1.That is to say, I believe that the Internet has positive effects on our lives.

7.One theory suggests that acupuncture blocks pain signals from reaching the spinal cord brain.

M7U3

6.How acupuncture reduces and relieves pain is unclear.

5.However, it was not until World War II that two other scientists, Howard Florey (Australian) and Ernst Chain (German-born English), managed to use new chemical techniques to purify it.

4.Lawrence Craven, a doctor from the USA, is the author of several published reports, one of which introduced the idea in 1953 that aspirin could reduce the risk of heart attacks by thinning blood.

3.Not only has aspirin saved many people’s lives by reducing fever and helping stop pain, but there are also other things that aspirin can help with.

2.It was in 1875 that a European chemist called Doctor Felix Hoffmann produced acetylsalicylic acid (ASA) from some other chemicals to make a medicine for his father.

1.If you open up any medicine cupboard in the world, there is a high probability that you will find aspirin and penicillin.

13.For the time being, at least, I see no scientific reason to stop using my own mobile phone.

M7U2

12.That does not necessarily mean that they should be used without caution.