裂细胞

Tetraploid embryos could be produced by electrofusion at the stage of two-cell embryos, which could develop to blastcysts fellowed by fusion of cytoplasm and nucleus and cleavage in vitro.After fusion of cytoplasm, the DNA methylation levels of the fused embryos was very high as well as two-cell diploid embryos in vivo.Then the embryos was rapiddly demethylated when the nucleus begin to fuse, resulting the lowest DNA methylation levels when the nucleus fused completely.After that, the DNA methylation levels of fused embryos were gradually increased until the blastocysts stage.However, whereas an asymmetric distribution of DNA methylation was established in an vivo-derived blastocysts with a higher methylation level in the inner cell mass than in the trophectoderm, in most vitro-derived tetraploid blastocysts, we can not detect the asymmetric distribution.

结果表明：利用电融合方法制备的小鼠四倍体胚胎在体外培养体系中经历细胞质融合、细胞核融合及细胞继续分裂发育直到囊胚期的过程，在细胞质融合的时候胚胎卵裂球同体内体外培养二倍体胚胎一样，呈现高度甲基化状态；在细胞核开始融合的时候，甲基化水平急速下降，在细胞核完全融合的时候甲基化水平达到最低点；随着胚胎继续分裂，胚胎甲基化水平逐渐增加，在囊胚期甲基化水平最高；但是囊胚期四倍体胚胎内细胞团同滋养层细胞甲基化荧光信号没有差别，这与体内体外培养二倍体囊胚内细胞团细胞甲基化荧光强度高于滋养层细胞甲基化荧光强度不同。

In the normal group, electron microscopy showed normal chondrocytes were oval, and cells and cell membrane were intact. In cytoplasm, there were abundant rough endoplasmic reticulum, dictyosome, and mitochondria with intact nucleus, and even chromatin. In the model group, chondrocytes exhibited obvious pyknosis and their shape was irregular. The areolae around cells disappeared; cell organs in cytoplasm coagulated to flaps which showed electron dense and was uneasy to observe; the shape of nucleus showed irregularity, and caryotin gathered densely.

电镜下正常对照组软骨细胞呈椭圆形，细胞及胞膜完整，包质内可见丰富的粗面内质网、高尔基体、线粒体，细胞核完整，染色质分布均匀；模型对照组软骨细胞明显固缩且外形不规则，细胞周晕消失，胞浆内细胞器凝成高电子密度的片状物不易分辨，细胞核不规则，染色质浓聚，散裂于核中。

Neuroectoderm; neural crest; neural plate; floor plate; neural tube; neuraxis; neuroblasts; neural stem cells; neuroprogenitor cells; stem cells; differentiation; ontogeny; morphogenesis; histogenesis; organogenesis; synaptogenesis; gangliogenesis; embryogenesis; axonogenesis; retinogenesis; gliogenesis; glial progenitor cells; oligodendrocyte progenitor cells; retinal progenitor cells; nerve growth factor; neurotrophic factors; trophic factors; growth factors; neural tube defects; anencephaly; spina bifida; cell migration; neurogenesis; development; developmental stages

神经外胚层；神经脊；神经板；底板；神经管；轴索；成神经细胞；神经干细胞；神经母细胞；干细胞；分化；个体发生；形态发生；组织发生；器官发生；突触发生；神经节发生；胚胎发生；轴突发生；视网膜发生；神经胶质发生；神经胶质祖细胞；少突神经胶质细胞祖细胞；视网膜祖细胞；神经生长因子；神经营养因子；营养因子；生长因素；神经管缺陷；无脑；脊柱裂；细胞迁移；神经发生；发展；发育阶段

Neuroectoderm; neural crest; neural plate; floor plate; neural tube; neuraxis; neurulation; neuroblasts; neural stem cells; neuroprogenitor cells; stem cells; differentiation; ontogeny; morphogenesis; histogenesis; organogenesis; synaptogenesis; gangliogenesis; embryogenesis; axonogenesis; retinogenesis; gliogenesis; glial progenitor cells; oligodendrocyte progenitor cells; retinal progenitor cells; nerve growth factor; neurotrophic factors; trophic factors; growth factors; neural tube defects; anencephaly; spina bifida; neuroblastoma cells; neurogenesis; development; developmental stages

神经外胚层；神经脊；神经板；底板；神经管；轴索；神经胚形成；成神经细胞；神经干细胞；神经母细胞；干细胞；分化；个体发生；形态发生；组织发生；器官发生；突触发生；gangliogenesis；胚胎发生；axonogenesis；retinogenesis；gliogenesis；神经胶质祖细胞；少突神经胶质细胞祖细胞；视网膜祖细胞；神经生长因子；神经营养因子；营养因子；生长因素；神经管故障；无脑；脊柱裂；成神经细胞瘤细胞；神经发生；发展；发展进程

Neuroectoderm; neural crest; neural plate; floor plate; neural tube; neuraxis; neurulation; neuroblasts; stem cells; differentiation; ontogeny; morphogenesis; histogenesis; organogenesis; synaptogenesis; gangliogenesis; embryogenesis; axonogenesis; retinogenesis; gliogenesis; glial progenitor cells; oligodendrocyte progenitor cells; retinal progenitor cells; nerve growth factor; neurotrophic factors; trophic factors; growth factors; neural tube defects; anencephaly; spina bifida; neuroblastoma cells; cell migration; neurogenesis; development; developmental stages

