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组分分析法研究温拌橡胶沥青的降粘机理 被引量:5
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作者 李培国 《公路工程》 北大核心 2015年第1期249-252,260,共5页
选用目前应用最为广泛的两种温拌剂:Sasobit和Evotherm,从微观角度出发,通过组分试验和差热试验对加入这两种温拌剂的温拌橡胶沥青的化学组分进行分析,进而研究其降粘机理,研究结果为温拌橡胶沥青的降粘机理提供了理论基础,促进了温拌... 选用目前应用最为广泛的两种温拌剂:Sasobit和Evotherm,从微观角度出发,通过组分试验和差热试验对加入这两种温拌剂的温拌橡胶沥青的化学组分进行分析,进而研究其降粘机理,研究结果为温拌橡胶沥青的降粘机理提供了理论基础,促进了温拌橡胶沥青的推广使用。 展开更多
关键词 温拌橡胶沥青 组分实验 差热试验 降粘机理
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海藻酸钠对鸟粪石结晶的影响及机理研究 被引量:10
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作者 韦林 洪天求 +2 位作者 李如忠 张强 陈天虎 《中国环境科学》 EI CAS CSSCI CSCD 北大核心 2017年第8期2941-2946,共6页
鸟粪石结晶沉淀法回收剩余污泥中磷工艺具有良好应用前景,然而污泥中的一些有机物,特别是胞外聚合物(EPS)将对鸟粪石结晶产生一定的影响.海藻酸钠(SA)在物化性质上接近于EPS,为较深入地探究此影响机理,以SA作为EPS的代用化合物采用恒组... 鸟粪石结晶沉淀法回收剩余污泥中磷工艺具有良好应用前景,然而污泥中的一些有机物,特别是胞外聚合物(EPS)将对鸟粪石结晶产生一定的影响.海藻酸钠(SA)在物化性质上接近于EPS,为较深入地探究此影响机理,以SA作为EPS的代用化合物采用恒组分、恒p H实验来考察EPS对鸟粪石结晶的影响,并借助红外光谱(FTIR)和X射线光电子能谱(XPS)分析来探讨SA与鸟粪石晶体之间的作用机理.结果表明,在SA浓度0~250mg/L范围内,随其浓度的增大鸟粪石结晶生长速率降低,鸟粪石晶体的尺寸有所减小,其原因是海藻酸阴离子吸附并掩蔽鸟粪石表面生长活性点上阻碍晶体生长.这种吸附作用是由鸟粪石表面Mg2+、磷酸羟基团(POH)分别与SA中COOH、C=O、COC键合共同引起的,而鸟粪石表面的NH_4^+并未参与反应. 展开更多
关键词 鸟粪石 海藻酸钠 组分实验 晶体生长
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Preparation and coking properties of coal maceral concentrates 被引量:13
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作者 Zhang Lei Liu Wenli Men Dongpo 《International Journal of Mining Science and Technology》 SCIE EI 2014年第1期93-98,共6页
The concentrates with different maceral contents were obtained from Kailuan coking coals with different coal ranks(Ro;ranvarying from 0.88%to 1.73%)by float–sink separation in lab.Then these concentrates were charact... The concentrates with different maceral contents were obtained from Kailuan coking coals with different coal ranks(Ro;ranvarying from 0.88%to 1.73%)by float–sink separation in lab.Then these concentrates were characterized by proximate analysis,ultimate analysis,petrography analysis and coking index determination.The results show that the vitrinite is characterized as nature of lower carbon content,higher hydrogen content,higher volatile matter and stronger caking property compared to inertinite.The relationships between variation rate of volatile matter and maximum volatile matter and coal ranks are identified,and a linear model is developed for fast determination of the maceral contents.Compared to inertinite-rich concentrate,the blending ratio of vitrinite-rich concentrate is increased by 13%,which is considered to be a potential technique based on maceral separation for expanding the coking coal resources. 展开更多
关键词 Vitrinite Inertinite Properties Coking coal Maceral separation
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Physicochemical Characterization of Surface Water of the Area of Gafsa 被引量:1
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作者 R. Chraiti M. Raddaoui 《Journal of Environmental Science and Engineering》 2010年第10期16-21,共6页
Water exploits an essential part in all the durable development, the exploitation of this natural resource, its management and its position, its mineralization, its underground course and the mode o fits resurgence. T... Water exploits an essential part in all the durable development, the exploitation of this natural resource, its management and its position, its mineralization, its underground course and the mode o fits resurgence. The area of Gafsa is known by its very important hydrous potential which is geographically in the zone of transition between central Tunisia and the Saharan platform, these two great fields are separated by the fault of Gafsa which plays an important part in the structuring of the basins of the area, the hydrous resources of Gafsa make subsoil water the principal source of supply water, in the absence of an important network of surface. The zones of studies present requirements out of water which do not cease growing with the progress of the industrial activities and the concentration of the agricultural activities: The objective of this work is to analyze the water of the various zones of the area of Gafsa and to treat it to make it possible most drinkable. The analyzes like measurement of pH, measurement of electric conductivity and measurement of dry residue were made in the laboratory of the chemical group of Mdhila in Tunisia and in laboratory of Ion exchanger Materials of Vitry in France, the processes of treatment as opposite osmosis are also programmed in this same laboratory. The results are very encouraging to start the study and the design of a station of potabilisation of water in the area of Gafsa. 展开更多
关键词 Durable development the area of Gafsa hydrous potential to analyze to treat dry residue potabilisation
