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The Effect of Vineyard Cover Crop on Main Monomeric Phenols of Grape Berry and Wine in Vitis viniferal L. cv. Cabernet Sauvignon 被引量:11
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作者 XI Zhu-mei ZHANG Zhen-wen CHENG Yu-feng LI Hua 《Agricultural Sciences in China》 CAS CSCD 2010年第3期440-448,共9页
This study was conducted to determine the effect of cover crop inter-row in vineyard on main mono-phenol content of grape berry and wine. Three such cover crops, two perennial legumes (white clover and alfalfa) and ... This study was conducted to determine the effect of cover crop inter-row in vineyard on main mono-phenol content of grape berry and wine. Three such cover crops, two perennial legumes (white clover and alfalfa) and a perennial gramineous grass (tall fescue) were sown in vineyard. The main phenolic compounds of mature grape berry and wines vinified under the same conditions were extracted with ethyl acetate and diethyl ether and analyzed by high- performance liquid chromatography (HPLC) by comparing to soil tillage. A total of ten phenolic compounds were identified and quantified in the different grape berry and wines, including nonflavonoids (hydroxybenzoic and hydroxycinnamic acids) and flavonoids (flavanols and flavonols). The concentration of flavonoid compounds (409.43 to 538.63 mg kg^-1 and 56.16 to 81.30 mg L^-1) was higher than nonflavonoids (76.91 to 98.85 mg kg^-1 and 30.65 to 41.22 mg L^-1) for Cabernet Sauvignon grape and wine under different treatments, respectively. In the flavonoid phenolics, Catechin was the most abundant in the different grapes and wines, accounting for 74.94 to 79.70% and 48.60 to 50.62% of total nonanthocyanin phenolics quantified, respectively. Compared to soil tillage, the sward treatments showed a higher content of main mono-phenol and total nonanthocyanin phenolics in grapes and wines. There were significant differences between two cover crop treatments (tall fescue and white clover) and soil tillage for the content of benzoic acid, salicylic acid, caffeic acid, catechin, and total phenolics in the grape berry (P 〈 0.05 or P〈0.01). The wine from tall fescue cover crop had the highest gallic acid, caffeic acid and catechin. Cover crop system increased the total nonanthocyanin phenolics of grapes and wines in order of the four treatments: tall fescue, white clover, alfalfa, and soil tillage (control). Cover crop in vineyard increased total phenols of grape berry and wine, and thus improved the quality of wine evidently. 展开更多
关键词 VINEYARD cover crops inter-row Cabernet Sauvignon grape berry WINE monomeric phenols
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Recombinant Expression of the Monomeric B27 Lys Destripeptide Insulin Precursor( MIP) in Escherichia coli 被引量:1
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作者 陈婷 朱文凯 +3 位作者 张云龙 张敏敏 陈丽 陆昌瑞 《Journal of Donghua University(English Edition)》 EI CAS 2018年第1期43-46,共4页
Insulin controls hyperglycemia caused by diabetes,and virtually all treatments require exogenous insulin. The monomeric B27 Lys destripeptide insulin has 80% bioactivity of wild type. It is a potential drug for clinic... Insulin controls hyperglycemia caused by diabetes,and virtually all treatments require exogenous insulin. The monomeric B27 Lys destripeptide insulin has 80% bioactivity of wild type. It is a potential drug for clinic. But the yield of monomeric B27 Lys destripeptide insulin is limited, because monomeric B27 Lys destripeptide insulin precursor( MIP) was easily to form inclusion body,when MIP is expressed in E. coli. The precursor,MIP,is not only fused to an N-terminal HIS-small ubiquitin-related modifier( SUMO) tag,but also added five Arginine( 5 R) at the C-terminal,which can improve the solubility of the fusion protein. By this way,the yield of fusion protein has been up to 1. 45 mg/L cell culture.This work set up the foundation for the clinical application of B27 Lys destripeptide insulin. 展开更多
关键词 B27 Lys destripeptide insulin optimization monomeric B27 Lys destripeptide insulin precursor(MIP)
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A SIMPLE ACCESS TO UNSOLVATED MONOMERIC COMPLEXES OF EARLY LANTHANIDE IODIDES(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)VIA THE REACTION OF[(CH_3OCH_2CH_2C_5H_4)_2LnCl]_2 WITH NaI AND X-RAY CRYSTAL STRUCTURE OF THE LANTHANUM COMPLEX
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作者 Chang Tao QIAN Bing Wang Xiao Fan ZHENG Dao Li DENG Jie SUN Laboratory of Organometallic Chemistry,Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第9期841-844,共4页
