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1.
INTRODUCTIONAnAdeno associatedvirus(AAV)particleiscomposedofthreestructuralproteinsandalin ear ,single strandedDNA (ssDNA)genomeofapproximately 4 .7kb .AAVisadefectivehu manparvovirusthatnormallyreplicatesproduc tivelyonlyinthepresenceofhelperfunctionsprovide…  相似文献   

2.
NTRODUCTIONAftermuchresearchandsomesuccessfulap plicationsofArtificialNeuralNetwork (ANN)tocontrolsystems,ANNhasbecomeoneoftheim portanttoolstoshowtheintelligenceofthehu manbrain .SinceANNcanbeusedtodescribeanynonlinearcontinuousfunction ,ithasdrawnmuchat…  相似文献   

3.
INTRODUCTIONAntisenseoligodeoxynucleotides (ASODN )caninhibittranscriptionandinterferewithspe cialgeneexpression .AfixedpointontheK rasgenewithhighmutationrateinpancreaticcarci nomaoffersanintracellulartargetforpancreaticcarcinomagenetherapywithASODN (Cai…  相似文献   

4.
浅议计算机辅助教学   总被引:1,自引:0,他引:1  
ComputerAssistedlnstruction (CAI)isthetermusedtodescribecomputerprogramsdesignedforteaching .ItisimportantnottoconfusethistermwithCALL(ComputerAssistedLanguageLearning)———thecatchalltermfordiffer entformsofL2instructionaccomplishedwiththeuseofcomputers.Fo…  相似文献   

5.
INTRODUCTIONItiswellknownthatinfreeradicalpolymerization,thediffusioncontrolledprocessesstronglyinfluencetherateofpolymerizationandthepropertiesoftheproducedpolymer.Anumberofmodelsweredevelopedtodescribethisphenomenaquantitatively(Achiliasetal.,1988;Achil…  相似文献   

6.
IntroductionTheRoadNotTakenRobertFrostTworoadsdivergedinayellowwood ,AndsorryIcouldnottravelbothAndbeonetraveler ,longIstoodAndlookeddownoneasfarasIcouldTowhereitbentintheundergrowth ;Andhavingperhapsthebetterclaim ,Thentooktheother,asjustasfair ,Becausei…  相似文献   

7.
从一个例子谈起 已知△ABC的三个内角A、B、C满足 :A C =2B ,secA secC =- 2secB ,求cos A -C2 的值 .解 由A C =2B ,得A C =12 0° ,B =6 0° .∵ secA secC =- 2secB ,∴ cosA cosC =- 2 2cosAcosC ,2cos A C2 cos A -C2=- 2〔2cos2 A -C2 - 1 cos(A C)〕 ,即  4 2cos2 A -C2 2cos A -C2 - 32 =0 .因 - 324 <- 1,故解得cos A -C2 =22 .1 关于解题思维表现的分析上例中 ,条件是三角形三内角的一个关系式和有关这些角的一…  相似文献   

8.
我们把三边边长成等差数列的三角形叫做等差三角形.它有一个重要的性质如下:定理 在△ABC中,角A、B、C的对边分别为a、b、c,若a、b、c成等差数列,则有tgA2tgC2=13.证明 由题意知 2b=a+c,由正弦定理得 2sinB=sinA+sinC,∴ 4sinA+C2cosA+C2=2sinA+C2cosA-C2.又∵ sinA+C2≠0,则有2cosA+C2=cosA-C2,即 2cosA2cosC2-2sinA2sinC2=cosA2cosC2+sinA2sinC2,∴ 3sinA2…  相似文献   

9.
1 Introduction IntheimplementationofCIMSinenterprises,thedevelopmentoftheCAD/CAMtechnologyandtheap pearanceofmatureCAD/CAMsoftwareprovidereliableandefficientdesigntoolsfortheexploitationanddevel opmentofproducts.UGII (aCAD/CAMsoftwareofEDScorporation)hasb…  相似文献   

10.
1 Introduction A generalizedinversematrixPad啨approximant(GMPA)isintroducedonthebasisofscalarproductofmatricesinRef.[1].TheexpressionofGMPAisoftheformofmatrixnumeratorandscalardenominator ,whichisdifferentfromthatofBoseandBasu[2 ] .Ascomparedtotheexistingmatr…  相似文献   

11.
A study of passive solar house design   总被引:1,自引:0,他引:1  
AStudyofPasiveSolarHouseDesignWangWei(ScholofArchitecturalEngineering)AbstractThispaperdealswiththeinvestigationoftheprincipl...  相似文献   

12.
ThevarietyofEnglishspokenintheUSAiscalledAmericanEnglish .AmericanEnglishgrewoutofBritishEnglishofthe 17thcentury.WiththefurthergrowthoftheUnitedStates,AmericanEnglishhasevolvedfroma“colonialbranch”toavariantorna tionalstandardofEnglish .Thecharacteristic…  相似文献   

13.
INTRODUCTIONRibozymewasfirstdescribedbyCechandAltmanin 1 981 .ThisformofRNAhadhighlyspecificendonucleaseactivitiestoRNA (Krugeretal.,1 982 ) .Ribozymeshavethreestructures:hammerhead ,hairpinandaxeribozymes.Amongthem ,thehammerheadribozymehasasimplersecondarystruc…  相似文献   

14.
AAsinglemother,LiRuizhiranintoseriousfinancialproblemshalfayearago .Herformerhusband ,whoshedi vorcedin 1 990refusedtopaythemoneyhepromisedfortheirson .Asanordinaryworker,shecouldnotearnenoughtosupporthersonwhoisnowacollegestudent.Whatwasshetodo ?Afterprivate…  相似文献   

15.
Aluminum AlloysTX1IntroductionFe-Alintermetalicshavegreatpotentialitiesforstructuralapplicationsowingtotheirgoodmechanicalprop...  相似文献   

16.
OBSTACLE DETECTION BY ALV USING TWO 2D LASER RANGE FINDERS   总被引:6,自引:0,他引:6  
INTRODUCTIONObstacleavoidanceisanessentialtaskoftheALV .Toachievethis,aquickandreliablede tectionofobstaclesisveryimportant.Severalclassesofactivesensorscanbeusedforthispur pose .Alaserrangefinder (LRF)cansuitablybeusedtodetectobstaclesaheadoftheALV .3DLRFs…  相似文献   

17.
DynamicalStabilityofFiniteAnisotropicPanelswithElipticalCutoutsandCracksZhaoQi(ShanghaiInst.ofAppliedMath.&Mech.)AbstractAnap...  相似文献   

18.
1 Introduction Itiswellknownthatmetalhydridesareanidealmediumforhydrogenstorageduetotheirhighdensityandhigh purityofhydrogen .However ,allknownconventionalmetalhydrides ,includingintermetalliccompoundsAB5,AB2 ,andAB ,havereversiblegravi metricH densitiesnomo…  相似文献   

19.
《河北自学考试》2000,(9):33-37
Ⅰ .VocabularyandStucture (1 0 points,1 pointforeach)1 .Almosteverythingamanagerdoes  deci sions;indeed ,somesuggestthatthemanagementpro cessisdecisionmaking .[A]imposes[B]improvises[C]involves[D]indi cates2 .Astronomersandscientiststhinkthatablackholeisaregionofspace…  相似文献   

20.
OntheEstrangementinTheMetamorphosisAnApproachfromthePerspectiveofAestheticsofReceptionYangxiangKafkasmasterpiece,TheMetamo...  相似文献   

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