Kind C
Anat Embryol (Berl). 1975 Aug 9;147(2):127-32. doi: 10.1007/BF00306727.
The circulating blood volume of the chick embryo was determined from the 4th up to the 18th day of hatching. In contrast to former studies, there was employed a radioisotope dilution method with albumin-bound I131. The findings are in close correspondence to those of the earlier studies. The blood volume does not display an entirely perfect curve of exponential growth, i.e., the doubling time increases steadily. The blood volume attains a peak value between the 16th and 18th day and decreases somewhat toward the end of the hatching period. There has been postulated a reduction of total red cell volume and hemoglobin caused by the involution of the extraembryonic circulatory system. The destruction of the erythrocytes seems to take place in the endodermal epithelium of the proximal yolk sac, where an accumulation of iron could be demonstrated on the 19th and 20th days.
从孵化的第4天到第18天测定了鸡胚的循环血量。与以前的研究不同，此次采用了结合白蛋白的I131放射性同位素稀释法。研究结果与早期研究结果密切相符。血量并未呈现出完全完美的指数增长曲线，即倍增时间稳步增加。血量在第16天至第18天之间达到峰值，并在孵化期接近结束时有所下降。据推测，胚外循环系统的退化导致总红细胞体积和血红蛋白减少。红细胞的破坏似乎发生在近端卵黄囊的内胚层上皮，在第19天和第20天可在该处证实有铁的积累。
