eciesforfishbreedinghasopenedupanewway. thepursuitofscienceisanever-ending,fish,amphibiansnaturallysuccessfulcloningenablescientiststolookintothemammal.scientistsattheunitedstatesandswitzerlandtooktheleadfromthegraymouseembryocellsinthenucleusremoved,replacedwiththenuclearblackmicefertilizedeggcell.infact,theblackmousespermnucleiinthefertilizedeggcellafterentering,theyrefinedtogetherwiththeeggnucleuswiththenuclearremoved.chinchillaembryoniccellnucleartransferpeopletothenuclearblackmiceafterthefertilizedegg,culturedinvitroforfourdays,andthenitisimplantedintheuterusofwhitemice,withhundredsofgray,blackandwhitesoaftertheoperation,whitemousefinallygavebirthtothreesmallchinchilla. february27,1996britishpublication"nature"magazinepublishedtheroslininstituteinedinburghwilmotresearchresultsandothers:afterthefailureof247times,theyhavebeeninthepreviousyearinjuly,calleda"dolly"thecloningfemalesheep. "dolly"sheepishowto"create"comefrom?wilmotandotherscholarsgive"black-facedsheepinscotland,"gonadotropininjectiontoovulationitreceivedeggsimmediatelyaftertheuseoffinestrawremovedfromtheeggcellnucleus,atthesametime,fromthreemonthsofpregnancy"funmulti-seatspecial"agesixewesoutofthebreastcellnuclear,nuclearimmediatelygiveawaythe"black-facedsheepinscotland,"theegg,thesurgeryiscomplete,withthesamefrequencyofelectricalpulsestostimulatetheexchangeofnuclearegg,sothat"scotlandblack-facedsheep"oftheeggqualityand"fun,multi-seatspecial"sheepmammaryglandcellnuclearcoordinate,sothatthe"assembly"cellsinvitrofertilizedeggsthatexperienceddivision,embryonicdevelopmentandtheprocessofformation,thenembryosskillfullyotherewesimplantedintheuterus.injulylastyear,this"care"ofsheepembryosinvitrotoformfinallygavebirthtoasmallsheep"dolly.""victoria"isnotaewe'seggandthespermcellsgongyangtheproductoffertilization,but"forthenucleareggs,"theresultofthedevelopmentstepbystep,itis"clonedsheep." "clonedsheep"ofthebirthofallcountriesintheworldcausedbytheshock,itisvaluableisthatforthesomaticcellintothenucleus,ratherthantheembryonicnucleus.theresultsshowthat:animalbodyintheimplementationofspecialfeatures,withaspecificformoftheso-calledhighdegreeofdifferentiationofcellsandthesamefertilizedeggdevelopintoacompleteindividualwithpotential.inotherwords,animalcellsandplantcells,butalsowithallof. humancloningtechnologywillbringgreatbenefits,forexample,theunitedkingdompplhasproducedemphysematreatmentofgoat'smilkcontainsthea-1antitrypsininsheep.thisgoat'smilkisthepriceofaliterof61000u.s.dollars.asheepislikeapharmaceuticalfactory,whatmethodscanbemosteffectiveandeasytomakethatsheepbreedingtoexpandit?thebestwayisto"clone."similarly,thenetherlands,phpcompanycanproducehumanlactoferrinsecretionofthecattle,bredbytheisraelilascompanycapableofproducingsheepserumalbumin,thehighvalue-addedlivestockbreedingeffective?theanswer,ofcourse,or"cloning." withthepublicanddonkeymareheterosiscanbeparticularlystronganimals-mule,mulescannotreproduce,thenhowtoexpandtheexcellentbreedingmule?isthebestwayto"clone",china'sgiantpandaisanationaltreasure,butthelowsuccessrateofnaturalmating,ithasbeenendangered.howtosavetheserareanimals?"cloning"ashumanbeingstoprovideapracticableway. cloninganimalsforresearchalsocancerbiology,immunologyresearch,researchersandotherpeople'slifeshouldnotbeunderestimatedtheroleofboth. itisundeniablethatthe"clonedsheep",forexample,haveattractedmanypeopleof"humancloning"ofinterest,forexample,wasconsideredtheavailabilityoftheirownintoanembryoniccellcloning,initsfrozenbeforeforming.onedayinthefuture,oneoftheirownorganswhenaproblemcanberemovedfromtheembryoswereculturedinthisorgan,andthenreplacehisownorgandisease,whichisusedforcloninghumanbeingswith"accessories." on"humancloning"thediscussionofareminderthatprogressinscienceandtechnologyisoneofthemarch悲喜交集.themoredevelopedscienceandtechnologytosocietythemoreextensiveandin-depthpenetration,themorelikelycausealotofrelevantethical,moralandlegalissues.iwouldliketousenobellaureates,renownedmolecularbiologistjdwatson,thentotheendofthisarticle:"canlookforwardtomanybiologists,especiallythoseengagedincloningresearchscientists,willseriouslyconsidertheimplicationsofit,andtoinitiateascientificdiscussion,thepeopleoftheworldforeducation." d.inordertogainandmaintaincompetitiveadvantageandusedtotakeaction. sensecanbesaidthatcompetitiveintelligencehasthreecorefunctions: ●earlywarningsystem(monitoring,tracking,itisexpected,found) ●decisionsupport(acompetitivebasis,productiondecision-making,newmarkets,technologyr&d) ●learningsystem(reference,comparison,managementmethodsandtools,toavoidrigid) competitiveintelligenceworkistheestablishmentofainformationsystemtohelpmanagersassessthecompetitorsandsuppliersinordertoimprovetheefficiencyandeffecti << 上一页 [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] ... 下一页 >>
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