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.嘌呤为嘧啶取代或嘧啶为嘌呤所取代,叫做颠换.The substitution of a purine for a pyrimidine, or vice versa is a transversion.本文研究氟脲嘧啶(5—...
To calm his mind he began to take laudanum.为了镇定自己的神经,他开始服鸦片酊.Whipping and abuse are like laudanum; you have to double the dose as the sensibilities decline.谩骂与鞭打就好像鸦片, 敏感度降低时,必须加重其药量....
The general had mustered his troops north of the Hindu Kush.将军在兴都库什山脉以北集结军队。As a result , many Himalayan, Hindu Kush and Karakoram glaciers are dwindling.所以喜马拉雅山 、 兴都库什山和喀喇昆仑山的许多冰川都在逐渐萎缩.It is the oldest and largest Hind...
污染的器材和地面要用化学药物消毒.Contaminated instruments and floor surfaces should be chemically disinfected.轰吓 、 射杀或者用化学忌避剂可防止鸟类栖息.Perching can be discouraged by scaring, shooting or chemical repellants.过去曾设法用化学变性方法,提高纤维的抗磨损性能.There h...