Space travel is definitely bad for astronauts’ bones, reducing their bone density(密度) after only a month of weightlessness, according to French research published on Friday.
Laurence Vico and his fellow workers at St Etienne University called for more research into the effects of microgravity, after their study of 15 astronauts from the Russian MIR station showed bone loss continued throughout space flights.
“Bone loss was especially striking in four astronauts, ” the scientists reported in the Lancet Medical Journal.
They measured the bone mineral density (BMD) of bones in the forearm(前臂) and lower leg of the astronauts who had spent one to six months in space.
The BMD loss was significant in the tibia(胫骨) of the lower leg, a weight-bearing bone, but barely changed in the radius(桡骨) of the forearm. “Our results indicate the need to investigate not only different bones, but also different areas of the same bone since not all sites of the skeleton (骨架) are similarly affected by space conditions, ” they added.
Without gravity the body isn’t bearing any weight so there is no need for calcium (钙) which makes bones strong, and it becomes empty into the bloodstream.
The research team suggested in future scientists should try to determine if the loss of bone density was only on weight-bearing bones on longer flights, also the possible recovery after returning to Earth.
1.French scientists did their research on Russian astronauts, because _______.
A. they only cared for the Russian astronauts
B. they were not interested in their own astronauts
C. the Russian government invited them to do their research
D. the Russian astronauts worked in space for a long time
2. Scientists have found that _______.
A. the BMD loss may cause serious illness to astronauts
B. the BMD loss may cause some change in astronauts’ bodies
C. astronauts shouldn’t care about the BMD loss
D. astronauts should take some calcium before space travel
3. What cause the BMD loss to astronauts, according to this passage?
A. The food they eat in space. B. The drinks they take in space.
C. The temperature in space. D. The gravity in space.
4.In the third paragraph, the word “striking” means ______.
A. unusual B. simple C. weak D. slow
If you see someone drowning, speed is very important. Once you get him out of the water, if he isn't breathing, you have four minutes before his brain is completely destroyed. Support his neck, move his head back and press his chin upwards. This stops the tongue blocking the airway in the throat and is sometimes enough to get him breathing again. If that doesn't work, start mouth-to-mouth breathing. Press his nostrils (the two holes at the end of your nose, through which you breathe and smell things) together with your fingers. Open your mouth and take a deep breath. Blow into his lungs until his chest rises, then remove your mouth and watch his chest fall. Repeat twelve times a minute. Keep doing until professional help arrives.
To bring a child back to life, keep your lips around his mouth and gently blow into his mouth. Give the first four breaths as quickly as possible to fill the blood with oxygen. If, in spite of your efforts, he starts turning a blue-grey colour, and you can feel no pulse, then pressing is the last chance of saving his life.
With arms straight, rock forwards, pressing down on the lower half of the breastbone. Don't be too hard or you may break a rib. Check how effective you are by seeing if his colour improves or his pulse becomes independent to your chest pressing. If this happens, stop the pressing. Otherwise continue until rescue arrives.
1.If you want to save someone drowning, you __________.
A. have to pull off his clothes first . B. should try to get him out of water as quickly as possible.
C. should first make out who he is. D. ought to throw a life coat to him first .
2.Once a person stops breathing, it means ___________.
A. you have no more than 4 minutes to bring him to life again .
B. his brain is completely damaged .
C. he has passed away .
D. there is no way to save his life .
3.To press his chin upwards is a way to _____________.
A. keep the tongue from blocking the airway in the throat.
B. prevent the tongue from stopping the airway in the throat.
C. wipe the tongue out of the throat .
D. see if he can possibly be saved .
4.If the drowning boy has no pulse,_____________.
A. press his chin upwards is enough to get him breathing .
B. blow air into his mouth is sure to save his life .
C. press his nostrils together with your fingers can work .
D. press is the last chance of saving his life .
5.Which of the following statement is true?
A. Don’t stop pressing his chest, if the drowning man starts breathing again.
B. If you see someone drowning, you must give him mouth-to-mouth breathing.
C. If a man does not breathe for four minutes, his brain will be completely destroyed.
D. When pressing, you can do it as hard as you can.
My father often works very hard. And he has 21 to see a film. Here I’ll tell you 22 about him.
One afternoon, when he finished his work and 23 go home, he found a film ticket under the 24 on his desk. He thought he 25 to have not much work to do that day and 26 was quite wonderful to pass the 27 at the cinemA. So he came back home and 28 finished his supper. Then he said 29 to us and left.
But to our 30 , he came back about half an hour later, I 31 him what was the matter. He smiled and told us about 32 funny thing that had happened at the cinema.
When my father was sitting in his seat, a 33 came to my father’s and said that the seat was 34 . Ｍy father was surprised. He took out the ticket 35 looked at it carefully. It was Row17, 36 . And then he looked at the seat. It was the same. So he asked her 37 her ticket. She took out the ticket at once and the seat shown in it was Row 17, Seat 3.
38 ? What’s the matter with all this? While they were wondering suddenly the woman said, “The 39 of the tickets are different.” So they looked at the ticket more carefully. After a while, my father said, “Oh, 40 , I made a mistake. My ticket is for the film a month ago. Take this seat, please.” With these words, he left the cinema.
1. A. little money B. much money C. little time D. much time
2.A. a funny story B. a good story C. an old story D. a strange story
3.A. was to B. was about to C. had to D. ought
4.A. box B. book C. glass D. paper
5.A. happened B. liked C. pretended D. wanted
6.A. it B. this C. that D. which
7.A. morning B. afternoon C. day D. evening
8.A. early B. quietly C. quickly D. suddenly
9. A. hello B. good-bye C. good evening D. good night
10. A. disappointment B. joy C. sorrow D. surprise
11. A. asked B. explained C. told D. wanted
12.A. a B. one C. some D. the
13. A. man B. woman C. doctor D. nurse
14. A. hers B. his C. taken D. wrong
15. A. and B. but C. or D. so
16. A. Seat1 B. Seat2 C. Seat3 D. Seat4
17.A. it bring B. to get C. to see D. to show
18.A. Why B. How C. When D. where
19.A. designs B. colors C. prices D. owners
20.A. I’m sad B. I’m sorry C. I’m wrong D. I’m worried
_____, your composition is full of mistakes.
A. Writing carelessly B. Written carelessly
C. Having written carelessly D. Being written carelessly
_____ with so much trouble, we failed to complete the task on time.
A. Faced B. Face C. Facing D. To face
The couple _____ last year. They had lived together for twenty years, though.
A.broke out B.broke away C.broke up D. broke down
