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原標(biāo)題：袖珍幻女bbwxxxx

學(xué)習(xí)快評(píng)丨qibao666888　　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(shí)??(shi)戰(zhàn)??(zhan)的??(de)“新??(xin)兵??(bing)部??(bu)隊(duì)??(dui)”??，先??(xian)天??(tian)性??(xing)免??(mian)疫??(yi)(如??(ru)中??(zhong)性??(xing)粒??(li)細(xì)??(xi)胞??(bao)、巨??(ju)噬??(shi)細(xì)??(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(shí)??(shi)主??(zhu)要??(yao)依??(yi)賴??(lai)母??(mu)體??(ti)通??(tong)過(guò)?(guo)胎??(tai)盤(pán)??(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(hù)??(hu)??。。