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Fact and Fancy is a collection of seventeen scientific essays by Isaac Asimov. It was the first in a series of books collecting his essays from The Magazine of Fantasy and Science Fiction, and Asimov's second book of science essays altogether. Doubleday & Company first published it in March 1962. It was also …
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Four men and a woman are reduced to a microscopic fraction of their original size, sent in a miniaturized atomic sub through a dying man's carotid artery to destroy a blood clot in his brain. If they fail, the entire world will be doomed.
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Fantastic Voyage II: Destination Brain is a 1987 science fiction novel by Isaac Asimov about a group of scientists that shrink to microscopic size in order to enter a human brain so that they can retrieve memories from a comatose colleague.