简介:Thesuddenoutbreakofsevereacuterespiratorysyndrome(SARS)in2002promptedtheestablishmentofaglobalscientificnetworksubsumingmostofthetraditionalrivalriesinthecompetitivefieldofvirology.WithinmonthsoftheSARSoutbreak,collaborativeworkrevealedtheidentityofthedisastrouspathogenasSARS-associatedcoronavirus(SARS-CoV).However,althoughtherapididentificationoftheagentrepresentedanimportantbreakthrough,ourunderstandingofthedeadlyvirusremainslimited.Detailedbiologicalknowledgeiscrucialforthedevelopmentofeffectivecountermeasures,diagnostictests,vaccinesandantiviraldrugsagainsttheSARS-CoV.ThisarticlereviewsthepresentstateofmolecularknowledgeaboutSARS-CoV,fromtheaspectsofcomparativegenomics,molecularbiologyofviralgenes,evolution,andepidemiology,anddescribesthediagnostictestsandtheanti-viraldrugsderivedsofarbasedontheavailablemolecularinformation.
简介:TaijiquanisamartialartofthehighestorderisculturallyetchedintheChineseheritageandentrenchedinwushupulpfictionandkungfumovies.Thereinliestheenigma.Thegentleslow-motionpracticecannotbemoreremotefromthespeedandpowerofcombat.AndaddingtothemystiqueisthepropositionthatTaijiquan'skungfuprowessisnotdrawnfromthephysicalstrengthofthemusculaturebutfromsome"innerstrength"orNeijin.ThissacredbeliefwasdesecratedwhenafighterthrashedaselfproclaimedTaijiquangrandmasterignominiouslyin10secondsinanopenmatch.Taijiquanwasthenderidedasaboguscombatart.TheincidentshakesthefoundationofTaijiquanandputsintoquestionsmanyofitstoutedclaims,whichchallengesthescientificquestoftheart.ThepaperconfrontstheissuedirectlybystudyingthemanifestationofNeijinintheframeworkofsciencetoprovideascientificbasisfortheart.Ittranscribestheyin-yangmetaphysicsthatregulatesTaijiquantrainingintermsofthealignmentofmuscleactionstobalanceandtounifymomentum,whichdevelopsthecorestrengthofNeijinandtheunderlyinglife-forceQienergy.Fromthisflowsthekungfumarvels,whichlieinthelivelinessandagilityofNeijin'sresponseandintheforceensuingthatisoftherightvectorvalues,allessentialinthefluidityofcombatapplication.ThemartialaspectofTaijiquanprovidesaconcreterepresentationofNeijin,whichgivesanexperientialinsightintothemultifacetedconceptofQi,andinturnapathwaytotheexplorationofQiinphysiologyandthusinQienergymedicine.
简介:ThisisthespecialissuedevotedtobioinformaticsresearchinSingapore.BioinformaticsresearchinSingaporestartedlargelyin1996whentheBioinformaticsCenter,NationalUniversityofSingapore,wasformed.Withthegovernment'seffortstoturnSingaporeintoapowerhouseofbiomedicalresearch,theGenomeInstituteofSingaporeandtheBioinformaticsInstituteofSingaporehavebeenestablishedsince2000.Recently,abioinformaticsresearchcenterwasalsoformedintheNanyangTechnologicalUniversity.Currently,therearealargenumberofbioinformaticsresearchteamsineachoftheseinstitutions.
简介:Themodulationandcontrolofgecko'sfootmovementswerestudiedelectrophysiologicallyinordertodesignthemotorcontrolsystemofagecko-mimicrobot.Inthisstudy(1)theanatomyoftheperipheralnervescontrollingthegecko'sfootmovementswasdetermined;(2)therelationshipbetweenthelimbnervesofthegeckoanditsfootmotorpatternswasstudied;(3)theafferentimpulsesofthenervesevokedbyrubbingthegecko'stoesandpalmwererecorded;(4)copyingthenaturalpatternsofmovementofthegecko'sfoot(abduction,adduction,flexion,andrevolution)anditslimbnervemodulationandcontrolmechanism,thenerveswerestimulatedundercomputercontrol,andtheresultsrecordedbyCCD.Resultssuggestthatgecko'sfootmovementscanbesuccessfullycontrolledbyartificialelectricalsignals.
