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简介：ＣｏｍｐａｒｉｓｉｏｎｏｆＦＡＢａｎｄＭＡＬＤＩＭａｓｓＳｐｅｃｔｒｏｍｅｔｒｙｏｆＧｉｎｓｅｎｏｓｉｄｅｓ￥ＺｈｏｕＹｕ；ＬｉｕＺｈｉｑｉａｎｇ；ＳｏｎｇＦｅｎｇｒｕｉ；ＬｉｕＳｈｕｙｉｎｇ；ＬｉＸｉａｎｇｇａｏ；ＹｉｎＪｉａｎｇｙｕａｎ（１Ｃｈａ...

简介：Thenegativeionfastatombombardment(NIFAB)massspectraofmono-,di-saccharidesandglycosidesusingphenylboronicacid(PBA)asreagenthavebeenstudied.Intheionsource,PBAreactsstereospecificallywiththemoleculescontainingcis-vicinalglycolstoformcharacteristicions,fromwhichthestereo-isomersofsaccharidescanbedefinitelydistinguished.Disaccharidesandglyco-sideswithβ-glycosidiclinkageseemtobeunfavorabaletoreactwithPBA,therefore,bycomparisonoftheabundancesofthecharacteristicions,theconfigurationoftheglycosidiclinkageinthesecompoundsmaybeinferred.

简介：Thetime-of-flightmassspectrum(TOFMS)relativetotheresonanttwo-photonionizationofgasphasep-dichlorobenzenewasobtainedinthewavelengthrangeof240-250nmbyahome-madesystem.Aspecialdesignwasmadetoreducetheeffectofmemoryontheinnerwallofthesampleinletsystemsuitablefortheinvestigationofsemi-volatileorganiccompound.Inthiswavelengthrange,p-dichlorobenzenemoleculesfirstlyabsorbedonephotontobeexcitedfromthegToundstate~1A_g(S_0)tothefirstexcitedstate1B2u($1),thenabsorbedanotherphotontobeionized.Therelationshipbetweenthesignalintensityofp-dichlorobenzenemolecularionC_6H_4~(35)Cl_2~+at248-nmwavelengthandthelaserpowerwasgiven.The1.52powerindexofC_6H_4~(35)Cl_2~+wasatypicalidentificationofthe3/2powerlaw.TherelationshipbetweentheionsignalintensityofC_6H_4~(35)Cl_2~+andthesampleconcentrationwasclosetoalinearoneintheppm(V/V)range,whichledtoadetectionlimitof125ppb(V/V)forp-dichlorobenzene.

简介：AbstractBackground:Gliomas are the most common primary malignant brain tumors and have a poor prognosis. Early detection of gliomas is crucial to improve patient outcomes. Urine accumulates systematic body changes and thus serves as an excellent early biomarker source.Methods:At the biomarker discovery phase, we performed a self-controlled proteomics analysis by comparing urine samples collected from five glioma patients at the time of tumor diagnosis and after surgical removal of the tumor. At the biomarker validation phase, we further validated some promising proteins using parallel reaction monitoring (PRM)-based targeted proteomics in another cohort, including glioma, meningioma, and moyamoya disease patients as well as healthy controls.Results:Using label-free proteome quantitation (LFQ), we identified twenty-seven urinary proteins that were significantly changed after tumor resection, many of which have been previously associated with gliomas. The functions of these proteins were significantly enriched in the autophagy and angiogenesis, which are associated with glioma development. After targeted proteomics validation, we identified a biomarker panel (AACT, TSP4, MDHM, CALR, LEG1, and AHSG) with an area under the curve (AUC) value of 0.958 for the detection of gliomas. Interestingly, AACT, LEG1, and AHSG are also potential cerebrospinal fluid or blood biomarkers of gliomas.Conclusions:Using LFQ and PRM proteome quantification, we identified candidate urinary protein biomarkers with the potential to detect gliomas. This study will also provide clues for future biomarker studies involving brain diseases.

简介：Itwasfoundthatphosphorylationofsmallpeptidecouldimprovethesensitivityinmassspectrometry.DensityfunctionaltheorycalculationsshowedthattheenergyfortheprotonationofN-(O,O′-dimethyl)phosphorylglycylglycineislowerthanthatofglycylglycine.Thesecouldhelptounderstandingtheexperimentalresults.

