲基化部分逆转;三组细胞ADH1B mRNA和蛋白表达均增加,CAFs组STAT3磷酸化水平下降;LMT-286及rhIL-6干预均仅抑制或促进CAFs组细胞增殖和侵袭,而SKOV3组和NFs组无明显改变。结论 CAFs通过IL-6/STAT3信号通路增强ADH1B甲基化促进卵巢癌细胞增殖和侵袭。 展开更多
关键词 乙醇脱氢酶1B 甲基化 5-氮杂-2′-脱氧胞苷 白细胞介素-6 卵巢癌 细胞增殖
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Cu-Zn-Zr催化剂用于苯甲酸甲酯加氢制苯甲醇的研究
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作者 张容众 张鹏程 +1 位作者 巩笑笑 董明会 《石油炼制与化工》 CAS CSCD 北大核心 2024年第12期31-37,共7页
采用共沉淀法制备了一系列Cu-Zn-Zr催化剂,考察了其对苯甲酸甲酯选择性加氢制苯甲醇的催化性能。当催化剂中Cu/Zn/Zr物质的量之比控制在5/6/4,并经过650℃高温焙烧后,其催化性能表现突出。为了进一步优化苯甲酸甲酯加氢制备苯甲醇的反... 采用共沉淀法制备了一系列Cu-Zn-Zr催化剂,考察了其对苯甲酸甲酯选择性加氢制苯甲醇的催化性能。当催化剂中Cu/Zn/Zr物质的量之比控制在5/6/4,并经过650℃高温焙烧后,其催化性能表现突出。为了进一步优化苯甲酸甲酯加氢制备苯甲醇的反应条件,在高压搅拌釜中考察了反应温度、反应压力及反应时间对反应性能的影响。结果表明,在反应温度160℃、压力7 MPa、反应时间10 h的条件下,苯甲酸甲酯的转化率为88.1%,苯甲醇的选择性可达95.21%。通过N_(2)吸附-脱附、X射线衍射、H_(2)程序升温还原、NH_(3)程序升温脱附、X射线光电子能谱、透射电子显微镜等手段对催化剂进行了表征,发现Zr元素的引入显著提升了苯甲醇的选择性;金属Cu纳米粒子的高度分散有利于提高催化剂的活性和稳定性;催化剂表面呈弱酸性有利于催化剂活性的提高。这些因素的协同作用使得催化剂在苯甲酸甲酯制苯乙醇反应中表现出优异的性能。 展开更多
关键词 Cu-Zn-Zr催化剂 选择性加氢 苯甲酸甲酯 苯甲醇
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有色冶炼污酸治理中硫化氢气体制取工艺的选择研究
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作者 陈珑文 陈钢 +2 位作者 蔡兵 杨洪才 蔡辉 《云南冶金》 2024年第3期84-88,共5页
以某公司污酸治理升级改造项目所需的硫化氢气体制取工艺选择为实例,对Na_(2)S/NaHS酸解法、氢气与硫磺合成法制取硫化氢工艺,以及甲醇裂解、天然气蒸气转化制氢方案进行综合对比分析。综合多种影响因素研究选取了甲醇-硫磺合成硫化氢... 以某公司污酸治理升级改造项目所需的硫化氢气体制取工艺选择为实例,对Na_(2)S/NaHS酸解法、氢气与硫磺合成法制取硫化氢工艺,以及甲醇裂解、天然气蒸气转化制氢方案进行综合对比分析。综合多种影响因素研究选取了甲醇-硫磺合成硫化氢工艺治理污酸废水。 展开更多
关键词 硫化氢 酸解法 合成法 甲醇裂解 甲醇-硫磺合成 污酸治理
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丹葛解酲汤对酒精性肝病大鼠DNA甲基化转移酶表达的影响
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作者 王铭 马丽 徐建虎 《河北中医》 2024年第11期1838-1842,共5页
目的观察丹葛解酲汤对酒精性肝病(ALD)大鼠DNA甲基化转移酶(DNMTs)表达的影响。方法将96只SD大鼠随机分为空白组13只、造模组83只,造模组采用白酒灌胃法建立ALD模型,将成功造模的68只大鼠随机分为模型组、丹葛解酲汤高剂量组、丹葛解酲... 目的观察丹葛解酲汤对酒精性肝病(ALD)大鼠DNA甲基化转移酶(DNMTs)表达的影响。方法将96只SD大鼠随机分为空白组13只、造模组83只,造模组采用白酒灌胃法建立ALD模型,将成功造模的68只大鼠随机分为模型组、丹葛解酲汤高剂量组、丹葛解酲汤低剂量组、益肝灵片组,每组17只,分别进行干预。干预结束后采用赖氏法检测血清中丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)的含量,酶联免疫吸附法检测血清DNMT1、DNMT3a、DNMT3b的含量,实时荧光定量聚合酶链式反应(RT-PCR)检测肝脏组织中DNMT1、DNMT3a、DNMT3b mRNA表达水平。结果与空白组比较,模型组AST、ALT含量明显升高(P<0.01),DNMT1、DNMT3a含量明显降低(P<0.01),DNMT1mRNA、DNMT3a mRNA、DNMT3b mRNA表达水平明显降低(P<0.01)。与模型组比较,益肝灵片组AST、ALT、DNMT1、DNMT3a、DNMT1mRNA、DNMT3a mRNA、DNMT3b mRNA明显升高(P<0.01);丹葛解酲汤高剂量组AST、ALT、DNMT1、DNMT3a、DNMT1mRNA、DNMT3a mRNA、DNMT3b mRNA明显升高(P<0.01);丹葛解酲汤低剂量组ALT、DNMT1、DNMT3a mRNA明显升高(P<0.05,P<0.01)。结论丹葛解酲汤通过上调ALD大鼠DNMTs的表达,进而影响甲基化状态,可能是其防治ALD的作用机制之一。 展开更多
关键词 酒精性肝病 大鼠模型 DNA甲基化 甲基化转移酶 药理实验 中药
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碱催化p-QMs的1,6-共轭加成合成二芳基甲基(硫)醚
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作者 罗金华 陈阳 +2 位作者 王欣 李蕾 王贺 《辽宁石油化工大学学报》 CAS 2024年第4期1-9,共9页
