髓鞘形成

Extraembryonic /ex·tra·em·bry·on·ic/胚外的 adj.Definition : Located outside of the embryonic body. External to the embryo proper, as the extraembryonic coelom or extraembryonic membranes.

部分神经细胞在轴突外围会被一些我们称为髓鞘细胞的细胞包围住，髓鞘细胞可使得神经细胞的冲动传递速度加快，因而形成跳跃式传递。

Results: electronic microscope showed that in prednisone group heterochromatin increased in some cells, entoblast was not obvious in some cells, fat drops were small and few, mitochondria vacuole were common, and myelin figure was found in smooth endoplamic reticulum. the ultrastructure in yc group was almost normal and megamitochondrion formation was common. a large amount of fat drops were found in cytoplasm in gw group and little improvement was found compared with that in prednisone group.

结果： 电镜结果显示：激素组个别细胞异染色质增多，核仁不明显，脂滴显著变小变少，线粒体空泡化常见，有滑面内质网髓鞘样结构形成；养阴组电镜结构基本正常，其特征是细胞内有较多的巨大线粒体形成；桂附组较激素组改善不明显，其特征是胞质内可见大量脂滴。

And wide gaps appeared between axon and myelin sheath, and between layers of myelin shea.

可见轴突与髓鞘间及髓鞘板层间形成宽大的裂隙。

And large gaps were seen between axon and myelin sheath and intermyelin sheath layers.

可见轴突与髓鞘间及髓鞘板层间形成宽大的裂隙。

But, deep myelination, or the erosion of the protective sheath around the axons of neurons, may not be reversible if B-12 deficiency is severe or long-term, she said.

但是，她说，如果长期严重缺乏B12，一旦髓鞘已经形成，或神经原轴突周围的保护性鞘已受侵蚀就是不可逆的了。

Objective to evaluate the functional recovery of acute spinal cord injuried rats treated with exogenous wnt-3a signal protein administration and to explore its mechanism.methods moderate spinal cord contusion injury was made in 40 adult sprague dawley rats at t10.twenty rats served as contusion controls(group 1).twenty rats were treated with wnt-3a for three days after injury (group 2).the functional recovery of the rats was observed through basso,beattie,bresnahan open field locomotor score.rats were killed at 14 or 28 days after injury,then spinal cords were removed for histopathological examinations,and the expression of the bromodeoxyuridine plus neural cell markers was stained with immunohistochemical method.results rats of two groups receiving a contusive injury recovered substantial function within 1 week.by 28 days,rats in groups 2 scored 7.0 points better on the bbb scores than rats in group 1 group 2=16.94,after 28 days vs.

目的 研究外源性wnt-3a信号蛋白对脊髓损伤的修复作用，并探讨其作用机制。方法取40只成年雌性sd大鼠在t10节段制备适度脊髓挫伤模型。随机从中取20只为损伤对照组(group 1)，另外20只为损伤治疗组(group 2)。脊髓损伤3天后用wnt-3a蛋白治疗。这些大鼠的功能恢复通过basso、beattie、bresnahan开放视野运动评分来观察。这些大鼠分批在损伤后14天或28天被处死，取出损伤节段脊髓用来组织病理学检查，同时用5-溴脱氧尿嘧啶核苷和神经细胞标记物进行免疫组化染色。结果两组大鼠在伤后一周运动功能有明显的恢复。不过，到损伤后28天，我们观察发现，损伤治疗组中的大鼠bbb评分比损伤对照组中的评分高出7.0分左右(group 2∶16.94±1.18，group 1∶9.89±1.29；p.05)，光镜和电镜检查发现wnt-3a蛋白对髓鞘形成和轴突再生有一定的修复效果。

Schwannomas are typically benign, slow growing tumors that arise from the schwann cells, which envelop and myelinate cranial, spinal, and peripheral nerves.

神经鞘瘤是典型的良性、缓慢生长的肿瘤，起源于许旺细胞，包绕并形成颅内、脊髓以及周围神经髓鞘。

The myelinization of cerebellar white matter,middle cerebellar peduncles,anterior limb of internal capsule,splenium and genu of corpus callosum,centrum semiovale,the white matter in parietal-occipital area and frontal-temporal area were documented at birth to 5,2～4,3～7,3～5,4～7,2～7,3～9 and 4～12 months old,respectively.

髓鞘形成至成熟时间：小脑上下脚、桥脑背侧、丘脑腹外侧和内囊后肢后部出生时已成熟，小脑自出生至5个月，小脑中脚2～4个月，内囊前肢3～7个月，胼胝体后部、膝部分别是3～5个月、4～7个月，半卵圆中心2～7个月，枕顶叶白质3～9个月，额颞叶白质4～12个月。

Lipid peroxidation would cause the deficiency of myelinogenesis, Dysfunction of synaptic conduction and developmental anomaly of nerve cell if the deficiency of completely.

当硒缺乏时，硒蛋白活性降低，清除H2O2能力减弱，脂质过氧化导致髓鞘形成不良，突触传导障碍，神经元发育异常，造成严重的脑功能紊乱。

METHODS: We performed neurological examination, neurophysiological, neuroimaging, and neuropathological studies on sural nerve biopsy in 10 hypomyelination and congenital cataract patients from 5 unrelated families.

我们进行神经系统检查、神经生理学、神经影像学和腓肠神经活检的神经病理学研究，这些是对来自于5个不相关家庭的10例先天性白内障和神经髓鞘形成不良患者进行的检查。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。