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A tailored database combining reference compound-derived metabolite,metabolism platform and chemical characteristic of Chinese herb followed by activity screening:Application to Magnoliae Officinalis Cortex
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作者 Zhenzhen Xue Yudong Shang +2 位作者 Lan Yang Tao Li Bin Yang 《Journal of Pharmaceutical Analysis》 2025年第4期775-785,共11页
A strategy combining a tailored database and high-throughput activity screening that discover bioactive metabolites derived from Magnoliae Officinalis Cortex(MOC)was developed and implemented to rapidly profile and di... A strategy combining a tailored database and high-throughput activity screening that discover bioactive metabolites derived from Magnoliae Officinalis Cortex(MOC)was developed and implemented to rapidly profile and discover bioactive metabolites in vivo derived from traditional Chinese medicine(TCM).The strategy possessed four characteristics:1)The tailored database consisted of metabolites derived from big data-originated reference compound,metabolites predicted in silico,and MOC chemical profile-based pseudomolecular ions.2)When profiling MOC-derived metabolites in vivo,attentions were paid not only to prototypes of MOC compounds and metabolites directly derived from MOC compounds,as reported by most papers,but also to isomerized metabolites and the degradation products of MOC compounds as well as their derived metabolites.3)Metabolite traceability was performed,especially to distinguish isomeric prototypes-derived metabolites,prototypes of MOC compounds as well as phase I metabolites derived from other MOC compounds.4)Molecular docking was utilized for high-throughput activity screening and molecular dynamic simulation as well as zebrafish model were used for verification.Using this strategy,134 metabolites were swiftly characterized after the oral administration of MOC to rats,and several metabolites were reported for the first time.Furthermore,17 potential active metabolites were discovered by targeting the motilin,dopamine D2,and the serotonin type 4(5-HT4)receptors,and part bioactivities were verified using molecular dynamic simulation and a zebrafish constipation model.This study extends the application of mass spectrometry(MS)to rapidly profile TCM-derived metabolites in vivo,which will help pharmacologists rapidly discover potent metabolites from a complex matrix. 展开更多
关键词 Tailored database Metabolite traceability activity screening Magnoliae Officinalis Cortex In vivo metabolite
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An Introduction to the Latest-generation Spatial Database of Active Tectonics of China
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作者 Qu Chunyan Deng Qidong 《Earthquake Research in China》 2009年第2期237-243,共7页
Based on ArcGIS and MapInfo software, we digitized the active tectonics map (1:4,000,000) of China, which was compiled and revised by academician Deng Qidong, and built the spatial database of active tectonics of Chin... Based on ArcGIS and MapInfo software, we digitized the active tectonics map (1:4,000,000) of China, which was compiled and revised by academician Deng Qidong, and built the spatial database of active tectonics of China. The database integrates rich active tectonic data, such as a catalogue of earthquakes with magnitude above 6.0, active faults, Quaternary basins, active folds and their associated attribute parameters, and implements scientific and effective management to this data. At the same time, the spatial database joins the spatial map data and the associated attribute data together, which implements the data query between spatial properties and attribute parameters and also makes it possible to perform spatial analysis with different data layers. These provide much convenience for earthquake study and allows engineering construction institutions to use this data in practical applications. 展开更多
关键词 active tectonics Spatial database GIS
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Incorporating Fuzzy Inference in Active Database Rules
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作者 郭海英 台立钢 钟廷修 《Journal of Donghua University(English Edition)》 EI CAS 2003年第3期113-116,共4页