在摩尔分数为20%的氢氧化钠的催化作用下,实现了对亚甲基苯醌(p-QMs)与醇(或硫酚)的溶剂解反应,即p-QMs的1,6-共轭加成反应,以37%~95%的产率制备了一系列二芳基甲基(硫)醚类化合物。结果表明,该反应具有操作简便、反应条件温和高效、官... 在摩尔分数为20%的氢氧化钠的催化作用下,实现了对亚甲基苯醌(p-QMs)与醇(或硫酚)的溶剂解反应,即p-QMs的1,6-共轭加成反应,以37%~95%的产率制备了一系列二芳基甲基(硫)醚类化合物。结果表明,该反应具有操作简便、反应条件温和高效、官能团耐受性良好等特点;该方法易于放大,能以80%的产率得到二芳基甲基乙基醚,为后期的潜在应用与转化提供了可能。 展开更多
关键词 碱催化 对亚甲基苯醌 1 6-共轭加成 二芳基甲基醚
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甲基嘧啶磷的绿色合成研究
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作者 竺来发 尤瑶瑶 +4 位作者 张海涛 干兴利 张秋影 刘双瑾 李艳琼 《精细化工中间体》 CAS 2024年第1期14-16,共3页
以嘧啶醇和碳酸钾水溶液在有机溶剂中反应减压脱水,生成嘧啶醇钾盐与甲基氯化物进行缩合反应,经过滤、减压浓缩得到甲基嘧啶磷。优化的反应条件为:以甲苯为溶剂,n(嘧啶醇)∶n(碳酸钾)=1.0∶2.0,嘧啶醇钾盐含水量<0.1%,反应温度30~40... 以嘧啶醇和碳酸钾水溶液在有机溶剂中反应减压脱水,生成嘧啶醇钾盐与甲基氯化物进行缩合反应,经过滤、减压浓缩得到甲基嘧啶磷。优化的反应条件为:以甲苯为溶剂,n(嘧啶醇)∶n(碳酸钾)=1.0∶2.0,嘧啶醇钾盐含水量<0.1%,反应温度30~40℃,反应时间6 h。优化条件下,甲基嘧啶磷纯度98.5%,收率92.6%,该工艺转化率高、收率高、三废少,符合绿色环保生产理念,具有工业化应用前景。 展开更多
关键词 嘧啶醇 甲基嘧啶磷 碳酸钾 绿色合成
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顺-3-己烯酸甲酯还原制备叶醇的工艺研究
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作者 吴兵 王选智 《当代化工研究》 CAS 2024年第3期150-153,共4页
以顺-3-己烯酸甲酯为原料,探究不同反应体系对叶醇合成收率的影响。并优化了以顺-3-己烯酸甲酯、乙醇、氯化钙为原料的还原体系工艺条件,得到的最优反应条件为:顺-3-己烯酸甲酯用量为38.4g,m(95%乙醇):m(顺-3-己烯酸甲酯)=6;n(CaCl_(2))... 以顺-3-己烯酸甲酯为原料,探究不同反应体系对叶醇合成收率的影响。并优化了以顺-3-己烯酸甲酯、乙醇、氯化钙为原料的还原体系工艺条件,得到的最优反应条件为:顺-3-己烯酸甲酯用量为38.4g,m(95%乙醇):m(顺-3-己烯酸甲酯)=6;n(CaCl_(2)):n(顺-3-己烯酸甲酯)=0.8;n(NaBH_(4)):n(顺-3-己烯酸甲酯)=1.2,反应温度20℃,反应1h,叶醇收率为80.92%,并在此基础上扩大到公斤级反应,最终得到叶醇收率为80%以上,具有广阔的工业化应用前景。 展开更多
关键词 顺-3-己烯酸甲酯 叶醇 还原 硼氢化钠
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Adipose tissue-liver axis in alcoholic liver disease 被引量:6
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作者 Zhi-Gang Wang Xiao-Bing Dou +1 位作者 Zhan-Xiang Zhou Zhen-Yuan Song 《World Journal of Gastrointestinal Pathophysiology》 CAS 2016年第1期17-26,共10页
Alcoholic liver disease(ALD) remains an important health problem worldwide. The disease spectrum is featured by early steatosis, steatohepatitis(steatosis with inflammatory cells infiltration and necrosis), with some ... Alcoholic liver disease(ALD) remains an important health problem worldwide. The disease spectrum is featured by early steatosis, steatohepatitis(steatosis with inflammatory cells infiltration and necrosis), with some individuals ultimately progressing to fibrosis/cirrhosis. Although the disease progression is well characterized, no effective therapies are currently available for the treatment in humans. The mechanisms underlying the initiation and progression of ALD are multifactorial and complex. Emerging evidence supports that adipose tissue dysfunction contributes to the pathogenesis of ALD. In the first part of this review, we discuss the mechanisms whereby chronic alcohol exposure contributed to adipose tissue dysfunction, including cell death, inflammation and insulin resistance. It