(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)complexes have been synthesized by the reaction between NaI and[(CH_3OCH_2CH_2C_5H_4)_2LnCl]2 in THF;A single crystal X-ray study has shown that the lanthanum complex is an unsolvat... (CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)complexes have been synthesized by the reaction between NaI and[(CH_3OCH_2CH_2C_5H_4)_2LnCl]2 in THF;A single crystal X-ray study has shown that the lanthanum complex is an unsolvated monomer with lanthanum(Ⅲ)in a trigonal bipyramidal coordination geometry if the cyclopentadienyl ring is regarded as occupying a single polyhedral vertex. 展开更多
关键词 OCH Ln=La Nd)VIA THE REACTION OF CH3OCH2CH2C5H4 LN A SIMPLE ACCESS TO UNSOLVATED monomeric COMPLEXES OF EARLY LANTHANIDE IODIDES ND LA VIA NAI
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Effect of Citric Acid on the Total Monomeric Anthocyanins and Antioxidant Activity of Liquor Made from Unprocessed Purple Leafed TRFK 306 Kenyan Tea Clone
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作者 Emily C. Kilel John K. Wanyoko +1 位作者 Abdul K. Faraj Peninah Ngoda 《Food and Nutrition Sciences》 2019年第10期1191-1201,共11页
A study was conducted to find out the effect of citric acid on total monomeric anthocyanins and antioxidant activity of liquor made from unprocessed purple-leafed TRFK 306 Kenyan tea, brewed at various time/temperatur... A study was conducted to find out the effect of citric acid on total monomeric anthocyanins and antioxidant activity of liquor made from unprocessed purple-leafed TRFK 306 Kenyan tea, brewed at various time/temperature combinations. Most purple tea consumers usually brew the tea leaves then add some lemon juice before consuming it. Citric acid was used here to mimic the use of lemon juice. Documentation on the quality of such a brew is scanty and the effect of acid on its quality is equally scanty. The current study used brewing time/temperature combinations of 5, 10 and 15 minutes with 70&deg;C and 92&deg;C drinking water. Total monomeric anthocyanins were analysed using UV-1800 spectrophotometer (Shimadzu, Japan) while DDPH method was used to assay for antioxidant activity. Citric acid concentration of 0, 0.1% to 0.5% was used to check their effect on the brews with the highest total anthocyanins and antioxidant activity. The results showed that brewing temperature of 70&deg;C had 9.5 mg/L to 27.7 mg/L, with 5 minutes brewing time being the highest. Temperature of 92&deg;C had 37.5 mg/L to 92 mg/L with 5 minutes brewing time having the highest total monomeric anthocyanins. Antioxidant activity of 92&deg;C brewing temperature ranged from 90.7% to 92.0%. Total monomeric anthocyanins increased with increased citric acid concentration up to 0.3% before it decreases while for antioxidant activity, it decreased with addition of citric acid. It was concluded that for maximum anthocyanins extraction, 5 minutes brewing time is the best while ten minutes brewing time could give optimum antioxidant activity. 展开更多
关键词 TRFK 306 TOTAL monomeric Anthocyanins Antioxidant Activity Citric Acid BREWING Conditions
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Structural Aspects of Monomeric Platinum Coordination Complexes
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作者 Milan Melník Peter Mikus 《Materials Sciences and Applications》 2014年第8期512-547,共36页
This review covers structural parameters of almost two thousand monomeric Pt coordination complexes. The Pt is found in the oxidation states zero, +1, +2, +3 and +4, from which oxidation state +2 by far prevails. Ther... This review covers structural parameters of almost two thousand monomeric Pt coordination complexes. The Pt is found in the oxidation states zero, +1, +2, +3 and +4, from which oxidation state +2 by far prevails. There is a wide variety of donor atom ligands from uni-, bi-, ter- and tetradentate with over seventeen types of donor atoms, from which by far prevails P and N donor ligands and chlorine atom. The Pt(0) atoms are two-, three- and four-coordinated;Pt(I) and Pt(III) are only four-coordinated, Pt(II) are four- and five-coordinated, and Pt(IV) are five- and six-coor-dinated. About 10% of these complexes exist as isomers. Included are distortion (65%), cis-trans (30%), mixed isomers and ligand isomerism. The structural parameters are discussed in terms of the coordination about the platinum atom, and correlations are drawn between donor atom, bond length and interbond angles with attention to any trans-effect. 展开更多
