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摘要： The effect of transplantation of embryonic neural tissue (ENT) on the dynamics of brain edema following heavy craniocerebral trauma (CCT) made to the left parietotemporal area was studied in rats. The brain tissue impedance was measured in the damaged and contralateral hemispheres 1 to 30 days alter the trauma in the animals of three groups: (i) without any procedures after the CCT, (ii) with surgical treatment of the damaged brain area, and (iii) with transplantation of 1-2 mm(3) sensorimotor cortex fragments from Ii-day-old rats grafted into the cavity created by this treatment. At the first day after CCT, the impedance in the damaged hemisphere decreased by 30-37%, while the impedance in the contralateral hemisphere decreased approximately by 20%, compared with the control, which was evidence of the development of intensive generalized edema. In the group of animals with the ENT transplantation, the edema involuted noticeably faster than that in the other two groups: the mean impedance value reached 97.9% of the control value (before the damage) already by the 7th post-traumatic day. Complete recovery of the impedance by the 30th day was observed only in the animals with transplantation. The adequacy of an impedancemetric technique for investigation of the dynamics of water-electrolyte re-distribution in the brain tissue, and the mechanisms underlying corrective effect of ENT transplantation on the edema dynamics in the post-traumatic period are discussed.

关键词： Animals   Enzyme-Linked Immunosorbent Assay   Fluorescent Antibody Technique   Direct   Immunohistochemistry   Insulin   Larva   Pancreas   Perciformes  

摘要： Insulin was sought during the early postembryonic development of gilt-head sea bream, Sparus aurata, using ultrastructural, immunohistochemical and biochemical techniques. The endocrine pancreas appeared at hatching (Day 0) as a single cluster of morphologically similar cells. Secretory granules formed from Day I onwards but the cells could only be identified as insulin-producing B cells at the end of the endotrophic period (Day 3-Day 4). Insulin-immunoreactive cells were detected in the pancreatic primordium from hatching onwards and their number increased after the end of the endo-exotrophic period. Early insulin production was also found using an ELISA method on homogenates of prelarvae and larvae. Insulin levels were fairly high during the endotrophic period, decreased strongly at mouth opening, and then increased at the end of the endo-exocrine period. The origin and role of the large amount of hormone detected during the strictly endotrophic phase of ontogenesis are discussed in light of data on other vertebrates. (C) 1998 Academic Press.

关键词： MHC class Ia genes   transgenic mice   placenta   maternal tolerance   embryonic lethality  

摘要： Among the numerous hypotheses proposed to explain the absence of fetal rejection by the mother in mammals, it has been suggested that regulation of expression of the polymorphic major histocompatibility complex (MHC) at the fetal-maternal interface plays a major role. In addition to a lack of MHC gene expression in the placenta throughout gestation, the absence of polymorphic MHC molecules on the early embryo, as well as their low level of expression after midgestation, could contribute to this important biologic phenomenon. In order to test this hypothesis, we have produced transgenic mice able to express polymorphic MHC class I molecules early in embryogenesis. We have placed the MHC class la gene H-2K(b) under the control of a housekeeping gene promoter, the hydroxy-methyl-glutaryl coenzyme A reductase (HMG) gene minimal promoter. This construct has been tested for functionality after transfection into mouse fibroblast L cells. The analysis of three founder transgenic mice and their progeny suggested that fetoplacental units that could express the H-2K(b) heavy chains are unable to survive in utero beyond midgestation. We have shown further that a much higher resorption rate, on days 11 to 13 of embryonic development, is observed among transgenic embryos developing from eggs microinjected at the one-cell stage with the pHMG-K-b construct than in control embryos. This lethality is not due to immune phenomena, since it is observed in histocompatible combinations between mother and fetus. These results are discussed in the context of what is currently known about the regulation of MHC expression at the fetal-maternal interface and in various transgenic mouse models. (C) 1998 Wiley-Liss, Inc.

