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Japanese doctors have used thin sheets of tissue(肌肉组织)from people’s cheeks repair damaged corneas（角膜）. A team from Osaka University transplanted thin layers of cheek cells onto the eyes of four patients with a rare and painful eye condition，reports BBC online. Patients whose vision had been cloudy could see well afterwards，and the“new corneas”remained clear more than a year after the operation.

Doctors can also take cells from a healthy eye and grow them in a dish to produce a new cornea，or they can transplant corneas from donors（捐献者）. But these techniques may not work when both eyes are too badly damaged by accident or disease.

The team hope their work may help solve the problem and lead to other types of grow－your－own tissue transplants. The cornea is the clear layer of cells on the surface of the eye. It can be damaged by trauma（外伤）or by a range of diseases.

The team worked with four patients who had a painful condition that causes cloudy corneas and dry eyes. Often the eye can regenerate(再生) cornea cells but none of the four patients had this ability. The researchers took a 3 mm－wide square of tissue from inside the mouth（cheeks）and grew it into a thin layer in the lab. They used a special low temperature technique to separate a very thin sheet off each batch. They then laid that onto the patient’s eye. The cell layers stuck onto the eye and developed into tissue that looked and acted like a healthy cornea.

However，long－term follow－up and experience with a large series of patients is needed to assess the benefits and risks this method. Yet，“it does offer the potential（潜能）of treating severe eye diseases that are resistant to standard approaches，”said the head of the research，Kohji Nishida.

48. Now doctors can repair the damaged corneas with the following methods Except_______.

A. by using mouth tissue

B. by taking cells from a healthy eye and growing them in a dish

C. by transplant corneas from another person

D. by using finger tissue

49. If both eyes are too badly damaged，we can treat them _________.

A. only by using mouth tissue

B. by taking cells from a healthy eye and growing them in a dish

C. by transplant healthy corneas from donors

D. by none of the mentioned method

50. We can infer from the passage___________.

A. the new technique can be widely used in the operations

B. the new technique needs to be further tested

C. the new technique has more benefits than risks

D. any new technique has risks

51. Which of the following is the best title？

A. A new invention

B. A new technique

C. Mouth tissue can restore your vision

D. Transplanting can restore your vision

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完成句子

Allow your muscles ________．(让你的肌肉完全放松。)

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阅读理解

　　Vitamin D helps bones and muscles(肌肉)grow strong and healthy．Osteoporosis is a common problem as people get older．Low levels of vitamin D can lead to some problems which are mainly found in children．Also, more and more research is suggesting that vitamin D might help prevent many diseases．

　　The easiest way to get vitamin D is from sunlight．But many people worry about getting skin cancer and skin damage from the sun．Darker skinned people produce less vitamin D than lighter skinned people．Production also decreases(减少)as people age, and people living in northern areas have lower levels of vitamin D than people in southern areas as they get less sunlight．

　　Not many foods naturally contain vitamin D．Foods high in this vitamin include oily fish, such as salmon, tuna and mackerel, and fish liver oils．Small amounts of vitamin D are found in beef liver, cheese and egg yolks．But most of the vitamin D in the American diet comes from foods, in which it has been added, like milk．

　　Research in the last several years has shown that low levels of vitamin D may increase the risk of heart attacks in men and deaths from some cancers．

　　More doctors are now having their patients tested for their vitamin D levels．But as research continues, some experts worry that if people take too much vitamin D, it might act as a poison．Also, skin doctors warn people to be careful not to stay in the sun too long because of the risk of skin cancer．

(1)

According to the first paragraph, osteoporosis is most probably a disease of the ________．
[　　]
A．	head
B．	heart
C．	bones
D．	skin

(2)

All of the following foods naturally contain Vitamin D EXCEPT ________．
[　　]
A．	salmon
B．	cheese
C．	egg yolks
D．	milk

(3)

According to the last paragraph, some experts worry that ________．
[　　]
A．	more and more people will have skin cancer
B．	too much vitamin D may harm people's health
C．	some people may refuse to have vitamin D level tests
D．	vitamin D may not be as important as doctors think

(4)