关键词 STRUCTURE PLATINUM monomeric ISOMERS Trans-Effect
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SGCC successfully developed large-capacity sodium-sulfur monomeric battery
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《Electricity》 2009年第4期33-,共1页
Through many years' cooperation,SGCC and Shanghai Silicate Research Institute of Chinese Academy of Science successfully developed 650 ampere-hours capacity sodium-sulfur monomeric storage battery with the indepen... Through many years' cooperation,SGCC and Shanghai Silicate Research Institute of Chinese Academy of Science successfully developed 650 ampere-hours capacity sodium-sulfur monomeric storage battery with the independent intellectual property 展开更多
关键词 SGCC successfully developed large-capacity sodium-sulfur monomeric battery
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A study on carbon isotopes of C_(5-8) light hydrocarbon monomeric series of natural gas in main oil and gas bearing basins in China 被引量:3
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作者 戴金星 李鹏举 《Chinese Science Bulletin》 SCIE EI CAS 1995年第6期497-500,共4页
There have been many achievements in the research on carbon isotopes of alkane hydrocarbon gases in oil and gas bearing basins in China. Because of the limited molecular types and the simple molecular structures of C&... There have been many achievements in the research on carbon isotopes of alkane hydrocarbon gases in oil and gas bearing basins in China. Because of the limited molecular types and the simple molecular structures of C<sub>1-4</sub> alkane hydrocarbon gases, the information provided by these carbon isotopes is limited. C<sub>5-8</sub> light hydrocarbons are found more often in wet gas, and their molecules have more complex structures and 展开更多
关键词 carbon ISOTOPES of C5-8 light HYDROCARBON monomeric SERIES natural gas China.
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Carbon Isotopic Distribution Characteristics of Light Hydrocarbon Monomeric Series of Crude Oils in the Ordos Basin 被引量:1
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作者 张文正 裴戈 关德师 《Chinese Science Bulletin》 SCIE EI CAS 1993年第1期62-66,共5页
Abundant carbon isotopic information of single molecule can be obtained from the trace samples (chromatographic grade) on the basis of carbon isotopic on-line analytical technique developed in the late 1980s. This bri... Abundant carbon isotopic information of single molecule can be obtained from the trace samples (chromatographic grade) on the basis of carbon isotopic on-line analytical technique developed in the late 1980s. This brings the carbon isotopic study of the petroleum and natural gases into a new development stage. 展开更多
关键词 CARBON isotopes of light hydrocarbon monomeric SERIES distribution and evolutionary features the ORDOS Basin.
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Research progress of TCM monomer in treating diabetic kidney disease based on inflammatory mechanism
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作者 HAN Wen-long QIN Jia-ping +1 位作者 LIN Ke-xin LIU Qiang 《Journal of Hainan Medical University》 CAS 2024年第3期63-68,共6页
With the increasing morbidity of diabetes mellitus (DM), diabetic kidney disease (DKD) has become the major reason causing chronic kidney disease (CKD) and end-stage renal disease (ESRD) over the world. However, curre... With the increasing morbidity of diabetes mellitus (DM), diabetic kidney disease (DKD) has become the major reason causing chronic kidney disease (CKD) and end-stage renal disease (ESRD) over the world. However, current treating strategy is aiming at blood glucose controlling and renin-angiotensin system (RAS) restricting which can’t effectively preventing the development of DKD. Recent research indicating that low level of inflammatory and activation of immune system play a significant role in occurrence and progression of DKD. Understanding of inflammatory cascade and its mechanism is conducive to discern novel target of DKD and contributing to design new treating strategy based on anti-inflammatory. For the past few years, an increasing number of evidences proved that Tradit Chin Med (TCM) could delay the progression of ESRD on the basis of inflammatory. In this review, we overview the protective effect against DKD-based renal injury of TCM monomer, offering novel ideas in drug discovery and in mechanism-related research.sd. 展开更多
关键词 Diabetic kidney disease INFLAMMATION Monomer of Chinese traditional HERBS
