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原標(biāo)題：70岁老太把腿岔开给老头摸

　　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)??。??　　嬰??(ying)幼??(you)兒??(er)期??(qi)(0～3歲??(sui))??，新??(xin)生??(sheng)兒??(er)免??(mian)疫??(yi)系??(xi)統(tǒng)??(tong)像?(xiang)一??(yi)支??(zhi)未??(wei)經(jīng)??(jing)實??(shi)戰(zhàn)??(zhan)的??(de)“新??(xin)兵??(bing)部??(bu)隊??(dui)”??，先??(xian)天??(tian)性??(xing)免??(mian)疫?(yi)(如??(ru)中??(zhong)性??(xing)粒??(li)細??(xi)胞??(bao)、巨??(ju)噬?(shi)細??(xi)胞??(bao))活??(huo)性??(xing)高??(gao)??，但??(dan)皮?(pi)膚??(fu)、黏??(nian)膜?(mo)屏?(ping)障??(zhang)薄??(bo)弱??(ruo)??，易??(yi)受??(shou)病??(bing)毒??(du)(如??(ru)呼??(hu)吸?(xi)道??(dao)合??(he)胞??(bao)病??(bing)毒??(du)、輪??(lun)狀??(zhuang)病??(bing)毒??(du))侵??(qin)襲??(xi)??。??此??(ci)時??(shi)主?(zhu)要??(yao)依??(yi)賴??(lai)母??(mu)體??(ti)通?(tong)過?(guo)胎??(tai)盤??(pan)和??(he)母??(mu)乳??(ru)傳??(chuan)遞?(di)的??(de)抗??(kang)體??(ti)(如??(ru)IgG、IgA)提??(ti)供??(gong)保??(bao)護?(hu)??。。