简介：Chloramphenicolisanantibioticandoneofthepotentialcontaminantsinhoney.Solid-phaseextractionisthekeypretreatmentprocedureforanalysisofchloramphenicolinhoney.Inthiswork,anon-linepretreatmentliquidchromatography-tandemmassspectrometersystemforsensitive,reliableandhigherthroughputanalysiswasdeveloped.Withthemethylcellulose-immobilizedreversed-phasecolumn,sugarsinahoneysamplewereefficientlyremovedin1min.Asaresult,thelimitofquantitationofchloramphenicolwas20pg/mL(0.2μg/kghoney).

简介：为uveal黑瘤发现新biomarkers(嗯)由在病人分析浆液peptidomeprofile.METHODSProteomic系列与嗯在操作被分析前后并且与那些相比健康控制。磁性的亲密关系祷告被用来捕获浆液肽和帮助矩阵的激光解吸附作用/电离time-of-flight(MALDI-TOF)质量分光计被用来编49肽的浆液肽profiles.RESULTSA面板差别被表示在之间嗯病人和控制，哪个33肽具有在耐心的组的更高的紧张，16肽具有在控制的更高的紧张组。基于这些潜在的标记的联合使用，有1467和9289.0Da的吝啬的分子的群众的肽提供高敏感(83.3%)，特性(100%)和精确性率(93.0%)一起把黑瘤病人区分开来与健康控制。手术后地6mo指向时间，在外科前表示的许多肽差别的层次显示出病人和控制组之间的没有更多的统计差别。纤维蛋白原链先锋作为潜力被识别嗯markers.CONCLUSIONWe证明了一种方便、快的proteomic技术，亲密关系祷告分离和MALDI-TOF分析与生物信息的软件结合了，便于新奇biomarkers的鉴定为嗯。

简介：Isochronousmassspectrometry(IMS)instorageringsisapowerfultoolformassmeasurementsofexoticnuclewithveryshorthalf-livesdowntoseveraltensofmicroseconds,usingamulticomponentsecondarybeamseparatedin-ightwithoutcooling.However,theinevitablemomentumspreadofsecondaryionslimitstheprecisionofnuclearmassesdeterminedbyusingIMS.

简介：Xingxiong注射(XXI)是叶片白果树摘录和ligustrazine为心血管、脑血管的疾病的治疗作好准备的一个广泛地使用的中国草药的公式。与药理学研究相比，这个公式上的化学分析和质量控制研究是相对有限的。在现在的学习，高效液体层析结合了四极time-of-flight团spectrometry(HPLC-QTOFMS)方法在XXI被用于成分的全面分析。根据破碎规则和以前的报告，三十白果树flavonoids，四白果树萜烯内酯，和一碱被识别。高效液体层析结合了三倍的四极团spectrometry(HPLC-QQQMS)方法然后被使用确定在XXI的十主要成分。方法确认结果显示发达方法有理想的特性，线性，精确和精确性。白果树flavonoids的全部的内容关于22.05-25.51g·mL−1，白果树萜烯内酯数量分别地关于在XXI样品的六批的4.41-8.70g·mL−1。而且，余弦比率算法和距离大小被采用评估XXI样品的类似，并且结果表明了高质量的一致性。这个工作能在Xingxiong注射的质量控制上提供全面信息，它在一个合理质量控制标准的建立是有用的。

简介：Nuclearmassmeasurementsprovidevaluableinformationonthenuclearbindingenergywhichreflectsthesummedresultofallinteractionsamongitsconstituentprotonsandneutrons.Thesystematicandaccurateknowledgeofnuclearmasseshavewideapplicationinmanyareasofsubatomicphysicsrangingfromnuclearstructureandastrophysicstothefundamentalinteractionsandsymmetriesdependingontheachievedmassprecision[1].

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简介：Inthisstudywesystematicallyanalyzedtheelutionconditionoftrypticpeptidesandthecharacteristicsofidentifiedpeptidesinreversephaseliquidchromatographyandelectrospraytandemmassspectrometry(RPLC-MS/MS)analysis.Followingproteindigestionwithtrypsin,thepeptidemixturewasanalyzedbyon-lineRPLC-MS/MS.Bovineserumalbumin(BSA)wasusedtooptimizeacetonitrile(ACN)elutiongradientfortrypticpeptides,andCytochromeCwasusedtoretestthegradientandthesensitivityofLC-MS/MS.Thecharacteristicsofidentifiedpeptideswerealsoanalyzed.Inourexperiments,thesuitableACNgradientis5%to30%fortrypticpeptideelutionandthesensitivityofLC-MS/MSis50fmol.Analysisofthetrypticpeptidesdemonstratedthatlonger(morethan10aminoacids)andmulti-chargestate(+2,+3)peptidesarelikelytobeidentified,andthehydropathicityofthepeptidesmightnotberelatedtowhetheritismorelikelytobeidentifiedornot.Thenumberofidentifiedpeptidesforaproteinmightbeusedtoestimateitsloadingamountunderthesamesamplebackground.Moreover,inthisstudytheidentifiedpeptidespresentthreetypesofredundancy,namelyidentification,charge,andsequenceredundancy,whichmayrepresslowabundanceproteinidentification.

