SSS 2011-11-07

搜索关注在线英语听力室公众号：tingroom，领取免费英语资料大礼包。

The early bird gets the worm, and may avoid skin cancer. Because a new mouse study suggests that for humans, tanning in the mornings may be less likely to permanently¹ damage in DNA² and cause skin cancer. A mouse’s levels of the DNA repair protein XPA are different from ours. They peaked in the morning and bottom out in the evening. Researchers expose mice to UV radiation when their XPA was at their minimum level, around 4 a.m., and other to the same rays around 4 p.m. when XPA levels peaked. Mice who tanned while low on their repair protein develop skin cancer faster and 5 times more frequently than their evening tanning counterparts. The studies in the Proceeding³ of the National Academy of Sciences. Unlike mice, humans are nocturnal, so their XPA level raise and fall at different times. In people, XPA at prime DNA repairing levels in the morning, which does look like the safest time for UV exposure. So if you want to avoid skin cancer, probably go to the tanning’s long early, or better yet, don’t go at all

分享到：