手机APP下载

您现在的位置: 首页 > 英语听力 > 实战英语听力 > 经济学人双语拓展 > 正文

经济学人双语拓展(MP3+文本) 第16期:为什么老年痴呆症仍然是一个医学之谜?

来源:可可英语 编辑:Melody   可可英语APP下载 |  可可官方微信:ikekenet
 下载MP3到电脑  批量下载MP3和LRC到手机

As populations have aged, dementia has soared to become the fifth leading cause of death worldwide. Alzheimer's disease, a form of dementia, accounts for most of these cases. Tens of billions of dollars have been spent on Alzheimer's research over the past several decades but still there is no cure. All attempts to halt the progression of the disease have failed. Now many major drug companies have pulled out of research altogether. So why is Alzheimer's disease still such a medical mystery?

老年痴呆

One of the signs of Alzheimer's in the brain is damage of connections and the loss of large numbers of neurons over time. It affects the hippocampus and its connected structures making it harder to form new memories or learn new information. As damage spreads through the brain the cortex becomes thinner and more memories are lost. Although emotional responses can often remain. As the brain shrinks further it slowly alters personality and behaviour and eventually the ability to live and function independently. For 35 years there has been scientific disagreement about the origins of the disease. The main area of debate has focused on the abnormal build up of clumps of protein called amyloid plaques often found in brains of those affected by Alzheimer's. But all attempts to target this protein with drugs have failed. A new study is now challenging the way science thinks about the disease. The study suggests that the bacterium Porphyromonas gingivalis, which is involved in gum disease, may contribute to Alzheimer's. In studies on mice the bacterium can cause brain inflammation, neural damage, and amyloid plaques. The researchers went on to show in mice this damage could be stopped using drugs that target the toxic enzymes. There is more to this story though. The risk of Alzheimer’s is higher in those who have severe head injuries and also for those with an arterial disease known as atherosclerosis. This suggests there are many causes with one end point. And scientists hope that finding an underlying cause that could tie these together will hold the key to better treatments in the future.

关注公众号知问导图,回复TEX,免费获取本期内容详解等更多精彩内容。


重点单词   查看全部解释    
challenging ['tʃælindʒiŋ]

想一想再看

adj. 大胆的(复杂的,有前途的,挑战的) n. 复杂

 
eventually [i'ventjuəli]

想一想再看

adv. 终于,最后

 
contribute [kən'tribju:t]

想一想再看

vt. 捐助,投稿
vi. 投稿,贡献,是原因

联想记忆
inflammation [.inflə'meiʃən]

想一想再看

n. 发炎,红肿,炎症

 
affected [ə'fektid]

想一想再看

adj. 受影响的,受感动的,受疾病侵袭的 adj. 做

联想记忆
toxic ['tɔksik]

想一想再看

adj. 有毒的
n. 有毒物质

联想记忆
soar [sɔ:, sɔə]

想一想再看

vi. 翱翔,高飞,猛增,高涨,高耸
n. 翱

 
function ['fʌŋkʃən]

想一想再看

n. 功能,函数,职务,重大聚会
vi. 运行

 
abnormal [æb'nɔ:məl]

想一想再看

adj. 反常的,不正常的,不规则的
n. 不

联想记忆
disagreement [.disə'gri:mənt]

想一想再看

n. 不合,争论,不一致

 

发布评论我来说2句

    最新文章

    可可英语官方微信(微信号:ikekenet)

    每天向大家推送短小精悍的英语学习资料.

    添加方式1.扫描上方可可官方微信二维码。
    添加方式2.搜索微信号ikekenet添加即可。