Each of these mouse pups was born from an egg scientists created using embryonic stem cells. It's possible the technology could change future treatment for human infertility. Katsuhiko Hayashi hide caption

toggle caption Katsuhiko Hayashi

Sue Freeman, 78, checks her email at her home in Laguna Beach, Calif., on Saturday. She says her eyesight improved markedly since she received an experimental stem-cell procedure last July. Melissa Forsyth for NPR hide caption

toggle caption Melissa Forsyth for NPR

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