问题
单项选择题
《人畜共患传染病名录》中不包括()
A.炭疽杆菌
B.狂犬病
C.猪乙型脑炎
D.猪弓形虫
E.高致病性猪蓝耳病
答案
参考答案:E
《人畜共患传染病名录》中不包括()
A.炭疽杆菌
B.狂犬病
C.猪乙型脑炎
D.猪弓形虫
E.高致病性猪蓝耳病
参考答案:E
Five cloned pigs,whose organs are much less likely to be rejected(排斥) by a patient,have been born in the U.S. More than 62,000 people in the U.S. alone are waiting to ____ donated hearts,lungs and so on.The number of human donors falls far short of ____.Pig organs are of a(n) ____ size to human organs,and some scientists hope they might be used to help meet the ____.But previous attempts to transplant pig tissue into humans have ____. The five pigs ____ a gene that adds a sugar to the surface of pig cells.The sugar would ____ immune(免疫的) rejection of the tissue.“This advance provides a neartime ____ for overcoming the problem that there is not enough human organs for transplants,”says an expert.“This is the ____ gene for overcoming the ____ stage of rejection.” ____,scientists warn that much more work is necessary ____ organs from copies of the pigs could be transplanted into humans.Human genes will need to be added,to ____ rejection of the organ in the long term.There are also ____ that pig viruses could infect patients. Cloning techniques were ____ to the production of the pigs.Genes can only be knocked out(去除) in a single cell.Cloning of these single cells then allowed the ____ of a whole animal in which the gene was knocked out in every cell.But the PPL researchers have ____ in knocking out only one copy of the gene.The team will now attempt to knock out both copies of the gene. The team will also ____ tests to investigate whether a virus from the pigs could infect human cells.“Although a lot of the work is very ____,we’re still very far off being able to grow an organ,” says Julia,who is working on this project and quite ____ to creating similar knockout pigs with researchers at the University of Missouri.
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