胚层

The adhesive capacity of differentiated cells that stably expressed E-cadherin was markedly enhanced. Compact cell connection and multi-layer growth state remained at 19 days. While non-transfected ESCs gradually changed from embryoid bodies into noncohesive cell populations.

稳定表达上皮型钙粘蛋白的分化细胞间黏附能力明显增强，并在19 d时仍能保持致密的细胞连接和多层生长状态，普通胚胎干细胞则由拟胚体结构逐渐分化为松散的细胞群落。

Notch1 is expressed by stem cells resided in the cervical loop epithelium, and Notch signaling pathway play a central role in fate decision of those stem cells. Notch receptors and their ligands are involved in both patterning and cell fate determination during odontogenesis. Moreover, many cell factors, which are closely related with odontogenesis, could regulate expression of Notch receptors or their ligands.

既往研究显示：早在牙齿发育期，Notch1就表达于颈环星网状层的干细胞中，是其保持干细胞性质的重要机制；Notch-Delta信号还与成釉细胞、成牙本质细胞分化有关，被认为是牙齿发育细胞分化多样性的原因之一；另外，目前已明确与牙胚细胞分化有关的生长因子如TGFβ、FGF、BMPs等均可诱导Notch受、配体的表达。

Seeds reniform, slightly compressed, with a fleshy red outer layer; endosperm abundant.

种子肾形，稍压扁，具一个肉质的红色的外部层；胚乳丰富。

In a giving stage after pollination,p53 homologue showed high levels in the antipodal cells,integument,immature endosperm,ovary wall,tracheary elements,and aleurone layer,while c-myc homologue showed low levels in these tissues,only before pollination showed high expression in polar nucleus.

结果发现，在授粉后的一定阶段，在反足细胞、珠被、未成熟的胚乳、子房壁、导管组织和糊粉层中，p53同源基因表达强烈，c-myc同源基因的表达相反，在授粉后的这些组织中基本不表达，而在授粉前的中央细胞的极核中表达水平较高。

Oct4 plays a critical role in maintaining pluripotency of stem cell when it differentiates into a trophectoderm lineage at early stage of mouse embryo.

在早期鼠胚中，只有在ICM变成滋养层阶段，Oct4为维持其全能表型而发挥作用。

GFP fluorescence was visible early at the 2-cell stage and then became stronger in the blastocysts of all three species. However, the distribution of the GFP signals was restricted to the cells of inner cell mass and no fluorescence was detectable in trophectoderm cells.

结果显示：牛Oct-4启动子驱动的GFP基因在3个物种的2-细胞胚胎就已经开始表达，在囊胚期表达加强且只特异表达于内细胞团中，而不表达于滋养层。

Results: Different mineralized layers in different period of development appeared different color variation in the dental germs.

结果：在牙胚矿化过程中，不同时期、不同矿化层呈现不同的颜色变化。

With the assistance of molecular probes for reactive oxygen species, the production and localization of ROS derived from embryo, starch and aleurone layer of maize seeds with different ages were investigated under a laser scanning confocal microscope and a luminescence spectrometer.

摘 要：借助活性氧发光分子探针，利用荧光光谱和激光共聚焦扫描显微技术，在不同年份的玉米种子吸胀早期，对其胚、淀粉和糊粉层细胞活性氧生成进行了定量和亚细胞定位分析。

These were raised underinducing condition to test if any morphology and structure changes. Twenty two Arabidopsismutants had various changes in morphology and anatomical structures. Twenty mutants hadlow germination rate from 10% to 60%, of which 2 had survival rates at 0% and 50%. Fivemutants occurred structure changes in the hypocotyls or stem. One of these lines, namedarris-stem, showed some unique changes: slower growth rate in comparison with the wildtype from germination to florescence; serrated margin of leaf blades, spiral rosette; morebranch in the bottom part of the stem, shorter nodes, twisted stem and branch. There were oneor several arrises along the stem. Across sections of the arrises showed one or several compactcells lumps which were round, made up of several layers of cells, looked like vascular-bundle.

在诱导条件下，这些突变体表现出不同的形态和结构的变化，共有22个表型和结构发生变化。20个突变系发芽率或存活率较低，发芽率由10％—60％，其中2个突变系存活率分别为0％和50％。5个突变系在茎或下胚轴的结构上发生变化，其中一个突变系arris-stem发生如下表型变化：从真叶出现至开花结实的整个生长期，生长速度要明显比野生型拟南芥缓慢；叶缘有明显锯齿，莲座叶呈螺旋状排列；茎的基部有较多侧枝，侧枝间距明显缩短，茎有明显扭曲；突变体茎侧面有1至数条棱形突起，内部存在一至数个排列紧密的细胞团，由多层细胞呈环形排列，细胞壁明显加厚，内部存在管状分子，推测为维管组织。

Cut hearty root vegetables like parsnips, turnips, rutabagas, carrots, and onions into inch-thick chunks and arrange in a single layer on a cookie sheet.

将根部饱满的蔬菜，如防风草，芜菁，芜菁甘蓝，胡萝卜和洋葱切成丁状，将他们摆在胚面片上一层。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。