Active databases react to stimulation, or event from inside or outside the system without user or application interference through Events Conditions Actions(ECA) rules (triggers). ECA rule is defined as: ON event IF c... Active databases react to stimulation, or event from inside or outside the system without user or application interference through Events Conditions Actions(ECA) rules (triggers). ECA rule is defined as: ON event IF condition THEN action, which means when an event happens, if the condition is satisfied then the corresponding action is executed. The nature of ECA rule makes it an appropriate means to model dynamic character of systems, as gained much studies during recent years. Traditional ECA rule is crisp, which means their events, condition (s) and action(s) are accurate. As indicate that ECA rules can only represent precise knowledge. But knowledge is usually fuzzy in engineering. A concept of fuzzy ECA rules characterized with fuzzy event, fuzzy condition and fuzzy action is proposed in this article.The realization avenues of fuzzy triggers are discussed. The work we have done blazes a way in representing approximate syntax in active database application systems. At last a case of 'overheating alarm' is given to illustrate the approach. 展开更多
关键词 ECA rule active database fuzzy inference fuzzy trigger
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米非司酮对小鼠着床期子宫内膜活化的β-连环蛋白(active β-catenin)表达的影响 被引量:1
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作者 陈世知 何俊琳 +4 位作者 刘学庆 丁裕斌 黄静 陈雪梅 王应雄 《生殖与避孕》 CAS CSCD 北大核心 2009年第8期489-493,507,共6页
目的:探讨活化的β-连环蛋白(active β-catenin)在胚胎着床过程中的作用。方法:将孕第2日(d2)昆明小鼠随机分成3组,每组30只,A组:孕d2单次背部皮下注射0.1ml米非司酮(1.2mg/ml);B组(溶剂对照):以等量1,3-丙二醇代替米非司酮;C组:不作... 目的:探讨活化的β-连环蛋白(active β-catenin)在胚胎着床过程中的作用。方法:将孕第2日(d2)昆明小鼠随机分成3组,每组30只,A组:孕d2单次背部皮下注射0.1ml米非司酮(1.2mg/ml);B组(溶剂对照):以等量1,3-丙二醇代替米非司酮;C组:不作任何处理。用免疫组织化学、间接免疫荧光、Western blotting方法定性、定量、定位检测3组小鼠在妊娠d3 ̄7活化的β-连环蛋白的动态表达。结果:B、C组小鼠子宫内膜中活化的β-连环蛋白于孕d3在腺上皮和腔上皮、基质细胞质和细胞膜表达;妊娠d4在腔上皮细胞质和细胞膜强表达,并达高峰;妊娠d5 ̄7在腺上皮、血管内皮、腔上皮下基质细胞膜和细胞质表达,且B、C组间在妊娠d3 ̄7各时间点的表达无显著性差异(P>0.05);A组小鼠妊娠d3 ̄7活化的β-连环蛋白的表达较B、C组显著降低(P<0.01),在妊娠d4表达量未见高峰,且表达部位局限于基质细胞,腔上皮无表达。结论:米非司酮可能通过抑制孕激素与其受体结合而下调活化的β-连环蛋白表达,进而抑制子宫内膜黏附性,影响子宫内膜容受性的建立而阻碍胚胎顺利着床。 展开更多
关键词 米非司酮 活化的β-连环蛋白(active β-catenin) 子宫内膜 胚胎着床 小鼠
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Efficient electroreduction of nitrate via enriched active phases on copper-cobalt oxides 被引量:1
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作者 Ling Fang Sha Wang +4 位作者 Shun Lu Fengjun Yin Yujie Dai Lin Chang Hong Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第4期204-209,共6页
Electrochemical conversion of nitrate(NO_(3)~-) to ammonia(NH_(3)) can target two birds with one stone well, in NO_(3)^(-)-containing sewage remediation and sustainable NH_(3) production. However, single metalbased ca... Electrochemical conversion of nitrate(NO_(3)~-) to ammonia(NH_(3)) can target two birds with one stone well, in NO_(3)^(-)-containing sewage remediation and sustainable NH_(3) production. However, single metalbased catalysts are difficult to drive high-efficient NO_(3)~- removal due to the multi-electron transfer steps.Herein, we present a tandem catalyst with simple structure, Cu-Co binary metal oxides(Cu-Co-O), by engineering intermediate phases as catalytic active species for NO_(3)~- conversion. Electrochemical evaluation,X-ray photoelectron spectroscopy, and in situ Raman spectra together suggest that the newly-generated Cu-based phases was prone to NO_(3)~- to NO_(2)~- conversion, then NO_(2)~- was reduced to NH_(3) on Co-based species. At an applied potential of -1.1 V vs. saturated calomel electrode, the Cu-Co-O catalyst achieved NO_(3)~- -N removal of 90% and NH_(3) faradaic efficiency of 81% for 120 min in 100 m L of 50 mg/L NO_(3)~- -N,consuming only 0.69 k Wh/mol in a two-electrode system. This study provides a facile and efficient engineering strategy for developing high-performance catalysts for electrocatalytic nitrate conversion. 展开更多
关键词 NO_(3)^(-)-containing sewage remediation Electrocatalytic reduction Copper-cobalt oxides Tandem reactivity Enriched active phases
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Do Radio-loud Active Galactic Nuclei really follow the same M_(BH)-σ_* Relation as Normal Galaxies?