简介:Thesandfishisalizardhavingtheremarkableabilitytomoveindesertsandinaswimming-likefashion.Themostout-standingadaptationstothismodeoflifearethelowfrictionbehaviourandtheextensiveabrasionresistanceofthesandfishskinagainstsand,outperformingevensteel.Weinvestigatedthetopography,thecompositionandthemechanicalpropertiesofsandfishscales.Theseconsistofglycosylatedkeratinswithhighamountofsulphurbutnohardinorganicmaterial,suchassilicatesorlime.Remarkably,atomicforcemicroscopyshowsanalmostcompleteabsenceofattractiveforcesbetweenthescalesurfaceandasilicontip,suggestingthatthisisresponsiblefortheunusualtribologicalproperties.Theunusualglycosylationofthekeratinswasfoundtobeabsolutelynecessaryforthedescribedphenomenon.Thescalesweredissolvedandreconstitutedonapolymersurfaceresultinginpropertiessimilartotheoriginalscale.Thus,weprovideapathwaytowardsexploitationofthereconstitutedscalematerialforfutureengineeringapplications.
简介:China'sFreeARTProgramwasinitiatedin2002asanemergencyresponsetosaveandimprovethelivesofAIDSpatientslivingmainlyinimpoverishedruralregionsofcentralChina.WithlittleexperienceinHIV/AIDStreatmentandcareandresourcelimitations,China'seffortstoprovidewidespreadaccesstofreeantiretroviraltherapyhasbeenaprocessfraughtwithdifficulty.However,theFreeARTProgramisprogressingfromanemergencyresponsetoastandardizedtreatmentandcaresystem.Thedevelopmentofnationalguidelines,trainingprograms,alaboratorysupportnetwork,anationalpatientdatabase,programsforspecialpopulationssuchaschildrenandpatientslivingwithcoinfections,andoperationalresearchhasimprovedthescopeandqualityofthefreetreatmentprogram.AsofJune30,2005,atotalof19,456patientsin28provinces,autonomousregions,andspecialmunicipalitieshadreceivedfreeART.ChallengesstemmingfromthenatureofChina'shealthsystemandpatientpopulationpersist,butwithstronggovernmentsupportandadiversesetofresources,Chinahasthecapacitytoovercomethesechallengesandtoprovidenationwideaccesstohighqualitytreatmentandcare.
简介:Naturalcomposites,formedthroughbiomineralization,havehighlyorderedstructureswhichhavebeenaptlyexploredforfunctionalapplications.Thoughtheroleoforganicphaseshasbeenwellunderstoodinbiomineralization,notenoughattentionhasbeenpaidtotheroleofbio-membraneswhichareoftenfoundencapsulatingthechamberinwhichmineralizationoccurs.Wehaveusedthenaturalproteinandsemi-permeablemembraneofchickeneggstogrowdifferentmaterialssuchasceramics,semi-metalsandmetalstounderstandtheroleofbio-membranesinbiomineralization.Weherereportthesuccessfulbiomimeticsynthesisofcalcite,cadmiumsulphide,andsilverhavinghomogeneousmorphologies.Wehavefoundthatthemembraneoperateslikeatunedgateway,playingasignificantroleincontrollingthemorphologyoftheinorganiccrystalsformedduringbiomineralization.
简介:通过对20世纪80年代以来具有代表性的华北夏谷区审(鉴)定的20个主栽谷子品种进行SSR标记多态性分析,研究了华北地区育成谷子品种的遗传多样性。49对引物在20个谷子品种中扩增出具有多态性的条带,共检测出142个等位变异,平均每个位点检测出的等位变异数为2.96个。标记位点多态性信息含量(PIC)变幅为0.0904~0.6896,平均为0.4168。20份材料间的遗传距离变幅为0.0173~0.9000,聚类分析将其分成3个类群,其中谷丰1号自成一类,表明谷丰1号的遗传距离较其他品种大。不同年代谷子品种间遗传距离分析结果显示,各年代品种之间的平均遗传距离由大到小依次是1980s>1990s>2000s>2010s,表明随着年代的递进育成品种的遗传差异减小,亲缘关系增近。
简介:Thecorona-likespikesorpeplomersonthesurfaceofthevirionunderelectronicmicroscopearethemoststrikingfeaturesofcoronaviruses.TheS(spike)proteinisthelargeststructuralprotein,with1,255aminoacids,intheviralgenome.Itsstructurecanbedividedintothreeregions:alongN-terminalregionintheexte-rior,acharacteristictransmembrane(TM)region,andashortC-terminusintheinteriorofavirion.WedetectedfifteensubstitutionsofnucleotidesbycomparisonswiththeseventeenpublishedSARS-CoVgenomesequences,eight(53.3%)ofwhicharenon-synonymousmutationsleadingtoaminoacidalternationswithpredictedphysiochemicalchanges.ThepossibleantigenicdeterminantsoftheSproteinarepredicted,andtheresultisconfirmedbyELISA(enzyme-linkedimmunosorbentassay)withsynthesizedpeptides.AnotherprofoundfindingisthatthreedisulfidebondsaredefinedattheC-terminuswiththeN-terminusoftheE(envelope)pro-tein,basedonthetypicalsequenceandpositions,thusestablishingthestructuralconnectionwiththesetwoimportantstructuralproteins,ifconfirmed.Phyloge-neticanalysisrevealsseveralconservedregionsthatmightbepotentdrugtargets.
