简介：为了进一步研究HIV-1外膜蛋白的结构和功能，获得足够量的糖蛋白，对HIV-1的外膜蛋白Env进行了修饰，利用PCR技术克隆目的基因，把Env基因构建到毕赤酵母Pichiapastoris表达载体中，把pPICZαB-Env表达载体转化到酵母中，根据基因重组技术，使Env基因和酵母基因组重组，筛选阳性重组子．

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简介：Thereactionof1-phenyl-3-methyl-4-benzoyl-2,5-dihydro-1H-pyrazol-5-one(PMBP)andmethyldithiocarbazate(mdtc)inmethanolresultsinformationofayellowcrystallinesolid,adductof1-phenyl-3-methyl-4benzoyl-2,5-dihydro-lH-pyrazol-5-oneandmethyldithiocarbazate.Whentheyellowsolidsweredissolvedinamixtureofmethanolandether(1:4),aredcrystal,whichisanoxidationproductoftheformer,wasobtainedbyallowingsolventtoevaporateforafewdaysatroomtemperature.TheX-rayanalysisoftheredcrystalindicatesthatitisanoveldisulfidewithaspecialstructurelikea“U”conformationinthesolidstate.

简介：α-Aminonitrileswerepreparedefficientlyfromanodiccyanationofα-aminoester.Theeffectofdifferentsolventsandelectrolyteswasstudied.Theotherbyproductswereanalyzed.

简介：选用30个结构多样的CaM抑制剂分子作为数据集，采用多元线性回归（MLR）方法及主成分回归分析（PCA）方法对每个化合物的194个分子参数进行回归分析，分别建立了各自的最优预测模型．结果表明：多元线性回归分析方法所建模型与主成分回归所建模型相对比，发现逐步筛选法为最优建模方法．该方法所建模型统计结果良好（R^2=0．952，SEE为0．289），应用于检验集时结果也比较令人满意（R^2=0．941，SEP为0．295），模型表现出较强的可靠性和预测性．

简介：Wehavesuccessfullysynthesized1-(2′-Phenyl)cycloproply1-2,3-epoxypropan-1-ol3,whichwillbeappliedtothekineticsstudyofoxiranylcarbinylradical.

简介：Treatmentof4-amino-3-(1-aryl-5-methyl-1,2,3-triazol-4-yl)-5-mercapto-1,2,4-triazoles/2-amino-5-(1-aryl-5-methyl-1,2,3-triazole-4-yl)-1,3,4-thiadiazoleswithbenzaldehyde,acetoneandω-bromoacetophenonewastestedandcompared.ThetitlecompoundsSchiffbases,amides,imidazolo[2,1-b]-1,3,4-thiadiazolesand7H-s-triazolo[3,4-b]-1,3,4-thiadiazineshavebeenconfirmedbyelementalanalyses,^1HNMR,IRandMSspectra.AllthecompoundshavealsobeenscreenedfortheirantibacterialactivitiesagainstB.subtilis,S.aureusandE.coli.

简介：利用Gaussian03软件包,采用多种方法和多种基组对CCl和CCl2分子的基态结构进行优化计算,优选出B3P86/6-311＋G（3df）方法对CCl分子进行计算得到基态为X2Π、键长RCCl=0.16442nm,谐振频率ωe=886.3062cm-1;优选出B3P86/6-311G（2df）方法对CCl2分子进行计算得到基态为X1A1,平衡核间距RC—Cl=0.17194nm、键角βCl—C—Cl=109.2457°、离解能De=3.4635eV,并计算出了谐振频率和力常数,其结果与实验值符合很好.并采用多体展式理论推导出CCl2自由基的解析势能函数,其等值势能图准确呈现出CCl2分子的结构特征及能量变化曲线.由此讨论了Cl＋CCl和C＋ClCl分子反应的势能面特征.可用于研究该分子的微观反应动力学特性.

简介：Aseriesofnovel1H-benzimidazol-1-ylacetatesand1H-benzimidazol-1-ylpropionatescontaining1H-1,2,4-triazolemoietyweresynthesizedundermicrowaveirradiationbymulti-stepreactions,inyieldsof87-94%.TheirinvitroantifungalactivitiesagainstBotrytiscinereaandSclerotiniasclerotiorumwereevaluatedbymycelialgrowthratemethod.AllthetargetcompoundsexhibithighactivitiesagainstB.cinereawiththeEC50valuesof7.96-21.74μg/mL,higherthanthatofcarbendazim.

简介：Thehydrolysisreactionof(±)-2-acetamido-3-hydroxy-1-(4-nitrophenyl)-1-propanone[(±)-1],anintermediateofchloramphenicol,wasstudiedandthreedifferentproductswereobtainedrespectivelyunderdifferentreactionconditions.Theresolutionofhydrolysisproduct(±)-2-amino-3-hydroxy-1-(4-nitrophenyl)-1-propanone[(±)-3]wascarriedout.Aprocessofcrystallization-inducedasymmetrictransformationwasobservedandupto76%oftheopticallypureenantiomerwasobtainedintheresolutionof(±)-3.

简介：Apracticalprotocoltoobtain1,1'-binaphthyl-2,2'-diaminewasdevelopedfrom2-naphtholand2-naphthylhydrazineundermildconditions:solvent-free,125-130℃,atmosphericpressure.Theconvenientproceduremakestheprocessamenableforlarge-scalesynthesisoftheversatilecompound.

