- 1、本文档共23页,可阅读全部内容。
- 2、原创力文档(book118)网站文档一经付费(服务费),不意味着购买了该文档的版权,仅供个人/单位学习、研究之用,不得用于商业用途,未经授权,严禁复制、发行、汇编、翻译或者网络传播等,侵权必究。
- 3、本站所有内容均由合作方或网友上传,本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺!文档内容仅供研究参考,付费前请自行鉴别。如您付费,意味着您自己接受本站规则且自行承担风险,本站不退款、不进行额外附加服务;查看《如何避免下载的几个坑》。如果您已付费下载过本站文档,您可以点击 这里二次下载。
- 4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等,请点击“版权申诉”(推荐),也可以打举报电话:400-050-0827(电话支持时间:9:00-18:30)。
1.阅读理解
ScientistsmayhavefoundawaytoreduceshortageoftypeOblood.TypeOisthe
kindofbloodthathospitalsmostoftenneed.Whattheresearchersaretestingisaneasier
waytomaketypeObloodoutofotherkindsofblood.
Therearefourmainkindsofblood.Mostpeoplebornwithoneofthesefour:Type,
TypeB,TypeBorTypeO.TypeOcanbesafelygiventoanyone.Soitiscommonly
usedwhenapersonisinjuredorsickandhastohaveblood.
TypeOisthemostcommonbloodgroup.Butthesuppliesofitavailableinhospitals
andbloodbanksareusuallylimited.Thisisbecauseofthehighdemandforit.TypeO
bloodisusedinemergencieswhenthereisnotimetoidentifythepatientsbloodtype.
Giving,BorBtosomeonewithadifferentbloodtype,includingO,cancausea
badreactionbythepersonsdefensesystem.Theirimmunesystemcanrejecttheblood.
Thisimmunereactioncanbedeadly.
Thedifferencesamongbloodtypesarelinkedtowhetherornotredbloodcells
containcertainkindsofsugarmolecules.Thesemoleculesarefoundonthesurfaceofthe
cells.Theyareknownasantigens(抗原).Theseantigensarefoundwithtype,Band
BbloodbutnotwithtypeO.
Morethantwenty-fiveyearsago,scientistsfoundthattheantigenscouldberemoved
tocreatewhattheycalleduniversal-typecells.Theycouldberemovedwithchemicals
calledenzymes(酶).Butlargeamountsofenzymeswererequiredtomakethechange.
DoctorHenrikClausenoftheUniversityofCopenhageninDenmarkledthestudy.
Thenextstep,hesays,istocompletesafetytests.Theteamisworkingwiththemerican
companyZymeQuesttotestthenewmethod.Ifitmeetssafetyrequirements(要求)and
isnottoocostly,itcouldbecomeawidelyusedlife-savingtooltoincreasethesupplyof
universalblood.
1.(1)HowdoscientistsdealwiththeproblemoflackingtypeOblood?
.Developnew
您可能关注的文档
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070404.pdf
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070405.pdf
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070415.pdf
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070421.pdf
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070441.pdf
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070449.pdf
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070451.pdf
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070452.pdf
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070516.pdf
- 2023-2024学年全国全部高中英语同步练习共14题(含答案解析)2024-06-15 070536.pdf
文档评论(0)