Soldiers participate in physical therapy while using a prosthetic brace called the Intrepid Dynamic Exoskeletal Orthosis (IDEO), which allows them to use and strengthen severely injured legs. John Moore/Getty Images hide caption

itoggle caption John Moore/Getty Images

Mary-Claire King says obscurity gave her the freedom to spend years looking for breast cancer genes. Mary Levin/University of Washington hide caption

itoggle caption Mary Levin/University of Washington

If new guidelines are followed fully, half the medicine chests in America could eventually be stocked with cholesterol-lowering drugs such as atorvastatin, the generic form of Lipitor. Bill Gallery/AP hide caption

itoggle caption Bill Gallery/AP