Bancroft M, Bellairs R
J Embryol Exp Morphol. 1976 Apr;35(2):383-401.
The notochord of the chick embryo between stages 5 and 23 inclusive has been studied by scanning electron microscopy, supplemented by transmission electron microscopy. Three main phases of development are described, and these have been designated: bilaminar; rod-like, unvacuolated; rod-like and vacuolated. The changes in shape of the organ from bilaminar to rod-like is accompanied by changes in the shape, orientation and position of the cells, an increase in the complexity of the cell contacts, and the laying down of a basal lamina. The change from the unvacuolated to the vacuolated phase is accompanied by increasing complexity within the cytoplasm. Most of the vacuoles are intracellular and appear empty though some contain a granular material. The notochordal sheath appears to be secreted by the notochordal cells and fine fibrillar material has been seen in the intercellular spaces. By stage 23, most of the notochordal cells have become so highly vacuolated that the cytoplasm has become closely packed around the nucleus.
通过扫描电子显微镜并辅以透射电子显微镜，对第5至23阶段（含）的鸡胚脊索进行了研究。描述了发育的三个主要阶段，分别命名为：双层；杆状，无液泡；杆状且有液泡。器官从双层变为杆状的过程中，细胞的形状、方向和位置发生变化，细胞接触的复杂性增加，同时基底膜形成。从无液泡阶段到有液泡阶段的转变伴随着细胞质内复杂性的增加。大多数液泡位于细胞内，看起来是空的，不过有些含有颗粒物质。脊索鞘似乎由脊索细胞分泌，细胞间隙中可见细纤维物质。到第23阶段时，大多数脊索细胞已高度液泡化，以至于细胞质紧密包裹在细胞核周围。
