11.A new study suggests that early exposure to germs(細菌) strengthens the immune(免疫的)system.That means letting children get a little dirty might be good for their health later in life.
The study involved laboratory mice.It found that adult mice raised in a germ-free environment were more likely to develop allergies.a(chǎn)sthma and other autoimmune disorders. There are more than eighty disorders where cells that normally defend the body instead attack tissues and organs.
Richard Blumberg,who led the study,is a professor at'Harvard Medical School in Boston,Massachusetts.He says,in 1989,medical researchers who sought to explain these diseases,first discovered that the increasing use of antibacterial soaps and other products,especially early in life,could weaken immune systems.
Now,Dr.Blumberg and his team have what is the first biological evidence to link early exposure to germs to stronger adult immune systems.They say this exposure could prevent the development of some autoimmune diseases.
In the adult germ-free mice,they found that inflammation(發(fā)炎)in the lungs and colon was caused by so-called killer T cells.These normally fight infection.But they became overactive and targeted healthy tissue-an autoimmune condition seen in asthma and a disease called ulcerative colitis.
Dr,Blumberg says the mice raised in a normal environment did not have the same reaction.He says their immune systems had been"educated"by early exposure to germs.
Rates of autoimmune disorders are rising worldwide,but mostly in wealthier,industrialized countries.According to Dr.Blumberg,it might be high time that people were warned to be more careful with the early use of antibiotics(抗生素) and the prescription from their doctors.
Rob Dunn is a professor of ecology and evolutionary biology at North Carolina State University in Raleigh.He says the new study does not mean people should stop washing."Wash your hands,but don't do it with antibacterial soap.Let your kids play in a reasonable amount of dirt and get outside and get exposed to a diversity of things",says Rob Dunn.
71.Who first found immune systems might get harmed by overly using antibacterial products?C
A.A professor of ecology and evolutionary biology.
B.A professor at Harvard Medical School in Boston.
C.Medical researchers who tried to explain autoimmune disorders.
D.Medical researchers who tried to treat autoimmune disorders.
72.To keep healthy in the future,children had betterA.
A.play in a dirty environment once in a while
B.live in a germ-free endronrnent
C.use plenty of antibacterial soaps
D.stay in under developed countries
73.Why are germ-free mice easy to develop lung inflanunation?B
A.Because their T celh fight bacteria effectively.
B.Because their T cells attack the healthy tissues.
C.Because their lungs become abnormally active.
D.Because their lungs have weaker tissues.
74.It can be inferred from the text thatD.
A.washing hands is no longer a good habit for children
B.a(chǎn)ntibiotics will be forbidden in children's hospitals
C.exposure to dirt helps build children's character
D.the abuse of antibiotics may be condemned
75.Where does this text most probably come from?C
A.A teacher's handbook. B.A story book.
C.A science magazine. D.A travel journal.
分析 本文屬于說明文閱讀,作者通過這篇文章主要向我們描述了研究發(fā)現(xiàn)免疫系統(tǒng)可能會受到過度使用抗菌產(chǎn)品的傷害,孩子們在一個無菌環(huán)境中成長不利于他們的健康.
解答 71.C.細節(jié)理解題.根據(jù)文章第三段"He says,in 1989,medical researchers who sought to explain these diseases,first discovered that the increasing use of antibacterial soaps and other products,especially early in life,could weaken immune systems"可知試圖解釋自身免疫性疾病的醫(yī)學(xué)研究者首先發(fā)現(xiàn)免疫系統(tǒng)可能會受到過度使用抗菌產(chǎn)品的傷害;故選C.
72.A.細節(jié)理解題.根據(jù)文章最后一段"Let your kids play in a reasonable amount of dirt and get outside and get exposed to a diversity of things"可知為了將來保持健康,孩子們最好偶爾在一個骯臟的環(huán)境;故選A.
73.B.細節(jié)理解題.根據(jù)文章第五段"In the adult germ-free mice,they found that inflammation(發(fā)炎)in the lungs and colon was caused by so-called killer T cells"可知無菌小鼠肺部炎癥容易發(fā)炎是他們的T細胞攻擊健康組織引起;故選B.
74.D.推理判斷題.根據(jù)倒數(shù)第二段"it might be high time that people were warned to be more careful with the early use of antibiotics(抗生素) and the prescription from their doctors"可知濫用抗生素可能會被譴責;故選D.
75.C.主旨大意題.通讀全文,可知文章主要講了研究發(fā)現(xiàn)免疫系統(tǒng)可能會受到過度使用抗菌產(chǎn)品的傷害,孩子們在一個無菌環(huán)境中成長不利于他們的健康;因此文章應(yīng)該出資科學(xué)雜志;故選C.
點評 考察學(xué)生的細節(jié)理解和推理判斷能力,做細節(jié)理解題時一定要找到文章中的原句,和題干進行比較,再做出正確的選擇.在做推理判斷題不要以個人的主觀想象代替文章的事實,要根據(jù)文章事實進行合乎邏輯的推理判斷.