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作者 Yi Liu Dong-Rong Jiang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第6期655-662,共8页
In an examination of the relationship between the black hole mass MBH and stellar velocity dispersion σ* in radio-loud active galactic nuclei (AGNs), we studied two effects which may cause uncertainties in the bla... In an examination of the relationship between the black hole mass MBH and stellar velocity dispersion σ* in radio-loud active galactic nuclei (AGNs), we studied two effects which may cause uncertainties in the black hole mass estimates of radio-loud AGNs: the relativistic beaming effect on the observed optical continuum radiation and the orientation effect on the broad emission line width. After correcting these two effects, we re-examined the MBH- σ[OIII] relation for a sample of radio-loud and radio-quiet AGNs, and found the relation for radio-loud AGNs still deviated from that for nearby normal galaxies and radio-quiet AGNs. We also found there is no significant correlation between radio jet power and narrow [OIII] line width, indicating absence of strong interaction between radio jet and narrow line region. It may be that the deviation of the MBH-σ* relation of radio-loud AGNs is intrinsic, or that the [OIII] line width is not a good indicator of σ* for radio-loud AGNs. 展开更多
关键词 black hole physics - galaxies active - galaxies nuclei - quasars general
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Disk-Corona Model in Active Galactic Nuclei: an Observational Test
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作者 Fang Yang Chen Hu +1 位作者 Yan-Mei Chen Jian-Min Wang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第3期353-363,共11页
We compiled a sample of 98 radio-quiet active galactic nuclei observed by ASCA, Chandra, XMM-Newton, INTEGRAL and Swift with the aim of testing the formation of hot corona and the magnetic shear stress operating in a ... We compiled a sample of 98 radio-quiet active galactic nuclei observed by ASCA, Chandra, XMM-Newton, INTEGRAL and Swift with the aim of testing the formation of hot corona and the magnetic shear stress operating in a disk-corona system. We found a strong correlation between the hard X-ray luminosity, bolometric luminosity LBol and Eddington luminosity LEdd, in the sense that the fraction f of hard X-ray to the bolometric luminosity is inversely proportional to the Eddington ratio. This correlation favors the shear stress tensor being of the form of trФ∝ Pgas, with which the disk-corona structure is stable. 展开更多
关键词 accretion accretion disks - galaxies active - magnetic fields
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Exosomal miR-137-3p targets UBE3C to activate STAT3,promoting migration and differentiation into endometrial epithelial cell of human umbilical cord mesenchymal stem cells under hypoxia
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作者 Wan-Yu Zhang Si-Miao Liu +1 位作者 Han-Bi Wang Cheng-Yan Deng 《World Journal of Stem Cells》 2025年第4期48-63,共16页
BACKGROUND Thin endometrium,leading cause of recurrent implantation failure and infertility,has been found to respond to exosomes.AIM To investigate the efficacy of exosomes in addressing the issue of thin endometrium... BACKGROUND Thin endometrium,leading cause of recurrent implantation failure and infertility,has been found to respond to exosomes.AIM To investigate the efficacy of exosomes in addressing the issue of thin endometrium.METHODS RNA sequencing and reverse transcription-quantitative polymerase chain reaction were employed to identify differentially expressed microRNAs(miRNAs)in human umbilical cord mesenchymal stem cell(hucMSC)treated with exosomes enriched with endometrial cell-derived components.Additionally,Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were conducted to highlight significant enrichment in specific biological pathways,molecular functions,and cellular components.Transwell and wound healing assays were performed to assess migratory potential,and western blotting was detected protein level.RESULTS A total of 53 differentially expressed miRNAs were identified in hucMSC treated