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Transcriptional diversity of DMRT1(dsx-and mab3.related transcription factor1)in human testis
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作者 Han Hua Cheng Ming Ying +3 位作者 Yi Hao Tian Yiqing Guo Ken McElreavey Rong Jia Zhou 《Cell Research》 SCIE CAS CSCD 2006年第4期389-393,共5页
Recent advances in the evolutionary genetics of sex determination indicate that the only molecular similarity in sex determination found so far among phyla is between the fly doublesex, worm mab-3 and vertebrate DMRTI... Recent advances in the evolutionary genetics of sex determination indicate that the only molecular similarity in sex determination found so far among phyla is between the fly doublesex, worm mab-3 and vertebrate DMRTI(dsx- and mab3-related transcription factor 1)/DMY genes. Each of these factors encodes a zinc-finger-like DNA-binding motif, DM domain. Insights into the evolution and functions of human DMRT1 gene could reveal evolutionary mechanisms of sexual development. Here we report the identification and characterization of multiple isoforms of human DMRT1 in the testis. These transcripts encode predicted proteins with 373,275 and 175 amino acids and they were generated by alternative splicing at 3' region. Expression level of DMRTla is higher than those of both DMRTlb and c, and the DMR Tlc expression was the lowest in testis, based on comparisons of mean values from real-time fluorescent quantitative RT-PCR analysis. Both DMRTlb and c result from exonization of intronic sequences, including the exonization of an Alu element. A further search for Alu elements within the DMRT1 gene demonstrated that all 99 Alu elements are non-randomly distributed among the non-coding regions on both directions. These new characteristics of DMRT1 would have an important impact on the evolution of sexual development mechanisms. 展开更多
关键词 evolution alternative splicing DOUBLESEX sex differentiation
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Study on the network delay of periodic information in the NCS based on EPA
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作者 刘宁 《High Technology Letters》 EI CAS 2009年第4期349-355,共7页
The network delay of the periodic messages transmission in the network control system (NCS) based on Ethemet for plant automation (EPA) is analyzed from the theoretical and experimental perspective in this paper. ... The network delay of the periodic messages transmission in the network control system (NCS) based on Ethemet for plant automation (EPA) is analyzed from the theoretical and experimental perspective in this paper. The composition and the characteristics of the network delay of EPA periodic messages transmission in a subnet is studied through analyzing the information transmission regularity and EPA deterministic scheduling mechanism. On this basis, the queuing delay at communication schedule management entity (EPA _ CSME) that is the most important component of network delay is analyzed, during which the formulas for the queuing delay of periodic messages and other real time parameters are proposed. Furthermore, an experiment is developed to test each component of network delay of periodic messages transmission in a EPA subnet. According to the experimental and the theoretical analysis, the conclusion is drawn that the delay during which the periodic messages wait for the periodic messages transmission time slice is the main factor that causes considerable network delay, and improvement method is presented. 展开更多
关键词 Ethernet for plant automation (EPA) network control system (NCS) periodic rues- sages network delay
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Corner forming of AZ61A magnesium alloy tube within warm hydroforming
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作者 胡蓝 韩聪 +3 位作者 何祝斌 汤泽军 刘钢 苑世剑 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第2期227-231,共5页
The comers with small radii on cross sections are crucial for forming hydroformed components with polygonal sections. In this paper, warm hydroforming experiments of AZ61A magnesium alloy tubes were cartied out to stu... The comers with small radii on cross sections are crucial for forming hydroformed components with polygonal sections. In this paper, warm hydroforming experiments of AZ61A magnesium alloy tubes were cartied out to study the forming regularity of round comers by using a demonstration part with square sections. Effects of temperature on radius forming, thinning ratio distribution and microstructure were revealed and a component with relative outer corner radius of 3.0 was obtained by warm hydroforming at 240℃. The minimum thickness of the formed square section was located in the transition position between the corner and the straight wall. The thinning ratio of the round corner increased with the increase of forming temperature. Fotmability of the magnesium tube was improved by raising temperature under the effect of dynamic recrystallization at 240℃. 展开更多
