根据材料,完成题。 Stem Cell Therapy May Help Repair the Heart According to scientists in

第1题

根据以下材料，回答题Stem Cell Therapy May Help Repair the HeartAccording to scientists in t

根据以下材料，回答题

Stem Cell Therapy May Help Repair the Heart

According to scientists in the USA， stem cell therapy may one day be able to repair the hearts of people with heart failure. Researchers at Pittsburgh University School of Medicine examined 20 patients who had severe heart failure and were going to have surgery.

They injected stem cells into the parts of their hearts that were damaged. They then compared their hearts with those of people who had undergone surgery without having the stem cells injected into them （they had also suffered from severe heart failure）. The patients who had had the stem cells injected had hearts that were able to pump （用泵抽运） more blood than the others.

According to Professor Robert Kormos， one of the researchers， these results could revolutionize heart treatment. Although previous studies had indicated that there might be a benefit， this is the first study that has actually proved that stem cell therapy can help the failing heart work better.

All the patients in this study had hearts that could not pump blood properly. The scientists measured their ejection fraction （射血分数）. It is a measure of heart performance; it measures how much blood is being pumped out by the left ventricle （心室）.

Healthy people"s ejection fraction is about 55%. These patients had ejection fraction of under 35%. They all had by-pass surgery （搭桥手术） performed on them. Some of the patients had stem cells taken from their hip bones and injected into 25-30 sites in the damaged heart muscle. Six months later their ejection fraction rate was 46.1% while those who just had surgery but no stem cell injections averaged 37.2%. No side effects were reposed.

Heart failure is a common problem all over the world. In the U.K. alone about 650，000 people suffer from heart failure every year. As the number of people suffering from heart failure increases in the world in general， these findings are particularly significant.

Current treatments relieve the symptoms. This new stem cell therapy actually repairs the damaged muscle in the heart and has the potential of curing the disease.

The 20 patients had stem cell injections instead of surgery. 查看材料

A.Right

B.Wrong

C.Not mentioned

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第2题

Stem cell therapy seems to have great prospects. 查看材

料

A.Right

B.Wrong

C.Not mentioned

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第3题

干细胞（stem cell)

干细胞(stem cell)

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第4题

embryo stem cell

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第5题

Hwang's team has published some milestone papers in stem cell research.A．YB．NC．NG

Hwang's team has published some milestone papers in stem cell research.

A．Y

B．N

C．NG

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第6题

根据下面材料，回答题。 Human Heart Can Make New CellsSolving a longstanding mystery, scien

根据下面材料，回答题。

Human Heart Can Make New Cells

Solving a longstanding mystery, scientists have found that the human heart continues to generate new cardiac cells throughout the life span, although the rate of new cell production slows with age.

The finding, published in the April 3 issue of Science, could open a new path for the treatment of heart diseases such as heart failure and heart attack, experts say.

"We find that the beating cells in the heart, cardiomyocytes, are renewed," said lead researcher Dr. Jonas Frisen, a professor of stem cell research at the Karolinska Institute in Stockholm, Sweden.

"It has previously not been known whether we were limited to the cardiomyocytes we are born with or if they could be renewed," he said.

The process of renewing these ceils changes over time, Frisen added. In a 20-year-old, about 1 percent of cardiomyocytes are exchanged each year, but the turnover rate decreases with age to only 0.45 percent by age 75.

"If we can understand how the generation of new cardiomyocytes is regulated, it may be potentially possible to develop pharmaceuticals that promote this process to stimulate regeneration after, for example, a heart attack," Frisen said.

That could lead to treatment that helps restore damaged hearts. "A lot of people suffer from chronic heart failure," noted co-author Dr.Ratan Bhardwaj, also from the Karolinska Institute.

"Chronic heart failure arises from heart cells dying," he said.

With this finding, scientists are "opening the door to potential therapies to having ourselves heal ourselves," Bhardwaj said. "Maybe one could devise a pharmaceutical agent that would make heart cells make new and more cells to overcome the problem they are facing."

But barriers remain. According to Bhardwaj, scientists do not yet know how to increase heart cell production to a rate that would replace cells faster than they are dying off, especially in older patients with heart failure. In addition, the number of new cells the heart produces was estimated using healthy hearts--whether the rate of cell turnover in diseased hearts is the same remains unknown.

The human heart stops producing cardiac cells____________. 查看材料

A.when a person is born

B.when a person becomes old

C.when a person gets sick

D.when a person dies

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第7题

The many different cell types in the blood of an adult mammal are derived from（).

A.a single type of multipotent stem cell found in the bone marrow

B.differentiated cells that first developed in the fetal liver, but now reside in the bone marrow

C.division of differentiated cell types while circulating in the blood

D.stem cells that became committed to each specific blood celll type during embryonic development

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第8题

What do we learn about a stem cell？A．It has no difference from other cells.B．It can only b

What do we learn about a stem cell？

A．It has no difference from other cells.

B．It can only become a certain type of cell.

C．It can't become a kidney cell.

D．It maintains and repairs the body.

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第9题

Why do some people oppose stem cell research according to the man？A．They don't know about

Why do some people oppose stem cell research according to the man？

A．They don't know about the benefits of the research.

B．The research goes against their religious beliefs.

C．The research costs too much money.

D．They insist that the research is against nature.

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第10题

听力原文：M: The Republican Party in America is opposing stem cell research. I find it hard

to believe that in this day and age,someone would do that.

W: Stem cell research sounds pretty impressive,I'll admit.But just what is it？

M: Well,a stem cell is a special type of cell.It is a general cell that.when it divides.Call become any specific type of cell.

W: You mean,a stem cell can become a heart cell？Or a brain cell or a kidney cell？

M: That's about it.Stem cells are a part of the body's maintenance and repair system.When they divide, they can become any cell type.

W: I guess there would be some tremendous medical advantages in that sort of research.

M: You've said a mouthful.Recently,scientists were able to help a man who lost a jawbone from cancer.They recreated bone material for his jaw from stem cells.What it means is that since the new bone was created out of the person's own cells,there was no problem with rejection because the DNA was the same.

W: I bet the person was delighted.Why would anyone oppose that sort of research？It would seem to have endless potential to benefit the human race.

M: I agree,but there are people who think we should not interfere with nature and mainipulate"what is not natural".

W: It is easier to hold such a narrow view if you're not in a position to need the benefits of the research.If you're missing a jawbone because of cancer,you probably support the research.

What is the man's attitude toward the stem cell research？

A．Supportive.

B．Opposed.

C．Pessimistic.

D．Neutral.

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根据材料，完成题。 Stem Cell Therapy May Help Repair the Heart According to scientists in