简介:【目的】谷斑皮蠹是一种重要的检疫性害虫,在新疆周边多个国家分布,口岸检疫人员多次从进境货物中截获谷斑皮蠹,该虫对新疆的农业生产极具威胁。【方法】以谷斑皮蠹的16SrDNA基因为靶序列,用昆虫通用引物对4种供试皮蠹进行PCR扩增,将扩增产物进行克隆和测序,用生物软件设计检测谷斑皮蠹的特异性引物与探针。【结果】设计的特异性引物(TG-SNP-F/TG-SNP-R)及所建立的常规PCR方法能有效检测出谷斑皮蠹,其扩增产物的片段大小为250bp,灵敏度为3ng·μL^-1设计的特异性引物(TG-F/TG-R)和探针(TG-probe),以及所建立的实时荧光PCR方法,对谷斑皮蠹的检测特异性强,灵敏度达0.8fg·μL^-1【结论】建立的常规PCR方法和实时荧光PCR检测方法能够对谷斑皮蠹进行准确鉴定,为口岸检疫人员检测进境货物中携带的谷斑皮蠹提供技术支持。
简介:目的研究软骨多糖对S180荷瘤小鼠的作用,并探讨其抑瘤作用机制.方法采用小鼠肉瘤S180细胞建立动物腹水瘤模型,通过腹腔注射软骨多糖进行治疗,治疗期间抽取腹水瘤细胞进行细胞生物学分析.通过HE染色,流式细胞术、TUNEL法检测细胞形态学方面、细胞周期及凋亡率的变化情况;通过免疫荧光方法检测Fas、增殖细胞核抗原(PCNA)的表达情况.结果软骨多糖可以明显提高S180荷瘤小鼠的生存率,细胞形态学观察可见细胞出现细胞质浓缩、核固缩及凋亡小体等现象.软骨多糖作用后的S180细胞,其细胞周期被阻遏于G2/M期,Fas蛋白的表达水平于给药24h后升高,增殖细胞核抗原PCNA表达下降.结论软骨多糖可能通过影响肿瘤细胞周期和Fas、PCNA蛋白的表达来诱导S180细胞凋亡,并显著抑制肿瘤细胞的生长,延长S180荷瘤小鼠的生存时间,研究证实动物软骨多糖具有潜在的药用价值.