has been long known that aberrant hepatic methionine metabolism is a major metabolic abnormality induced by chronic alcohol exposure and plays an etiological role in the pathogenesis of ALD. The recent studies in our group documented the similar metabolic effect of chronic alcohol drinking on methionine in adipose tissue. In the second part of this review, we also briefly discuss the recent research progress in the field with a focus on how abnormal methionine metabolism in adipose tissue contributes to adipose tissue dysfunction and liver damage. 展开更多
关键词 alcohol LIPOLYSIS ADIPOSE methylATION METHIONINE LIVER
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Alcohol,nutrition and liver cancer:Role of Toll-like receptor signaling 被引量:12
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作者 Samuel W French Joan Oliva +1 位作者 Barbara A French Fawzia Bardag-Gorce 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第11期1344-1348,共5页
This article reviews the evidence that ties the development of hepatocellular carcinoma (HCC) to the natural immune pro-inflammatory response to chronic liver disease, with a focus on the role of Toll-like receptor (T... This article reviews the evidence that ties the development of hepatocellular carcinoma (HCC) to the natural immune pro-inflammatory response to chronic liver disease, with a focus on the role of Toll-like receptor (TLR) signaling as the mechanism of liver stem cell/progenitor transformation to HCC. Two exemplary models of this phenomenon are reviewed in detail. One model applies chronic ethanol/lipopolysaccharide feeding to the activated TLR4 signaling pathway. The other applies chronic feeding of a carcinogenic drug, in which TLR2 and 4 signaling pathways are activated. In the drug-induced model, two major methyl donors, S-adenosylmethionine and betaine, prevent the upregulation of the TLR signaling pathways and abrogate the stem cell/progenitor proliferation response when fed with the carcinogenic drug. This observation supports a nutritional approach to liver cancer prevention and treatment. The observation that upregulation of the TLR signaling pathways leads to liver tumor formation gives evidence to the popular concept that the chronic pro-inflammatory response is an important mechanism of liver oncogenesis. It provides a nutritional approach, which could prevent HCC from developing in many chronic liver diseases. 展开更多
关键词 Toll-like receptor Hepatocellular carcinoma methyl donors Epigenetic processes Inflammation alcohol Drug toxicity LIPOPOLYSACCHARIDES
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Aberrant post-translational protein modifications in the pathogenesis of alcohol-induced liver injury 被引量:3
