Researchers at the Brookhaven National Laboratory in Upton, New York, reported that something in cigarette smoke lowers the levels of an enzyme known as MAO B.

• 纽约厄普顿的布鲁克黑文国家实验室的研究人员报告说:卷烟烟雾中的某种物质减少了一种酶--也就是人们所知的单胺氧化酶b的含量。