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关键词： 解剖学   组织胚胎学   教材   编写结构  

关键词： 胚胎   肾   整合素  

摘要： 目的观察细胞外基质的整合素受体在胚胎肾发育中表达的时空顺序，揭示其在胚胎肾发育中的作用。方法选用针对整合素α１、α２、α３、α５、α６、αｖ的单克隆抗体，采用间接免疫碱性磷酸酶技术，观察其在１１例胎儿肾中的表达和分布，并以正常成人肾组织为对照。结果除α２、α６在未成熟肾小球出现一过性表达外，其余各链随着肾小球成熟表达逐渐增加，但各自分布不同。α１、αｖ在肾小球和间质广泛分布，α３仅出现于小球，α５在幼稚小球分布于系膜区，而成熟小球其分布以肾小球基底膜为主。成熟肾组织中α２、α６在肾间质和小管壁大量表达。结论整合素α链在胚胎肾发育过程中存在着一定的时空顺序。

关键词： B超   诊断   宫腔内   胚胎组织残留  

摘要： 1.资料与方法 本组38例早孕妇女,年龄21～35岁,平均26岁,临床表现均为药物流产后不同程度的阴道流血7～30天不等。经B超检查,术后证实为胚胎组织残留(蜕膜、绒毛组织)及部分凝血块。38例患者有正常产,人流及药流史者35例,首次流产者1例,有剖腹产史者2例。 采用SAL—32B型超声显像仪,探头频率为5MHz,膀胱适度充盈,取仰卧位,经腹壁耻骨联合上纵、横扫查为主。2.结果 38例药物流产后,宫内胚胎组织残留患者声像图表现子宫长大和形态饱满者31例,占81.6％。

关键词： 扬子鳄   十二指肠   组织发生   胚胎  

摘要： 本文观察了１８例不同时间扬子鳄（Ａｌｉｇａｔｏｒｓｉｎｅｎｓｉｓ）胚胎十二指肠的组织发生过程．孵化第１０天十二指肠出现形态分化．１６天，上皮细胞增殖为３～４层，．肠腔扩大．３０天，上皮局部出现突起，多具２层细胞．３４天，间充质已分化为固有膜、粘膜下层、环行肌层及纵行肌层，环行肌层较厚，平均约为２８μｍ．４０天，上皮为单层柱状，纹状缘明显，开始出现原始小肠腺．５２天，杯状细胞较多．６２天，各层结构与成体时相似；扫描电镜下观察，绒毛为指状、舌状和嵴状．

关键词： 胚胎   脾   组织学   人类   组织发生  

摘要： 用３５例人类胚胎脾标本研究了脾的组织发生过程。结果显示，６周时，脾原基已经出现，８周前由未分化的间充质构成。１１周时已出现脾索与脾窦。１７周出现白髓，直到２６周才形成典型的动脉周围淋巴鞘和脾小体，各例的脾小体内均未发现生发中心。１１周已出现稀疏的造血灶，１５～２２周造血细胞最为密集，２６周后逐渐减少，３４周时仍未消失。１９～２４周，白髓内淋巴细胞多呈弥散状分布，其中有大量细胞凋亡，提示在白髓发育过程中存在某种对淋巴细胞进行选择的机制。自１１周起，脾窦内即有大量巨噬细胞存在，表明在发育早期，脾已具备滤血功能。

摘要： The earliest evidence of the development of the cardiac vessels in mammals is the emergence of subepicardial blood islands, which are thought to originate from mesenchymal progenitors. In order to identify these progenitor cells, we have studied the immunohistochemical localization in the heart of Syrian hamster embryos of the type 2 vascular endothelial growth factor receptor, the earliest molecule known to be expressed in the vasculogenic cell lineage. Only a few immunoreactive subepicardial mesenchymal cells were present by 10 days post coitum. By 11 days post coitum, the subepicardial mesenchymal cells became abundant at the dorsal part of the ventricle, the atrioventricular and the conoventricular grooves. About 20% of cells were labelled with the antibody. Immunoreactive cells were isolated or formed pairs, short cords, rounded clusters or ring-like structures at the subepicardium or, occasionally, within the ventricular myocardium. Other labelled cells were simultaneously cytokeratin immunoreactive. By 12 days post coitum, most immunoreactive mesenchymal cells have been replaced by a capillary network. We propose that an active process of vascular differentiation occurs between 10 and 12 days post coitum in the subepicardium of this species, and it might be a suitable model for the study of vasculogenetic mechanisms. (C) 1998 Chapman & Hall.

