Questions 38-41 Complete the sentences below. Choose your answers from the list of words. You can only use each word once. NB There are more words in the list than spaces so you will not use them all. In the first clinical trials, scientists will try to 38___________ adenovirus and vaccinia, so both the viruses will be less pathogenic than the 39___________ These uncoated viruses will be applied directly to certain areas to confirm safety on human beings and the right 40___________ needed. The experiments will firstly be 41___________ to the treatment of certain cancers List of Words dosage responding smallpox virus disable natural ones inject directed treatment cold-like illness kill patients examined
38.___________
39.___________
40.___________
41.___________
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A.___________
39.___________
40.___________
41.___________