英语新闻听写 摄入过多糖类对癌细胞非常有利（在线收听）

Sugar is bad for you, right? Everybody knows that. But it's very good for one thing--cancer cells. According to Science Magazine, cancer tissues have extra sugars that bind to the protein Siglec-9 on natural killer cells.

糖对身体有坏处，对吗？人人都知道。但是它对一样东西特别有利——癌细胞。根据《科学杂志》，癌组织上有与自然杀伤细胞蛋白样凝集素9捆绑在一起的额外糖类。

In doing so, they quiet the immune response and make the body less able to fight off the deadly enemies. To our defense system, cell-surface sugars are a molecular fingerprint--and a type of Harry Potter-like invisibility cloak--telling a roving immune cell, "This one's OK. Move along." Certain pathogens, such as the bacteria that cause gonorrhea or streptococcal infections, have taken advantage. They coat themselves with sialic acids to hide from the immune system.

这样它们就能平息免疫反应，让身体无法对抗致命的癌组织。对防御系统而言，细胞表面的糖类就是分子指纹，它们像穿着一层隐身衣一样，甄别移动的免疫细胞，“这个没问题，继续走。”有些病原体，比如导致淋病或链球菌感染的细菌正好利用了这一点。它们用唾液酸将自己包裹起来躲避免疫系统的侦查。