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Metabonomic analysis of plasma biochemical changes in pyrexia rats after treatment with Gegenqinlian decoction,aspirin and itraconazole by UHPLC-FT-ICR-MS 被引量:6
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作者 Ting liu ruiyun li +2 位作者 Yue Cui Zhiguo Yu Yunli Zhao 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期581-587,共7页
A metabonomic approach involving an ultrahigh-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry(UHPLC-FT-ICR-MS)was used to investigate the changes in the endo... A metabonomic approach involving an ultrahigh-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry(UHPLC-FT-ICR-MS)was used to investigate the changes in the endogenous metabolites in the plasma of rats with yeast-induced pyrexia treated with Gegenqinlian decoction(GQLD),aspirin and itraconazole.The differences in the small molecule profiles of treatment using traditional Chinese medicine,etiological treatment and symptomatic treatment were elucidated.Thirty-six plasma metabolites were identified or putatively identified,and the effects of the three medicines on the thirty-six metabolites were studied.Their metabolic pathways indicated that GQLD,aspirin and itraconazole ameliorated the rats with yeast-induced pyrexia predominantly by regulating the metabolisms of phospholipid,sphingolipid,fatty acid oxidation,fatty acid amides,amino acid and glycerolipid in vivo.The pharmacodynamics and metabonomic results showed that the three medicines exhibited the therapeutic effects on pyrexia by regulating the perturbations of multiple metabolisms.The study provided a scientific basis for an in-depth understanding of the therapeutic effects of GQLD,aspirin and itraconazole on rats with yeast-induced pyrexia. 展开更多
关键词 Gegenqinlian decoction ASPIRIN ITRACONAZOLE PYREXIA UHPLC-FT-ICR-MS Metabonomic
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新型高效Bronsted酸性离子液体催化剂体系催化烯烃齐聚反应 被引量:3
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作者 王国芹 宋河远 +2 位作者 李瑞云 李臻 陈静 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第6期1110-1120,共11页
烯烃齐聚是重要的化工反应之一,是指低碳烯烃在催化剂存在下发生聚合反应,生成一个或多个单体重复相连的化合物过程.烯烃齐聚反应是一种碳链增长过程,是生成线性α-烯烃的重要过程.齐聚反应主要生成单体的二聚、三聚、四聚或五聚物等低... 烯烃齐聚是重要的化工反应之一,是指低碳烯烃在催化剂存在下发生聚合反应,生成一个或多个单体重复相连的化合物过程.烯烃齐聚反应是一种碳链增长过程,是生成线性α-烯烃的重要过程.齐聚反应主要生成单体的二聚、三聚、四聚或五聚物等低聚体,发生反应的单体主要是低碳烯烃如乙烯、丙烯、正丁烯和异丁烯等.烯烃齐聚产物应用十分广泛,可以用于合成环境友好的液体燃料、长链烷烃润滑油、表面活性剂、增塑剂、汽油柴油添加剂等重要化工产品,同时齐聚产物本身亦是重要的化工中间体和化学试剂.烯烃齐聚反应研究的重点内容是开发新颖高效的催化剂,以满足不同需要,而应用Br?nsted酸性功能化离子液体作为催化剂用于齐聚反应的报道较少.本文考察了新型高效催化剂体系(Br?nsted酸性离子液体作为主催化剂,三辛基甲基氯化铵作为助剂)对烯烃齐聚反应的催化性能.合成的Br?nsted酸性离子液体通过红外光谱、紫外可见光谱、~1H核磁共振和^(13)C核磁共振等进行系列表征,并进一步分析其结构与酸度的关系.结果表明,在相同的反应条件下,Br?nsted酸性离子液体[HIMBs]HSO_4对烯烃齐聚反应具有最好的催化活性.本文考察了不同离子液体、离子液体用量、不同助剂、助剂用量、反应时间、反应压力、反应温度和不同溶剂等因素对反应的影响,得到了最佳反应条件:催化剂体系为[HIMBs]HSO_4与三辛基甲基氯化铵,[HIMBs]HSO4/异丁烯摩尔比为25%,[HIMBs]HSO_4/助剂(三辛基甲基氯化铵)摩尔比为20:1,140 ℃,8 h,反应起始压力为2.0 MPa,无添加溶剂(离子液体本身作催化剂和溶剂).在最佳反应条件下对反应物进行了拓展,并研究了催化剂体系的循环使用情况.在最佳反应条件下,异丁烯齐聚反应中反应物转化率为83.21%,三聚物选择性高达35.80%,二聚物选择性为52.02%,四聚物选择性为3.14%.结果表明,本文提出的催化剂体系对烯烃齐聚反应具有较好的催化性能.同时,催化剂体系可以通过静置分层与产物分离,并进行循环使用.根据以往的报道和反应产物分布,推测了烯烃齐聚反应机理.烯烃齐聚反应为酸催化反应,生成碳正离子中间体进行碳链增长,生成齐聚产物. 展开更多
关键词 Bronsted酸性离子液体 烯烃 齐聚反应 催化反应 共催化剂
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Composition analysis and antioxidant activities of the Rhus typhina L.stem 被引量:2
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作者 Ting liu Zhaoqin li +3 位作者 ruiyun li Yue Cui Yunli Zhao Zhiguo Yu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第5期332-338,共7页
The present investigation reports the chemical composition of the Rhus typhina L. stem identified via mass spectrometry and NMR as gallic acid, 1-O-galloyl-β-D-glucose, tryptophan, scopolin, methyl gallate, fustin, q... The present investigation reports the chemical composition of the Rhus typhina L. stem identified via mass spectrometry and NMR as gallic acid, 1-O-galloyl-β-D-glucose, tryptophan, scopolin, methyl gallate, fustin, quercetin, rutin, and 1,2,3,4,6-penta-O-galloyl-β-D-glucose. The antioxidant properties and the chemical composition contents of the R. typhina L. stem grown in different regions in China were determined. To determine the antioxidant activity, a total phenolic content analysis, 2, 2-diphenyl-1-picrylhydrazyl radical scavenging activity assay, ferric reducing antioxidant