VOA标准英语2011--Stem Cell Treatment Boosts Heart Function

Stem Cell Treatment Boosts Heart Function

 

A stem cell treatment for patients with heart failure significantly improved their heart function in a small but promising¹ new study.

In heart failure, the heart loses its ability to efficiently² pump blood. It is most often caused by a heart attack, which destroys some of the muscle tissue essential to a normal heartbeat.

In this new study, patients were injected with adult stem cells taken from their own hearts. These are a special kind of undifferentiated cell found throughout the body that helps to maintain and repair the tissue in which they are found.

Doctors use a measure called 'ejection fraction' to describe the heart's ability to pump blood. Study author Dr. Roberto Bolli of the University of Louisville says people in the control group showed no significant improvement in that measure. But he called the improvement in the stem cell patients "striking."

"At four months, the pumping ability of the heart was markedly improved," he reports. "The ejection fraction increased by eight points at four months, and at one year it increased by 12 points. Now, this is a huge increase, much greater than what we even hoped for when we started our study."

The heart's ability to pump blood improved after patients were injected with adult stem cells taken from their own hearts, according to a study led by Dr. Roberto Bolli of the University of Louisville.

And Bolli says there was a significant improvement in the ability of the stem cell recipients³ to exercise.

The study participants also got MRI scans before and after treatment. A year after getting the stem cells, the images showed a 30 percent reduction in the scars of dead heart muscle.

"The reduction of the scar implies that new heart muscle is being produced to replace that scar. And so it is evidence that the stem cells are regenerating⁴ new heart muscle."

This ongoing⁵ study is very small, with just 16 patients in the stem cells group, plus seven more in the control group. But a commentary published with his paper says Bolli's findings "raise new optimism" because of the study's rigorous quality and unexpectedly good results.

Bolli published his findings in The Lancet and presented them at the American Heart Association meeting in Florida.

Also at that Heart Association meeting: another report of stem cell research, though with less promising results. In a study published in the journal of the American Medical Association, JAMA, researchers gave recent heart attack victims stem cells taken from their bone marrow⁶. The idea was to prevent the onset⁷ of heart failure. Earlier studies had suggested the technique might work. But in this case, after six months there was no improvement in heart function.

1 promising   

adj.有希望的，有前途的

参考例句：

• The results of the experiments are very promising.实验的结果充满了希望。
• We're trying to bring along one or two promising young swimmers.我们正设法培养出一两名有前途的年轻游泳选手。

2 efficiently   

adv.高效率地，有能力地

参考例句：

• The worker oils the machine to operate it more efficiently.工人给机器上油以使机器运转更有效。
• Local authorities have to learn to allocate resources efficiently.地方政府必须学会有效地分配资源。

3 recipients   

adj.接受的；受领的；容纳的；愿意接受的n.收件人；接受者；受领者；接受器

参考例句：

• The recipients of the prizes had their names printed in the paper. 获奖者的姓名登在报上。 来自《简明英汉词典》
• The recipients of prizes had their names printed in the paper. 获奖者名单登在报上。 来自《现代英汉综合大词典》

4 regenerating   

v.新生，再生( regenerate的现在分词 )；正反馈

参考例句：

• It is not proposed to deal with the detailed histology of regenerating tissues here. 这里未提出详细的再生组织的组织学。 来自辞典例句
• This is accomplished by using a thermocompressor to recycle regenerating steam through the absorber. 它用热压机使再生蒸汽经吸附器循环完成解吸过程。 来自辞典例句

5 ongoing   

adj.进行中的，前进的

参考例句：

• The problem is ongoing.这个问题尚未解决。
• The issues raised in the report relate directly to Age Concern's ongoing work in this area.报告中提出的问题与“关心老人”组织在这方面正在做的工作有直接的关系。

6 marrow   

n.骨髓；精华；活力

参考例句：

• It was so cold that he felt frozen to the marrow. 天气太冷了，他感到寒冷刺骨。
• He was tired to the marrow of his bones.他真是累得筋疲力尽了。

7 onset   

n.进攻，袭击，开始，突然开始

参考例句：

• The drug must be taken from the onset of the infection.这种药必须在感染的最初期就开始服用。
• Our troops withstood the onset of the enemy.我们的部队抵挡住了敌人的进攻。