Implication of C-5, C-6 unsaturation as a key structural factor in steroidal alkaloid-induced mammalian teratogenesis

Hamster teratogenicity induced upon oral administration of steroidal alkaloids (solanidanes, spirosolanes and jervanes) appears to relate very closely to the presence or absence of C-5, C-6 unsaturation in the alkaloid, which may be more important than molecular configuration at C-22 and placement of the nitrogen atom with regard to the plane of the steroid.     

面部软组织三维有限元建模和变换

为了实现在临床上快速地为病人建立个体化有限元模型用于正畸治疗的术前预测,研宄首先在正常领型志愿者A的CT数据的基础上建立一含包含度朕、肌肉和脂肪的通用唇面部软纽织三维有限元模型。然后通过选取的面部标志点,使用径向基函数（Radial Base Function,RBF）插值法把通用模型变换成志愿者B的唇面部模型而实现通用模型的含体化。结果显示志愿者B的个体化模型和其CT数据在唇面部区域的平均误差在0．47mm左右,而且具有较好的相似度。     

Effects of retinoic acid on embryonic development of mice in culture

Summary The effects of all-trans-retinoic acid (RA) (tretinoin) on the craniofacial development of mouse embryos were examined using whole embryo culture. In day 8 embryos cultured for 48 h, embryonic growth was inhibited concentration-dependently by all-trans-RA treatment. Most of the treated embryos exhibited hypoplasia of the primary palatal processes and a reduction in the development of the first viscreral arches. In day 10 embryos cultured for 48 h, although embryonic growth was not inhibited at any concentrations of all-trans-RA, median cleft lip (93%), hypoplasia of the primary palatal processes (37%) and limb reduction deformities (48%) occurred commonly. Furthermore, RA treatment greatly reduced the size of the secondary palatal processes. The incorporation of³H-thymidine in the treated maxillary processes was decreased to 65% of the control value at 1.0×10^–7 M alltrans-RA. These findings indicate that all-trans-RA is teratogenic in mouse whole embryo culture.     

江西省畲族人体头面部微机测量研究

目的研究江西省畲族人体头面部器官测量数据。方法采用国内研制的人体头面部摄像-计算机测量系统,按照随机抽样原则选择江西省吉安市200名正常的畲族成人进行了头面部器官测量研究。结果得出了该民族成年男女两性头面部16个测量项目和13个头面部指数的资料,发现该民族成年男女两性头面部除容貌额高所测值男女两性无差异外,其余各项所测值男女两性间差异有显著性,并以4个头面部指数对男女两性头型、面型分别进行了分类、对比。结论该研究成果对人类学、民族学、医学和工业等学科具有重要的参考价值。     

颅面生长的控制理论

颅面生长的控制理论是颅面生长发育理论的重要组成部分。本文综述了颅面生长的遗传控制理论,功能基质假说和伺服系统理论等的基本内容,介绍了各种理论的特点和局限性,阐述了颅内生长控制理论从遗传到渐成影响的认识变化,并应用各种理论解释了颅面正常生长发育深入研究遗传的渐成因素对因素对颅面生长控制的作用。     

分区变形与多重约束结合的面皮层次点对应方法

针对颅面统计复原中基于面貌形态几何特征建立三维面皮间生理点对应关系的难题,提出几何模板分区变形与多重约束结合的三维面皮层次点对应方法(HCRDM).该方法根据人脸生理结构特征点定义一套五官分区几何模板,以实现面皮分区半自动化;根据特征点的严格对应关系,利用径向基函数对样本面皮各分区变形;为近似重合的各分区建立体素模型,逐次选取特征显著的模板顶点作为待对应点,利用模板顶点间局部相对位置几何约束确定样本分区中对应点候选集;根据局部几何特征加权距离确定最优对应点;结合几何约束与微分特征距离约束实现边界区域点对应.实验结果表明,HCRDM较已有的三维面皮点对应算法准确率提高了10％以上.