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1、末代沙皇尼古拉二世的公主斯塔西娅安娜-安德森1956电影”真假公主”10人类染色体畸变chromosomeaberrationAnytypeofchangeinthechromosomestructureornumber(deficiencies,duplications,translocations,inversions,etc.).Althoughitcanbeamechanismforenhancinggeneticdiversity,suchalterationsareusuallyfatalorill-adaptive,especially
2、inanimals.1.factorsinducingchromosomeaberrationA.IonizingradiationIonizingradiationproducesrearrangementsofthegenome.WhenirradiationoccursduringtheG0/G1phaseofthecellcycle,large-scalerearrangementsappearasexchange-typechromosomeaberrationsatthenextmitosis.Suchaberrationscanalte
3、rcellularphenotypes,andareimportantinvariousareasofbiology:Analyzingchromosomeaberrationshelpscharacterizerepair/misrepairpathwaysinvolvedintheprocessingofDNAdamage.Ionizingradiationhassomeuniquefeaturesasaprobeofsuchpathways.Comparedtoothergenotoxicagents,itproducescopiousquan
4、titiesofDNAdoublestrandbreaks(DSBs),anditstimingcanbecontrolledmoreaccurately.Moreover,initialradiationdamagehasadiscrete,stochasticcharacterthatcanbemodulatedbyusingdifferentkindsofradiation(e.g.a-particlesversusx-rays)havingdifferentionizationdensities.Thespectrumofdifferentr
5、adiation-inducedchromosomeaberrationsisinformativeaboutthegeometryofchromosomesduringinterphase,andviceversa.B.chemicalmutagenAkindofsubstances,suchasdrugsortoxins,thatcauseschromosomalaberrationsoflivingorganisms,orincreasetherateofmutation.Drugantitumordrug(抗肿瘤药物)环磷酰胺、氮芥、白硝安(
6、马利兰)、甲氨喋呤、阿糖胞苷等抗癌药物Tocolysis(子宫收缩抑制剂)drugwhichpreventpregnancyreaction(预防妊娠反应的药物)anti-epileptic苯妥英钠可引起人淋巴细胞多倍体细胞数增高agriculturalchemicalsSomeagriculturalchemicalscaninducechromosomeaberration,likephosphatepesticide.Industrialpoisons苯、甲苯、铝、砷、二硫化碳、氯丁二稀、氯乙烯单体FoodadditivePreservativ
7、e(防腐剂),pigment(色素),AF-2(硝基呋喃基糖酰胺),benzosulfimide(环己基糖精)。Cbiologicalmutagentoxoidsterigmatocystin(杂色曲霉素),Flavacin(黄曲霉素),clavacin(棒曲霉素)等virusGermanmeaslesvirus(风疹病毒),(hepatovirus)乙肝病毒,Measlesvirus(麻疹病毒),cytomegalovirus(巨细胞病毒)DMaternalageDown综合征与母亲年龄2.chromosomalaberrationsA.chrom
8、osomenumericalaberrationNumericalaberrationisachangein