cigarette couple smoking hi-res stock photography and images A young man lights a

STD transmission through saliva alone is relatively uncommon

But those who are of a tangier persuasion might not be as happy

A critical role for DNA end-joining proteins in both lymphogenesis and neurogenesis

Aerosol is a gas mixed with particles, Choi said

Wider use "For some people, with normal metabolism of nicotine, the chance of success might be low on the patches but could double if they take the pill while for a third of the population with slower breakdown, cheaper patches might be best." Blood tests to check for nicotine breakdown speed are currently used in research but scientists say they could be easily developed for much wider use