首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Sunlight is a great source of vitamin D in most of the world. Yet a(an)【C1】______number of experts think that many people aren’t
Sunlight is a great source of vitamin D in most of the world. Yet a(an)【C1】______number of experts think that many people aren’t
admin
2012-08-10
75
问题
Sunlight is a great source of vitamin D in most of the world. Yet a(an)【C1】______number of experts think that many people aren’t getting enough vitamin D—【C2】______those who work and play indoors.
It’s long been known that vitamin D is【C3】______for strong bones. Research in the last several years has shown that low levels of vitamin D may increase the risk of heart【C4】______in men and deaths from some cancers. But new research suggests that it also protects against a wide【C5】______of diseases. Low levels of vitamin D have also been【C6】______with various forms of cancer and high blood pressure, stroke,【C7】______illness etc. The strongest source,【C8】______far, is ultraviolet (紫外线) B rays from the sun, which【C9】______a form of cholesterol (胆固醇) into vitamin D in the skin. But UVB rays【C10】______greatly depending on cloud cover, time of year and time of day. Dark-skinned and elderly people don’t【C11】______vitamin D from the sun as【C12】______as younger, fair-skinned people. UVB rays also don’t【C13】______glass or sunscreen with a factor of 8 or more. It’s difficult to get much vitamin D through diet. Few foods【C14】______it naturally. It’s widely【C15】______that most people need some supplemental vitamin D—the question is, how much? Current U. S. guidelines, issued in 1997,【C16】______for 200 international units from birth through age 50. The National Osteoporosis Foundation【C17】______adults over age50 to get at least 800 to 1, 000 IUs to【C18】______against fractures (骨折).
But as some experts research carry【C19】______the experiment, they worry that if people take too much vitamin D, it might act as a poison. Also, skin doctors warn people to be careful with sun【C20】______because of the risk of skin cancer.
【C20】
选项
A、appearance
B、exposure
C、exhibition
D、revelation
答案
B
解析
名词辨义题。本句意为“同时,皮肤科医生告诫人们要小心阳光的直射,因为会有患皮肤癌的危险”,sun exposure“日照”,exposure“暴露”符合题意。appearance“外貌,外观”;exhibition“展览”;revelation“揭露,暴露”,均不符合文意,故排除。
转载请注明原文地址:https://kaotiyun.com/show/ZR57777K
0
大学英语四级
相关试题推荐
Theworkplaceforolderadultsisbecomingadynamicspaceratherthanaunidirectionaljourneyleadingtoretirement.Thenewo
Lookingbackonmychildhood,Iamconvincedthatnaturalistsarebornandnotmade.Althoughwewereallbroughtupinthesam
HowtoMakeaGoodImpressionResearchshowsthatwestarttomakeupourmindsaboutpeoplewithinsevensecondsofmeeting
HowtoMakeaGoodImpressionResearchshowsthatwestarttomakeupourmindsaboutpeoplewithinsevensecondsofmeeting
Theentertainmentprofession,orshowbusiness,attractsmanyyoungpeople.【B1】______,onlyveryfewcanhopetobecomefamousa
A、Threetypesofnoisethatcanmakecommunicationdifficult.B、Themeaningofexternalnoise.C、Theeffectofcigarettesmoke.
ThecauseofthedeclineofNorthAfricaispopularlyattributedtoclimaticchanges,thetheorybeingthattheareabecamehott
Childrenlearnalmostnothingfromtelevision,andthemoretheywatchthelesstheyremember.Theyregardtelevisionpurely【C1】
SigmundFreud,theworld-famousdoctorofVienna,wasathinkerwhochangedthewaywelookatmentaltrouble.Healsohada【S1】
Astudyofarthistorymightbeagoodwaytolearnmoreaboutaculturethanispossibletolearningeneralhistoryclasses.M
随机试题
给选择区添加前景色使用_______组合键。
A、细胞内液B、细胞外液C、细胞外液和细胞内液D、组织液E血浆红细胞的内环境是指
患者,男。40岁,3年前确诊为慢粒白血病。近半月持续高热、脾Ⅲ度肿大。血常规检查:Hb60g/L,WBC25×109/L,PLT55×109/L。骨髓检查:原粒细胞占45%,早幼粒8%。该患者的首选治疗是
临产时子宫下段长约
结石声影与肠气声影的区别在于
()设备最重要的维护工作是构建和维护MAC地址表。
若有以下程序#includemain(){inti,j=0;chara[]="Howareyou!",b[10];for(i=0;a[i];i++)if(a[i]=’’)b[j++]=a[
Theapplicationsfortheopeningpositionneedtobereviewed______theendoftheweek.
Thefridgeisconsideredanecessity.Ithasbeensosincethe1960swhenpackagedfoodfirstappearedwiththelabel:"storein
A.serveB.sponsoredC.profitsD.principlesE.developingF.understandG.billsH.representativeI.submittedJ.govern
最新回复
(
0
)