神经外胚层；神经脊；神经板；底板；神经管；轴索；神经胚形成；成神经细胞；干细胞；分化；个体发生；形态发生；组织发生；器官发生；突触发生；gangliogenesis；胚胎发生；axonogenesis；retinogenesis；gliogenesis；神经胶质祖细胞；少突神经胶质细胞祖细胞；视网膜祖细胞；神经生长因子；神经营养因子；营养因子；生长因素；神经管故障；无脑；脊柱裂；成神经细胞瘤细胞；细胞迁移；神经发生；发展；发展进程首页上一页下一页末页共有 22 条记录，本页从第 11 到第 20 条。

Different strains have different reaction to the delay of oviducts in body after animal death. After 10min delay C57BL/6 mouse oocytes have death rate of 56.5%,significantely higher than Kunming mouse (47.6%);Spontaneous activation rates were respectively 13.3% and 46.0%, C57BL/6 were obviously lower than Kunming mouse.4. The oviducts were obtained after being delayed 5min 24h after the mice were injected with hCG. The oocytes were cultured in CZB. About 81.1% occurred spontaneous activation, evidently lower than parthenogenetic rate (96.4%) with SrCl_2. Spontaneous activable oocytes had high cleavage rate(93.2%) and 4-cell rate(87.3%). However, spontaneous activable oocytes had blastula development rate(18.7%) as low as parthenogenetic oocytes by SrCl_2(22.9%).

不同品系小鼠卵母细胞对输卵管在体内滞留产生的反应不同，滞留10min C57BL/6系小鼠卵母细胞死亡率为56.5%，显著高于昆明鼠(47.6%)；自发激活率分别为13.3%和46.0%，C57BL/6系小鼠显著低于昆明鼠。4.hCG后24h体内滞留5min卵母细胞在CZB中培养自发激活率为81.1%，显著低于SrCl_2孤雌激活率(96.4%)；自发激活的卵母细胞有较高的卵裂率(93.2%)和4-cell比率(87.3%)，但囊胚率(18.7%)较低，同卵龄的卵母细胞经SrCl_2孤雌激活囊胚发育率为22.9%，差异不显著。

Neuroectoderm; neural crest; neural plate; floor plate; neural tube; neuraxis; neurulation; neuroblasts; neural stem cells; neuroprogenitor cells; stem cells; differentiation; ontogeny; morphogenesis; histogenesis; organogenesis; synaptogenesis; gangliogenesis; embryogenesis; axonogenesis; retinogenesis; gliogenesis; glial progenitor cells; oligodendrocyte progenitor cells; retinal progenitor cells; nerve growth factor; neurotrophic factors; trophic factors; growth factors; neural tube defects; anencephaly; spina bifida; neuroblastoma cells; neurogenesis; development; developmental stages

神经外胚层；神经脊；神经板；底板；神经管；轴索；神经胚形成；成神经细胞；神经干细胞；神经母细胞；干细胞；分化；个体发生；形态发生；组织发生；器官发生；突触发生；神经节发生；胚胎发生；轴突发生；视网膜发生；神经胶质发生；神经胶质祖细胞；少突神经胶质细胞祖细胞；视网膜祖细胞；神经生长因子；神经营养因子；营养因子；生长因素；神经管缺陷；无脑；脊柱裂；成神经细胞瘤细胞；神经发生；发展；发育阶段

Neuroectoderm; neural crest; neural plate; floor plate; neural tube; neuraxis; neurulation; neuroblasts; stem cells; differentiation; ontogeny; morphogenesis; histogenesis; organogenesis; synaptogenesis; gangliogenesis; embryogenesis; axonogenesis; retinogenesis; gliogenesis; glial progenitor cells; oligodendrocyte progenitor cells; retinal progenitor cells; nerve growth factor; neurotrophic factors; trophic factors; growth factors; neural tube defects; anencephaly; spina bifida; neuroblastoma cells; cell migration; neurogenesis; development; developmental stages

神经外胚层；神经脊；神经板；底板；神经管；轴索；神经胚形成；成神经细胞；干细胞；分化；个体发生；形态发生；组织发生；器官发生；突触发生；gangliogenesis；胚胎发生；axonogenesis；retinogenesis；gliogenesis；神经胶质祖细胞；少突神经胶质细胞祖细胞；视网膜祖细胞；神经生长因子；神经营养因子；营养因子；生长因素；神经管故障；无脑；脊柱裂；成神经细胞瘤细胞；细胞迁移；神经发生；发展；发展进程下一页末页共有 23 条记录，本页从第 1 到第 10 条。

It is evident that the plerocercoids parasitize mainly in the subcutaneous tissues and muscles of mice, and mice experimentally infected with plerocercoids show different degree of histopathological changes.

小鼠感染裂头蚴后，多组织器官有裂头蚴寄生，其中以皮下肌肉处多见。裂头蚴寄生可引起组织不同程度的增生、变性、坏死，组织结构破坏及大量炎症细胞浸润等病理变化。

The results show that the secretory ducts are schizogenous cavity which are only distributed in the stem and the leaf.The initial of the secretory duct drives from the ground meristem.

结果表明，分泌道为裂生腔隙，只分布于茎和叶中；分泌道原始细胞起源于基本分生组织；分泌道原始细胞团裂隙的扩大靠鞘细胞的插入和上皮细胞自身的切向伸长；成熟的分泌道呈圆形或椭圆形，由一层上皮细胞和其外的1 ～2 层鞘细胞包被。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。