American researchers say drinking tea may help strengthen the body’s defense system against infection(感染).Doctors at Brigham and Women’s Hospital in Boston,Massachusetts,did the study.The team studied a chemical found in black,green,oolong and pekoe tea This chemical is an amino acid(氨基酸)called L-theanine.The scientists say it may increase the strength of Gamma delta T cells,which are part of the body’s defenses.

First,the researchers mixed some of these cells with antigens(抗原)found in the amino acid Antigens help the body react to infection.Then the scientists added some bacteria(細菌).

Within twenty-four hours,the cells produced a lot of interferon,a substance that fights infection Cells not mixed with the antigens did not produce interferon.

In the second part of the study,eleven people drank five to six cups of black tea every day.Ten other people drank the same amount of instant coffee.That is dried coffee mixed with hot water.

Two weeks later,and again two weeks after that,the researchers tested the blood of all twenty-one people.They also looked at what happened when they added bacteria to the blood cells.They found that the tea drinkers produced five times more interferon after they started drinking tea The coffee drinkers did not produce interferon.

Doctor Jack Bukowski led the study He says the antigens added to the Gamma delta T cells were responsible for the increased reaction to the bacteria.He says the study also showed that the cells were able to remember the bacteria and fight them again the next time.

Earlier research already has found that tea can help prevent heart disease and cancer Doctor Bukowski says the new study must be repeated with more people.If the findings prove to be true,he says,then tea drinking might also help protect against bacterial infections.He says the amino acid L-theanine could be removed from tea and used as a drug to strengthen the body’s defenses.

73.We may know from the text that     can be found in different kinds of tea.

A.Gamma delta T cells                                B.L-theanine

C.interferon                                        D.bacteria

74.Tea may help strengthen the body’s defense system because it helps     .

A.the body to produce more interferon

B.the body to produce more Gamma delta T cells

C.to add some bacteria to the blood cells

D.to mix antigens with some of the cells in the body

75.According to Dr Bukowski,     .

A.the findings of the study have already proved to be true

B.he bas taken some amino acid L-theanine from tea and made a drug with it

C.further study is needed to prove the findings true

D.he is not sure whether tea can help prevent heart disease and cancer

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Dear Christie,

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閱讀下面短文,從短文所給各題的四個選項(A、B、C、D)中選出能填入相應(yīng)空白處的最佳選項。

   Newcomers(新來的人) to the United States are often    36    by the schools. American schools    37    seem so different from the schools they know in    38    parts of the world. American education is based on the    39    that children    40    to learn to think    41    themselves. The school should be the    42    where they learn to do this.    43   , children learn the “three R’s” [(Reading, Writing and Arithmetic(算術(shù))], history and government (often called Social Studies) and many other    44   . They also learn    45   be independent(獨立的),how to make their own judgement(判斷), and how to develop their own   46    and interests. The American teacher does not    47   the children in her class to sit    48   hands folded quietly and to say    49  . She wants them to listen attentively(專心地) to ask questions. She knows that    50    children learn from books is    51  . She also knows that it is necessary for them to know how to use this    52   for their   53    and development. During Open School Week, parents have a    54    to see how American education    55   .

【小題1】A. happy          B. afraid               C. glad             D. surprised

【小題1】 A. some time    B. sometime         C. sometimes            D. some times

【小題1】A. other          B. the other            C. another              D. all

【小題1】 A. opinion      B. idea                 C. promise          D. conclusion

【小題1】A. need           B. needed               C. dare                 D. dared

【小題1】A. of             B. against          C. for                  D. with

【小題1】 A. place         B. space            C. room             D. area

【小題1】A. From school    B. out school           C. By school            D. In school

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【小題1】A. ability        B. skill                C. abilities            D. skills

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【小題1】A. something      B. anything             C. nothing              D. much

【小題1】A. that          B. which            C. where                D. what

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【小題1】A. ability            B. possibility          C. interest             D. chance

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