北京时间4月27日16时24分，经过近16个小时的飞行，运送旅美大熊猫“丫丫”的货运专机在上海浦东机场降落。在中方兽医和工作人员的陪护下，前往封闭隔离检疫区。

xinzhongguochenglizhichu，shiyingdangshidejihuajingjitizhi，zhongguozaichengshijianlileyouqiyefuzejiaofeidexianshouxianfudechengzhenzhigongtuixiuzhidu，zainongcunjianlileshiyingrenmingongshetizhidechuantongjiatingyanglaozhiduhewuzinvde“wubaohu”zhidu。新(xin)中(zhong)国(guo)成(cheng)立(li)之(zhi)初(chu)，(，)适(shi)应(ying)当(dang)时(shi)的(de)计(ji)划(hua)经(jing)济(ji)体(ti)制(zhi)，(，)中(zhong)国(guo)在(zai)城(cheng)市(shi)建(jian)立(li)了(le)由(you)企(qi)业(ye)负(fu)责(ze)缴(jiao)费(fei)的(de)现(xian)收(shou)现(xian)付(fu)的(de)城(cheng)镇(zhen)职(zhi)工(gong)退(tui)休(xiu)制(zhi)度(du)，(，)在(zai)农(nong)村(cun)建(jian)立(li)了(le)适(shi)应(ying)人(ren)民(min)公(gong)社(she)体(ti)制(zhi)的(de)传(chuan)统(tong)家(jia)庭(ting)养(yang)老(lao)制(zhi)度(du)和(he)无(wu)子(zi)女(nv)的(de)“(“)五(wu)保(bao)户(hu)”(”)制(zhi)度(du)。(。)