27()Vol.2720076JournalofSouth2CentralUniversityforNationalities(HumanitiesandSocialScience)Jun.2007a(,201620):,,,,,:;;:G64:A:1672-433X(2007)20194202,,,,,,,,,:,,,,,,,,,;,,,,,,[1],,,,,,:,,,;,,,,,,,[2],,(2005),,,,1.,,491a:2007-05-10:(1970-),,,,,©1994-2007ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.:,,,,,,,,,,;,,,,,,,,(),,,,,,,,:[1].[J].,2004(5).[2].[J].(),2006(2).()59127:©1994-2007ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.