胚胎发育

（1）Cadmium can enter embryo by permeating placenta barrier and enter brain partly and oosperm can not develop as embryo in the high dose group.（2）The decreasing of some neural transmitter and capacity of anti-oxidation are related to the content and contribution of zinc in embryoes.

（1）镉可透过胎盘屏障和部分透过血脑屏障，高镉可致受精卵不能发育为胚胎；（2）母鼠染镉可致胎鼠脑组织5-HT合成减少，抗氧化能力减弱；这些改变与锌的含量和分布改变有关。

The aim of this study was to analyze the relative expression patterns of mRNA for IGFs in different development stage of preimplanted ovine embryos by using reverse transcription-polymerase chain reaction.

本研究主要在mRNA水平上检测了IGFs在绵羊植入前不同发育阶段胚胎中的表达规律。

Most of them probablyoriginated from the zygote,and minority do from early parthenogenesis.

这些胚胎多数可能是经过受精发育而来的，极少数可能来自早期的单性生殖。

We observed the ultrastructure of cerebral cortex of E18 fetal rat under electron microscope. Lower differentiating neurons lack processes and no synapse between the perikaryon and processes of other neurons.

从胚胎期出现开始到生后相当一段时间内，大脑皮质处于分化发育过程中，可将之分作不同的阶段。

Constant embryonic tooth development began in the first 4 weeks to 9 months to form, the lower total of 28 permanent tooth germ.

恒牙胚的发育始于胚胎第4周，至第9个月形成上、下颌共28个恒牙牙胚。

After the establishmen of implantation,endometrial stromal cells begin to undergo decidualization for the subsequent embryo development and placentation.

在啮齿类动物，着床过程启动后，子宫内膜基质细胞发生广泛的蜕膜化，为接下来的胚胎及胎盘发育做准备。

The factors affecting the seed-set rate ofintersubspecific hybrids include embryo sac sterility,pollen sterility,anther dehiscence and non-synchronization of male and female sexual organsdevelopment in the same spikelet.

对水稻亚种间杂种及其稳定的多胚品系SB-1进行了细胞学、胚胎学和遗传学研究，主要结果如下：1、影响杂种低结实率的因素包括胚囊败育、花粉败育、花药不开裂和雌雄性器官发育进程不一致。

In general, those investment diversities are the results of interactions of many biological traits to meet embryo and nestling development under the predation pressure and interspecies competition.

总之，如此不同的投资差异是在捕食压力和种间竞争作用下以及亲鸟为满足鸟卵胚胎和雏鸟迅速生长发育的必要条件下，各种生物学特征协调的结果。

MethodsEarly embryos at different stages and uterus of the non-pregnant, and pregnant uterus of 1 to 8 days pseudopregnancy in mice were obtained.

方法取小鼠早期胚胎、动情期未孕、真孕及假孕1～8d小鼠子宫，利用免疫组织化学染色及图像分析法，检测p38MAPK在不同发育阶段早胚及围植入期子宫内膜中的表达和变化规律。

But the expression of two genes was high and had obvious rhythmicity under 25LL and 20LD.In a word,after embryo nervous system has grown, the B.mori can strengthen the ability to perceive the illumination and temperature outside.

说明胚胎神经系统发育后，能够增强对外界光照和温度的感知能力，提高per基因和tim基因对授时因子的敏感性，而这两个基因对光照和温度的反应存在差异。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。