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关键词： 三疣梭子蟹   胚胎发育   组织学  

摘要： 对三疣梭子蟹 (Portunustrituberculatus)胚胎发育早期 (卵裂至原肠胚期 )进行了组织学观察 ,结果发现 :卵排至体外约 5 2h后开始卵裂 ,卵裂方式为表面卵裂 ,卵裂至 2 5 6细胞时 ,胚胎发育进入囊胚期。囊胚为实囊胚 ,囊胚后期 ,16个排成倒喇叭形的预定内胚层细胞与聚集在其附近的其他细胞一起内陷形成原肠。预定内胚层细胞脱离原肠后 ,进行 1次切向分裂 ,形成卵黄细胞和内胚层细胞。与此同时 ,胚区细胞不断分裂 ,产生视叶原基和胸腹原基 ,不久 ,2个胸腹原基逐渐愈合形成胸腹突。随胚胎发育 ,在似桥细胞带上出现大颚原基、大触角原基 ,随后在大触角原基与视叶原基之间的腹中线上发生口凹。在小触角原基产生后 ,胚胎发育进入卵内无节幼体期。

关键词： 组织学   胚胎学   教学   计算机多媒体技术   医学教育  

摘要： 近年来，随着高等教育改革不断深入，高等医学院校加强了计算机教学手段，以提高课堂教学效率。为此，我们利用计算机多媒体技术，进行了组织学理论课教学的初步尝试，并就相关问题作了问卷调查，现小结如下。

关键词： 解脲脲原体   流产   超薄切片   胚胎组织  

摘要： 初步探讨解脲脲原体 (Uu)感染与自然流产的相关性。对 82例自然流产、44例人工流产 (对照组 )的胚胎组织进行 Uu的人工分离培养 ,并对部分组织的超薄切片及培养物负染片置电镜下观察。结果显示 ,自然流产胚胎组织 U u的检出率为 6 4.6 % (5 3/ 82 ) ,与对照组相比 6 .8% (3/ 44 ) ,具有显著性差异 (P<0 .0 0 1) ;电镜下观察 ,U u检出阳性标本中合体滋养细胞膜和细胞滋养细胞膜表面见大量的 U u颗粒 ,与阳性培养物经负染后所见颗粒相似 ,而 U u阴性对照标本中未见此颗粒 ,提示 :Uu可引起宫内感染 ,损伤绒毛膜滋养细胞 ,是导致自然流产的重要病原体之一。

关键词： cathepsin L   proteases   embryos   development   Artemia  

摘要： Embryos and larvae of the brine shrimp, Artemia franciscana, contain a novel cathepsin L-like cysteine protease (ACP) composed of 28.5- and 31.5-kDa subunits. Both subunits of the ACP are glycosylated, and seven isoforms of the protease were identified by isoelectric focusing with pI values ranging from 4.6 to 6.2. Several clones containing sequences coding for the 28.5-kDa subunit of the ACP were isolated from an Artemia embryo cDNA library in lambda ZAP II. One clone of 1229 bp, with an open reading frame of 1014 bp, was sequenced and found to contain 50-65% amino acid sequence identity with several members of the cathepsin L subfamily of cysteine proteases. The mature protein predicted from this sequence consisted of 217 amino acids with a mass of 23.5 kDa prior to post-translational modifications. The mature protein showed 68.6% amino acid sequence identity with human cathepsin L and 73.9% identity with cathepsin L-like proteases from Sarcophaga. peregrina and Drosophila melanogaster. The full-length cDNA clone analyzed in this study (pCP-3b) was renamed AFCATL1 (A. franciscana Cathepsin L1) and the sequence has been deposited in the Genbank database, accession number AF147207. Northern blot analyses identified a single transcript of about 1.4 kb in both embryos and young larvae of Artemia. Southern blot analyses of Artemia genomic DNA treated with various restriction endonucleases indicated a single gene for the ACP. The catalytic subunit of the ACP was tightly associated with a 31.5-kDa protein, which may localize the protease to nonlysosomal sites in embryos and larvae.

关键词： Oreochromis niloticus   tilapia   development   embryo   larva   histology   hatching glands   pancreatic islet  

摘要： The developmental stages of Oreochronis niloticus are similar to those described in other mouth-breeding tilapias except that, as in zebrafish, no cavity was found in the blastula. Variation in the rate of development of the embryo and larva of O. niloticus was found within a clutch of eggs as well as between clutches. Hatching glands are described for the first time in tilapias. They are widely distributed within the ectoderm covering the head, body, tail, and surface of the yolk sac near its attachment to the embryo. Timing of larval development is similar to that in other mouthbrooding tilapias, but is slower than that found in substrate-spawning tilapias. A pneumatic duct connects the swimbladder to the digestive tract and swimbladder inflation and initiation of feeding occurs at about the same time. The digestive tract of the larva 8 and 9 days after fertilization is similar to that found in the adult, except that there are no digestive glands. An endocrine pancreatic islet was first seen 76 h after fertilization. A prominent thymus gland is present at 100 h. Hematopoietic tissue develops in the vicinity of the pronephros during early larval development. A spleen develops later, 7 days after fertilization. (C) 2001 Wiley-Liss. Inc.

