The brown rat has prominent ears and a long scaly tail.

灰鼠长着两只突出的耳朵和一条带鳞片的长尾巴。

Objective: To evaluate effects of tRA on activity and content of UCP in rat brown adipose tissue mitochondria.

目的：探讨全反式维甲酸（t RA ）对大鼠棕色脂肪组织线粒体上解偶联蛋白（UCP）活性和含量的影响。

My cousin has a pet rat. It's white with brown spots and it's really fat because my cousin feeds it from the table all the time.

也许我该养一只宠物鼠，我堂弟就养了只带褐斑的小白鼠，它太胖了是因为堂弟整天喂它吃东西。