关键词： embryo development   histology   somatic embryogenesis   Pisum sativum  

摘要： Somatic embryos have been induced from pea (Pisum sativum L.) shoot apices and cotyledons of immature embryos. The former explants allowed a better embryo development than the latter. Histological studies showed that in both cases, somatic embryos have a multicellular origin. The cells surrounding the shoot apex-derived embryos contained starch grains but not the embryos themselves. The callus cells derived from immature embryo cotyledons did not accumulate starch. Hence, we suspect that numerous pea somatic embryos failed to develop because of the lack of nutrient reserves in the callus which are required to sustain full embryo development. (C) Elsevier, Paris.

关键词： Animals   Ear, Middle/cytology   Ear, Middle/embryology   Humans   Infant, Newborn   Mesoderm/cytology   Opossums/physiology   Temporal Bone/cytology  

摘要： Objective: The fate of embryonic middle ear mesenchyme from a postgestational infant ear has been speculative. Recently a volume analysis of human neonatal temporal bones demonstrated that embryonic mesenchyme disappeared by redistribution and thinning to surface a growing middle ear space.(1) If this model is accurate, interaction with amniotic fluid and the gestational environment should not influence mesenchymal behavior. Therefore an opossum marsupial model was compared with human data. Methods: The temporal bones of opossum pups (20 to 36 days of age) were sectioned for histologic analysis. Computations were made for the volume of the middle ear air cavity (VAC), volume of the bone cavity (VBC), volume of mesenchyme (VM), and percentage of the middle ear occupied by mesenchyme (%M), which were plotted against height using regression statistics. These data were compared with human neonatal (0 to 30 days of age) temporal bones. Results: In both the opossum and the human the VAC and the VBC increased in parallel with growth of the body. In the opossum the VAC and VBC both grew at 0.148 mm(3)/mm of body length. In humans, both the VAC and VBC grew 6.1 mm(3)/cm of body length. The VM in the opossum remained constant at 0.98 mm(3), regardless of body length. In humans the VM remained constant at 71.7 mm(3), regardless of body length. Therefore the %M proportionately decreased inversely with increasing ear size in both the opossum and the human neonate. Conclusion: This study supports a simple and credible explanation for the illusion of mesenchymal disappearance in the neonatal middle ear. The mesenchymal connective tissue redistributes to cover a larger surface area in a persistently enlarging cavity, These findings occur in different species, whether gestation is completed in an intrauterine or an extrauterine environment.

关键词： tranquilizers   cytoskeleton   deciliation   Golgi   mitochondria   cell motility   sea urchin, Lytechinus pictus (Echinodermata)  

摘要： The mitotic inhibitor, chloral hydrate, induces ciliary loss in the early embryo phase of Lytechinus pictus. It causes a breakdown of cilia at the junction of the cilium and the basal body known as the basal plate. This leaves the plasma membrane temporarily unsealed. The basal apparatus accessory structures, consisting of the basal body, basal foot, basal foot cap, striated side arm, and striated rootlet, are either misaligned or disintegrated by treatment with chloral hydrate. Furthermore, microtubules which are associated with the basal apparatus are disassembled. Mitochondria accumulate at the base of cilia - underneath the plasma membrane - and show alterations in their structural organization, The accumulation of mitochondria is observed in 40% of all electron micrograph sections while 60% show the areas mostly devoid of mitochondria. The microvilli surrounding a cilium and striated rootlet remain intact in the presence of chloral hydrate. These results suggest that deciliation in early sea urchin embryos by chloral hydrate is caused by combined effects on the ciliary membrane and on microtubules in the cilia. Furthermore, it is suggested that chloral hydrate can serve as a tool to explore the cytoskeletal mechanisms that are involved in cilia motility in the developing sea urchin embryo.

关键词： 早产儿   婴儿体重   发育成熟   身体各器官   出生体重   健康状况   存活率   育婴法   幼鼠   组织胚胎学  

摘要： 早产儿是指胎龄为28～37周娩出,出生体重在1000～2500克,身体各器官尚未发育成熟的新生儿。 早产儿身体尚未发育成熟,就匆匆降生了。因此,显得有几分“苍白”和“无奈”。一旦护理不周,极易夭折。在医院里,医生通常将早产儿放入加温的特制保育箱中,进行特殊的护理。即使如此,婴儿的体重仍增长迟缓,健康状况及存活率还是不尽如人意,仍有一些乳婴带着遗憾离去。