(Associated Press) -- Blood clots like the one that Secretary of State Hillary Rodham Clinton is being treated for following her recent concussion can occur for a host of reasons. How serious a clot is depends on where it is and why it formed. A Clinton aide would not say where hers is located.

MONTCLAIR, N.J. (Associated Press) -- During stressful times as a combat medic in Afghanistan, Mason Sullivan found solace in Vivaldi. New Jersey native Nairobi Cruz was comforted by country music, a genre she had never heard before joining the Army. For Jose Mercedes, it was an eclectic iPod mix that helped him cope with losing an arm during a tour of duty in Iraq.

LAHORE, Pakistan (AP) -- Under police guard, thousands of health workers pressed on with a polio immunization program Thursday after nine were killed elsewhere in Pakistan by suspected militants who oppose the vaccination campaign.

LONDON (AP) -- Rock 'n' roll will never die -- but it's a hazardous occupation.

(USA TODAY) -- The nation's most elite fighting forces -- celebrated this year in film and best-selling books -- are under more emotional strain after a decade of war than commanders realized, according to the senior non-commissioned officer for special operations.

PESHAWAR, Pakistan (Canadian Press) -- The United Nations suspended its polio vaccination drive in Pakistan on Wednesday after eight people involved in the effort were shot dead in the past two days, a U.N. official said.

WASHINGTON (AP) -- They might not want to talk about the gunshots or the screams. But their toys might start getting into imaginary shootouts.

WASHINGTON (AP) -- Your medical plan is facing an unexpected expense, so you probably are, too. It's a new, $63-per-head fee to cushion the cost of covering people with pre-existing conditions under President Barack Obama's health care overhaul.

WASHINGTON (AP) -- Native American military veterans will be able to access health care closer to home thanks to an agreement between the U.S. Department of Veteran Affairs and the Indian Health Service.

WASHINGTON (Deutsche Presse-Agentur (dpa)) -- A new study suggests that mild but repeated brain injuries often sustained by athletes can lead to degenerative brain disease in the long run.

NEW YORK (AP) -- Flu season in the U.S. is off to its earliest start in nearly a decade -- and it could be a bad one.