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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(lài)??(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)???！　∠??(xian)天??(tian)性??(xing)免?(mian)疫??(yi)是??(shi)人??(ren)類(lèi)??(lei)與??(yu)生??(sheng)俱?(ju)來(lái)??(lai)的??(de)防??(fang)御??(yu)系??(xi)統(tǒng)??(tong)??，如??(ru)同??(tong)城?(cheng)堡??(bao)的??(de)第??(di)一??(yi)道?(dao)城??(cheng)墻??(qiang)和??(he)巡??(xun)邏?(luo)衛(wèi)??(wei)兵??(bing)??，能??(neng)在??(zai)病??(bing)原??(yuan)體??(ti)入?(ru)侵??(qin)時(shí)??(shi)迅??(xun)速??(su)反??(fan)應(yīng)??(ying)??。??。