CHICAGO (Reuters) - U.S. researchers may have found an obesity treatment that unlocks the fat-fighting promise of leptin, an appetite-suppressing hormone once hailed as the answer to the battle of the bulge.

WASHINGTON (Reuters) - A dangerous type of snoring known as sleep apnea can cause stroke by decreasing blood flow, raising blood pressure and harming the brain's ability to modulate these changes, researchers reported on Tuesday.

WASHINGTON (Reuters) - U.S. health officials proposed paying for wider use of PET scans to help doctors decide the initial course of treatment in some cancer patients, the Centers for Medicare & Medicaid Services said on Tuesday.

NEW YORK (Reuters Health) - New research indicates that drinking coffee lowers the risk of developing cancer of the oral cavity or throat, at least in the general population of Japan.

LONDON (Reuters) - Too many children remain unvaccinated against measles for Europe to have any realistic hope of eliminating the disease by 2010, researchers said on Wednesday.

YANJIAO, China (Reuters) - China issued a bird flu alert Wednesday after a woman died of the virus, the first such death in the country in almost a year, and closed poultry markets for disinfecting in a province surrounding Beijing.

WASHINGTON (Reuters) - Deep brain stimulation dramatically improves Parkinson's disease symptoms such as trembling and slowness of movement, offering hope to many with the incurable ailment, researchers said on Tuesday.

CHICAGO (Reuters) - Implantable heart defibrillators -- which have been found to save lives in younger patients -- appear to have the same benefit for people over 70, U.S. researchers said on Tuesday.

NEW YORK (Reuters Health) - Because of long waits, some children who are brought to an emergency room never get treated before they and their caretakers have to leave.

NEW YORK (Reuters Health) - Hepatitis A infections, usually transmitted via contaminated food, can cause debilitating illness, but protection afforded by the hepatitis A vaccine last more than a decade, a new study shows.