How does the doctor decide what to write on the prescription pad? iStockphoto.com hide caption

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Soda bottles and household chemicals are sometimes used to make low-power bombs. iStockphoto.com hide caption

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Two women in Colombo, Sri Lanka, attend a March protest calling for government action against domestic violence and rape. Dinuka Liyanawatte/Reuters /Landov hide caption

itoggle caption Dinuka Liyanawatte/Reuters /Landov

Bad bug: The bacterium Clostridium difficile kills 14,000 people in the United States each year. Janice Carr/CDC/dapd hide caption

itoggle caption Janice Carr/CDC/dapd

The newest version of the Robohand is made of snap-together parts, reducing the amount of hardware needed. Courtesy of Jen Owen of Jen Martin Studios hide caption

itoggle caption Courtesy of Jen Owen of Jen Martin Studios

Chimpanzee Toni celebrated his 50th birthday at the Hellabrunn Zoo in Munich on Nov. 22, 2011. Sven Hoppe/DPA/Landov hide caption

itoggle caption Sven Hoppe/DPA/Landov

A woodcut from the 1800s, Healing the Lepers, depicts the common tableau of Jesus healing a leper as his disciples look on. Images from the History of Medicine hide caption

itoggle caption Images from the History of Medicine

Talk therapy is best for some people; antidepressants are better for others. Scientists say PET scans might help figure out early on what treatment a person needs. iStockphoto.com hide caption

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