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作者 Natalia A Osna Wayne G Carter +6 位作者 Murali Ganesan Irina A Kirpich Craig J Mc Clain Dennis R Petersen Colin T Shearn Maria L Tomasi Kusum K Kharbanda 《World Journal of Gastroenterology》 SCIE CAS 2016年第27期6192-6200,共9页
It is likely that the majority of proteins will undergo post-translational modification, be it enzymatic or non-enzymatic. These modified protein(s) regulate activity, localization and interaction with other cellular ... It is likely that the majority of proteins will undergo post-translational modification, be it enzymatic or non-enzymatic. These modified protein(s) regulate activity, localization and interaction with other cellular molecules thereby maintaining cellular hemostasis. Alcohol exposure significantly alters several of these post-translational modifications leading to impairments of many essential physiological processes. Here, we present new insights into novel modifications following ethanol exposure and their role in the initiation and progression of liver injury. This critical review condenses the proceedings of a symposium at the European Society for the Biomedical Research on Alcoholism Meeting held September 12-15, 2015, in Valencia, Spain. 展开更多
关键词 alcohol Acetylation Liver Carbonylation methylation Dysfunction methylATION Glycosylation Phosphorylation Ubiquitination SUMOYLATION BETAINE Post-translational protein modification
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改性聚乙烯醇协同硅酸盐水泥制高强防水石膏
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作者 徐海祥 夏举佩 《应用化学》 CAS CSCD 北大核心 2024年第8期1131-1145,共15页
以脱硫石膏为基料,以液碱活化聚甲基氢硅氧烷(PMHS)催化改性聚乙烯醇(PVA)防水剂协同硅酸盐水泥研发高强防水石膏。探究了改性PVA防水剂、硅酸盐水泥对脱硫石膏标准试块表面吸水率、力学性能和软化系数的影响;通过红外光谱确定改性疏水... 以脱硫石膏为基料,以液碱活化聚甲基氢硅氧烷(PMHS)催化改性聚乙烯醇(PVA)防水剂协同硅酸盐水泥研发高强防水石膏。探究了改性PVA防水剂、硅酸盐水泥对脱硫石膏标准试块表面吸水率、力学性能和软化系数的影响;通过红外光谱确定改性疏水剂、硅酸盐水泥单独及协同研发强防水石膏的连接形式;通过热重仪分析不同掺加剂对石膏热稳定性的影响;研究表明,改性PVA防水剂协同硅酸盐水泥制高强防水石膏的最佳配比为:防水剂120 g、硅酸盐水泥150 g,此时表面吸水率9.35%,绝干抗压强度22.54 MPa、软化系数67.57%,同时有效提高了纸面石膏板的热稳定性。 展开更多
关键词 液碱活化甲基含氢硅油 催化改性 改性PVA疏水剂 热稳定性 高强防水石膏
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Prolonged feeding with guanidinoacetate, a methyl group consumer, exacerbates ethanol-induced liver injury 被引量:2
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作者 Natalia A Osna Dan Feng +5 位作者 Murali Ganesan Priya F Maillacheruvu David J Orlicky Samuel W French Dean J Tuma Kusum K Kharbanda 《World Journal of Gastroenterology》 SCIE CAS 2016年第38期8497-8508,共12页
