担轮幼虫

至受精后48h，诱导组滞育的原肠胚和担轮幼虫比例显著高于对照组。

The arrested gastrulae and trochophore were found significantly higher in treated groups than that in controls during 48h post-fertilization .

随着照射时间的增加，受精率和D形幼虫发生率明显下降。而照射时间超过20s，担轮幼虫存活率逐渐提高，表明Hertwig效应的存在。

The rates of the fertilization and the development of D-shaped larvae decreased with increasing irradiation time , while the survival rate of trochophore larvae became improved at UV exposure longer than 20 s , suggesting the presence of a " Hertwig effect " in the gynogenesis of C.

在担轮幼虫期，中央的内脏团原基呈NSE极强阳性或POD强阳性，其余细胞则呈NSE强阳性或POD阳性。

The cells in the centre of the trochophore showed very strong positive NSE and strong positive POD .

单环刺螠虫受精后卵子先后排放第一、二极体，经螺旋型卵裂后生成腔囊胚，囊胚经内陷形成原肠胚，胚体于受精后24h孵化，形成担轮幼虫。

After artificial fertilization , the first and second polar body was released from the egg . The blastula was formed by spiral cleavage . The gastrula , which was formed by invagination , was hatched at 24h pf ( post-fertilization ) .

担轮幼虫的原生殖细胞和面盘上方少数细胞中可见Cf-boule的高水平表达，但在随后的发育中消失。

A high level expression of Cf-boule was observed in the putative PGCs and several cells above velum in trochophore , and disappeared in following stages .

表达Cf-vasa的原生殖细胞形成于原肠胚时期，在担轮幼虫中对称分布于口凹两侧，并随幼虫发育迁移至D型幼虫末端后，继续沿边缘向腹面迁移。

The putative PGCs with Cf-vasa expression form in gastrula stage , and are located symmetrically at both sides of the stomodeum in trochophore . These cells subsequently migrate to the posterior pole of D-shaped larva and then migrate towards abdomen .

以宽壳全海笋担轮幼虫为材料，采用热滴片法进行染色体核型分析。

The chromosome karyotype of Barnea dilatata was studied on its trochophore by means of hot-dropping method .