What can we learn from the passage?
[　　]
A．	Kids need vitamin D more than any other vitamin．
B．	Skin doctors don't want people to walk in the sun．
C．	Old people usually have higher levels of vitamin D than the young．
D．	People living in the south generally have higher levels of vitamin D than northern people．

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阅读理解。

     When a cat is frightened, its heart starts beating faster, its muscles (肌肉) get tense, and there are changes
in the chemicals in its blood-stream. If the danger continues, it will defend itself, or it will run away as fast as
possible.
     Something like this also happens to people. When we are excited, angry, scared or aroused by other
emotions, our bodies go through many physical changes, all of which make us more alert (警觉的) and ready
to react. We, too, get ready to defend ourselves or run. Human beings, however, have a problem that animals
never face. If we give way to our feelings and let them take over, we can get into trouble. Have you ever said
something in anger-or hit somebody-and regretted it later? Have you ever shouted at a teacher, told somebody
you were lonely, or said you were in love, and then wished later you had kept your mouth shout? It isn't
always wise to express your feelings freely.
     Does this mean that it's smarter always to hide our feelings? No! If you keep your feelings of anger,
sadness, and bitterness hidden away or bottled up inside, your body stays tense. Physical illnesses can develop,
and you can feel disturbed badly inside, it can actually be bad for your health. You can try to treat emotions as
if they were bananas in the cupboard.
     You can hide them and you can pretend they don't exist, but they'll still be around. And at last you'll have to
deal with them, just like those bananas.

1. By taking cat as an example, the author wants to show us that _______.

A. animals can't control their feelings
B. people can't control their feelings
C. people physical reactions are like those of animals in a way
D. people's bodies go through many physical changes in certain situations, too.

2. It's mentioned in the text that human beings get into trouble because ______.

A. we are not as alert as animals
B. we sometimes can't control our feelings
C. we always do something wrong to other people
D. we don't pay attention to our physical changes

3. The author wants to tell us in the last two paragraphs that ______.

A. there's no way to deal with our feelings
B. we should put some bananas in a cupboard when we're angry or scared
C. feelings will gradually disappear when we hold them in
D. we should neither express our feelings freely nor hide the bad feelings inside

4. The author's purpose in writing this article is to _______.

A. tell us that it's pretty good to keep our feelings inside
B. give some advice on how to express our feelings freely
C. make us deal with our feelings in a wise way
D. make us know it isn't always good to express our feelings freely

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At the beginning of this century, medical scientists made an interesting discovery: we are built not just of flesh(肌肉) and blood but also of time. They were 41 to show that we all have a ‘body clock’ 42 us, which controls the 43 and fall of our body energies, 44 us different from one day to the next.

The 45 of a ‘body clock’ should not be too 46 since the lives of most living things are controlled 47 the 24-hour night-and-day cycle(循环). We feel 48 and fall asleep at night and become 49 and energetic during the day. If the 24-hour cycle is 50 most people experience unpleasant 51 . For example, people who are not 52 to working at night can find that 53 of sleep causes them to 54 badly at work.

55 the daily cycle of sleeping and 56 , we also have other cycles which 57 longer than one day. Most of us would 58 that we feel good on some days and not so good on 59 ; sometimes our ideas seem to flow and at other times, they 60 do not exist.

A. anxious B. careful C. able D. proud

A. around B. inside C. between D. on

A. rise B. supply C. use D. movement

A. showing B. treating C. changing D. making

A. idea B. opinion C. story D. invention

A. difficult B. exciting C. interesting D. surprising

A. from B. over C. by D. during

A. dull B. dreamy C. tired D. peaceful

A. regular B. excited C. clear D. lively

A. shortened B. disturbed C. reset D. troubled

A. moments B. senses C. feelings D. effects

A. used B. allowed C. expected D. prevented

A. miss B. none C. need D. lack

A. show B. perform C. manage D. control

A. With B. Except C. As well as D. Rather than

A. waking B. moving C. living D. working

A. repeat B. remain C. happen D. last

A. believe B. agree C. realize D. allow

A. others B. the other C. all other D. other

A. only B. just C. still D. yet

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