SSS 2011-11-07
时间：2019-01-08 作者：英语课 分类：Scientific American(十一)月
英语课
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 permanently 1 damage in DNA 2 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 Proceeding 3 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
adv.永恒地，永久地，固定不变地
- The accident left him permanently scarred.那次事故给他留下了永久的伤疤。
- The ship is now permanently moored on the Thames in London.该船现在永久地停泊在伦敦泰晤士河边。
(缩)deoxyribonucleic acid 脱氧核糖核酸
- DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
- Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。
n.行动，进行，(pl.)会议录，学报
- This train is now proceeding from Paris to London.这次列车从巴黎开往伦敦。
- The work is proceeding briskly.工作很有生气地进展着。