with exosomes enriched with endometrial cell-derived components,comprising 27 upregulated and 26 downregulated miRNAs,which includes miR-137-3p.Enhanced migratory potential was observed in the Transwell and wound healing assays,and western blotting confirmed the epithelial differentiation of hucMSC and the increased p-signal transducer and activator of transcription 3.These effects were attributed to the upregulation of miR-137-3p.CONCLUSION miR-137-3p in exosomes from hypoxia-affected endometrial epithelial cell stimulates the signal transducer and activator of transcription 3 signaling pathway,enhancing the migration and differentiation of hucMSC into endometrial epithelial cell. 展开更多
关键词 Endometrial epithelial cells EXOSOMES miR-137-3p Ubiquitin protein ligase E3C Signal transducer and activator of transcription 3 Human umbilical cord mesenchymal stem cells
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A NEW OPTICALLY ACTIVE POLYURETHANE DERIVED FROM CHIRAL(2R,3R)(+)-DIETHYL L-TARTRATE AND DIISOCYANATE
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作者 陈传福 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第4期371-373,共3页
Optically active polyurethane was synthesized by the polyaddition of (2R, 3R)-(+)-diethyl L-tartrate (DET), 4,4'-diphenylmethane diisocyanate (MDI) and polyethylene glycol (PEG) with various molecular weights at 6... Optically active polyurethane was synthesized by the polyaddition of (2R, 3R)-(+)-diethyl L-tartrate (DET), 4,4'-diphenylmethane diisocyanate (MDI) and polyethylene glycol (PEG) with various molecular weights at 60 degrees C in DMSO. The polymers were characterized by specific rotation, DSC and H-1 NMR spectra. 展开更多
关键词 (2R 3R)-(+)-diethyl L-tartrate optically active polyurethane
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Model Reduction Methods for High-Rise Buildings with Active Mass Damper Control Systems
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作者 Jun Teng Hou-Bing Xing Cheng-Yin Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第6期37-45,共9页
To improve the performance of an active mass damper control system,the controller should be designed based on a reduced-order model. An improved method based on balanced truncation method was proposed to reduce the di... To improve the performance of an active mass damper control system,the controller should be designed based on a reduced-order model. An improved method based on balanced truncation method was proposed to reduce the dimension of high-rise buildings,and was compared with other widely used reduction methods by using a framework with ten floors. This optimized method has improvement of reduction process and choice of the order. Based on the reduced-order model obtained by the improved method and pole-assignment algorithm,a controller was designed. Finally,a comparative analysis of structural responses,transfer functions,and poles was conducted on an actual high-rise building. The results show the effectiveness of the improved method. 展开更多
关键词 high-rise building active mass damper model reduction controller designCLC number:TU352 Document code:AArticle ID:1005-9113(2013)06-0037-09
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Expression, Purification and Insecticidal Activity Analysis of Cry1Ac without Helix α-1
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作者 刘京国 郭蓓 +1 位作者 赵晓萌 师光禄 《Agricultural Science & Technology》 CAS 2012年第2期265-267,303,共4页
[Objective] This study aimed to analyze the expression, purification and insecticidal activity of Cry1Ac without helix α-1 of domain I in E. coli. [Method] Plasmid of B. thuringiensis HD-1 was used as the template fo... [Objective] This study aimed to analyze the expression, purification and insecticidal activity of Cry1Ac without helix α-1 of domain I in E. coli. [Method] Plasmid of B. thuringiensis HD-1 was used as the template for amplification of Cry1Ac gene, which was linked with pET28a vector to construct the recombinant plasmid. After transformation and IPTG induction, expression of target protein was detected by using SDS-PAGE method. Target protein was extracted and coated on the surface of feed for H. armigera to determine the insecticidal activity. [Result] Cry1Acdela1 gene could normally express the target protein in E. coli. However, the target protein existed in the form of inclusion body. Results of bioassay analysis showed that under the same concentration, fatality rate of activated Cry1Ac toxin reached above 75%, while that of Cry1Acdelα1 was only about 10%. [Conclusion] E. coli-expressed Cry1Acdelα1 had no insecticidal activity against H. armigera. 展开更多
