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"Launching radioactive material through the Earth's atmosphere brings safety concerns. You have to have a special license to do that, but it is not insurmountable," says Dr Simeon Barber, planetary science specialist at the Open University.
，这一点在同城约会中也有详细论述
He said it was likely hospitals would start using surgeons and theatres more to carry out operations that do not require bone cement.
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