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Photothermal biological effects of monomeric erythrocyte using optical tweezers
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作者 鲁浩 吴莹 +3 位作者 谢文菁 唐琦 韩彩芹 刘莹 《Chinese Optics Letters》 SCIE EI CAS CSCD 2019年第6期59-64,共6页
The changes of mechanical properties and biological activities of monomeric erythrocytes are studied using optical tweezers micromanipulation technology.Firstly,the mechanical properties of irradiated erythrocyte memb... The changes of mechanical properties and biological activities of monomeric erythrocytes are studied using optical tweezers micromanipulation technology.Firstly,the mechanical properties of irradiated erythrocyte membranes are obtained.Weaker power laser irradiation can delay the decay of the mechanical properties of erythrocytes and promote the biological activity of erythrocytes,while higher power laser irradiation damages erythrocytes.The stronger the laser irradiation is,the more obvious and rapid the damage will be.The temperature of the cell surface will be changed by regulating the laser power and irradiation time,so the biological functions of erythrocyte can be controlled.Secondly,the finite element simulation of the temperature change on the cell surface under the condition of laser irradiation is carried out using simulation software,and the precise temperature of the cell surface irradiated cumulatively by a laser with different powers is obtained.Finally,the processes of abscission,unfolding,and denaturation of hemoglobins in erythrocytes at different temperatures due to the photothermal effect are analyzed using the model.The mechanism of laser irradiation on the elasticity of erythrocyte membranes is also obtained. 展开更多
关键词 CHANGES of MECHANICAL properties monomeric erythrocytes is ALSO obtained
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EXAFS and FTIR structural characterization for the crystal of monomeric tetraphenylporphyrinato gadolinium:[Gd(TPP)acac 8H_2O.3TCB]
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作者 姜建壮 胡天斗 +2 位作者 谢经雷 李册 张静智 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1998年第5期425-429,共5页
The coordination number of the gadolinium atom and bond distances in the crystal of inonomeric porphyrinate,[Gd(TPP)acac-8H2O 3TCB] (TCB: 1,2,4-trichlorobenzene,acac: anion of acetylacetone),were determined by EXAFS m... The coordination number of the gadolinium atom and bond distances in the crystal of inonomeric porphyrinate,[Gd(TPP)acac-8H2O 3TCB] (TCB: 1,2,4-trichlorobenzene,acac: anion of acetylacetone),were determined by EXAFS method.The Gd atom is eight-coordinated to the four nitrogen atoms of a tetraphenylporphyrin ring,to the two oxygen atoms of one acetylacetonato anion and to two water molecules with Gd-N=0.232 nm,Gd-O=0.243 nm. 展开更多
关键词 EXAFS structure monomeric porphyrinate rare earth
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Changing the Air Parameters in the Cotton Pneumatic Transport Pipe
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作者 Sarimsakov Olimjon Sattarov Nurillo +1 位作者 Oripov Nodirbek Kholmirzaev Farhod 《Engineering(科研)》 CAS 2023年第2期68-74,共7页
This scientific article examines the issue of changes in the density and speed of the airflow in the pipeline pneumatic conveying equipment used in ginneries, analyzes the causes of changes in the density and speed of... This scientific article examines the issue of changes in the density and speed of the airflow in the pipeline pneumatic conveying equipment used in ginneries, analyzes the causes of changes in the density and speed of air. 展开更多
关键词 Pneumatic Transport Actual Pressure Vacuum monomeric Pressure VENTILATOR Cotton Cleaning
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Progress on traditional Chinese medicine in improving hepatic fibrosis through inhibiting oxidative stress 被引量:2
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作者 Zhen Li Jun-Feng Zhu Hao Ouyang 《World Journal of Hepatology》 2023年第10期1091-1108,共18页
