首页
登录
职称英语
For years the media, food labels, dietitians, and even scientists who should
For years the media, food labels, dietitians, and even scientists who should
游客
2023-09-01
74
管理
问题
For years the media, food labels, dietitians, and even scientists who should know better have bombarded (轰炸) us with advice to load up on antioxidants: compounds found mostly in fruits and vegetables that mop up free radicals, which are highly reactive clusters of atoms that have been fingered as the evil-doers responsible for aging and for illnesses from cancer to heart disease.
Not so fast. First, studies piled up showing that taking antioxidants—even such common and seemingly harmless ones as vitamins C and E—as supplements was not beneficial to health and might even be dangerous. Many of the free radicals that are neutralized by antioxidants perform valuable functions in the body. The most important:fighting toxins (毒素) and fighting cancer. Maybe it’s not such an excellent idea to flood the body with something that neutralizes these warriors of the immune system. Or as British chemist and science writer David Bradley noted in his blog,Reactive Reports,"It’s always struck: me as odd that you would want to absorb extra antioxidants anyway, given that oxidizing agents are at the front-line of immune defense against pathogens (病原体) and cancer cells...Suffice to say that taking antioxidant supplements... may not necessarily be good for your health if you already have health problems, especially cancer or an infection. "
The first hints that the trend was crashing came from the hundreds of studies that have tried to assess the health effects of antioxidant supplements. The results have not been pretty. In 2008 the Cochrane Collaboration, an international organization of scientists who assess medical research, carefully checked 67 studies with nearly 400,000 participants. The goal;to determine whether antioxidant supplements reduce mortality in either healthy people or in people with diseases. Conclusion:" We found no evidence to support antioxidant supplements for primary or secondary prevention, and Vitamin A and E may increase mortality. " In analyses of antioxidant supplements and Lou Gehrig’s disease, Alzheimer’s or mild cognitive impairment, and lung cancer, the Cochrane scientists’ verdict was the same: no. And each analysis had an alarming refrain about increasing overall mortality.
It’s not clear why antioxidants in supplement form might be so dangerous. One idea holds that at high doses they become pro-oxidants,stimulating the harmful DNA- and cell-damaging reactions they’re supposed to prevent. But a more likely explanation is that we are seeing the human version of what scientists are finding in studies of lab animals: antioxidants interfere with immune-system cells that fight infection and cancer. [br] The most important function of some free radicals neutralized by antioxidants is______.
选项
A、loading up on antioxidants
B、fighting toxins and cancer cells
C、protecting pathogens and DNA
D、absorbing antioxidant supplements
答案
B
解析
事实细节题。定位句指出,很多被抗氧化物中和的自由基在人体中有着非常重要的功能,最重要的功能就是用来清除毒素和癌细胞,即有些自由基的最重要功能是清除毒素和癌细胞。因此,B)符合题意,故为本题答案。A)“补充足量抗氧化物”和D)“吸收抗氧化物补充物”明显错误,故排除;C)“保护病原体和DNA”,不符合原文,故排除。
转载请注明原文地址:https://tihaiku.com/zcyy/2976078.html
相关试题推荐
Wehavegottheorder______(房屋在什么时候以什么样的方式拆毁).whenandhowthehouseshouldb
He______(不应该让我们等了那么长时间)fornoreasonatall,whichisquiteimpolite.shouldn’
[audioFiles]audio_eusm_j01_190(20099)[/audioFiles]A、Sheshouldliveinthecoun
[originaltext]Why,youmaywonder,shouldspidersbeourfriends?(26)Beca
[originaltext]Why,youmaywonder,shouldspidersbeourfriends?(26)Beca
[originaltext]Why,youmaywonder,shouldspidersbeourfriends?(26)Beca
Scientistswillhaveto_______________________________(提出增加世界粮食供应量的新方法).comeup
[originaltext]Asisknowntoall,scientistsandphilosophershadstudiedt
[originaltext]Asisknowntoall,scientistsandphilosophershadstudiedt
[originaltext]Asisknowntoall,scientistsandphilosophershadstudiedt
随机试题
WhereistheWestEnd?A、InVancouver.B、InNewYork.C、InSydney.D、InLondon.
在进行钢筋焊接接头的拉伸试验时,如果试件断于热影响区,但呈延性断裂,则应视作与断
(共用题干)患者男,53岁。因肝硬化抽腹水,2h后出现意识障碍,精神恍惚,有错觉
某城镇拟修建一座小型水库为居民供水,某测绘单位承接了该工程的测绘任务。 1
最易诱发急性粟粒型肺结核的是A.麻疹 B.百日咳 C.猩红热 D.营养不良
子宫颈炎最为常见的病理改变是A:宫颈糜烂 B:宫颈息肉 C:宫颈内膜炎 D
变电运维管理中国网公司负责组织并提出()类变电站工作要求一$;$二$;$三$;$
0,4,16,48,128,() A.280B.320C.350D.
张老师在小学英语教学中恰当运用英语剧的形式教学,让学生在角色扮演中学习英语,张老
根据政府采购法律制度的规定,下列各项中,属于供应商应当具备的条件有()。A
最新回复
(
0
)