A cross-section of skeletal muscle in this light micrograph shows the individual, parallel muscle fibers (red). These fibers work in concert to power movement. Thomas Deerinck, NCMIR/ScienceSource hide caption

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Experimental Technique Coaxes Muscles Destroyed By War To Regrow
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Oklahoma Gov. Mary Fallin issues a statement to the media after the execution of Clayton Lockett. Oklahoma Secretary of Safety and Security Michael C. Thompson stands behind her at the Oklahoma State Capitol in Oklahoma City. Alonzo Adams/AP hide caption

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Testosterone levels in men can go up and down throughout the day. Katherine Streeter for NPR hide caption

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Test First Before Going For Those Testosterone Supplements
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Testosterone, The Biggest Men's Health Craze Since Viagra, May Be Risky
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Fear Of Addiction Means Chronic Pain Goes Untreated
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False-color transmission electron micrograph of a field of whooping cough bacteria, Bordetella pertussis. A. Barry Dowsett/Science Source hide caption

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Family Tree Of Pertussis Traced, Could Lead To Better Vaccine
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There today, here tomorrow: A mother holds her child for a measles vaccination in Manila, Philippines, in January. Travelers are bringing measles from the Philippines to the United States. Noel Celis/AFP/Getty Images hide caption

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Blockbuster Trades Are Changing The Face Of Pharmaceuticals
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How Hospitals Can Reduce Disabilities For Stroke Patients
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