Hepatic fibrosis is a common pathological process that occurs in the development of various chronic liver diseases into cirrhosis and liver cancer,characterized by excessive deposition of the extracellular matrix.In t... Hepatic fibrosis is a common pathological process that occurs in the development of various chronic liver diseases into cirrhosis and liver cancer,characterized by excessive deposition of the extracellular matrix.In the past,hepatic fibrosis was thought to be a static and irreversible pathological process.In recent years,with the rapid development of molecular biology and the continuous in-depth study of the liver at the microscopic level,more and more evidence has shown that hepatic fibrosis is a dynamic and reversible process.Therefore,it is particularly important to find an effective,simple,and inexpensive method for its prevention and treatment.Traditional Chinese medicine(TCM)occupies an important position in the treatment of hepatic fibrosis due to its advantages of low adverse reactions,low cost,and multi-target effectiveness.A large number of research results have shown that TCM monomers,single herbal extracts,and TCM formulas play important roles in the prevention and treatment of hepatic fibrosis.Oxidative stress(OS)is one of the key factors in the occurrence and development of hepatic fibrosis.Therefore,this article reviews the progress in the understanding of the mechanisms of TCM monomers,single herbal extracts,and TCM formulas in preventing and treating hepatic fibrosis by inhibiting OS in recent years,in order to provide a reference and basis for drug therapy of hepatic fibrosis. 展开更多
关键词 Hepatic fibrosis Oxidative stress Traditional Chinese medicine monomer Single herbal extract Traditional Chinese medicine formula
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Self-deposition for mesoporous carbon nanosheet with supercapacitor application 被引量:1
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作者 Juan Du Aibing Chen +1 位作者 Senlin Hou Xueqing Gao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第3期34-40,共7页
Porous carbon sheets have wide application prospects in many fields,especially in energy storage of supercapacitor due to the features combining both 2D structure and porous architectures.Herein,a self-deposition appr... Porous carbon sheets have wide application prospects in many fields,especially in energy storage of supercapacitor due to the features combining both 2D structure and porous architectures.Herein,a self-deposition approach is proposed to obtain N-doped mesoporous carbon nanosheets (N-MCNs),using 3-aminophenol (3-AF) as precursor and Mg(OH)_(2) sheet as hard template.This process realizes the direct carbon formation using 3-AF monomer as carbon precursor under the catalysis of hard template avoiding the polymerization and utilization of solvent.The mass ratio of 3-AF to Mg(OH)_(2) plays an important role in determining the pore structures and the resulting capacitance behavior.The results show that N-MCNs with a mass ratio of 3-AF and Mg(OH)_(2) of 1:1 have good electrochemical behavior for supercapacitors.This N-MCNs based electrode exhibits a high capacitance of 240 F·g^(-1)at 1 A·g^(-1),good rate performance(75.4%retention ratio at 20 A·g^(-1)),and high cycling stability with 98.3% initial capacitance retained after 10000 cycles.Symmetric supercapacitors on N-MCNs achieve energy density of 18.2 W·h·kg^(-1) and power density of 0.4 kW·kg^(-1) operated within a wide potential range of 0–1.6 V in 1.0 mol·L^(-1) Na_(2)SO_(4) solution,exhibiting its potential for electrode materials with high performance. 展开更多
关键词 Monomer self-deposition Mg(OH)_(2)catalysis Hard template Carbon nanosheet SUPERCAPACITOR
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北京化工大学和青岛黑猫新材料研究院成功开发高分散水性炭黑创新技术
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《合成橡胶工业》 CAS 北大核心 2023年第6期494-494,共1页
据北京化工大学新闻网2023年8月18日报道,2023年8月13日,由北京化工大学和青岛黑猫新材料研究院共同开发的“高分散水性炭黑的开发”项目通过了中国石油和化学工业联合会组织的科技成果鉴定,产品性能指标达到国际同类产品先进水平,这是... 据北京化工大学新闻网2023年8月18日报道,2023年8月13日,由北京化工大学和青岛黑猫新材料研究院共同开发的“高分散水性炭黑的开发”项目通过了中国石油和化学工业联合会组织的科技成果鉴定,产品性能指标达到国际同类产品先进水平,这是我国在高端色素炭黑领域的又一项突破。由来自国内科研院所、高等院校、生产企业、行业协会等单位的7位专家组成的鉴定委员会听取了北京化工大学和青岛黑猫新材料研究院所做的项目工作报告、技术研究开发报告、经济和社会效益分析报告等,审查了用户报告、检验报告、查新报告等资料并考察了生产现场。专家组认为该项目采用普通炭黑原料制成的高分散水性炭黑生产工艺合理、黑度高且性能稳定,无论是从产品制造还是从产品性能及质量稳定性方面均可替代国外高端产品且具备连续化生产能力。 展开更多
关键词 MONOMER COMPOUND Mooney viscosity forecast model
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Macrophage involvement in the pathological evolution of ulcerative colitis-associated colon cancer and progress of related traditional Chinese medicine drug interventions
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作者 Jun-Yu Ke Jin-Bin Song +11 位作者 Long Li Zhen-Fan He Zhuo-Jian Huang Zheng-Lin Liu Gui-Rong Chen Su-Ru Wen Heng-Li Zhou Hui-Lin Ma Qun Du Yong-Qiang Wu Yan-Wu Li Xin-Lin Chen 《Traditional Medicine Research》 2023年第8期37-52,共16页
