Researchers in the US say they might have discovered how to fight against and even reverse some processes of ageing, at least in mice. Injecting the blood of young mice into the older ones improved their brainpower, a study found. Scientists at Stanford University plan to carry out trials in people in the hope that new treatments for dementia(痴呆症) can be developed.
“There are factors present in blood from young mice that can recharge an old mouse’s brain so that it functions more like a younger one,”says Dr. Tony from Stanford University School of medicine. In the study published in Nature Medicine, mice aged 18 months were given injections of the blood taken from mice aged 3 months. The injected mice performed better on memory tests than mice of the same age that had not been given the blood. Dr. Tony said it was not known whether the same was true of humans, but a trial was planned.
A research center in UK said the treatment restored certain aspects of learning and memory in mice, but was of unknown importance to humans. The research, while very interesting, did not test the type of brain damage that was seen in dementia, which is not a necessary consequence of ageing.
Meanwhile, two similar studies by a separate team have thrown more light on how young blood may benefit the old, in mice at least. A substance in the blood of mice previously shown to have an anti-ageing effect on heart muscle also improved brain cells, according to a Harvard team. The research, published in Science, found the blood factors encouraged the growth of brain cells in old mice, and restored their sense of smell. The same chemical also improved muscle power of aged mice, the researchers found.
The underlined word in paragraph 1 probably means _________.

A．change	B．destroy
C．speed	D．increase

Scientists in the US will test the discovery in humans with the aim of __________.

A．proving the possibility to live longer.

B．showing the importance of scientific research.

C．publishing the study in Nature Medicine.

D．treating an age-related disease successfully.

According to the studies, the blood from young mice benefits the old in certain ways except in_________.

A．memory	B．muscle power
C．fur color	D．brain cells

What’s the author’s attitude to the anti-ageing studies?

A．supportive	B．objective
C．negative	D．doubtful