A virus called XMRV was linked to chronic fatigue syndrome in a study published in Science in 2009. Now that paper has been withdrawn. David Schumick and Joseph Pangrace/Cleveland Clinic Center for Medical Art & Photography hide caption

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Often times, bed bug infestations stem from a succession of inbreeding from one female's progeny. Orkin, LLC/PR NEWSWIRE hide caption

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H5N1 avian flu viruses (seen in gold) grow inside canine kidney cells (seen in green). Cynthia Goldsmith/CDC hide caption

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One recent study found that people were able to burn up an extra 450 calories a day with one hour of moderate exercise. That can include walking briskly, biking or swimming.

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Brain researchers say the big fluctuations in IQ performance they found in teens were not random — or a fluke.

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Even with a strong maternal relationship, teenage boys who watch a lot of TV acquire their attitudes toward sex from gender stereotypes seen on the tube, a new study says.

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Victims of the plague are consigned to a communal burial during the Plague of London in 1665.

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