Intestinal macrophages are essential players in intestinal inflammation and intestinal immune homeostasis.Intestinal macrophages have the ability to polarize into two distinct phenotypes based on various environmental... Intestinal macrophages are essential players in intestinal inflammation and intestinal immune homeostasis.Intestinal macrophages have the ability to polarize into two distinct phenotypes based on various environmental signals.These phenotypes include the typically activated pro-inflammatory M1 phenotype and the alternatively activated anti-inflammatory M2 phenotype.Under normal circumstances,intestinal macrophages prevent inflammatory damage to the gut.However,when genetic and environmental factors influence the polarization of intestinal macrophages,it can lead to an imbalance in M1/M2 macrophage activation and subsequently an imbalance in the control of intestinal inflammation.It transforms physiological inflammation into pathological intestinal damage.In patients with ulcerative colitis-associated cancer(UC-CRC),intestinal inflammatory disorders are closely associated with intestinal M1/M2 macrophage polarization imbalance.Consequently,restoring the polarization equilibrium of M1/M2 macrophages might be an evidence of traditional Chinese medicine in the treatment of UC-CRC,the pivotal role o effective measure to prevent and treat UC-CRC.This paper aims to examine the clinicalf macrophage polarization in UC-CRC pathogenesis,and the potential mechanisms of traditional Chinese medicine in regulating macrophage polarization to treat UC-CRC.Our goal is to provide novel insights into the clinical practice,basic research,and drug development of UC-CRC. 展开更多
关键词 ulcerative colitis ulcerative colitis-associated cancer macrophage polarization herbal compound herbal monomer signaling pathway
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Low Cost Process for Phenolic Compounds Extraction from Cabernet Sauvignon Grapes (<i>Vitis vinifera</i>L. cv. Cabernet Sauvignon). Optimization by Response Surface Methodology 被引量:1
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作者 Youssef El Hajj Nicolas Louka +1 位作者 Catherine Nguyen Richard G. Maroun 《Food and Nutrition Sciences》 2012年第1期89-103,共15页
Phenolic compounds are naturally extracted molecules used nowadays for several industrial applications such as food preservatives and neutraciticals;thus industrial needs are in constant growth. Optimization of phenol... Phenolic compounds are naturally extracted molecules used nowadays for several industrial applications such as food preservatives and neutraciticals;thus industrial needs are in constant growth. Optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from grape berries using response surface methodology was here achieved. Cabernet Sauvignon (CS) wine grapes (Vitis vinifera L. cv. Cabernet Sauvignon) are a rich source of anti-radical phe- nols, extractable as dietary supplements. However, efficiency of extraction strongly depends on specific experimental conditions. In this work, the comparison between two extraction mixtures, Acetone/Water (A/W) and Methanol/Water (M/W) and the effects of three critical variables—Extraction Time (between 8 and 88 h), Extraction Temperature (between 1?C and 35?C) and Solvent Content (between 63% and 97%)—on Phenolic Compounds Yield (PCY) and Monomeric Anthocyanins Yield (MAY) were studied using Response Surface Methodology (RSM). Process conditions maximizing the PCY were found to be 87% A/W solvent content, after 88 h incubation at 26?C, and those of the MAY were found to be 97% M/W solvent content, after 8 h incubation at 1?C. In addition, chromatographic profiles of extracts showed very different affinities of the phenolic compounds families to the experimental conditions employed. This process advantages are: low percentage of organic solvent used, high quality of extracted molecules thanks to low temperature treatment, very low energy consumption and low cost of needed machinery. At industrial scale, it may be used as promising technique for the extraction of bioactive compounds from plant or byproduct material such as from wine or grape juice industries. 展开更多
关键词 Phenolic Compounds monomeric Anthocyanins EXTRACTION OPTIMIZATION Grape Time Solvent Temperature
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Antioxidants from Syrah Grapes (<i>Vitis vinifera L</i>.<i>cv</i>. <i>Syrah</i>). Extraction Process through Optimization by Response Surface Methodology
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作者 Youssef El Hajj Espérance Debs +2 位作者 Catherine Nguyen Richard G. Maroun Nicolas Louka 《Food and Nutrition Sciences》 2013年第12期1209-1220,共12页