关键词 CRY1AC α-1 fragment Insecticidal activity
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基于ActiveX技术的教务/学生管理Web数据库应用系统的分析与设计 被引量:1
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作者 李丽 鱼滨 霍洪田 《德州学院学报》 2003年第2期71-75,共5页
分析了B/S模式的Web数据库应用系统中的ActiveX技术的应用 ,并根据ActiveX技术的运行环境和特点利用构件化程序设计方法分析和设计了教务
关键词 教务/学生管理系统 activeX技术 B/S模式 WEB数据库应用系统 构件化程序设计
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使用Oracle Active Data Guard实现PMS2.0数据库读写分离初探 被引量:1
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作者 吴尚 王萍 +3 位作者 胡聪 张永梅 张靖 郑重珩 《无线互联科技》 2018年第9期43-44,53,共3页
文章研究了使用Oracle Active Data Guard实现PMS2.0数据库读写分离。生产管理系统PMS是电力信息系统中重要的核心业务系统,随着数据量不断快速增长,数据库的I/O吞吐量以及资源的耗用愈发凸显性能瓶颈,造成业务用户并发操作延时甚至失... 文章研究了使用Oracle Active Data Guard实现PMS2.0数据库读写分离。生产管理系统PMS是电力信息系统中重要的核心业务系统,随着数据量不断快速增长,数据库的I/O吞吐量以及资源的耗用愈发凸显性能瓶颈,造成业务用户并发操作延时甚至失败。传统的单节点数据库或ORACLE RAC集群已无法应对。根据目前成熟的业界解决方案,采用读写分离的方式,可以有效解决这个问题。 展开更多
关键词 ORACLE数据库 PMS2.0业务 读写分离 活动数据卫士 性能优化
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VB调用ActiveX进行VFP数据库开发
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作者 阎红灿 付景红 刘凤春 《河北理工学院学报》 2004年第2期56-58,67,共4页
介绍了VB6.0中常用的三种数据库访问技术,通过分析ADO技术的工作原理,给出了利用VB6.0的 ActiveX数据库控件进行 VFP数据库应用开发的主要技术和实现方法。
关键词 VB activeX VFP数据库 数据库控件 ODBC数据源 数据库访问
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In Vitro Anti-influenza Virus Activities of Sulfated Polysaccharide Fractions from Gracilaria lemaneiformis 被引量:22
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作者 Mei-zhen CHEN Hao-gui XIE La-wei YANG Zao-hui LIAO Jie YU 《Virologica Sinica》 SCIE CAS CSCD 2010年第5期341-351,共11页
In this paper, in vitro anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiforrnis were investigated. Cytotoxicities and antiviral activities of Gracilaria lemaneiformis polysa... In this paper, in vitro anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiforrnis were investigated. Cytotoxicities and antiviral activities of Gracilaria lemaneiformis polysaccharides (PGL), Gracilaria lemaneiformis polysaccharide fraction-1 (GL-1), Gracilaria lemaneiformis polysaccharide fraction-2 (GL-2) and Gracilaria lemaneiformis polysaccharide fraction-3 (GL-3) were studied by the Methyl thiazolyl tetrazolium (MTT) method, and the inhibitory effect against Human influenza virus H1-364 induced cytopathic effect (CPE) on MDCK cells were observed by the CPE method. In addition, the antiviral mechanism of PGL was explored by Plaque forming unit (PFU), MTT and CPE methods. The results showed: i) Cytotoxicities were not significantly revealed, and H1-364 induced CPE was also reduced treated with sulfated polysaccharide fractions from Gracilaria lemaneiformis; ii) Antiviral activities were associated with the mass percentage content of sulfate groups in polysaccharide fractions, which was about 13%, in polysaccharides (PGL and GL-2) both of which exhibited higher antiviral activity; iii) A potential antiviral mechanism to explain these observations is that viral adsorption and replication on host cells were inhibited by sulfated polysaccharides from Gracilaria lemaneiformis. In conclusion, Anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiformis were revealed, and the antiviral activities were associated with content of sulfate groups in polysaccharide fractions 展开更多
关键词 Gracilaria lemaneiformis Sulfated polysaccharide Antiviral activity Human influenza virusH1-364
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Anthraquinone derivatives produced by marine-derived Penicillium flavidorsum SHK1-27and their antitumor activities 被引量:16
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作者 REN Hong GU Qian-qun CUI Cheng-bin 《中国药物化学杂志》 CAS CSCD 2007年第3期148-154,共7页
