在一些细胞中观察到界限清楚的中心体.Clearly defined centrosomes have been observed in some cells.每个 动物细胞 跟植物细胞不同,都有一对中心体.Every animal cell ( but not plant cells ) contains a pair of centrioles.目前的研究表明中心体异常在人类恶性肿瘤中普遍存在.Recent studies revea...
人们只得在陡峭而泥泞的斜坡上艰难地行进。The men had to slog up a steep muddy incline.路上不时会有吹聚起的积雪，泥泞而湿滑。Here and there a drift across the road was wet and slushy.骆驼的蹄子虽然非常适合于在干沙上行走，碰到泥泞时却无计可施。The camel's feet, well adapted for dry sand...
This obviously derails the forward - momentum process.很明显这是前进途中的一大障碍.Longitudinally polarized electrons are the electrons with spin and momentum pointing in the same direction.纵向极化电子,就是自旋和动量方向相同的电子.In the case of populat...