关键词： 脊髓损伤   胚胎脊髓   脊髓移植   大网膜   椎旁肌  

摘要： 目的　探讨带蒂的大网膜、椎旁肌并胚胎脊髓移植对损伤脊髓的修复作用。方法　采用大鼠脊髓半切洞损伤模型 ,将动物分为胚胎脊髓移植 +大网膜组、胚胎脊髓移植 +椎旁肌组、胚胎脊髓移植组、损伤对照组。移植后 1、2、4、8、12周 ,进行HE、Nissl、嗜银染色、电镜检查和免疫细胞化学检查 ,观察移植物存活、分化及其与宿主之间的关系。结果　提供血运的胚胎脊髓移植到损伤的脊髓后 ,移植物逐渐增大 ,充满损伤的洞腔 ,并可在宿主脊髓内继续分化发育 ,与宿主脊髓形成部分纤维和血管联系。结论　带蒂的大网膜和胚胎脊髓组织联合移植能较好地修复损伤的脊髓。

关键词： 褪黑素   受体   胚胎外周组织   MEL   MR  

摘要： 目的 :探讨人胚胎外周组织褪黑素 (Mel)受体 (MR)体内分布的蛋白结合活性及信号转导途径。 方法 :应用放射配体结合法检测人胚胎外周组织 MR,并以 GTPγS观察其对 Mel特异结合的影响。 结果 :经饱和分析、动力学分析及特异性分析证明人胚胎心、肝、肾及甲状腺等 16种组织均存在 Mel特异结合位点 ,亚细胞分布研究表明这些组织中以细胞核及线粒体MR含量最高 ;GTPγS能够抑制 Mel与其受体的结合 ,使 MR的结合容量或亲和力降低。结论 :MR在人胚胎组织存在广泛 ,为解释 Mel作用的广泛性提供了实验依据。实验结果支持 MR是由抑制性

关键词： 基础医学   学科:基本知识   人体解剖学   人体组织学   人体胚胎学  

ISBN: (纸本)7530829483

摘要： 本书包括人体解剖学、组织学和胚胎学三个部分，以问答的形式介绍了这些学科领域的基本理论和基础知识，对于那些倍受关注的新知识，新进展则做到了重点介绍。

关键词： liver   development   stem cells   culture   explant   gene therapy  

摘要： Ex vivo embryonic liver explant culture is a novel and attractive approach to obtain abundant hepatic and hematopoietic stem cells. Gene therapy of autologous hepatic and hematopoietic stem cells represents an alternative therapeutic approach to liver transplantation for genetic and metabolic disorders. In this study we characterize the growth and differentiation of hepatic stem cells utilizing embryonic liver cultures. Day 9.5 liver buds are microdissected and cultured under specific conditions. Modulation of growth conditions by addition of hepatocyte growth factor, Flt-3 ligand, and stem cell factor leads to enrichment of hepatic progenitor cells in embryonic liver explants. Under these conditions, we also demonstrate the role of a novel marker PRAJA-1 to identify hepatic stem cells and transitional hepatocytes. Utilization of dexamethasone enhanced pseudolobule formation with increased hepatocytic and biliary differentiation. Transforming growth factor-beta leads to enrichment of biliary cells in the culture, Gut formation is enhanced in the presence of interleukin-3 and blood formation by increasing the mesodermal tissue in these cultures. We also show increased retroviral-mediated expression of the green fluorescent protein expression in the expanded hepatic and hematopoietic stem cells under different culture conditions. Thus, the embryonic liver explant culture is an attractive source for hepatic progenitors and is a possible step towards generating nontumorigenic immortalized hepatocytes with possible transplantation applications.

关键词： 纳络酮   新生儿呼吸暂停   治疗  

摘要： 目的观察钠络酮佐治新生儿呼吸暂停的疗效.方法设治疗组和对照组,两组都在综合治疗的基础上,治疗组加用钠络酮3～4天,对照组用洛贝林、安茶碱等传统中枢兴奋药物,两组比较疗效.结果治疗组总有效率为91.4%;对照组总有效率为50%,两组相比有显著差异(P<0.01).结论钠络酮佐治新生儿呼吸暂停疗效显著,未见明显副作用.