FELDHERR C M
J Cell Biol. 1962 Jul;14(1):65-72. doi: 10.1083/jcb.14.1.65.
Colloidal gold particles, 25 to 55 A in diameter, which had been coated with polyvinylpyrrolidone, were microinjected into the ground cytoplasm of amebas (Chaos chaos). At time intervals of 1 minute, 2 minutes, 10 minutes, and 24 hours after injection the cells were fixed for electron microscopy. After 24 hours, gold particles were found in both the nuclei and the ground cytoplasm, the concentration being higher in the nuclei. Colloidal particles were also present in the nuclei after 10 minutes, but at this time interval the concentration did not appear to be greater than that in the ground cytoplasm. One and 2 minutes after injection, the gold particles were located almost exclusively in the ground cytoplasm; however, individual particles were often found within the annuli of the nuclear envelope, and were located specifically in the centers of these structures. The results suggest that at least some of the gold particles which enter the nuclei pass through the annuli, and that passage through these structures may be restricted to a central channel.
直径为25至55埃的已用聚乙烯吡咯烷酮包被的胶体金颗粒被显微注射到变形虫（大变形虫）的基质细胞质中。在注射后1分钟、2分钟、10分钟和24小时的时间间隔，细胞被固定用于电子显微镜观察。24小时后，在细胞核和基质细胞质中均发现了金颗粒，细胞核中的浓度更高。10分钟后细胞核中也存在胶体颗粒，但在此时间间隔，其浓度似乎并不高于基质细胞质中的浓度。注射后1分钟和2分钟，金颗粒几乎完全位于基质细胞质中；然而，单个颗粒经常出现在核膜环内，并特别位于这些结构的中心。结果表明，进入细胞核的至少一些金颗粒穿过核膜环，并且通过这些结构的通道可能限于中央通道。
