Hematopoiesis of the other blood elements occurs in the fetal spleen.其他血液成分的生成发生在胎儿脾脏.Leukemias typically fill up the marrow with abnormal cells, displacing normal hematopoiesis.典型的白血病有很多不正常的细胞充满骨髓, 取代正常的造血功能.Objective :...
Car horns toot as cyclists dart precariously through the traffic.骑车人危险地在车流中飞速穿行时,汽车喇叭的嘟嘟声响成一片。The series of steep hills sapped the cyclists'strength.一连串坡度很大的小山耗尽了骑车人的气力.Cyclists who swerve to avoid dogs may fall off...