简介：Itwasrecentlysuggestedthattheperiodicandfractalprecipitaionofcalciumsaltsandproteinsincholesterolgallstonesiscloselyrelatedtotheprocessofstoneformation.Thepresentstudyistomimictheprocessofgallstonegrowthinvitro.Wedemonstrateforthefirsttimethatathree-dimensionalstructureofperiodicrings(Liesegangring)and/orfractalpatternscanbeproducedbymetalionanddeoxycholateprecipitaitonwhicharesimilartogallstones.Precipitationinaperiodicpatternoccursmoreoftenthaninafractalstructure,UsingX-raydiffraction.polarizedlightmicroscope,Fouriertransform-infrared(FT-IR),andextendedX-rayabsorptionfinestructure(EXAFS),westudiedthepatternformationmechanismsofbothtypesofstructure.Theresultsindicatethattherateofnucleationinthecrystalgrowthisacrucialelementofaffectthepatternformation.Thepatternselectionbetweenperiodicandfractaltypedependsonthecrystalgrowthspeedandtherateofnucleation.