注释：

1.  beauty product：美容产品

2.  quantum dot (QD)：量子点。可取代传统染色法，成为细胞内的荧光标记物，可进行长时间、多分子、同时检测。

3.  give off：放出；发出（蒸汽、光线、烟雾、气味等）

4.  Researchers are studying ways to program them to identify diseases by lighting¹ up in the presence of a targeted molecule².  研究人员正在研究为它们编程的方法，以便如果有靶分子存在时能通过发光辨认疾病。light up点灯；发光。targeted molecule：靶分子。

5.  National Institutes of Health (NIH)：国立卫生研究院

6.  side effect：副作用

7.  compared to larger particles如果与大一点的颗粒比较起来的话。这是一个过去分词短语，作条件状语。compare…to在美国英语也可以表示compare…with的意思。

练习：

1.  Which of the following uses of nanotechnology is NOT mentioned in the passage?

A)     To make beauty products and dirt-resistant clothing.

B)      To produce better and lighter³ building materials.

C)     To help more accurately⁴ diagnose diseases.

D)     To help more effectively treat diseases.

2.  How can quantum dots be used to confirm diseases?

A)  By traditionally looking at a person's blood under a microscope.

B)  By letting a person take some kind of medicine.

C)  By lighting up in the presence of a targeted molecule.

D)  By subjecting a person to an X-ray examination.

3.  How can nanotechnology be used to make a drug more effective?

A)  By making a drug target the focus of a disease.

B)  By changing the structure of the body cells.

C)  By lowering the side effects caused by a drug.

D)  By letting a patient take a dose as large as possible.

4.  The following developing countries are doing very well scientific research on nanotechnology EXCEPT            .

A)  China

B)  Brazil

C)  Iran

D)  India

5.  Which of the following is the possible risk in using nano-materials mentioned in the passage?

    A)  They may cause some damage to the body cells.

    B)  They are harmful materials themselves.

    C)  They may store in the body.

    D)  They may behave differently in the body and the environment.

答案与题解：

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。

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。

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。

4.  C　第五段第二句已经说得很清楚，其中并没有Iran。 

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。