power assay, and β-carotene linoleic acid model system were conducted. The results showed that the Rhus typhina L. stem possessed high antioxidant capacities due to its high phenolic content. The contents of the nine isolated compounds were determined by UPLC-ESI-MS/MS. The calibration curves of the nine isolated compounds were linear within the concentration range and the average recoveries were high. The result showed that 1-Ogalloyl-β-D-glucose, gallic acid, methyl gallate, and 1,2,3,4,6-penta-O-galloyl-β-D-glucose could be the compounds mainly responsible for the antioxidant capacity of the R. typhina L. stem. This reveals that the R. typhina L. stem is a good source of antioxidants. 展开更多
关键词 RHUS typhina L. STEM ANTIOXIDANT activity CHEMICAL COMPOSITION UPLC-ESI-MS/MS
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早寒武纪清江丝菌牵出硫酸盐还原菌与地球环境协同演化 历史
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作者 崔琳浩 朱珂磊 +13 位作者 李瑞云 常超 吴来源 刘伟 傅东静 刘沛余 邱浩 唐国强 李秋立 Robert R.Gaines 陶昕 王寅 李金华 张兴亮 《Science Bulletin》 SCIE EI CAS CSCD 2024年第10期1486-1494,共9页
Sulfate reduction is an essential metabolism that maintains biogeochemical cycles in marine and terrestrial ecosystems.Sulfate reducers are exclusively prokaryotic,phylogenetically diverse,and may have evolved early i... Sulfate reduction is an essential metabolism that maintains biogeochemical cycles in marine and terrestrial ecosystems.Sulfate reducers are exclusively prokaryotic,phylogenetically diverse,and may have evolved early in Earth’s history.However,their origin is elusive and unequivocal fossils are lacking.Here we report a new microfossil,Qingjiangonema cambria,from518-million-year-old black shales that yield the Qingjiang biota.Qingjiangonema is a long filamentous form comprising hundreds of cells filled by equimorphic and equidimensional pyrite microcrystals with a light sulfur isotope composition.Multiple lines of evidence indicate Qingjiangonema was a sulfate-reducing bacterium that exhibits similar patterns of cell organization to filamentous forms within the phylum Desulfobacterota,including the sulfate-reducing Desulfonema and sulfide-oxidizing cable bacteria.Phylogenomic analyses confirm separate,independent origins of multicellularity in Desulfonema and in cable bacteria.Molecular clock analyses infer that the Desulfobacterota,which encompass a majority of sulfate-reducing taxa,diverged~2.41 billion years ago during the Paleoproterozoic Great Oxygenation Event,while cable bacteria diverged~0.56 billion years ago during or immediately after the Neoproterozoic Oxygenation Event.Taken together,we interpret Qingjiangonema as a multicellular sulfate-reducing microfossil and propose that cable bacteria evolved from a multicellular filamentous sulfate-reducing ancestor.We infer that the diversification of the Desulfobacterota and the origin of cable bacteria may have been responses to oxygenation events in Earth’s history. 展开更多
关键词 CAMBRIAN Qingjiangonema Sulfate-reducing bacteria Cable bacteria Qingjiang biota Black shale
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Different Laboratory Abnormalities in COVID-19 Patients with Hypertension or Diabetes
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作者 Xiaojun Wu Tong Wang +13 位作者 Yilu Zhou Xiaofan liu Hong Zhou Yang Lu Weijun Tan Mingli Yuan Xuhong Ding Jinjing Zou ruiyun li Hailing liu Rob MEwing Yi Hu Hanxiang Nie Yihua Wang 《Virologica Sinica》 SCIE CAS CSCD 2020年第6期853-856,共4页
Dear Editor,The pandemic of COVID-19,a disease caused by severe acute respiratory syndrome coronavirus 2(SARS-Co V-2;previously known as 2019-n Co V),has placed an enormous burden on health authorities in 213 countrie... Dear Editor,The pandemic of COVID-19,a disease caused by severe acute respiratory syndrome coronavirus 2(SARS-Co V-2;previously known as 2019-n Co V),has placed an enormous burden on health authorities in 213 countries and territories.At the time of writing,over 26 million cases have been recorded across the world,with more than 870 k associated deaths(www.worldometers.info/coronavirus/).World Bank warns COVID-19 pandemic risks dramatic rise in poverty,with the majority of economies expecting to suffer from falling levels of GDP in 2020. 展开更多
关键词 ACUTE RESPIRATORY authorities
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