牙发育异常

ABSTRACT Agenesis of one or more teeth constitutes one of the most common developmental anomalies in man.

牙齿的发育不全是一种人类常见的发育异常，先天缺牙是牙齿发育异常的表现之一，可伴随遗传性的综合征出现，也可能是单独的症状以散发病例或家系遗。。。

Tooth agenesis is a common tooth dysplasia.

先天缺牙是比较常见的牙齿发育异常疾病。

Tooth agenesis also named teeth number deficiency. It happens in tooth forming process or earlier period of tooth germ development.

先天缺牙又称牙齿数目不足，是在牙胚形成过程中或牙胚发育的早期，即牙蕾形成期的异常。

Supernumerary teeth is one of the dysplasia that the number of the teeth are more than physical number.

多生牙是一种牙齿数目多于人体生理牙数的牙齿发育异常，数目一般为1～2颗，3颗以上者甚为少见，偶见多颗多生牙报道。

Hypohidrosis ectodermal dysplasia is a rare congenital disorder that results in abnormalities in the structures of ectodermal origin tissues, such as teeth, eccrine sweat glands, hair and nails.

少汗型外胚层发育不良症是一种罕见的起源于外胚层组织，如牙、汗腺、毛发等发育异常的遗传性疾病。

On the termination date, the cultured explants were all examined by Western blot, HE and transmission electron microscope. Our results showed that after 12-days in culture, the cultivation treated with AS-ODN reduced the synthesis of AMBN and had a deformed dental cusp with thinner enamel matrix. Ultrastructure analyses showed that there was hardly any cisternae of the rough endoplasmic reticulum in the ameloblasts at the tip of the cusp of AS-ODN treatedexplants. However, on average the enamel matrix was thinner compared with that in the control group. Furthermore, the collagen fibers in extracellular matrix were found disorganized. These findings seemed to provide a direct experimental evidence that tended to indicate that the arrested AMBN translation in cultured tooth germs might result in the delay of the tooth development.

经用Western蛋白印迹检测表明，所设计的反义核酸对AMBN InRNA具有良好的封闭效果并成功阻断了牙胚对AMBN的表达；在缺乏AMBN情况下，与对照组相比，实验组牙胚在体外可以继续生长发育至钟状晚期，出现成釉细胞和成牙本质细胞的分化，成釉细胞可以分化成为分泌期型成釉细胞，胞浆中缺少合成蛋白质所必需的粗面内质网和高尔基氏体，缺乏溶酶体，表明对蛋白合成和脚的能力降低；实验组牙胚有牙尖形成和基质分泌，但牙尖形态异常，基质形成减少，牙尖周围基质最厚处为O.6卜m，明显薄于对照组的5.spin，基质中胶原纤维粗细不等，排列稀疏， 3 第四军医大学硕士学位论文未见钙化现象，充分证明了AMBN在牙胚发育中参与釉质基质形成和矿化过程，影响胶原纤维和牙本质基质的合成，促进成釉细胞对蛋白质的合成和釉质基质蛋白降解。

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。