原肠

During segmentation,GFP was detected in the notochord but not in the foor plate.

GFP在原肠作用期就开始表达，主要发生在中轴下胚层中；在体节形成期，GFP在脊索细胞中表达，但未发现在神经底板细胞中表达。

This suggests that CaHIRA plays a role in the early embryo development and the late stages. The different expression characters of hira gene in these fish species may be related to the different reproduction models. The research on Drosophila has indicated hira gene related to sperm nucleus decondensation during fertilization. The high expression of hira gene before fertilization is prepared for the sperm nucleus decondensation and the formation of male prenucleus because colored crucian carp is bisexual reproduction. However, the sperm nucleus is not decondensated during the fertilization and is only to activate egg nucleus in gynogenetic gibel carp.

在彩鲫中，从未受精卵到胚胎发育的各个时期均可检测到表达，但表达量发生明显变化，受精后表达量迅速下降，直到原肠胚期表达量有所上升，并一直保持到出苗。hira基因在两亲缘种成熟卵子受精前后表达情况不同，可能与两种鱼不同的生殖方式有关。

In this paper, we studied M. meretrix ferritin, cathepsin B and caspase genes, which are involved in clam larval shell formation, nutrition, metabolism and apoptosis, respectively. We have cloned the three genes, investigated the temporal and spatial expression profile both at gene and protein level in trochophore (L1), D-veliger (L2), pediveliger (L3) and postlarvae (L4). The potential roles of these proteins were analyzed with specific inhibitors during larval development. Firstly, embryos were found developed into trochophore-like larvae with no shell if cultured at gastrula stage in artificial seawater without iron. Shell-like structures were formed only in the presence of iron. The larvae which had been transferred at L1 stage into ASW developed normal shell. This indicated that iron and iron associated protein are important for larval shell formation. The EST sequence which is homologous with ferritin, which is a principal iron metabolic protein, was selected from the M. meretrix cDNA library. The full-length of ferritin subunit cDNA was cloned by RACE. The results of real-time PCR revealed that the MmeFer mRNA expression changed before and after the larval shell formation.

本论文以文蛤幼虫为研究对象，分别对文蛤幼虫发育过程中贝壳形成相关的铁蛋白、营养及变态相关的组织蛋白酶B及变态过程中细胞凋亡相关的caspase三个基因进行了克隆，分析了基因及编码蛋白在担轮幼虫期(L1)、D形幼虫期(L2)、壳顶幼虫期(L3)和稚贝期(L4)的时空表达特征，解析了其可能的功能，并研究了相应酶类的特异性抑制剂作用对幼虫发育过程的影响，进行了目标蛋白的功能验证，详述如下：研究结果显示，在文蛤胚胎发育到原肠胚时放入不含铁离子的人工海水中培养，发育成无壳的畸形，随着人工海水中铁离子添加浓度的升高，幼虫长出壳状组织接近正常状态；而发育到L1期幼虫放入不含铁离子的人工海水中培养却可以发育出正常的壳，推测铁和铁代谢相关蛋白在幼虫贝壳初始形成有重要的作用。

We propose that the noncell-autonomous effects of Spemann's organizer on dorsoventral patterning are executed in part by diffusible signals that directly bind to and neutralize ventral BMPs during gastrulation.

我们提出，施佩曼组织器对背腹式的非细胞自发功能，有部分是通过原肠胚形成过程中，直接结合和抵消腹部BMP的扩散性信号所发挥的。

A variation in gastrulation, involving the movement of cells into endodermal and mesodermal positions through the thickened primitive streak, arose in reptiles and can still be seen in bird and mammalian embryos, lending support

密实的原肠胚通过细胞运动进入内胚层和中胚层，爬虫，鸟，哺乳动物的胚胎都如此。因此提出这样的理论，鸟类和哺乳动物是由爬虫进化而来的。

But soon some of the cells in the gastrula become specialized, a division of labor has set in among the cells which soon deprives them of the capacity to change their own structure and function back to the original state.

但一些细胞在原肠胚很快成为专门的，工作的分配已经设置在细胞之中，细胞很快剥夺他们自己的能力改变他们自己的结构和作用回到原始的状态。

The infolding of a portion of the outer layer of a blastula in the formation of a gastrula.

外胚层囊胚的外层，在原肠胚形成之后生后外胚层组织

Suppression subtractive hybridization cDNA plasmid libraries were constructed between gastrula embryos and tail bud embryos in gynogenetic gibel carp.

构建了雌核发育银鲫原肠期胚胎和尾芽期胚胎间的抑制性差减杂交cDNA质粒文库。

The distribution of NSE and POD were relatively even in the embryo from the oocyte to the gastrula and the embryo showed very strong positive NSE and positive POD.

从卵细胞到原肠胚均呈比较均一的NSE强阳性或POD阳性。

Sequencing analysis and database searches indicated that there were 19 known genes and 31 unknown cDNA fragments in the sequenced 72 dot blot positive clones specific for gastrula embryos,and 52 known genes and 37 unknown cDNA fragments in the sequenced 98 dot blot positive clones specific for tail bud embryos.

测序和基因数据库比对结果表明，72个原肠期斑点杂交阳性克隆中，包括19个已知基因的cDNA片段和31个没有同源性的cDNA片段；98个尾芽期斑点杂交阳性克隆中，包括52个已知基因的cDNA片段和37个没有同源性的cDNA片段。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。