科學家的道德疑慮
A group of stem cell scientists has received approval from the Japanese government to create animal embryos containing human cells, with the goal of growing organs in animals that can be used for human transplants.
有一群幹細胞科學家已獲得日本政府批准，能合法創造含有人體細胞的動物胚胎，他們的目標是在動物體內培養用於人體移植的器官。
stem cell 幹細胞approval(n.) 批准、核准、認可=permission=backingorgan(n.)器官transplant(n.)(v.)(由指器官)移植with the goal of~=with the aim of~=with the intention of~目的是...=for the purpose of~
Hiromitsu Nakauchi, who leads teams at the University of Tokyo and Stanford University in California, plans to insert human stem cells into the embryos of rodents and then transplant those embryos into surrogate animals.
率領東京大學和史丹佛大學團隊的教授中內啟光計畫在老鼠胚胎內植入人類幹細胞，接著將胚胎移植到代孕動物體內培育，
insert(v.)(n.)插入surrogate(adj.)代理的;替代的(n.)替代、代理、代理孕母
Nakauchi’s ultimate goal is to develop a human pancreas in animals that could be transplanted into human recipients.
中內的終極目標是在代孕動物體內培養出可移植到人體內的胰臟。
ultimate(adj.)終極的;最後的pancreas(n.)胰臟recipient(n.)接受者;領受者;承受者donor(n.)捐贈者
Japan had previously prohibited the creation and experimentation of animal embryos containing human cells beyond 14 days.
日本過去禁止將含有人類細胞的胚胎培育超過14天，
prohibit(v.)禁止ban-banned-banned禁止forbid-forbade-forbidden禁止
But in March, the country’s education and science ministry issued new guidelines, effectively lifting the 14-day limit on developing embryos and allowing the creation of human–animal chimeras that can be transplanted into surrogate animals.
但在今年3月，日本文部科學省通過新法令，解除培育胚胎不超過14天的限制，允許創造人獸嵌合胚胎，並將其移植到替代動物體內，
chimera(n.)(希臘神話)獅頭、羊身、蛇尾的吐火女怪、虛構的怪物、幻想、妄想、（生物）嵌合體
Nakauchi’s experiment is the first to be approved following the rule change.
中內的實驗是在日本政府解禁後第一個獲得批准的實驗。
following(prep.)在…之後
While the Japanese government gives permission for long-term chimeric organ experiments, some scientists have expressed ethical concerns.
雖然日本已允許進行長期嵌合器官實驗，有些科學家指出了其中的道德疑慮，
give permission for~允許=approvechimeric(adj.)空想的;荒唐的;(生物)嵌合體的ethical(adj.)道德的ethics(n.)倫理學
Their biggest worry is how human cells could affect the cognition of the surrogate animal over time.
他們最擔心的是，長時間下來人類細胞會影響代孕動物的認知，
cognition(n.)認知over time 到時候、漸漸地
They fear the human cells may travel into the animal’s brain, which could lead to unpredictable consequences.
他們害怕人類細胞可能進入動物的大腦，將導致無法預測的後果。
lead to~導致;造成=cause=give rise to~=bring about=result in~