AIM To investigate the hypothesis that exposure to guanidinoacetate(GAA, a potent methyl-group consumer) either alone or combined with ethanol intake for a prolonged period of time would cause more advanced liver path... AIM To investigate the hypothesis that exposure to guanidinoacetate(GAA, a potent methyl-group consumer) either alone or combined with ethanol intake for a prolonged period of time would cause more advanced liver pathology thus identifying methylation defects as the initiator and stimulator for progressive liver damage.METHODS Adult male Wistar rats were fed the control or ethanolLieber De Carli diet in the absence or presence of GAA supplementation. At the end of 6 wk of the feeding regimen, various biochemical and histological analyses were conducted. RESULTS Contrary to our expectations, we observed that GAA treatment alone resulted in a histologically normal liver without evidence of hepatosteatosis despite persistence of some abnormal biochemical parameters. This protection could result from the generation of creatine from the ingested GAA. Ethanol treatment for 6 wk exhibited changes in liver methionine metabolism and persistence of histological and biochemical defects as reported before. Further, when the rats were fed the GAA-supplemented ethanol diet, similar histological and biochemical changes as observed after 2 wk of combined treatment, including inflammation, macroand micro-vesicular steatosis and a marked decrease in the methylation index were noted. In addition, rats on the combined treatment exhibited increased liver toxicity and even early fibrotic changes in a subset of animals in this group. The worsening liver pathology could be related to the profound reduction in the hepatic methylation index, an increased accumulation of GAA and the inability of creatine generated to exert its hepato-protective effects in the setting of ethanol.CONCLUSION To conclude, prolonged exposure to a methyl consumer superimposed on chronic ethanol consumption causes persistent and pronounced liver damage. 展开更多
关键词 methyl balance S-ADENOSYLMETHIONINE S-ADENOSYLHOMOCYSTEINE Guanidinoacetate alcohol
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羧酸离子液体/氧气催化氧化芳甲醇 被引量:1
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作者 吴丰田 吴玲 谢宗波 《精细化工》 EI CAS CSCD 北大核心 2023年第3期689-696,共8页
在组合体系“1-乙基-3-甲基咪唑乙酸盐([EMIm][OAc])/O_(2)”作用下,以芳甲醇为原料,经氧化反应,合成了系列芳甲醛(酮)类化合物。通过对条件进行优化,得到适宜反应条件为:芳甲醇与1-乙基-3-甲基咪唑乙酸盐物质的量比为1∶1、O_(2)压力为... 在组合体系“1-乙基-3-甲基咪唑乙酸盐([EMIm][OAc])/O_(2)”作用下,以芳甲醇为原料,经氧化反应,合成了系列芳甲醛(酮)类化合物。通过对条件进行优化,得到适宜反应条件为:芳甲醇与1-乙基-3-甲基咪唑乙酸盐物质的量比为1∶1、O_(2)压力为0.20MPa、温度为130℃、时间为12h。在此条件下,实现了苯甲醛的克级规模制备,得到20种芳甲醛(酮),产率为62%~96%。提出了[EMIm][OAc]通过阴离子作用于苯甲醇,经O_(2)氧化,脱水得到苯甲醛的反应机理。 展开更多
关键词 离子液体 氧气 氧化 芳甲醇 芳甲醛 精细化工中间体
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甲醇作为甲基化试剂催化体系研究进展
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作者 杨东元 王斌 +1 位作者 崔新江 常春然 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2023年第6期1442-1452,共11页
