早年贪吃晚年白痴_BEC初级作文_BEC初级-查字典英语网

早年贪吃晚年白痴

The most common cause of dementia, or severe cognitive decline, and the sixth leading cause of death in the U. S., Alzheimer's disease is marked by difficulty storing new memories and recalling recent events, loss of ability to track day-to-day information, a disrupted sense of time and space, social withdrawal, irritability, and mood swings. The neurodegenerative condition typically manifests after age 60. Life expectancy in the U.S. is currently about 78 years and rising. The 5.4 million Americans who suffer from the illness include 13 percent of those over age 65. 据调查，老年痴呆症已成为美国第六大杀手。痴呆症最常见症状是，认知能力急速下降，存储记忆困难，难以回忆发生事情，不能跟踪记住发生信息，没有时间与空间感觉，离群孤僻，个性暴躁和情绪极端不稳。特别是年龄超过60岁之后，这种神经衰退症状尤其突出。美国现在人口平均寿命大约为78岁，并有增加趋势。但是，美国患有痴呆症病的人数却有540万，其中有13%的痴呆病人年龄超过65岁；中国老年痴呆的患者数也呈显著上升趋势，据统计，目前患者总数约有600万，10%的病人年龄超过65岁。

Scientists attribute the debilitating disorder to the gradual accumulation between brain cells of a toxic protein, beta-amyloid, that blocks the transmission of information from cell to cell, wipes out synapses, and disrupts basic neuron function, leading to cell death. Inflammatory processes are also involved in memory loss. 科学家们认为，造成大脑失调不断恶化主要原因是，脑细胞毒蛋白与β（贝它）淀粉样蛋白逐渐沉淀积聚，阻碍细胞间信息传递，使神经突触消失，神经功能下降，从而导致细胞死亡。在这病变过程中，同时也引起记忆损失。