题型:阅读理解 题类:常考题 难易度:普通
江苏省连云港市2018-2019学年高二上学期英语期末考试试卷
Drug companies have spent billions of dollars searching for therapies to reverse or significantly slow Alzheimer's disease, but in vain. Some researchers argue that the best way to make progress is to create better animal models for research, and several teams are now developing mice that more closely imitate how the disease destroys people's brains.
The US National Institutes of Health (NIH), the UK Dementia Research Institute and Jackson Laboratory (JAX) - one of the world's biggest suppliers of lab mice - are among the groups trying to genetically design more suitable mice. Scientists are also exploring the complex web of mutations(突变) that influences neurological (神经学的) decline in mice and people.
"We appreciate that the models we had were insufficient. I think it's sort of at a critical moment right now." says Bruce Lamb, a neuro-scientist at Indiana University ~ho directs the NIH-funded programme.
Alzheimer's is marked by cognitive impairment(认知损伤) and the build-up of amyloid-protein plaques (淀粉样蛋白块) in the brains of people, but the disease does not occur naturally in mice. Scientists get around this by studying mice that have been genetically modified to produce high levels of human amyloid protein. These mice develop plaques in their brains, but they still do not display the memory problems seen in people.
Many experimental drugs that have successfully removed plaques from mouse brains have not lessened the symptoms of Alzheimer's disease in people. One focused stumble came last month, when three companies reported that their Alzheimer's drugs had failed in large, late-stage clinical trials. Although the drugs successfully blocked the accumulation of amyloid protein in mice, they seemed to worsen cognitive decline and brain shrinkage in people.
The drive for better mouse models comes as genomics studies are linking the most common form of Alzheimer's to dozens of different genes. This diversity suggests that each case of the disease is caused by a different combination of genetic and environmental factors. "There is no single Alzheimer's disease," says Gareth Howell, a neuro-scientist at Jackson Laboratory (JAX) in Bar Harbor, Maine.
Howell argues that scientists' reliance on lab mice with only a few genetically engineered mutations might have limited research. His own work suggests that in mice, just as in people, genetic diversity plays a part in determining how Alzheimer's develops.
Admission & Opening Times
Museum Opening Times
The museum is open daily: 10 am—5 pm
Collections Centre opens daily: 11am—5 pm
Last admission to the museum and Collections Centre is 4: 30 pm.
Closed: December 24, 2017—January 1, 2018 inclusive
Museum Admission
Adult | £14 |
Child(5-16yrs) | £9 |
Under 5's | FREE |
Concession(优惠)(60 yrs+, unemployed, student) | £12 |
Family ticket(2 adults, 3 children) | £39 |
Groups of 12 or more(pre-booking essential) | £9 |
Your entry fee will be treated as a donation to our charity on which we may also be able to claim Gift Aid. In return you will receive FREE admission to the museum for a year with our Annual Pass (this excludes 5Special Show Days per year).
Tickets for today's date are only available to buy at the museum.
Museum Tours
An optional tour of the museum is included in your entry fee. The tours are available between 11:15 am and 2:15 pm every day. They do not have to be pre-booked but have time limits.
Collections Centre
Access to the Collections Centre is included in your entry fee, so you will just need to show your museum admission ticket at the door to gain entry. The Collections Centre is open from 11am to 5 pm with last entry at 4:30 pm.
Show Days
On most show days the normal museum entry prices are applied. There are, however, five Special Show Days per year when the admission price varies, including entry both into the show and the museum. On these days, Gift Aid tickets and promotional vouchers(促销券) are not valid. Advance discounted Show Day tickets are available online or via our Ticket Hotline 019 -266 45033.
For more information about the British Motor Museum, please click here.
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