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This year's flu vaccine protects against a few different virus strains, including the H1N1 seen here. The fuzzy outer layer is made of proteins that allow the virus to attach to human cells. NIAID/Flickr hide caption

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The Alto Yellowjackets take the field on Nov. 13, a month after Matthews died. Lauren Silverman/NPR hide caption

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If you cook meat too long, at too high a temperature, the chemical reaction that creates tasty flavor and aroma compounds keeps going, creating other compounds. Some of those compounds can be carcinogenic when we consume them in high-enough concentrations. Morgan McCloy/NPR hide caption

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Addiction counselor John Fisher says prescriptions for medicines to help people wean themselves from opioid drugs are part of the appeal of the clinic he operates in Blountville, Tenn. Blake Farmer/NPR hide caption

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Gretchen Burns-Bergman (center) speaks Wednesday at a rally in front of the White House about ending mass incarceration of drug users. Angus Chen/NPR hide caption

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Breast cancer drug Herceptin is one of the medicines that are typically covered by insurers but often at a high out-of-pocket cost for patients. Jeff J Mitchell/Getty Images hide caption

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