It is a question people have been asking for ages.Is there a way to turn back the aging process？
For centuries，people have been looking for a "fountain of youth".The idea is that if you find a magical fountain，and drink from its waters，you will not age.
Researchers in New York did not find an actual fountain of youth，but they may have found a way to turn back the aging process.It appears the answer may be hidden right between your eyes，in an area called the hypothalamus（下丘腦）.The hypothalamus is part of your brain.It controls important activities within the body.
Researchers at New York's Albert Einstein College of Medicine found that hypothalamus neural（神經(jīng)的）stem cells also influence how fast aging takes place in the body.
What are stem cells？They are simple cells that can develop into specialized cells，like blood or skin cells.Stem cells can also repair damaged tissues and organs.
Dongsheng Cai is a professor at the Albert Einstein College of Medicine.He was the lead researcher in a study on aging in mice.He and his team reported their findings in the journal Nature，Cai explained when hypothalamus function is in decline，particularly the loss of hypothalamus stem cells，and this protection against the aging development is lost.jye.ai eventually leads to aging.
Using this information，the researchers began trying to activate，or energize，the hypothalamus laboratory mice.They did this by injecting the animals with stem cells，Later，the researchers examined tissues and tested for changes in behavior.They looked for changes in the strength and coordination（協(xié)調(diào)）of the animals muscles.They also studied the social behavior and cognitive ability of the mice.The researchers say the results show that the treatment slowed aging in the animals，Cai says injecting middle-aged mice with stem cells from younger mice helped the older animals live longer.
But these results were just from studying mice in a laboratory.If the mice can live longer，does that mean people could have longer lives？The next step is to see if the anti-aging effects also work in.
（1）In Paragraph 2，a "fountain of youth" is mentioned to AA.
A．introduce the main topic
B．show a hidden secret
C．describe scientists research
D．recommend a way to stay young
（2）Aging takes place in the body when CC.
A．stem cells develop into specialized cells
B．there are important activities within the body
C．hypothalamus neural stem cells fail to protect against aging
D．the hypothalamus fails to repair damaged tissues and organs
（3）What do we know about the researchers at Albert Einstein College of Medicine from the text？ BB
A．They did experiments to see how stem cells work.
B．They studied mice to find their connection with humans.
C．They have found a possible way to slow the aging progress.
D．They have found no changes in mice's behavior during the experiment.
（4）What will the researchers probably do next？ DD
A．They will help some animals live longer.
B．They will announce the fountain of youth doesn't exist.
C．They will develop products to help people live a longer life immediately.
D．They will do research to see if what they have found in mice will apply to humans.
【答案】A；C；B；D
【解答】
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發(fā)布：2024/5/27 14:0:0組卷：1引用：1難度：0.5
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