关键词 warm hydroforming magnesium alloy thickness distribution
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Distribution of electric field for carbon nanotube assembly: Experiments (II)
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作者 Soongeun KWON Soo-Hyun KIM +2 位作者 Kwang-ho KIM Myung-chang KANG Hyung-woo LEE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第A01期121-125,共5页
The distribution effect of electric field on the alignment and attachment of carbon nanotubes (CNTs) were investigated. The experimental results were compared with the simulation results according to three different... The distribution effect of electric field on the alignment and attachment of carbon nanotubes (CNTs) were investigated. The experimental results were compared with the simulation results according to three different shaped electrodes. In previous simulation, the round shaped electrodes were expected to be more effective for aligning and attaching a single CNT between two electrodes than conical or rectangular shaped electrodes. To verify the simulation results, three different shaped electrodes were introduced and a single multi-walled carbon nanotube (MWNT) was attached. The optimal conditions for aligning and attaching MWNTs such as the frequency, applied voltage and concentration of MWNTs solution were investigated. Through repeated experiments, frequency of 100 kHz-10 MHz, applied voltage of 0.3-1.3 V^s/~m, concentration of 5 ktg/mL in MWNTs solution were obtained as a possible condition range to attach MWNTs. Under these conditions, the yield of MWNTs attachment between two electrodes was up to 70%. In previous simulation, furthermore, it was verified that the size of the stable or quasi-stable region made CNTs aligned and attached on different shaped electrodes from the comparison of the experimental and simulation results. Most single MWNT attachment was accomplished on the round shaped electrodes. 展开更多
关键词 carbon nanotubes dielectrophoresis round shaped electrode simulation
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荆宝煤矿回采巷道顶板淋水治理措施 被引量:4
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作者 郭宁远 《江西煤炭科技》 2020年第3期195-197,202,共4页
荆宝煤矿三采区3#联络巷在掘进过程中顶板淋水严重,围岩稳定性较差,影响矿井的正常安全生产。本文采用打钻取芯、实验室力学及矿物组分测试、现场勘探的手段对顶板淋水进行了研究,并提出了相应的治理措施,工程监测结果表明该措施对巷道... 荆宝煤矿三采区3#联络巷在掘进过程中顶板淋水严重,围岩稳定性较差,影响矿井的正常安全生产。本文采用打钻取芯、实验室力学及矿物组分测试、现场勘探的手段对顶板淋水进行了研究,并提出了相应的治理措施,工程监测结果表明该措施对巷道顶板淋水现象控制效果较好,围岩稳定性大幅提高。 展开更多
关键词 顶板淋水 围岩稳定性 打钻取芯 现场勘探 实验室力学及矿物组分测试
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Novel Air Purification System for Installation in Air Handling Units: Development, Assembly and Experimental Analysis
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作者 Rafael Simao Ferreira de Sousa 《Journal of Chemistry and Chemical Engineering》 2013年第9期885-891,共7页
Nowadays, people pass 90% of their time in closed spaces, therefore, an increasing care in the creation and upkeep of healthier environments as a personal and as professional level become a major issue. The present pr... Nowadays, people pass 90% of their time in closed spaces, therefore, an increasing care in the creation and upkeep of healthier environments as a personal and as professional level become a major issue. The present project has as goal the verification and optimization of the implicit need of an OCRAMclima~ AHU (air handling units) in IAQ (indoor air quality) and its effectiveness in treatment and/or air purification, having as basis the legal national and European requirements for IAQ. This work was based on the study of the state of the art of the techniques in air purification and in the evaluation of their performance, culminating in the production of the prototype OCRAMclima~ NPS (nano purifying system). The purifying phenomena involved are UVGI (ultraviolet germicidal irradiation) and catalytic ionization of air. The performance test was accomplished in a closed loop circuit, which results, obtained by an independent IAQ analyst, were satisfactory, indicating the viability of application of this system to indoor air disinfection. The outcome revealed that the conjugating of both phenomena, the air sterilizing by UV and catalytic ionization, is efficient when used for air purification, mainly for volatile organic compounds and bioaerosols. 展开更多
关键词 Indoor air quality ultraviolet germicidal irradiation catalytic ionization titanium dioxide air microbiologicalpurification volatile organic compounds oxidation.
