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关键词： murine embryogenesis   ets genes   PEA3 group   transcription factor  

摘要： ERM, ER81 and PEA3 are three highly related transcription factors belonging to the ETS family. Together they form the PEA3 group within this family. Little data is yet available regarding the roles of these three genes during embryonic development. A prerequisite to investigations in this field is to obtain an accurate spatio-temporal expression map for the erm, er81 and pea3 genes. To this end, we have used in situ hybridization to compare their expression patterns during critical stages of murine embryogenesis. We report that all three genes are expressed in numerous developing organs coming from different embryonic tissues. The three genes appeared co-expressed in different organs but presented specific sites of expression, so that the resultant expression pattern could in fact reveal several distinct functions depending upon isolated and/or various combinations of the PEA3 member expression. These results suggest that erm, er81 and pea3 genes are differentially regulated, probably to serve important functions as cell proliferation control, tissue interaction mediator or cell differentiation, all over successive steps of the mouse organogenesis.

关键词： 端粒酶   肿瘤标志物   胚胎发育  

摘要： 对不同时期的胚胎组织和肿瘤组织中端粒酶活性进行了分析,结果显示:胚胎组织中端粒酶活性水平随发育阶段和组织而异,呈现出明显的阶段性特征。恶性肿瘤组织细胞普遍存在端粒酶活性,同时恶性化倾向比较大的中重度不典型增生肠腺瘤组织也出现端粒酶活性升高的趋势。由此提示,(1)端粒酶也属于胚胎性的肿瘤标志物;(2)结直肠癌前病变组织也可出现端粒酶活性。

关键词： FMR1基因   选择剪接   脆性X综合征  

摘要： 本实验分析了6月龄胚胎心、肝、肾、脾4种组织中FMR1基因的选择剪接表达。在所分析的胚胎组织中，FMR1mRNA主要异构体与该胚胎大脑皮层的主要异构体相同，与成人大脑皮层的主要异构体完全不同。这一差异提示FMR1基因的选择剪接表达存在发育转换。FMR1基因的选择剪接表达在胚胎和成人组织中的主要差别表现在外显子12和外显子17编码多肽的去留上，对这两段多肽功能的研究将具有重要意义。

关键词： 大鲵   胚胎发育   组织学  

摘要： 通过人工繁殖，获得了两批大鲵的受精卵及其幼苗．利用组织学方法研究了大鲵的早期胚胎发育，并描述了其主要特征．同时，就此和其他两栖动物的胚胎发育进行了比较讨论，并指出了其共性与特殊性．

关键词： maturation   reserve accumulation   embryogenesis late phases   ABA (abscisic acid)   recalcitrant seeds  

摘要： In order to improve the late phases of Theobroma cacao L. embryogenesis from tissues of maternal origin, zygotic embryogenesis and somatic embryogenesis were compared, with respect to morphological, histological, and physiological parameters. Zygotic embryogenesis could be divided into three steps: (a) embryogenesis sensu stricto, (b) a growth period in which cotyledonary embryos reached their final dimensions, and (c) a maturation period in which embryos accumulated protein and starch reserves, dehydrated to a water content equal to 30%, and underwent a modification in soluble sugar composition. Monosaccharides and sucrose contents decreased to the benefit of the oligosaccharides raffinose and stachyose. The formation of somatic embryos by use of basic protocols was studied to define the limiting factors that could lie behind their poor development. Morphological abnormalities of somatic embryos, which represented 80% of the total population, were described. A histological study showed that somatic embryos lacked starch and protein reserves;moreover, their water content was much higher than that of their zygotic counterparts. Introducing a growth period into the culture protocol made for better embryo development. Adding sucrose and abscisic acid to the maturation medium was effective in increasing reserve synthesis and resulted in higher germination, conversion, and acclimatization rates.

ISBN: (纸本)7562703779

关键词： gene targeting   embryonic stem cells   vasculogenesis   in vitro development  

摘要： Vascular endothelial-cadherin (VE-cadherin) is exclusively expressed in endothelial cells and is strictly located at cell-to-cell junctions. As the other members of the cadherin family, VE-cadherin is able to mediate a homotypic type of cellular interaction in a Ca2+-dependent manner. In the mouse embryo, VE-cadherin transcripts are detected at the earliest stages of vascular development. To ascertain if VE-cadherin expression is required for the assembly of endothelial cells into vascular structures, we generated VE-cadherin negative mouse embryonic stem cells (VE-cadherin(-/-) ES cells) by gene targeting and examined the consequences on vascular development of ES-derived embryoid bodies (EBs), In contrast to wild-type EBs, we observed that endothelial cells remained dispersed and failed to organize a vessel-like pattern in VE-cadherin(-/-) ES-derived EBs, However, dispersed VE-cadherin(-/-) ES-derived endothelial cells expressed a large range of other endothelial markers, Moreover, the targeted null-mutation in the VE-cadherin locus did not interfere with the hematopoietic differentiation potential of ES cells, These irt vitro experiments are consistent with a pivotal role of VE-cadherin in vascular structure assembly.

关键词： 实验性胃溃疡   颌下腺   织化学   大鼠   组织胚胎学   免疫组织   化学研究   第四军医大学   胃溃疡愈合   时间点  

摘要： 大鼠实验性胃溃疡自愈过程中颌下腺５－ＨＴ及其受体的免疫组织化学研究王炜①黄威权②（①解放军第４０１医院病理科②第四军医大学组织胚胎学教研室）本文采用北京医科大学组织胚胎学教研室的方法将ＳＤ大鼠制成实验性胃溃疡模型，通过免疫组织化学ＡＢＣ法染色，结合原...