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1.
濒危植物矮牡丹的生态位研究 总被引:26,自引:2,他引:24
矮牡丹 (PaenoniasuffruticosaAndr .var .spontaneaRehd .)属毛茛科 (Ranunculaceae)芍药属植物[1] ,为我国特有种 ,仅分布于山西稷山马家沟、永济水峪口 ,陕西延安万花山、华阴二仙桥等地 ,其花具有一定的观赏价值 ,根作“丹皮”入药 ,既是宝贵的花卉种质资源 ,又是优良的药材资源 ;且为栽培牡丹的原始种之一[2 ] 。由于自然植被的破坏和 2 0世纪 60年代的大量采掘 ,致使矮牡丹分布范围日益缩小。目前已被列为国家三级保护植物。生态位的概念自Grinell的“生物在栖息地所占… 相似文献
2.
牡丹品种朱砂垒(Paeonia suffruticosa Andr.cv.Zhushalei)在冬季室内催花过程7种内源激素含量变化不同。玉米素核苷(Z+AR)、生长素(IAA)和赤霉素(GA3)的含量在花生长发 处于较高水平;而脱落酸(AB)、异戊烯基腺苷(IP+IPA)、二氢玉米素核苷(DHZ+DHZR)、赤霉素(GA4)的含量低于上述3种内源激素。激素平衡方面,GAs/ABA、CTKs/AB 相似文献
3.
Epilepsyisoneofthecommondiseasesduringchildhoodinclinicalpractice.Becauseofcomplexetiology,molecularmechanismsofepileptogenesisarenotfullyclear.Asweknowepilepsyiscausedbyimbalancebetweenexcitationandsuppressionofthebrain.Ithasbeenshowninhumanandanimalm… 相似文献
4.
Proteincrystalgrowthhasbeenofgreatimportanceinexploitationofstructuresofbiologicalmacromolecules.Themicrogravityenvironmentinspaceisanidealplacetostudythecomplicatedproteincrystallizationprocessandtogrowgoodqualityproteincrystals.Sincethe1980s,noticeabl… 相似文献
5.
Telomereistheessentialgeneticlocusattheendsofalleukaryoticchromosomes.TheywereproposedtocapchromosomespreventingtheendtoendfusionsbetweenbrokenendsandcontinualterminalDNAlossduringreplication.Theyalsohaveinfluencesonmembranechromosomeinteractionandthe… 相似文献
6.
Apoptosisorprogrammedcelldeathhasrecentlybeenrecognizedasamodeofcelldeaththatcanbeactivatedinmanysystemsbyavarietyofchemicalandphysicalstimuli.Observationfromseverallaboratoriesindicatedthatmanyanticanceragentscaninduceapoptosisindifferenttypesofcell[… 相似文献
7.
Untilnow,allmachiningmethodsusedarephysicalorchemicalorphysicochemical.Thetechnologysystemofnaturalsciencecanbeclassifiedintothefollowingthreesubsidiarysystems:physics,chemistryandbiology.Thereforeabiologicalmachiningtechnologywillbeabrandnewbranchinma… 相似文献
8.
生态学的精神价值 总被引:1,自引:0,他引:1
生态学的精神价值陈清硕(江苏农学院扬州225001)SpiritualValueofEcology¥.ChenQingshuo(JiangsuAgriculturalCollege,Yangzhou225001):ChineseJournalofEcology,1993,12(3):68-72.Thispaperdescribesthefunctionsofecologyintheprogressofsocialideologyandcivilization.Ecologyhelpsbringintobeingtheconstructionofascientificworldoutlookandincreasetheecologicalconscious-nessofmankind.Italsosuppliesatotaldevelopmentalpointofviewforthesocietyandprovidesagreataestheticvalue.Thespiritualvalueofecologyshouldneverbeneglected.Keywords:socialecology,ecol 相似文献
9.
Breeding technology of alloplasmic wheat 总被引:4,自引:0,他引:4
Thenucleiofcultivatedwheatcouldbetransferredintocytoplasmofheterogenicspeciesorgeneraviasubstitutionbackcrossandothertechniques,thusTriticinaeexhibitswidegeneticdiversityofcytoplasm.Thisdiversityhadboththeoreticandbreedingvalueandcouldbeusedinalloplas… 相似文献
10.
Differential effects of Ca2+ and Mg2+ on endonuclease activation in isolated promyelocytic HL-60 cell nuclei 总被引:1,自引:0,他引:1
Apoptosisorprogrammedcelldeath(PCD)isaprocessofcelldeletionwhichoccursinresponsetoanumberofcytotoxicandphysiologicallyrelevantstimuli.Thisprocessischaracterizedbyseveralearlymorphologicalterationsincludingplasmaandnuclearmembraneblebbing.Endogenousendo… 相似文献
11.
