大多数禾本科胚有一片瓣 状 结构通常称为外胚叶.Most grass embryos have a flap - like structure known as the epiblast.目的: 研究少汗性外胚叶发育不全引起先天缺牙的ED1基因突变.Objective : To detect ED 1 gene mutation in three hypohidrotic ectodermal dysplasia ( HED ) nuc...
The plastic-covered seat has a few small splits around the corners.塑料面椅子的四角上有几道小裂缝。The river splits into three smaller streams at this point.这条河在此处分成三条小河.Usually only a trained dancer can do the splits.通常只有训练有素的舞蹈演员才会劈叉....