A healthy dose of sunshine may be the secret to staying young, British scientists have revealed.
Vitamin D is produced naturally by the skin in response to sunlight and may help to slow the aging process and protect against heart disease, according to the study.
Researchers from King's College London studied 2,160 women aged between 18 and 79, looking at their telomeres - a biological marker of ageing found in DNA. As people get older their telomeres get shorter and they become more susceptible to certain illnesses.
But the study found women with high levels of vitamin D had comparatively longer telomeres - a sign of being biologically younger and healthier.
The study suggests vitamin D may help to slow down the ageing process of DNA, and therefore the ageing process as a whole.
Lead researcher Dr Brent Richards said: "These results are exciting because they demonstrate for the first time that people who have higher levels of vitamin D may age more slowly than people with lower levels of vitamin D.
"This could help to explain how vitamin D has a protective effect on many ageing related diseases, such as heart disease and cancer."
He said further studies are required to confirm the findings.
Professor Tim Spector, head of KCL's twin research unit, and a co-author of the report, added: "Although it might sound absurd, it's possible that the same sunshine which may increase our risk of skin cancer may also have a healthy effect on the general ageing process."
Vitamin D made by the action of sunlight on the skin accounts for 90 per cent of the body's supply, but lower levels can also be obtained through food such as fish, eggs and breakfast cereals.
Other studies have suggested the vitamin plays a key role in protecting against cancer and heart disease.
1.The passage mentions all of the items listed below except_______.
A. The findings haven’t been confirmed entirely.
B. People become easily infected with some illnesses when they get older.
C. Vitamin D obtained through fish, eggs and breakfast cereals accounts for 10 percent of the body’s supply.
D. The discovery could help explain how vitamin D has a positive effect on cancer.
2.The phrase “demonstrate for” in the 7th paragraph probably means________.
A. claim B. prove C. think D. provide
3.It can be inferred that________.
A. Women with high levels of vitamin D have shorter telomeres.
B. Studies have confirmed the findings.
C. Sunshine may be a cause of the risk of skin cancer.
D. If someone has heart disease, sunshine may help him to relieve the disease.
4.The main idea of the passage is that_________.
A. Vitamin D can help protect against cancer and heart disease.
B. sunshine helps keep you young.
C. what effect vitamin D has on human’s body.
D. high levels of vitamin D make people keep young.
阅读下面短文,掌握其大意,然后从各题所给的四个选项（A、B、C和D）中,选出最佳选项，并在答题卡上将该项涂黑。
It is always interesting to visit another country, especially for those who have never traveled a great deal. 1travel can be very educational for anyone, 2he is interested enough to make preparations beforehand. 3the language of the new country would be 4for the traveler to attempt, 5the benefits of such an effort would become 6immediately after his arrival. It 7not seem important to him when he is comfortably situated at home, 8knowing how to 9a meal or rent a room is essential for the newcomer in a 10country. 11knowing the language, it is very difficult for the stranger to 12the people of the new country and 13customs.
Of course, in our small world, it is 14possible to find someone who understands 15own language, but this is only second-best for the traveler. To be 16, he can see places and things without the use of a language, 17places and things are 18the heart of any country. To get the greatest benefit from a trip to another country, it is indeed 19for the visitor to have an understanding of the 20.
1.A. national B. international C. domestic D. abroad
2.A. if B. unless C. since D. so
3.A. Knowing B. Saying C. Learning D. Studying
4.A. easy B. simple C. difficult D. impossible
5.A. and B. therefore C. although D. but
6.A. obvious B. invisible C. useful D. useless
7.A. did B. must C. may D. can
8.A. although B. but C. where D. when
9.A. order B. book C. cook D. eat
10.A. foreign B. familiar C. particular D. peculiar
11.A. By B. When C. With D. Without
12.A. meet B. see C. hear D. understand
13.A. his B. its C. their D. our
14.A. often B. never C. seldom D. only
15.A. his B. your C. our D. their
16.A. sure B. ensure C. insure D. honest
17.A. for B. but C. though D. as
18.A. usually B. not C. only D. very much
19.A. possible B. impossible C. useless D. important
20.A. country B. people C. language D. customs
Whom was it up to ________ the matter?
A. decide B. to decide C. deciding D. decided
He invited us to his birthday party but if she doesn’t go today, ________?
A. nor do I B. neither do I C. nor shall I D. neither I shall
______ his arrival, John was given a warm welcome by the local people.
A. For B. At C. On D. In
______ your proposal, I’m pleased to inform you that most committee members consider it acceptable.
A. ConsideringB. Regarding C. Seeing D. Supposing