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An Experimental Deprivation Study of Mobile Phones, Internet and TV
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作者 Elisabeth Platzer Otto Petrovic 《Computer Technology and Application》 2011年第8期600-606,共7页
This paper presents the results of an experimental deprivation study conducted with 64 participants. All participants had to do without mobile phone, internet and TV for 15 days each. The main research objective was t... This paper presents the results of an experimental deprivation study conducted with 64 participants. All participants had to do without mobile phone, internet and TV for 15 days each. The main research objective was to examine the differences of indispensability levels and experiences during these non-usage phases. Mobile phones turned out to be most indispensable followed by Internet. Involvement of the medium into daily routine is an important part of short-term indispensability and will be dealt with in detail in this paper. 展开更多
关键词 Media indispensability experimental deprivation study daily routine involvement.
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Triangular Halogen Bond and Hydrogen Bond Supramolecular Complex Consisting of Carbon Tetrabromide, Halide, and Solvent Molecule: A Theoretical and Spectroscopic Study
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作者 Yu-jie Wu Xiao-ran Zhao +1 位作者 Hai-yue Gao Wei-jun Jin 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第3期265-273,共9页
The theoretical calculation and spectroscopic experiments indicate a kind of triangular three bonding supramolecular complexes CBr4…X^-…-H-C, which consist of carbon tetrabromide, halide, and protic solvent molecule... The theoretical calculation and spectroscopic experiments indicate a kind of triangular three bonding supramolecular complexes CBr4…X^-…-H-C, which consist of carbon tetrabromide, halide, and protic solvent molecule (referring to dichloromethane, chloroform and acetonitrile), can be formed in solution. The strength of halogen and hydrogen bonds in the triangular complexes using halide as common acceptor obeys the order of iodide〉bromide〉chloride. The halogen and hydrogen bonds work weak-cooperatively. Charge transfer bands of halogen bonding complexes between CBra and halide are observed in UV-Vis absorption spectroscopy in three solvents, and then the stoichiometry of 1:1, formation constants K and molar extinction coefficients ε of the halogen bonding complexes are obtained by Benesi-Hildebrand method. The K and ε show a dependence on the solvent dielectric constant and, on the whole, obey an order of iodide〉bromide〉chloride in the same solvents. Furthermore, the C-H vibrational frequencies of solvent molecules vary obviously with the addition of halide, which indicates the C-H…X- interaction. The experimental data indicate that the halogen bond and hydrogen bond coexist by sharing a common halide acceptor as predicted by calculation. 展开更多
关键词 Halogen bond Hydrogen bond HALIDE Carbon tetrabromide Charge transfer
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Research to Improve the Effectiveness of the Government's Economic Management of Performance Management
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作者 Yige Wang 《International Journal of Technology Management》 2014年第5期55-57,共3页
Government Performance Management is a new government management pattern. It plays an important role in the development of the local government and an important part of the government human resource management. Since ... Government Performance Management is a new government management pattern. It plays an important role in the development of the local government and an important part of the government human resource management. Since China began to implement its government performance management, it has obtained some initial results. But it is still in the exploratory and improvement stage. Because a lot of problems arise in the actual operation process, so theoretical research and practice experience need to be further improved. Therefore, analyzing the local government perfornaance management problems and exploring strategies to improve the performance management are currently the objective requirements of the socialist market economy construction and governance reform in China and will have great significance. 展开更多
关键词 Kcywords: Government' s Economic Management PERFORMANCE MANAGEMENT
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Novel Algorithm for Active Noise Control Systems Based on Frequency Selective Filters
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作者 赵洪亮 《Journal of Measurement Science and Instrumentation》 CAS 2010年第2期196-200,共5页
A novel algorithm for active noise control systems based on frequency selective filters (FSFANC) is presented in the paper. The FSFANC aims at the multi-tonal noise attenuation problem. One FSFANC system copes with ... A novel algorithm for active noise control systems based on frequency selective filters (FSFANC) is presented in the paper. The FSFANC aims at the multi-tonal noise attenuation problem. One FSFANC system copes with one of the tonal components, and several FSFANC systems can run independently in paralld to cancel the selected multiple tones. The proposed algorithm adopts a simple structure with only two coefficients that can be explained as the real and imaginary parts of the structure to model the secondary path, and estimates the secondary path by injecting sinusoidal identification signals. Theoretical analysis and laboratory experiments show that the proposed algorithm possesses stone advantages, such as simpler structure, less computational burden, greater stability, and fast converging speed. 展开更多
