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关键词： Cytokines   Animals   Carrier Proteins   Fibroblast Growth Factor 2   Heparitin Sulfate   In Vitro   Lung   histology   Mice   Mice   Inbred ICR   Microscopy   Phase-Contrast   Morphogenesis   Organ Culture Techniques   Polysaccharide-Lyases   Proteoglycans   Research Support   Non-U.S. Gov't  

摘要： In vitro development of embryonic mouse lung explants was hindered by digestion with heparitinase, which removed about 40% of [S-35] sulfate-labeled heparan sulfate synthesized. The enzyme-treated explants were inhibited in branching morphogenesis and the mesenchymal tissue was thin. Addition of basic fibroblast growth factor (bFGF), a typical heparin-binding growth factor, restored the inhibition caused by heparitinase in branching morphogenesis. Addition of midkine (MK), another heparin-binding growth factor, showed a weak effect on branching morphogenesis, but exhibited an effect in restoring development of mesenchymal tis sue. These data together with the distribution of the factors indicate that both are involved in development of the lung. Heparitinase-treated explants can be useful models for evaluating roles played by various heparin-binding growth factors.

关键词： epithelium   mesenchyme   morphogenesis   submandibular gland   tissue interactions  

摘要： Epithelial tissues in various organ rudiments undergo extensive shape changes during their development. The processes of epithelial shape change are controlled by tissue interactions with the surrounding mesenchyme which is kept in direct contact with the epithelium. One of the organs which has been extensively studied is the mouse embryonic submandibular gland, whose epithelium shows the characteristic branching morphogenesis beginning with the formation of narrow and deep clefts as well as changes in tissue organization. Various molecules in the mesenchyme, including growth factors and extracellular matrix components, affect changes of epithelial shape and tissue organization. Also, mesenchymal tissue exhibits dynamic properties such as directional movements in groups and rearrangement of collagen fibers coupled with force-generation by mesenchymal cells. The epithelium, during early branching morphogenesis, makes a cell mass where cell-cell adhesion systems are less developed. Such properties of both the mesenchyme and epithelium are significant for considering how clefts, which first appear as unstable tiny indentations on epithelial surfaces, are formed and stabilized.

关键词： antibody   cathepsin-L   gastrulation   Xenopus embryos  

摘要： An antibody against cathepsin L-like protease (AACLP) was injected into one cell of 2-celled Xenopus embryos. The blastopores of AACLP-injected embryos either did not invaginate or failed to complete invagination. As a result of this failure to complete gastrulation, the body axes could not form normally and tail bud stage embryos were bent dorsally. Embryos injected with a control antibody (CA) developed normally through the tadpole stage. Mesodermal induction was not inhibited in embryos exhibiting this AACLP-induced gastrulation defect, but the mesodermal structure of these embryos was organized incorrectly due to the defective gastrulation during the early stages.

关键词： 胚胎   脊髓移植   运动功能恢复   运动诱发电位  

摘要： 采用成年大鼠脊髓半切洞损伤模型，移植胚胎大鼠脊髓组织，术后进行联合行为计分和运动诱发电位检查。结果，术后１周、２周和４周，移植组联合行为计分分别为４７±３．１２分、２５±２．７８分和１４±２．８９分，与对照组的８６±４．５６分、６７±４．３４分和５３±４．６２分比较相差非常显著（Ｐ＜０．０１），说明移植组神经功能恢复明显优于对照组；术后１２周，移植组联合行为计分为１１±２．２６，优于对照组的３５±４．１２（Ｐ＜０．０５）。术后１周，移植组运动诱发电位波幅及峰潜伏时已有一定程度的恢复，对照组无明显好转趋势；术后２～１２周，移植组的运动诱发电位早期反应Ｐ１、Ｎ１峰潜伏时的恢复优于对照组（Ｐ＜０．０５）。上述结果提示，胚胎脊髓移植能促进成年受体损伤脊髓的运动功能修复。