甲醇是最小的含有碳氢氧的饱和有机分子,广泛应用于能源、化工以及有机合成等领域。通过氢转移的方法,将甲醇作为甲基化试剂,与胺、醇/酮以及烃类化合物耦合转化制备高值化的甲基化产品,是一项非常有意义的研究工作。氢转移反应过程的... 甲醇是最小的含有碳氢氧的饱和有机分子,广泛应用于能源、化工以及有机合成等领域。通过氢转移的方法,将甲醇作为甲基化试剂,与胺、醇/酮以及烃类化合物耦合转化制备高值化的甲基化产品,是一项非常有意义的研究工作。氢转移反应过程的机理主要包括:甲醇的催化脱氢制甲醛;甲醛与底物脱水获得不饱和键;不饱和键原位加氢获得最终的产物。总结了近年来甲醇作为甲基化试剂,通过氢转移的方法制备甲基化胺、醇/酮以及烃类化合物催化体系的发展,并重点介绍了基于贵金属与非贵金属的均相和多相反应体系。鉴于反应过程中甲醇催化脱氢和不饱和键加氢对反应活性和选择性的影响这一科学问题,通过配位结构/金属载体的相互作用的调控有可能制备高催化性能均相/多相催化反应体系,且多相非贵金属催化体系具有较好的工业化应用前景。 展开更多
关键词 甲醇 甲基化
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乙醇酸甲酯选择性氧化制备乙醛酸甲酯研究进展 被引量:1
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作者 王浩 赵国锋 路勇 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第1期104-113,共10页
乙醛酸甲酯在有机合成和化工生产中应用广泛,传统的制备方法存在成本高、效率低、易造成环境污染等缺点.乙醇酸甲酯是煤基合成气经草酸二甲酯加氢制乙二醇工艺的中间产物且可高选择性控制合成,以其为原料选择性氧化制备乙醛酸甲酯具有... 乙醛酸甲酯在有机合成和化工生产中应用广泛,传统的制备方法存在成本高、效率低、易造成环境污染等缺点.乙醇酸甲酯是煤基合成气经草酸二甲酯加氢制乙二醇工艺的中间产物且可高选择性控制合成,以其为原料选择性氧化制备乙醛酸甲酯具有较好的工业应用前景,但目前为止,研究较为有限.本文综述了乙醛酸甲酯的应用、传统制备方法及乙醇酸甲酯氧化法的研究现状,也总结了相关醇类(如乙醇)选择性氧化制醛酮的研究进展. 展开更多
关键词 乙醇酸甲酯 乙醛酸甲酯 选择氧化 分子氧 醇氧化
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甲基封端烯丙醇聚醚的合成 被引量:1
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作者 房连顺 《精细石油化工进展》 CAS 2023年第3期15-19,共5页
以烯丙醇聚醚(A-550)、NaOH和氯甲烷(CH3Cl)为主要原料,采用Williamson醚化反应合成甲基封端烯丙醇聚醚。通过单因素试验和正交试验,确定了最佳合成工艺条件:n(NaOH)∶n(A-550)=1.4∶1,n(CH3Cl)∶n(A-550)=1.3∶1,反应温度60℃,反应时间... 以烯丙醇聚醚(A-550)、NaOH和氯甲烷(CH3Cl)为主要原料,采用Williamson醚化反应合成甲基封端烯丙醇聚醚。通过单因素试验和正交试验,确定了最佳合成工艺条件:n(NaOH)∶n(A-550)=1.4∶1,n(CH3Cl)∶n(A-550)=1.3∶1,反应温度60℃,反应时间6 h,四丁基溴化铵质量分数0.15%,分2次加碱。在此基础上进行3次重复性试验,平均封端率96.01%。对原料和产物进行红外光谱分析,产物中的羟基明显减少,甲基封端效果良好。 展开更多
关键词 烯丙醇聚醚 甲基封端 醚化 四丁基溴化铵 相转移催化
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高脂饮食诱导的小鼠NAFLD模型肝组织中m6A甲基化修饰表达谱分析
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作者 刘君君 逯素梅 +2 位作者 张炳杨 李永清 马万山 《上海交通大学学报(医学版)》 CAS CSCD 北大核心 2023年第10期1227-1235,共9页
目的·利用微阵列芯片技术检测高脂饮食诱导的小鼠非酒精性脂肪性肝病(non-alcoholic fatty liver disease,NAFLD)模型中肝组织mRNA的m6A甲基化修饰和基因表达的变化。方法·以6~8周龄雄性C57BL/6J小鼠为实验动物,高脂饲料喂养1... 目的·利用微阵列芯片技术检测高脂饮食诱导的小鼠非酒精性脂肪性肝病(non-alcoholic fatty liver disease,NAFLD)模型中肝组织mRNA的m6A甲基化修饰和基因表达的变化。方法·以6~8周龄雄性C57BL/6J小鼠为实验动物,高脂饲料喂养16周诱导建立NAFLD模型(高脂组,n=10);另设基础组(n=10)为对照,给予含10%脂肪的基础饲料喂养。苏木精-伊红(hematoxylin-eosin,H-E)染色评估小鼠肝组织病理改变,判断NAFLD模型是否构建成功。运用甲基化RNA免疫共沉淀技术(methylated RNA immunoprecipitation,MeRIP)和微阵列测序技术(microarray表达谱分析)检测2组小鼠肝组织中mRNA的m6A甲基化和表达水平变化。结果·基础组小鼠肝脏呈鲜红色,少见脂肪沉积;高脂组小鼠肝脏边界黄润,H-E染色可见肝细胞中脂滴弥漫浸润且相互融合,提示高脂饲料诱导的NAFLD模型构建成功。MeRIP-微阵列芯片检测结果显示,与基础组相比,高脂组小鼠肝脏中共有320个基因m6A甲基化修饰水平变化显著(P<0.05且变化倍数>1.5),其中有108个上调基因和212个下调基因。将组间m6A甲基化水平差异显著的基因与mRNA差异表达基因取交集,发现有163个基因m6A甲基化水平和mRNA表达水平均差异显著。结论·高脂饮食诱导的小鼠NAFLD模型中肝组织mRNA的m6A修饰变化显著,且该变化与mRNA的基因表达有关。 展开更多
关键词 非酒精性脂肪性肝病 m6A甲基化修饰 mRNA 表观转录组学
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