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　　肉??(rou)、蛋??(dan)、奶??(nai)??，這??(zhe)些??(xie)食??(shi)物??(wu)中??(zhong)含??(han)有??(you)豐??(feng)富??(fu)的??(de)蛋??(dan)白??(bai)質(zhì)??(zhi)??，可??(ke)以??(yi)提??(ti)供??(gong)人??(ren)類??(lei)身??(shen)體?(ti)所?(suo)需??(xu)營(yíng)??(ying)養(yǎng)??(yang)??。??但??(dan)天??(tian)然??(ran)的??(de)蛋??(dan)白??(bai)質(zhì)??(zhi)難?(nan)以??(yi)發(fā)??(fa)揮??(hui)這??(zhe)些??(xie)功??(gong)能??(neng)??，科??(ke)研??(yan)人??(ren)員??(yuan)需??(xu)要??(yao)對(duì)??(dui)天??(tian)然??(ran)蛋??(dan)白??(bai)質(zhì)??(zhi)的??(de)功??(gong)能??(neng)進(jìn)??(jin)行??(xing)設(shè)??(she)計(jì)??(ji)和??(he)改??(gai)造??(zao)??，才??(cai)能??(neng)使?(shi)它??(ta)成??(cheng)為??(wei)滿??(man)足??(zu)應(yīng)??(ying)用??(yong)需?(xu)求?(qiu)的??(de)產(chǎn)??(chan)品??(pin)??。長(zhǎng)??(chang)期??(qi)以??(yi)來(lái)??(lai)??，蛋??(dan)白??(bai)質(zhì)??(zhi)設(shè)??(she)計(jì)??(ji)改??(gai)造??(zao)一??(yi)直??(zhi)面??(mian)臨??(lin)時(shí)?(shi)間??(jian)長(zhǎng)?(chang)、成??(cheng)本??(ben)高??(gao)等?(deng)難?(nan)題??(ti)??。。