简介:Polyamines在在植物,而是他们的准确角色调整各种各样的发展过程被含有并且他们怎么管理这些过程尚待逃犯。我们这里报导浓密的Arabidopsis和矮子异种,bud2,哪个从编码S-adenosylmethioninedecarboxylases(SAMDC)的小基因家庭的一个成员的完全的删除的结果为在polyamine简历的不可缺少的中介的形成必要合成小径。bud2植物在开花期,根,和叶柄扩大了脉管的系统,并且polyamines的改变的动态平衡。bud2和samdc1的双异种,另一个SAMDC成员的击倒的异种,是胚胎致命,证明SAMDC为植物胚胎开始是必要的。我们的结果建议polyamines为更高的植物的正常生长和发展被要求。
简介:
简介:Chlorpyrifos(CPF)是用途广泛的organophosphate杀虫药剂。在昆虫的谷胱甘肽S-transferases(GST)是detoxification酶的一个家庭,他们在CPFdetoxification起关键作用。Spodopteralitura是在在世界上的热带、副热带的区域的最破坏的农业害虫之一。在这研究,从在S的gsts的46个唯一的抄本的37Slgsts。包括八以前报导的GST,lituratranscriptome数据被识别并且他们的表达式模式在易受影响并且12-generation-CPF-treated紧张被分析在CPF忍耐的尚不致命的剂量理解这些Slgsts的角色。结果显示S的成员。lituraGST总科能被区分进三个主要的组:包括六cytosolicSlgsts(SlGSTe1,SlGSTe3,SlGSTe10,SlGSTe15,SlGSTo2和SlGSTs5)和二microsomalSlgsts(SlMGST1-2和SlMGST1-3),一个组为在12-generation-treated和易受影响的紧张感应的CPF直接负责;第二组织,包括三cytosolicSlgsts(SlGSTe13,SlGSTt1和SlGSTz1)和一microsomalSlgst(SlMGST1-1),仅仅在12-generation-treated紧张被导致;第三组织,包括八cytosolicSlgsts(二epsilon,三个三角洲,一终止,一个希腊语的第六个字母和一未分类的Slgst),比在易受影响的紧张在12-generation-treated紧张更高是表示1.52-5.15-fold。
简介:荞麦13S球蛋白是荞麦种子中的一类主要贮藏蛋白。本研究选用荞麦属植物甜荞栽培种及其野生类型、苦荞栽培种及其野生类型、毛野荞、左贡野荞、细柄野荞和硬枝万年荞6个种共44份材料,进行PCR特异性扩增、测序得到荞麦13S球蛋白基因的保守片段序列。对序列进行差异分析,结果发现44份供试材料13S球蛋白基因片段的285个排列位点中不变位点为24个,多态性位点S为261个(含简约信息位点数198个和单型可变位点63个),序列总突变位点Eta为503个。野生甜荞种内13S球蛋白基因序列差异明显高于栽培甜荞,但野生苦荞种内13S球蛋白基因序列差异仅稍高于栽培苦荞。推测其一方面可能与繁殖方式有关,另一方面可能与荞麦驯化过程中通常只有少数野生型群体被驯化有关。系统聚类分析发现栽培甜荞与野甜荞亲缘关系近,与左贡野荞亲缘关系次之;栽培苦荞与野苦荞亲缘关系近,与毛野荞亲缘关系次之;细柄野荞和硬枝万年荞的13S蛋白基因片段序列差异较小,说明其亲缘关系较近。上述结果为荞麦属种间遗传多样性与进化关系研究提供了理论依据。
简介:土壤宏无脊椎动物在在澳大利亚的热带无树平原支撑生产和生物多样性起一个重要作用。例如,通过他们的foraging和嵌套的活动,白蚁再循环营养素和碳并且生产便于水渗入的土壤毛孔。挑战向前到份量上理解驾驶这的关系和进程。不同种类和宏无脊椎动物的功能的组在各种各样的风景过程起什么作用?是不同陆地管理的效果的,练习(例如,国内牛放牧,火)在为风景健康的这些关系,和后果上?这篇论文在北澳大利亚从研究论述初步的结果,检验在土壤宏无脊椎动物上放牧的陆地状况和国内牛的效果,并且为要用作一个工具恢复的白蚁的潜力在降级的区域玷污功能。在北澳大利亚,增加了降级似乎在差异和活动ofmacroinvertebrates与衰落被联系。白蚁看起来是最有弹性的组之一,与能够维持在降级的风景的活动的某种类。
简介:在这研究,我们描述从蚊子疟蚊属stephensi孤立的ribosomalproteinS7基因的部分genomic组织。开始558bp部分cDNAsequence作为长包含223bp的先锋信使rna顺序被放大intron。5''和3''结束序列用cDNA的特定的快速的扩大结束的结束(种族)被恢复聚合酶链反应。全身的cDNA顺序与能够长编码192氨基酸的一个开的读物框架长是914核苷酸有22174Da和pI的计算分子的质量的蛋白质点of9.94。蛋白质相同搜索揭示了>75%身份到另外的昆虫“sS7ribosomal蛋白质。顺序排列的分析揭示了几个高度保存的领域,其一个与原子本地化有关是人的rpS7的信号(NLS)区域。有趣地,有A的intron核苷酸顺序比较。gambiae作为与编码anduntranslated区域相比显示出保存的更小的度。象这一样,早在genomic组织和分析(EST)能在A的染色体注解帮助的cDNA/Expressedsequence标签上学习。stephensi,并且将可能以后被定序。