关键词： 医学教育   医学专业课   医学院校学生   部分相关系数   基础课   算术平均值   武警医学院   本科生   组织胚胎   基础化学  

摘要： 目前,国内外的医学院校均把化学作为基础课来教授。尽管如此,化学在医学中究竟占有什么位置,它与医学有着怎样的关系等问题一直困扰着医学院校的学生,甚至有些化学教师本身也怀疑化学在医学院校学生将来的工作及科研中的作用。有些学员毕业工作一段时间后,很诚恳地告诉我们,说化学在他们的工作中一点也用不上,言外之意。

关键词： 肾上腺皮质移植   移植   支气管痉挛   哮喘   治疗  

摘要： 采用胚胎肾上腺皮质组织移植治疗154例慢性支气管哮喘息者，移植后随访1年以上。结果临床治愈21例（13．6％），显效68例（44．2％），有效37例（24％），总有效率81．8％。移植术后患者多感体力增加，上呼吸道感染减少，血清皮质醇较移植前上升（P＜0．05）；肺通气功能较移植前有明显改善（P＜0．05）；移植后血IgG、lgE、嗜酸粒细胞计数较移植前明显降低；血压、体重、血糖及血清电解质均无明显变化（P＜0．05）、此种移植手术操作简便，可重复进行，对慢性难治性哮喘或激素依赖型患者，可作为一种治疗手段。

关键词： 组织胚胎学   胆碱能神经元   宫缩乏力   视皮质   雌激素   糖复合物   细胞化学   组织化学   神经内分泌学   酶活性  

关键词： 胚胎移植   组织实施   质量控制   山羊  

摘要： 从我国国情出发,系统论述了生产条件下山羊胚胎移植的组织实施步骤及质量控制因素。提出了生产条件下山羊胚胎移植的主要质量控制指标:选择适宜的供、受体,并加强饲养管理;用FSH300～350IU以减量法进行供体超排;用孕激素阴道海绵栓配合促性腺激素进行受体同期发情;鲜胚移植采用从供体子宫角手术回收的桑椹胚～囊胚期胚胎,胚胎冷冻或胚胎分割采用囊胚期胚胎,并移植于受体羊子宫角;完整的记录体系。

关键词： 脊髓损伤   修复   脊髓移植   胚胎脊髓   超微结构  

摘要： 目的：观察胚胎脊髓在缓解损伤脊髓的病理反应及其发生发展中的作用。方法：将妊娠１４ｄ大鼠胚胎脊髓植入半切洞损伤的成鼠脊髓后１、３、５、７、１０、１５、３０、４５和６０ｄ时，取材做光镜和电镜观察。结果：单纯脊髓损伤后，发生了出血水肿、变性坏死以及囊腔形成胶质细胞增生和神经纤维再生。胚胎脊髓植入后，明显减轻了神经元和神经纤维的坏死变性程度，并能对损伤神经元实施挽救；有效抑制了病理囊腔的形成，也可填补原发损伤造成的大块组织缺损；防止了胶质细胞过度增生形成瘢痕屏障；明显增加了再生神经纤维的数目。结论：胚胎脊髓对损伤脊髓具有减轻病理反应和促进修复的作用。

关键词： MHC compatibility   embryo transfer   cattle  

摘要： An intact maternal immune system is not essential for successful reproduction but there is good evidence indicating that it plays an important role during pregnancy. The most prominent candidates for maternal immune recognition are the Major Histocompatibility Complex (MHC) antigens. We have investigated the role of embryo-recipient MHC-compatibility in vivo by studying pregnancies after transfer of embryos into 100% compatible or 100% incompatible heifers. Our results showed that MHC antigens are selectively recognized by the immune system of the recipient and suggest that they can influence the outcome of pregnancy. If these results can be confirmed in larger scale studies, new strategies to improve ET pregnancy rates could be applied. (C) 1996 by Elsevier Science Inc.