另两个为胸腺嘧啶和胞嘧啶, 即称为嘧啶的单环结构.The other two, thymine and cytosine, are single ring structures called pyrimidines.胞嘧 啶 核苷:当胞嘧啶通过β - 糖苷键与D- 核糖接合形成的核苷.Cytidine ( cytosine nucleoside ) A NUCLEOSIDE formed when cytosine is linked ...
商店售货员靠在柜台上漫不经心地招呼我。The shop assistant received me indifferently while leaning on a counter.那两名女售货员正忙着接待顾客。The two saleswomen were busily trying to keep up with the demand.售货员热情地和我打招呼。The salesperson greeted me with a war...