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" Cell therapy " ( also called " cellular therapy , cell transplantation , " or " cytotherapy " ) is a therapy in which viable cells are injected , grafted or implanted into a patient in order to effectuate a medicinal effect , In 1931 Paul Niehans ( 1882 – 1971 ) " & ndash ; who has been called the inventor of cell therapy " & ndash ; attempted to cure a patient by injecting material from calf embryos .
 person: Paul Niehans
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Answer:
 person: Paul Niehans