Sven is only this slim
斯文保持如此的身材
because of enormous efforts
是因为他的家庭与医生
on the part of his family and his doctor.
付出了巨大的努力
What happened was that the operation to remove the tumour
肿瘤摘除手术
somehow damaged his hypothalamus,
伤害到了他的下丘脑
an important nerve centre in the brain.
一个大脑中重要的神经中枢
Damage to his hypothalamus is
他的饮食习惯
what changed his eating behaviour.
因下丘脑的破坏而改变
Actually, we know that patients who have this tumour,
实际上 有这种肿瘤的病人
they don't die because of the tumour.
通常不会死于这种肿瘤
Most of them die because of the overweight that they develop.
而是死于由此引发的肥胖问题
Something in Sven's hypothalamus had to be keeping him hungry.
斯文下丘脑中的某些物质让他一直饥饿
Scientists knew that the hypothalamus
科学家知道 下丘脑
was involved in switching the appetite on and off.
与调控食欲有关
But decades of research had
但是几十年的研究并没有
brought them no closer to knowing exactly how.
让他们得知具体的调节原理
Then along came a big fat clue.
接下来的事 为此提供了重要线索
From the day it was born, this mouse had never stopped eating.
从出生那天起 这只老鼠从未停止进食
Researchers spent ten years
科学家花了十年的时间来
comparing this mutant mouse with other thin mice.
将这只基因突变的老鼠和其它瘦老鼠对比
And unexpectedly, they found
出乎意料地 他们在
the answer in the fat cells of the thin mouse.
瘦老鼠的脂肪细胞中找到了答案