胚细胞

These cells were also identified with alkaline phosphatase staining and Alizarin red staining of calcified nodules.

结果：①人胚成骨细胞原代和传代培养的生长特征：原代培养至第5天，骨块边缘出现零散的细胞，这些细胞的形态主要为梭形、三角形或多边形。

Comparisons between the cell lines were made on the basis of time to observed cytopathic effects, ultra structure changes, titer in 50% tissue culture infectious doses, and the alterant distribution of DNA content in cell cycle. The results showed that, under identical conditions, various degrees of CPE could be found in the Hep-3B, A549 and NIH 3T3 36h post infection of BTV-10, while there was no CPE could be observed in HEL.

随后在对BTV-10体外感染特性的研究中，我们在相同条件下，将该病毒接种于1株原代人胚肺成纤维细胞(Human embryonic lung fibroblast cells，HEL)和3株传代细胞株：人肝癌细胞(Human hepatic carcinoma 3B cells，Hep-3B)；人肺腺癌细胞(Human lung carcinoma A549 cells，A549)；鼠正常成纤维细胞(Normal mouse fibroblastscells，NIH 3T3)。

The results suggest that Smad4,one of the intracellular downstream molecules of TGF-β superfamily,and an inductive signal mediating epithelial-mesenchymal interaction,may regulate the differentiation of ameloblast and odontoblast cells,and modulate dentinogenesis and amelogenesis.

结论首次观察到Smad4信号分子在人牙胚发育过程中的表达，Smad4作为TGF-β超家族细胞内信号分子，可能参与上皮间充质的相互作用，同时也参与成釉细胞和成牙本质细胞的分化以及牙釉质和牙本质的形成。

In contrast with the rapid nucleus degradation, cell organelles in cytoplasm, such as rough endoplasmic reticulum, amyloplast, and mitochondrion, maintained their metabolic functions for a longer time.

在核衰退的同时，其胞质中的粗面内质网、淀粉质体和线粒体等细胞器具有正常的代谢功能，细胞仍在合成并积累营养物质，淀粉胚乳细胞一边衰退一边行使其功能，直至死亡。

In addition, using RT-PCR to detect expression of centrin homogene during Urechis unicinctus spermatid deferentiation and early embryonic development. The result revealed that (1) expression of HsCEN1 homogene is present during spermatid defferentiation including spermtid and sperm, but not in adult tissues including body wall tissue,intestinal mucous memberane cells and cell in coelom succus;(2) expression of HsCEN1 homogene is not present in unfertilized oocytes but present in that of released polar bodies after fertilization and parthenogenesis oocytes treated with A23187;(3) expression of HsCEN1 homogene is present during early embryonic development including two-cell stage,multicell stage,gastrula to trochophora.

我们还用RT-PCR方法检测了Centrin同源基因在单环刺螠精子分化过程和早期胚胎发育过程的表达，结果显示：在单环刺螠精子发生过程中的精细胞、精子团、精子中都有表达，而在成体的体壁组织、消化道组织、体腔球中则没有表达；在未受精卵中没有表达，而在受精后释放极体的受精卵和经A23187孤雌激活的卵中则有表达；在单环刺螠的早期发育过程——二细胞胚胎、多细胞胚胎、原肠胚、早期担轮幼虫——中都有表达。

Identification of these cells: Over 90% cells isolated from human fetal calvaria were stained positively for both alkaline phosphatase and Alizarin red.

采用酶消化后植块的改良植块培养法可在较短时间内获得大量成骨细胞，这些细胞具有典型的成骨细胞形态和功能，是一种较好的分离培养人胚成骨细胞的方法。

Generally we think muscular histogenesis has many steps of biology, including foetal mesoderm merotomy; myoblast shapes in arthromera; myoblast can form muscular tissue to move to limbs; the proliferation of sarcoblast can increase cells\'quatity.

一般认为，肌组织发生是一多步骤的生物学过程，包括胚胎中胚层的分节；成肌细胞在体节形成；成肌细胞向四肢迁移形成肌组织；成肌细胞增殖以增加细胞数量。

Abstract〕 objective: To study the effects of retinoic acid on the proliferation and apoptosis of undifferentiated ectomesenchymal cells derived from facial primordia of mouse fetus.

摘要〕 目的：研究维甲酸处理未分化外胚间充质细胞后，细胞增殖和细胞凋亡的变化，探讨细胞增殖、凋亡与维甲酸之间的关系。

Histologically,the activity of cell division in scutellar epithelium and callus cluster derived from it was higher in cultivar Aikoku than Moritawase.Moreover different types of differentiation in the epithelial callus were observed,the rootlike structures and globular cell clusters with epidermislike structure were found in the calli of cultivar Moritawase and Aikoku respectively.

组织学的观察表明，Aikoku的种胚盾片上皮组织以及由上皮细胞起源的愈伤组织的细胞分裂活性高于Moritawase；而且在上述2个品种中还观察到不同的细胞分化类型，在Aikoku的愈伤组织中观察到了带有表皮状结构的圆形细胞块，而在Moritawase的愈伤组织中却观察到了根状结构。

Results: Embryoid bodies grew well in Collagen Gel, the differentiated cells grew into the gel gradually; electronmicroscope showed that some induced cells were rich in Golgi's bodies and endoplasmic reticulums, a few secretory granules were also visible, which was similar to human adult thyrocyte.

结果 拟胚体在鼠尾胶原上生长状态良好，分化细胞贴壁后逐渐陷入鼠尾胶原；电镜下诱导细胞高尔基体、内质网丰富，部分诱导细胞胞质内见不典型分泌颗粒，与人成体甲状腺细胞超微结构类似。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。