In this work, optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from Syrah (Sy) wine grapes (Vitis vinifera L. cv. Syrah) using response surface methodology was conducted. The comparis... In this work, optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from Syrah (Sy) wine grapes (Vitis vinifera L. cv. Syrah) using response surface methodology was conducted. The comparisons between two extraction mixtures, Acetone/Water (A/W) as well as Methanol/Water (M/W) and the effects of three critical variables, Extraction Time (between 8 and 88 h), Extraction Temperature (between 1℃ and 35℃) and Solvent Content (between 63% and 97%), on Phenolic Compounds Yield (PCY), Monomeric Anthocyanins Yield (MAY) and the DPPH Free Radical Inhibition Potential (DFRIP) were studied. The highest PCY was obtained in 63% A/W solvent content after 88 h incubation at 35℃. The highest MAY was acquired in 97% M/W solvent content after 8 h incubation at 17℃. The highest DFRIP of the extract was attained using 97% A/W solvent content after 16 h incubation at 35℃. The low cost of this process, on economic and environmental levels, could lead to interesting applications on an industrial scale. It could be used to obtain bioactive phytochemicals from direct material or byproducts for either therapeutic or nutritional purposes. 展开更多
关键词 Phenolic Compounds monomeric Anthocyanins Antiradical SCAVENGING Potential Extraction OPTIMIZATION GRAPE Time Solvent and Temperature
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Studies on a Cationically Modified Quaternary Ammonium Salt of Lignin 被引量:18
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作者 YANG Ai-li JIANG Wen-ju 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第4期479-482,共4页
A new quaternary ammonium salt monomer was synthesized and a quaternary amination of lignin( noted as QL), with the monomer was carried out by grafting copolymerization. The products were characterized by Fourier Tr... A new quaternary ammonium salt monomer was synthesized and a quaternary amination of lignin( noted as QL), with the monomer was carried out by grafting copolymerization. The products were characterized by Fourier Transform Infrared spectroscopy( FTIR). The experimental results indicate that the yield of the monomer was 99.06%, and the conversion of the monomer and the grafting yield of QL were 93.69% and 185.78%, respectively. The feasibility of QL as the flocculant to be applied in color removal of five artificial dyes, erioehrome black T(dye A), gongo red(dye B ), direct fast black G (dye C ), cuprofix blue green B (dye D ), and acid black ATT (dye E ) was examined. Results show that OL exhihits the favorable flocculation nerformance and high stability. 展开更多
关键词 Quaternary ammonium salt of lignin(QL) Cationic monomer Grafting copolymerization FLOCCULATION
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Research on a novel composite gel system for CO_2 breakthrough 被引量:7
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作者 Hou Yongli Xiang'an 《Petroleum Science》 SCIE CAS CSCD 2010年第2期245-250,共6页
A composite gel was prepared for plugging CO2 channeling, which is a serious problem for enhanced oil recovery with CO2. A composite gel which is one of the materials for successful control of CO2 channeling during CO... A composite gel was prepared for plugging CO2 channeling, which is a serious problem for enhanced oil recovery with CO2. A composite gel which is one of the materials for successful control of CO2 channeling during CO2 injection process was studied in this paper. SEM and nano particle size analysis were used to describe this material’s microstructure. Its effect on CO2 channeling control was evaluated with core flow experiments. Both the rheological test and core plugging experiments indicated that both acrylamide monomer concentration and reaction pressure had positive influences on gel properties. The gel system with an acrylamide monomer concentration of 2% and 5% sodium silicate was proved to have excellent strength, elastic and plugging efficiency, which confirmed huge development potential and wide application of the composite gel system. The high-pressure acid environment arising from the CO2 injection not only reacts with solid silicate to form silicic acid gel, but also facilitates efficient polymerization. 展开更多
关键词 Enhanced oil recovery CO2 CHANNELING composite gel acrylamide monomer
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