Aim To investigate the antitumor agents produced by marine-derived Penicillium flavidorsum SHK1-27.Methods The producing strain SHK1-27was fermented in a rotary shaker and bioactive metabolites in the fermentation bro... Aim To investigate the antitumor agents produced by marine-derived Penicillium flavidorsum SHK1-27.Methods The producing strain SHK1-27was fermented in a rotary shaker and bioactive metabolites in the fermentation broth were isolated through a bioassay-guided sepa-ration procedure.Structures of the bioactive compounds were investigated by spectroscopic meth-ods and their in vitro antitumor activities were assayed by the SRBmethod using K562 cells.Re-sults Eight anthraquinone derivatives were isolated from the fermentation broth of P.flavidor-sum SHK1-27 and were identified as nidurufin(1),averufin(2),8-O-methylaverufin(3),6,8-O-dimethylaverufin(4),versicolorin B(5),versicolorin A(6),versiconol(7)and averantin(8),re-spectively.Compounds 1-8 inhibited the proliferation of K562 cells and could be classified as strong(1 and 8 with the IC5o values of 12.6 and 27.7μmol·L"'respectively),moderate(2,5,6 and 7 with the ICso values of 72.4,91.0,98.7 and 93.4μmol·L-'respectively)and weak(3and 4 both with the same ICso value of>100μmol·L-')activity groups,respectively.The results showed some structure-activity relationships.Conclusion This is the first report of compounds 1-8 as the secondary metabolites of P.flavidorsum species,1,5 and 6 were isolated from fungal metabolites of the genus Penicillium for the first time,and 7 was found to occur in nature for the first time.The antitumor activities of compounds 1-8 on K562 cells were also reported for the first time in the present study. 展开更多
关键词 ANTHRAQUINONE structuralidentification antitumor activity K562 marine-derived Penicillium flavidorsum SHK1-27
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Activity of the Fungicide JS399-19 Against Fusarium Head Blight of Wheat and the Risk of Resistance 被引量:8
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作者 CHEN Yu WANG Wen-xiang +3 位作者 ZHANG Ai-fang GU Chun-yan ZHOU Ming-guo GAO Tong-chun 《Agricultural Sciences in China》 CAS CSCD 2011年第12期1906-1913,共8页
This report reviews the characteristics of JS399-19, a novel cyanoacrylate fungicide. JS399-19 strongly inhibits the mycelial growth of the fungal plant pathogens of the genus Fusarium and exhibits great potential in ... This report reviews the characteristics of JS399-19, a novel cyanoacrylate fungicide. JS399-19 strongly inhibits the mycelial growth of the fungal plant pathogens of the genus Fusarium and exhibits great potential in controlling Fusarium head blight (FHB) on wheat and other cereals. The mode of action of JS399-19 is evidently different from that of benzimidazole (for example, carbendazim) and other sort of fungicides, making it a possible replacement for carbendazim in China to manage carbendazim-resistant subpopulations of Fusarium graminearum and F. asiaticum. JS399-t9 has excellent protective and curative activity against these pathogens. Incorrect use of this fungicide, however, is likely to select for resistance. Among JS399-19-resistant mutants of F. asiaticum induced in the laboratory, the resistant level of mutants was high and the phenotype of resistance against JS399-19 was conferred by a major gene by genetic analysis. The fitness of laboratory-induced JS399-19-resistant mutants of F. asiaticum was nearly equal to that of their parents. JS399-19 lacks cross resistance with other sort fungicides. To control FHB with JS399-19 and to delay the development of the fungicide-resistance, farmers should use tank mixtures containing JS399-19 and carbendazim, metconazole, tebuconazole, or prothioconazole. 展开更多
关键词 fungicide JS399-19 cyanoacrylate fungicide Fusarium head blight activITY resistance risk
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Synthesis,biological activities and 3D-QSAR studies of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety 被引量:5
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作者 Jingbo Liu Fengyun Li +5 位作者 Yuanhong Wang Haoxuan Zhang Jingyue Dong Pengwei Sun Yuxin Li Zhengming Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第3期668-671,共4页
