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　　免??(mian)疫??(yi)系??(xi)統(tǒng)?(tong)的??(de)核??(he)心??(xin)使??(shi)命?(ming)不??(bu)是??(shi)“消??(xiao)滅??(mie)一??(yi)切??(qie)”??，而??(er)是??(shi)識??(shi)別??(bie)敵??(di)我?(wo)、清??(qing)除??(chu)威??(wei)脅??(xie)??。?　　在??(zai)人?(ren)類??(lei)演??(yan)化??(hua)的??(de)長??(chang)河??(he)中?(zhong)?，人??(ren)體??(ti)免??(mian)疫??(yi)系??(xi)統(tǒng)??(tong)猶??(you)如??(ru)一?(yi)座??(zuo)精??(jing)密?(mi)設(shè)祝(she)計??(ji)的??(de)防??(fang)御??(yu)工??(gong)事??(shi)?，其??(qi)運??(yun)作??(zuo)機??(ji)制??(zhi)既??(ji)展??(zhan)現(xiàn)??(xian)著??(zhe)生??(sheng)命??(ming)演??(yan)化?(hua)的??(de)智??(zhi)慧??(hui)?，也??(ye)蘊??(yun)含??(han)著??(zhe)醫(yī)??(yi)學(xué)??(xue)干??(gan)預(yù)?(yu)的??(de)啟??(qi)示??(shi)?。??猶??(you)如??(ru)一??(yi)個??(ge)“隱??(yin)形??(xing)盾??(dun)牌??(pai)”?，免??(mian)疫??(yi)防??(fang)御??(yu)遵??(zun)從??(cong)怎??(zen)樣??(yang)的??(de)層??(ceng)次??(ci)？??不?(bu)同??(tong)年??(nian)齡??(ling)的??(de)免??(mian)疫??(yi)特??(te)點??(dian)有??(you)哪??(na)些??(xie)？人??(ren)體??(ti)免??(mian)疫??(yi)平??(ping)衡??(heng)的??(de)本??(ben)質(zhì)??(zhi)又??(you)是??(shi)什?(shen)么??(me)？來??(lai)看??(kan)看??(kan)它??(ta)的??(de)運??(yun)作??(zuo)奧??(ao)秘??(mi)?。。