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原標(biāo)題：20岁1069gay男同志

　　免??(mian)疫?(yi)系?(xi)統(tǒng)??(tong)的?(de)核??(he)心??(xin)使??(shi)命??(ming)不??(bu)是??(shi)“消??(xiao)滅??(mie)一?(yi)切??(qie)”??，而??(er)是??(shi)識??(shi)別??(bie)敵??(di)我??(wo)、清??(qing)除??(chu)威??(wei)脅??(xie)??。??　　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(yīng)??(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(chǎn)??(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(jīng)??(jing)驗??(yan)不??(bu)足??(zu)”而??(er)反??(fan)應(yīng)??(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(zhì)??(zhi)過??(guo)度??(du)反??(fan)應(yīng)??(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)??。。