简介：Massspectroscopiccharacteristicsofphosphorylaminoacidswerestudiedindetailbypositiveandnegativeelectrosprayionizationmassspectrometry(ESI-MS)inconjunctionwithtandemmassspectrometry(MS/MS).BesidesN-diisopropyloxyphosphorylaminoacids(N-DIPP-AA),O-phospho-andO-diisopropyloxyphosphorylaminoacids(O-DIPP-AA)werestudiedandcomparedtoN-DIPP-AA.Thefragmentationpathwaysof[M+H]^+,[M+Na]^+and[M-H]^-ionsofphosphorylaminoacidsweresummarized.Inadditiontoseveralsimilarpatterns,eachofthemshoweditscharacteristicfragmention.

简介：Globozoospermia是round-headed精子与不在的acrosome，异常的原子膜和midpiece缺点描绘的teratozoospermia的一种严重形式。Globozoospermia被100%round-headed精子的存在在精液分析上诊断，并且有这个条件的病人绝对是不肥沃的。这研究的目的是在在人的round-headed和正常精子之间的蛋白质表示调查差别。二维(2-D)荧光差别胶化电气泳动(DIGE)结合了集体spectrometry(MS)在这研究被使用。超过61个蛋白质点在每配对的normal/round-headed比较被分析，用与一个内部标准一起的DIGE技术。总共，双人脚踏车团spectrometry(MS/MS)识别的35个蛋白质点展出了重要变化(配对的t测试，P<0.05)在在正常和round-headed精子之间的表示水平。九蛋白质的一个总数被发现是upregulated，26蛋白质被发现与正常精子相比是在round-headed精子的downregulated。差别表示了我们识别了的蛋白质可以在许多细胞的过程和结构有重要角色，包括精子发生，房间骨骼，新陈代谢和精子活动性。

简介：Inthiswork,areliableandsensitivemethodfordetectingpolybrominateddiphenylethers(PBDEs)hasbeendevelopedbythecombinationofliquid–liquidextractionandgaschromatography–massspectrometry.PBDEswereextractedfromalargevolumeofwaterbyliquid–liquidextractionandpurifiedbysilicagelchromatography.Inordertoreducethedeviation,dibromobiphenylwasexploitedastheinternalstandardtominimizedifferencesamongtheinjections.Thequantificationwasperformedusinganexternalstandard.Goodlinearcorrelationcoefficients(>0.991)andawidelinearityrange(1.0–500.0ng/L)indicatedthesteadinessoftheproposedmethod.Moreover,thesatisfactoryrecovery(>75%)suggestedthatsuccessfuldeterminationofPBDEsinriverwaterhadbeenachieved.Furthermore,thedeductionbehaviorofPBDEsinriverwatercouldbeinferredaccordingtotheresults.

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简介：Serine,oneofthenonessentialaminoacids,isofprincipalinterestbecauseofitscapabilitytoformmagic-numberionicclusters,whichprovidearemarkablepreferenceforhomochirality.WithL-asparticacidastheprecursor,thisstudyprovidesexperimentalevidenceforserineformationinweakacidifiedaqueoussolutionsinthepresenceofiron,withexposuretosunlight,whichsimulatesthenaturalconditionsoftheprebioticaqueousenvironment.Theresultantmixtureisdirectlyanalyzedviadesorptionelectrosprayionizationmassspectrometry(DESI-MS),withoutanysamplepreseparation.Theserinemonomerissuccessfullydetectedasprotonatedmolecules,givingapeakatm/z106,whichisconfirmedbytheMS/MSfragments.Protonatedserineoctamer(m/z841)isalsoobservedwithsignificantabundanceintheMSspectraandisconfirmedbytheMS/MSdata,whichshowstheformationoftheserineoctamerbyasynthesizedserineintheresultantmixture.ItisalsofoundthattheserineoctameryieldedequivalentabundanceintheDESImassspectrainawidepHrange(pH=1-5),andthatexistenceofferroussaltandsunshineareessentialfortheconversionofasparticacidtoserineintheacidicwatersolution.

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