</p> A They may cause some damage to the body cells.$ X: a+ e6 c5 t: |8 y
B They are harmful materials themselves.& e+ Y3 F$ Z2 \! @6 H7 S
C They may store in the body., `" o6 [; d+ H$ \, ?/ c
D They may behave differently in the body and the environment.9 e% ]" [% Q$ y3 G! x; i% A
答案与题解:" T. V; Q% k5 x/ Y4 I* c; T) M' j
1.B 本题选项A在第一段第三句提到,选项C在第二段倒数第二句和第四段第一句提到,选项D则在第四段第二、三、四句提到,只有选项B全文均未提及。
, s& V* s& ~7 _ 2.C 第三段最后两句说到,如果存在靶分子的话,量子点就会发光,以此辨认疾病,这正是本题答案。+ G; H" T2 s6 J. K% j' i' i
3.A 第四段全段都在讲纳米技术如何提高药物疗效,而中心就在于纳米技术能使药物对准疾病病灶(文章中实际是举已经研发的治癌药为例)从而提高药物疗效。1 p. X/ t. d1 Y' u4 G
4.C 第五段第二句已经说得很清楚,其中并没有Iran。+ f* [3 a9 [ m, _2 M
5.D 第五段第三、四句说到,纳米材料的颗粒在体内和在体外环境中作用可能不太一样,因此可能存在某种危险性。其实言外之意还存在未知数,所以后一句才说需要更多投入以便搞清它们的危险性。2 N" B3 i, d* f' b2 T
Multivitamins Urged for All Pregnant Women* Z3 k5 K. h t2 u
A recent study in Tanzania found that when pregnant women took vitamins every day, fewer babies were born too small. Babies that weigh less than two and one-half kilograms at birth have a greater risk of dying. Those that survive are more likely to experience problems with their development. And experts say that as adults they have a higher risk of diseases including heart disease and diabetes. The World Health Organization1 estimates that every year twenty million babies are born with low birth weight. Nine out of ten of them are born in developing countries.
( t* z1 u; P. |$ @( o The new study took place in Dares Salaam. 4, 200 pregnant women received multivitamins. The pills contained all of the vitamins in the B group along with2 vitamins C and E. They also contained several times more iron and folate than the levels advised for women in developed nations. Pregnant women especially in poor countries may find it difficult to get enough vitamins and minerals from the foods in their diet.
' N' d6 ^' ]$ Q4 V9 F The scientists compared the findings with results from a group of 4,000 women who did not receive the vitamins. A report by the scientists, from the United States and Tanzania, appeared in the New England Journal of Medicine. 3 Wafaie Fawzi of the Harvard University School of Public Health4 led the study. None of the women in the study had HIV, the virus that causes AIDS. The scientists reported earlier that daily multivitamins were a low-cost way to reduce fetal deaths in pregnant women infected with5 HIV. The earlier work in Tanzania also found improvement in the mothers in their number of blood cells known as lymphocytes. Lymphocytes increase the body’s immunity against infection.
/ e( F# W- K; i0 h4 s% v The new study in pregnant women who were not infected with the AIDS virus found that multivitamins reduced the risk of low birth weight. Just under eight percent of the babies born to women who took the multivitamins weighed less than 2,500 grams. The rate was almost nine and one-half percent in the group of women who received a placebo, an inactive pill, instead of the vitamins. But the vitamins did not do much to reduce the rates of babies being born too early or dying while still a fetus. Still, the researchers say multivitamins should be considered for all pregnant women in developing countries.
" G* R5 A/ I/ ~; l6 r 词汇:# @2 J8 p4 g2 D8 c5 ~
multivitamin/7mQlti5vaitEmin/adj.多种维生素的 urge/E:dV/v.促进/v.极力主张;强烈要求;敦促 pregnant/5pre^nEnt/adj.怀孕的,妊娠的
1 G/ \1 d) N/ x Tanzania/7tAnzE5ni:E/n.坦桑尼亚(非洲国家) diabetes/7daiE5bi:ti:z, -ti:s/n.糖尿病,多尿症 Dar es Salaam/5dB:r es sE5lB:m/n.达累斯萨拉姆(坦桑尼亚首都)folate/5fEuleit/n.叶酸盐 mineral/5minErEl/n.矿物质;无机盐adj.矿物质的;无机的 fetal/5fi:tl/adj.胎儿的, 胎的2 l. l6 t; |: T
lymphocyte/5limfEsait/n.淋巴球, 淋巴细胞immunity/i5mju:niti/n..免疫力;免疫性 infection/in5fekFEn/n.传染,感染;传染病 placebo/plE5si:bEu/n.安慰剂;安慰剂治疗 inactive/in5Aktiv/adj.无作用的 pill/pil/n.药丸,丸剂fetus/5fi:tEs/n.胎,胎儿6 s7 A" {0 K- @2 W" u# ~4 A# a/ {
练习:
) D" p1 g' s) q7 v- C 1. How many babies are born with low birth weight in the developed countries every year according to WHO?0 u X. t) k4 g, F f; x l
A 20,000,000.- t8 {, X) h5 P
B 18,000,000.
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" M4 U- y, @" _- ~9 N' K5 M5 \& @ C 2,000,000. |