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學習快評丨qibao666888　　兒??(er)童??(tong)至?(zhi)青??(qing)少??(shao)年??(nian)期??(qi)(4～18歲??(sui))??，隨??(sui)著?(zhe)免??(mian)疫??(yi)系??(xi)統(tǒng)??(tong)逐??(zhu)漸??(jian)成??(cheng)熟??(shu)??，適??(shi)應?(ying)性??(xing)免?(mian)疫??(yi)(T細??(xi)胞??(bao)、B細??(xi)胞??(bao))開??(kai)始??(shi)發(fā)??(fa)揮??(hui)主??(zhu)力??(li)作??(zuo)用??(yong)??，能??(neng)針??(zhen)對??(dui)病??(bing)原??(yuan)體??(ti)產??(chan)生??(sheng)特??(te)異?(yi)性??(xing)抗??(kang)體??(ti)??。??但??(dan)免?(mian)疫??(yi)系??(xi)統(tǒng)??(tong)也??(ye)可??(ke)能?(neng)因??(yin)“經??(jing)驗??(yan)不??(bu)足?(zu)”而??(er)反??(fan)應??(ying)過??(guo)度??(du)??，如??(ru)對??(dui)花??(hua)粉??(fen)、食??(shi)物??(wu)等??(deng)無??(wu)害??(hai)物??(wu)質??(zhi)過??(guo)度?(du)反??(fan)應??(ying)??，引??(yin)發(fā)??(fa)哮??(xiao)喘??(chuan)、濕??(shi)疹??(zhen)；如??(ru)接??(jie)觸??(chu)外??(wai)界??(jie)增??(zeng)多??(duo)??，易??(yi)感??(gan)染??(ran)手??(shou)足??(zu)口??(kou)病??(bing)、水??(shui)痘??(dou)等??(deng)傳??(chuan)染??(ran)病??(bing)???！　∠??(xian)天??(tian)性??(xing)免??(mian)疫??(yi)是??(shi)人??(ren)類??(lei)與??(yu)生??(sheng)俱??(ju)來??(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??(shi)迅??(xun)速??(su)反??(fan)應??(ying)??。??。