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原標題：麻豆av一区二区三区

　　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??(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??(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)??。??　　T細??(xi)胞??(bao)的??(de)角??(jiao)色??(se)則??(ze)是??(shi)指??(zhi)揮??(hui)、“殺??(sha)敵??(di)”與??(yu)“維?(wei)穩(wěn)?(wen)”??。??比??(bi)如??(ru)輔??(fu)助??(zhu)T細??(xi)胞?(bao)??，扮?(ban)演??(yan)著??(zhe)“指??(zhi)揮??(hui)官??(guan)”角??(jiao)色??(se)??，通??(tong)過??(guo)釋??(shi)放??(fang)細??(xi)胞??(bao)因??(yin)子??(zi)??，激??(ji)活??(huo)B細??(xi)胞??(bao)和??(he)其?(qi)他??(ta)免??(mian)疫??(yi)細??(xi)胞??(bao)；細??(xi)胞??(bao)毒??(du)性??(xing)T細??(xi)胞??(bao)??，扮??(ban)演??(yan)著?(zhe)“殺??(sha)手??(shou)”角??(jiao)色??(se)??，直??(zhi)接??(jie)穿??(chuan)透??(tou)感??(gan)染??(ran)細??(xi)胞??(bao)??，注??(zhu)入??(ru)毒??(du)素??(su)將?(jiang)其??(qi)摧??(cui)毀??(hui)；調(diào)??(tiao)節(jié)??(jie)T細??(xi)胞?(bao)??，扮?(ban)演??(yan)著??(zhe)“維??(wei)穩(wěn)??(wen)員?(yuan)”角??(jiao)色??(se)??，防??(fang)止??(zhi)免??(mian)疫??(yi)反??(fan)應??(ying)過??(guo)度??(du)??，避??(bi)免??(mian)誤??(wu)傷??(shang)健??(jian)康??(kang)組??(zu)織??(zhi)??。。