University of Copenhagen, Institute of Medical Anatomy, Sect. C, The Panum Institute, Blegdamsvej 3 C, DK-2200, Copenhagen N, Denmark.
Platelets. 1993;4(5):262-7. doi: 10.3109/09537109309013226.
Blood platelets are produced in the circulation by fragmentation of long, slender processes of cytoplasm formed from the megakaryocyte, the parent cell of platelets. Fragmentation occurs at local constrictions, forming 6 to 15 µm long, fusiform fragments (elongated proplatelets). The fusiforms transform into the circular, disc-shaped mature platelet by curving into a ring, which closes by fusion at the tips. The hole in the ring is finally filled in by a centripetal flow of membrane from the periphery. It is presumed that the curving of the fusiform is mediated by curving of its contained bundle of microtubules, which becomes the marginal bundle of the disc-shaped platelet. When curving begins in the fusiform, microtubules are closely associated with a membraneous tubule that becomes the submarginal tubule of the dense tubular system.
血小板是由巨核细胞的细胞质长而细的突起断裂形成的，巨核细胞是血小板的母细胞。在局部狭窄处发生断裂，形成 6 到 15 µm 长的梭形片段（伸长的前血小板）。梭形物通过弯曲成环转化为圆形、盘状的成熟血小板，在尖端融合闭合。环中的孔最终通过来自外周的膜向心流动来填充。据推测，梭形物的弯曲是由其内含的微管束的弯曲介导的，微管束成为盘状血小板的边缘束。当梭形物开始弯曲时，微管与一个膜管状结构紧密相关，该管状结构成为致密管状系统的亚边缘管状结构。