关键词 active noise oontrol secondary path on4ine estimation
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Effects of experimental conditions on the molecular composition of maltenes and asphaltenes derived from oilsands bitumen: Characterized by negative-ion ESI FT-ICR MS 被引量:2
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作者 WANG LiTao HE Chen +5 位作者 LIU Yang ZHAO SuoQi ZHANG YaHe XU ChunMing CHUNG Keng H. SHI Quan 《Science China Chemistry》 SCIE EI CAS 2013年第7期863-873,共11页
A vacuum topped Canadian oilsands bitumen (VTB) was subjected to solvent precipitation and subsequently characterized by elemental analysis, gel permeation chromatograph (GPC), IH-NMR spectroscopy and negative-ion... A vacuum topped Canadian oilsands bitumen (VTB) was subjected to solvent precipitation and subsequently characterized by elemental analysis, gel permeation chromatograph (GPC), IH-NMR spectroscopy and negative-ion electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Effects of experimental conditions such as solvent types (n-Cs, n-C6, and n-C7), solvent purity, and solvent washing time on asphaltenes yields, bulk composition, and molecular composition of detectable heteroatom compounds in ESI source were determined. Elemental nitrogen and sulfur were enriched in asphaltenes while elemental oxygen had comparable content in maltenes and asphaltenes. Molecular compo- sition of asphaltenes varies with separation conditions. The N1 and O1 species identified by ESI FT-ICR MS were enriched in maltenes. The 02 species exhibited two different double bond equivalents (DBE) distributions and solubility in normal paraffin solvents, indicating two types of molecular structures. Multi oxygen atom containing compounds mainly detected in asphal- tenes. Compound class distributions are similar for maltenes derived from n-Cs, n-C6, and n-C7 , as well as for asphaltenes. The cyclic paraffin impurities in normal paraffin solvents had a significant influence on asphaltenes yields and heteroatom molecu- lar composition. A portion of neutral N1 species and acidic 02 species adsorbed on asphaltenes could be dissolved by increas- ing washing time. Cautions should be exercised when interpreting the properties and composition of asphaltenes obtained with different experimental conditions. 展开更多
关键词 asphaltene precipitation experimental conditions bulk properties molecular composition ESI FT-ICR MS
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Effects of Wenxiao Ⅱ Decoction on the expression of MCP-1 and VCAM-1 in atherosclerotic rabbits 被引量:2
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作者 霍清萍 刘含嫣 +1 位作者 梁芳 王宇新 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2012年第2期267-272,共6页
OBJECTIVE:To observe the effects of different doses of Wenxiao Ⅱ Decoction on the expression of monocyte chemoattractant protein-1(MCP-1) and vascular cell adhesion molecule-1(VCAM-1) in an experimental model of athe... OBJECTIVE:To observe the effects of different doses of Wenxiao Ⅱ Decoction on the expression of monocyte chemoattractant protein-1(MCP-1) and vascular cell adhesion molecule-1(VCAM-1) in an experimental model of atherosclerosis in rabbits and to explore the mechanism by which it alleviates atherosclerosis.METHODS:Sixty 3-4 month-old New Zealand rabbits of both sexes were randomly divided into six groups:simvastain;model;blank;and high-dose,mid-dose,and low-dose Wenxiao Ⅱ Decoction groups.Except for those in the blank group,all rabbits were fed a high-cholesterol diet.Carotid atherosclerosis was established by balloon-induced injury to the endothelium of the carotid artery in conjunction with consumption of a high-cholesterol diet.After 8 weeks,all rabbits were killed to evaluate the expression of MCP-1 and VCAM-1 by immunohistochemical staining.RESULTS:Expressions of MCP-1 and VCAM-1 were significantly decreased in all groups except the blank group compared with the model group(P<0.05).When compared with the simvastain group only variation of MCP-1 expression in low-dose group was not appreciable,and the differences were indistinct(P<0.05).When comparing among Wenxiao Ⅱ Decoction groups,MCP-1 expression in the mid-and high-dose groups was significantly lower than that seen in the low-dose group(P<0.01),but there were no differences among three dosage groups with respect to VCAM-1 expression(P>0.05).CONCLUSION:These data suggested that high,mid,and low doses of Wenxiao Ⅱ Decoction can inhibit the expression of MCP-1 and VCAM-1,which may prevent the formation of or stabilize atherosclerotic plaques.There may be a direct relationship between the dosage of Wenxiao Ⅱ Decoction and its therapeutic efficacy. 展开更多
关键词 Traditional Chinese Medicine Wenxiao II Decoction Atherosclerosis Inflammatory Monocyte chemoattractant protein-1 Vascular cell adhesion molecule-1
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