简介：New[1+1]and62-membered[2+2]Schiffbasemacrocyclescontaininga2,6-diamidopyridinesubunithavebeensynthesizedbycondensationreactionoftheprecursorspyridine-2,6-dicarboxamideand1,10-bis(20-formylphenyloxy)decaneinthepresenceofphosphoricacidviaaone-potprocess.Thecyclocondensedproductswereeffectivelyisolatedbygelcolumnchromatographyandcharacterizedby~1HNMR,FTIR,massspectrometryandX-rayanalysis.Thetwomacrocycleshaveatwistedstructure,andnotanopen‘circular’conformationinthesolidstate.

简介：体外循环后精确控制鱼精蛋白用量对抗肝素,是预防鱼精蛋白中毒性反应的关键环节.由于血液中存在高浓度的亲脂性钾离子（如血液中钾离子的浓度约为5mg/L,血细胞中钾离子的浓度高达150mg/L）,而传统的聚阳离子选择性电极膜相中含有阳离子位点,在这种情况下,钾离子很容易进入聚合物膜相而干扰鱼精蛋白阳离子的测定.为了克服血液中钾离子的干扰,开发了肝素活化的聚阴离子选择性电极技术,成功实现了鱼精蛋白聚阳离子的检测,高浓度的钾离子不干扰测定.在最佳条件下,该电极对鱼精蛋白聚阳离子的检出限可达0.1mg·L-1,线性范围为0.5-10mg·L-1.

简介：以双稳态振荡器耦合而成的具有小世界拓扑结构的网络为研究对象，重点研究了该体系在周期弱信号和乘性高斯白噪声的共同作用下，振荡器之间的耦合强度与网络拓扑结构的无序度对于网络动力学行为的影响．结果显示噪声可以诱导产生随机共振现象，在适中的耦合强度下增加体系拓扑的无序度可以使整个体系的随机共振现象得到加强．另外，研究表明体系中存在着一组最优的耦合强度和拓扑无序度，在它们的协同作用下体系能够最有效地检测到外界的弱信号．

简介：ＳＹＮＴＨＥＳＩＳＡＮＤＡＮＴＩ－ＨＵＭＡＮＩＭＭＵＮＯＤＥＦＩＣＩＥＮＣＹＶＩＲＵＳ－１（ＨＩＶ－１）ＡＣＴＩＶＩＴＹＯＦ９－（２－ＰＨＯＳＰＨＯＮＹＬＭＥＴＨＯＸＹＥＴＨＹＬ）ＡＤＥＮＩＮＥ（１）ＡＮＤＩＴＳＲＥＧＩＯＩＳＯＭＥＲ３－（２－ＰＨＯ...

简介：本文通过对蛋白质结构基因的统计分析,建立了一个较精确的蛋白质二级结构的预测方法.我们不仅给出了一套α-螺旋及β-片层的构象参数和构象势,同时也给出了一整套的结构断裂参数。本文建立的基因密码方法对α-螺旋和价片层预测的成功率分别为88.0%和86.9%。

简介：TwopossiblereactionmechanismsofVS~+(~3∑~-,~1Γ)withCOinthegasphasehavebeenstudiedbyusingB3LYP/TZVPandCCSD(T)/6-311+G(3dr,3pd)methods:theO/Sexchangereaction(VS~++CO→VO~++CS)andtheS-transferreaction(VS~++CO→V~++COS).Thetworeactionsproceedviatwo-stepandone-stepmechanism,respectively.ThebarriersofthetripletandsingletPESsare30.6and50.9kcal/mol,respectively,forO/Sexchangereactionand7.3and50.2kcal/mol,respectively,fortheS-transferreaction.Theresultsindicatethatthetripletgroundstatereactionismorefavorable,andtheS-transferreactionismorefavorablethantheO/Sexchangereaction,whichisingoodagreementwiththeexperimentalobservation.

简介：Fourteennew1-acyl-5-arylbiuretsweresynthesizedbythereactionofarylureaswithacylisocynantes.Thelatterwasobtainedfromacylchlorideandleadcyanateindichloromethane,usingpyridineascatalyst.Thestructuresofcompounds3a-nwereconfirmedbyIR,1HNMRandMSspectra.

简介：Thediffusionbehaviorofpolystyrenewithnarrowmolecularweightdistributionat20℃in1,4-dioxanewasinvestigatedbythephotoncorrelationspectroscopy.Thecumulantmethodwasemployedfortheanalysisoftheintensity-intensityautocorrelationfunctionmeasuredoverawiderangeofthescatteringvector.ThediffusioncoefficientDwasdeterminedasthefunctionofconcentrationCinthemolecularweightrangeof3.0×104-1.20×106.Inalowconcentrationrange,DwasfoundtobelinearlydependentonC,whichhasbeenfoundforsomeothersystems.ThedependenceofDonmolecularweightatinfinitedilutioncanbewrittenasanempiricalformulaD0=kDM-γM,theexponentγ(0.576±0.01)isingoodagreementwiththeresultofthescalingtheory.

简介：Promotedbystannoussalts,1,1,1-trichloro-2,2,2-trifluoroethanereactsreadilywithaliphatic,aromatic,andα,β-unsaturatedaldehydesgivingthecorrespondingalcoholsbearingaCF3CCl2-moietyingoodtoexcellentyields.ThesealcoholsarefartheroxidizedbyJonesreagentgivingthecorrespondingketonesinhighyields.