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原標(biāo)題：欧美一区二区三区久久综合

學(xué)習(xí)快評丨qibao666888　　動??(dong)態(tài)??(tai)平??(ping)衡??(heng)??，免??(mian)疫??(yi)系??(xi)統(tǒng)??(tong)的??(de)“終??(zhong)生??(sheng)任??(ren)務(wù)??(wu)”　　第??(di)一?(yi)道??(dao)防??(fang)御??(yu)是??(shi)物??(wu)理??(li)屏?(ping)障??(zhang)??，比??(bi)如??(ru)皮??(pi)膚?(fu)和??(he)黏??(nian)膜??(mo)??，像??(xiang)城??(cheng)墻??(qiang)一??(yi)樣??(yang)覆??(fu)蓋??(gai)體??(ti)表??(biao)??，通?(tong)過??(guo)汗??(han)液??(ye)、皮??(pi)脂??(zhi)和??(he)黏?(nian)液?(ye)中??(zhong)的?(de)抗??(kang)菌??(jun)成??(cheng)分??(fen)??，直??(zhi)接??(jie)阻??(zu)擋??(dang)細(xì)?(xi)菌??(jun)、病??(bing)毒??(du)入??(ru)侵??(qin)；比??(bi)如??(ru)呼??(hu)吸??(xi)道??(dao)纖??(xian)毛?(mao)??，如??(ru)同?(tong)護(hù)??(hu)城??(cheng)河??(he)的??(de)“清??(qing)道??(dao)夫??(fu)”??，通??(tong)過??(guo)擺??(bai)動??(dong)??，將??(jiang)灰??(hui)塵??(chen)和??(he)病??(bing)原??(yuan)體??(ti)排??(pai)出??(chu)體??(ti)外??(wai)??。??。