Membrane molecules in induction of apoptosis of thymocytes by mouse thymic dendritic cells which express Fas ligands 总被引:6,自引:0,他引:6
Apoptoticthymocytesweredetectedinsituinthethymus[1],whiletheeffectsofthymicstromalcellsontheprocessofcelldeathofthymocytesarestillunclear.Wepreviouslyfoundthatmousethymicdendriticcells(MTSC4)enhancedtheapoptosisofthymocytesinvitro[2],andtheseeffectsweredep… 相似文献
12.
Alan Walker 《人类学学报》2002,(Z1)
1 IntroductionAmongthefourMiocenehominoidsitesofKaiyuan ,Lufeng ,YuanmouandBaoshaninYunnanProvinceofChina ,LufengandYuanmouaretherichestfossilsites .Sinceitsfirstdiscoveryin 1 975,manycolleaguesaroundtheworldhavebeeninvolvedinthestudyofLufengpithecusfossils .However,noagreementhasbeenreachedontherelationshipofLufengpithecustootherMiocenehominoidsfoundaroundtheworldoronitsphylogeny .WuRukangbelievesthatthereareaseriesofmorphologicaldif ferencesbetweenLufengpithecusandtheSivapithecusspecimensfoundinTurkeyandP... 相似文献
13.
陆生脊椎动物生态学研究的过去、现在和将来(前苏联科学院动物进化形态学与生态学研究所,莫斯科)Past,PresentandFutureofEcologicalResearchonTerrcstrialVctebratcs¥.(InstituteofAnimalEvolutionaryMorphologyandEcology,theFormerAcademyofSclencesofSovietUnion).ChineseJournalofEcology,1993,12(4):66-71。Thispaperdescribesthemainstages,directionsanditemsofecologicalresearchintheformersovietU-nion.EcologicalresearchinthecountrywasrestrodedbymanysuUectiveandoUectivefactorsandstilllagsbehindtheworldlevelinmanyaspectssuchaspopulationdynamicstheory,communityresearch,eco- 相似文献
14.
Nicotinic acetylcholine receptor is involved in acetylcholine regulating stomatal movement 总被引:4,自引:0,他引:4
Receptor,theprimarysiteofcellperceivingexternalsignals,controlsthecommunicationbetweencellsandenvironment[1].Acetylcholineisanimportantneurotransmitterinvolvedinthetransmissionofsignalsatjunctionsbetweennervesandbetweennerveandmuscle.Theactionofacetylch… 相似文献
15.
Themicroenvironmentconstitutedbythymicstromalcellsisanimportantsiteforthedevelopmentofthymocytes.95%ofthymocytesdieinthethymuseveryday,inthewayofapoptosis[1].Thecelldeathismainlycausedbythedefaultofpositiveselectionandtheactionofnegativeselectionswhichar… 相似文献
16.
持续农业与中国的生态农业 总被引:6,自引:0,他引:6
持续农业与中国的生态农业李萍萍,章熙谷(南京农业大学农学系,210014)SustainableAgricultureandChina’sEcologicalAgriculture¥.LiPingping;ZhangXigu(NanjingAgricul-turalUniversity,210014).ChineseJournaJofEcolegy,1993,12(2):16-18.Thebackground,conceptandcharacteristicsofsustainableagriculturearediscussed,anditssimilaritiesanddifferencestoChina’secologicalagriculturearedescribed.It’sconsideredthatChina’secologicalagri-cultureisaconcretereflectionofsustainableagricultureandasuccessfulmodelforagriculturaldevelop-ment.Keywords:sustainableagricult 相似文献
17.
Invasionandmetastasisarethemostimportantcharacteristicsofmalignanttumor.TheoverexpressionandincreasingactivityofcollagenaseIVintumortissueshavebeenconsideredasoneofthemainfactorsinvolvedintumormetastasis[1].IthasbeenthoughtthattheincreasingcollagenaseI… 相似文献
18.
Inrecentyears,theresearchofusingmammaryglandbioreactorstoproducelargeamountsofhumanpharmaceuticalproteinsdrawmoreandmoreattentionwiththedevelopmentoftransgenictechniques.Transgeneexpressioninmilkoffersseveralpotentialadvantages:proteinssecretedinmilk,w… 相似文献
19.
Threeextrinsicpolypeptides,whicharelocatedontheinnersurfaceofthylakoidmembrane,playessentialrolesinmaintainingthephotosyntheticevolutionofoxygen.Theyaregenerallyrecognizedasliablecomponentsofthephotosyntheticapparatus,andcanbereleasedbyavarietyofphysic… 相似文献
20.
Wheathaploidcanbeproducedbyembryorescueafterwheatandmaizecrosssincethemaizechromosomesarerapidlyeliminatedfromtheearlyzygoticembryos[1,2].Usually2%—5%ofwheatdoubledhaploidshowsagronomicvariations,butnoobviousmorphologicaltraitfrommaizeisobserved.Theywereco… 相似文献