关键词： 抗原   CD44   肾小球肾炎   免疫组织化学   胚胎   肾  

摘要： 目的观察ＣＤ４４在胚胎肾组织和肾小球疾病患儿肾活检组织中的表达，以探明ＣＤ４４在肾组织损伤发病机理中的作用。方法应用碱性磷酸酶标记抗体技术，观察ＣＤ４４在胚胎肾组织和肾小球疾病患儿肾活检组织中的表达。结果（１）在胎儿和正常人肾组织中，肾小球内ＣＤ４４表达阴性，间质弱阳性；（２）肾小球疾病患儿肾活检组织中，ＣＤ４４表达异常，其表达部位主要位于系膜细胞严重增殖的区域、硬化病灶形成处和明显纤维化的间质，且表达强度与病变的程度呈正相关。

关键词： 彩色多普勒显像   清宫术   宫内残留物  

摘要： 由于药物流产、人工流产、引产、顺产、剖腹产等造成胚胎组织残留在宫腔内，使患者出血量增多，经期延长，宫腔感染，甚至大出血。在彩色多普勒显像（ＣＤＦＩ）引导下可有效地清除残留胚胎组织，减少出血及痛苦。１一般资料本文报告我院经ＣＤＦＩ引导下在４７例患者清宫...

关键词： 细胞外基质   层粘连蛋白   肾小球   胚胎   肾组织  

摘要： 目的观察肾小球细胞外基质成分在胚胎和成熟肾组织中表达的时空顺序、细胞来源，为阐明它们在肾组织中的生物学功能提供理论依据。方法选用针对板层蛋白的α１、α２、β１、β２、γ１链、Ⅳ型胶原α１、α３、α５链和纤维连接蛋白的单抗隆抗体，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作为对照。结果板层蛋白的α１、β２、γ１链在肾组织中的表达随着胎龄增加和肾脏成熟而增加，但各自分布不同；α２链在肾组织未见表达；β１链在幼稚肾小球为阳性，成熟肾小球中则为阴性。纤维连接蛋白和Ⅳ型胶原α３、α５链在肾单位有血管侵入时才出现表达，Ⅳ型胶原α１链则在肾发育早期即有表达。它们各自分布并不一致。结论在肾小球发生和成熟过程中存在着细胞外基质成分分布的时空顺序及个别链抗原的隐蔽或丢失，推测它们可能对肾小球的发生。

关键词： 胎儿   组织发生   组织化学   皮肤  

摘要： 目的研究国人胚胎皮肤的组织发生和组织化学变化。方法取５６例胎龄１３～３８周胎儿皮肤，石蜡切片，用Ｈ－Ｅ和组织化学方法染色，光镜观察。结果１３周表皮由３层细胞组成，周皮完全脱落，１７周出现角化，眼睑部２０周出现角化。２１周后表皮可分为４层细胞。黑素颗粒于１５周出现于毛囊原基处。随胚胎发育黑素颗粒逐渐增多；１６周出现汗腺原基，１８～２１周分化为腺泡；１３周出现毛囊原基，１５周形成毛囊和毛干，１６周形成皮脂腺，２５周形成立毛肌；组织化学：上皮细胞和毛囊上皮细胞内有糖原颗粒和糖蛋白类物质。毛乳头及皮下组织含有透明质酸和硫酸软骨素。毛囊内根鞘细胞含ＡＣＰ。结论随胎龄增加，皮肤发育渐完善。

关键词： 医学   能力培养   教育   专科   组织胚胎学  

关键词： 细胞死亡   组织化学   细胞凋亡(Apoptosis)   DNA结合蛋白   原位杂交   免疫细胞化学   程序性   组织胚胎学   名词   Southwestern印迹  

关键词： 濒危植物   四合木   体细胞胚胎   蒺藜科  

摘要： 通过对四合木愈伤组织诱导和体细胞胚胎形成过程中组织学观察的研究，得出以下结果：１）茎尖、茎段、肉质叶和花蕾四种外植体中花蕾的愈伤组织诱导率最高，其中花蕾的肉质花托是四合木体细胞胚胎发生的良好外植体来源；２）基本培养基为改良Ｍｓ固体培养基：ａ．附加０．１ｍｇ／Ｌ６－ＢＡ和０．５ｍｇ／Ｌ，２．４－Ｄ可诱导产生大量的淡黄色疏松状愈伤组织；ｂ．愈伤组织在去除外源植物生长调节物质的条件下，经一年左右继代培养以后可诱导产生体细胞胚胎；３）胚性愈伤组织经早期２～４细胞的体细胞胚至具胚柄或不具胚柄的球形胚、心形胚以及成熟胚各个时期形成完整小植株；４）胚性愈伤组织经液体悬液培养３０ｄ后可直接在显微镜下观察到球形。