Bosco L, Filoni S, Cioni C, Bernardini S
J Exp Zool. 1986 Dec;240(3):401-7. doi: 10.1002/jez.1402400315.
Outer cornea of lensectomized Xenopus laevis tadpoles at state 50 (according to Nieuwkoop, P.D. and Faber, J., ('56) Normal Table of Xenopus laevis, Daudin, North-Holland, Amsterdam, pp. 1-243) was removed 3, 7 and 10 days after lensectomy and implanted between the outer and the inner cornea of larvae of the same species at stage 51-52. In these conditions, the implanted outer cornea remained isolated from the retinal factor of the vitreous chamber, although it received the nutritional factors normally reaching the outer cornea. Results show that lens-forming transformation process of the outer cornea is arrested, and lens-forming structures undergo regression at speed which increases with increasing precocity of the stage of lens-forming transformation undergone by the implanted cornea. These data suggest that the process of lens-forming transformation is not a single-step process, but a sequence of interactions extending over a long period of time requiring the continuous presence of the retinal factor in the vitreous chamber until complete differentiation of the lens is achieved.
在第50期（根据尼乌科普，P.D.和法伯，J.，（1956年）《非洲爪蟾正常发育表》，多丹，北荷兰，阿姆斯特丹，第1 - 243页）对非洲爪蟾蝌蚪进行晶状体切除术后3天、7天和10天，切除其角膜外层，并将其植入处于第51 - 52期的同物种幼虫的外层角膜和内层角膜之间。在这些条件下，植入的角膜外层与玻璃体腔的视网膜因子隔离，尽管它接受了通常到达角膜外层的营养因子。结果表明，角膜外层的晶状体形成转化过程被阻断，并且晶状体形成结构以与植入角膜所经历的晶状体形成转化阶段的早熟程度增加而增加的速度发生退化。这些数据表明，晶状体形成转化过程不是一个单步过程，而是一系列长时间的相互作用，需要玻璃体腔中持续存在视网膜因子，直到晶状体完全分化。