A series of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety were synthesized and characterized on the basis of NMR and elemental analysis(EA). The crystal structure of(R)-N-(... A series of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety were synthesized and characterized on the basis of NMR and elemental analysis(EA). The crystal structure of(R)-N-(2-methyl-1-(methylthio)propan-2-yl)-2-(4-nitrophenyl)-4,5-dihydrothiazole-4-carboxamide(13 d) was determined to show R configuration. The bioasssy results indicated that most title compounds displayed good and broad spectrum antifungal activities against several phytopathogenic fungi. The structure activity relationships were discussed. Based on the antifungal activity of title compounds against Phytophthora capsici, a CoMSIA calculation was performed to establish a 3 D-QSAR model, which revealed that electrostatic and hydrophobic fields were the two most significant factors for antifungal activity. According to the established 3D-QSAR model, structure optimization was carried out to find(R)-N-((R)-1-(methylthio)propan-2-yl)-2-(p-tolyl)-4,5-dihydrothiazole-4-carboxamide(15 h)with excellent activity against Phytophthora capsici, thus emerging as a new lead compound for novel antiphytopathogenic fungus agent development. 展开更多
关键词 (R)-2-Phenyl-4 5-dihydrothiazole-4- CARBOXAMIDE SULFUR ETHER Antifungal activity SARs COMSIA model
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Statistics of Superluminal Motion in Active Galactic Nuclei 被引量:3
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作者 Yong-Wei Zhang Jun-Hui Fan 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第4期385-394,共10页
We have collected an up-to-date sample of 123 superluminal sources (84 quasars, 27 BL Lac objects and 12 galaxies) and calculated the apparent velocities (βapp) for 224 components in the sources with the A-CDM mo... We have collected an up-to-date sample of 123 superluminal sources (84 quasars, 27 BL Lac objects and 12 galaxies) and calculated the apparent velocities (βapp) for 224 components in the sources with the A-CDM model. We checked the relationships between their proper motions, redshifts,βapp and 5 GHz flux densities. Our analysis shows that the radio emission is strongly boosted by the Doppler effect. The superluminal motion and the relativistic beaming boosting effect are, to some extent, the same in active galactic nuclei. 展开更多
关键词 GALAXIES jets - galaxies general - BL Lacertae objects active - quasars data analysis
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Calculation of Activity Coefficients for Components in Ti-15-3 Melt 被引量:3
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作者 苏彦庆 刘源 +2 位作者 郭景杰 贾均 丁宏升 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第1期54-57,共4页
Based on Kohler’s ternary solution model and Miedemaa’s model for calculating the heats of formation-△Hij of binary Systems, the integral equation has ben established for calculating the activity coefficients in te... Based on Kohler’s ternary solution model and Miedemaa’s model for calculating the heats of formation-△Hij of binary Systems, the integral equation has ben established for calculating the activity coefficients in ternarysolution. With the equation, the activity coefficients in Ti-15-3 melt have been calculated. The results show that allof components’ activity coefficients are less than 1, in other wolds, compared with ideal solution, all components takeon a negative deviation. At 2000K, the activity coefficients in Ti-15-3 melt are shown as: about 0.9 for Ti, about0.85 for V, about 0. 1 for Al, aboaut 0.5 for Cr and about 0.23 for Sn. me addition of V lowers the activity coefficient of Ti, but raise the ones of Al, Cr and Sn. These results can be directly used to calculate the evaporation loss ofAl, Cr and Sn during the ISM(Induction Skull Melting) process and at the same time estimate the reactivity betweenTi-15-3 melt and refractory during the cast production. 展开更多
关键词 activITY COEFFICIENT Ti-15-3 alloy ISM process
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