Many forest tree species have multiple archegonia which, after fertilization produce a number of proembryos.许多林木树种都有颈卵器, 受精以后便产生许多原胚.She latched on to his arm, hooking her other arm around a tree.她拽住他的胳膊不放，另一只胳膊抱紧一棵树。The...
Strychnine, arsenic, and opium are poison.马钱子碱 、 砷和鸦片都是毒药.AIM : To study preparation of strychnine solid liposome.目的: 探讨番木鳖碱固体脂质体的最佳制备方法.Strychnine is used to kill rodents and pyrrolizidine alkaloids have significant act...