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关键词： cardiovascular   embryonic   American alligator   Alligator mississippiensis   development   hypoxia  

摘要： Chronic hypoxic incubation is a common tool used to address the plasticity of morphological and physiological characteristics during vertebrate development. In this study chronic hypoxic incubation of embryonic American alligators resulted in both morphological (mass) and physiological changes. During normoxic incubation embryonic mass, liver mass and heart mass increased throughout the period of study, while yolk mass fell. Chronic hypoxia (10% O-2) resulted in a reduced embryonic mass at 80% and 90% of incubation. This reduction in embryonic mass was accompanied by a relative enlargement of the heart at 80% and 90% of incubation, while relative embryonic liver mass was similar to the normoxic group. Normoxic incubated alligators maintained a constant heart rate during the period of study, while mean arterial pressure rose continuously. Both levels of hypoxic incubation (15% and 10% O-2) resulted in a lower mean arterial pressure at 90% of incubation, while heart rate was lower in the 10% O-2 group only. Acute (5 min) exposure to 10% O-2 in the normoxic group resulted in a biphasic response, with a normotensive bradycardia occurring during the period of exposure and a hypertensive tachycardic response occurring during recovery. The embryos incubated under hypoxia also showed a blunted response to acute hypoxic stress. In conclusion, the main responses elicited by chronic hypoxic incubation, namely, cardiac enlargement, blunted hypoxic response and systemic vasodilation, may provide chronically hypoxic embryos with a new physiological repertoire for responding to hypoxia.

关键词： ATP   embryogenesis   hypoxia   Japanese medaka   metabolism   NMR   Oryzias latipes   phosphocreatine  

摘要： In vivo P-31 nuclear magnetic resonance spectroscopy (NMR) was used to determine phosphometabolite changes in medaka (Oryzias latipes) during embryogenesis and hypoxia. NMR data were acquired using a flow-through NMR tube perfusion system designed to both deliver oxygenated water to embryos and accommodate a hypoxic challenge. Measurements of embryogenesis at 12- and 24-h intervals throughout 8 days of development (n=3 per time point, 900 embryos per replicate) and during acute hypoxia (n=6, 900 embryos at Iwamatsu stage 37 per replicate) were performed via NMR, and replicate samples (n=4, 250 embryos each) were flash frozen for HPLC analysis. The hypoxic challenge experiment consisted of data acquisition with recirculating water (pre-hypoxic control period;1 h), without recirculating water (hypoxic challenge;1 h), then again with recirculating water (recovery period;1.3 h). Concentrations of ATP, phosphocreatine (PCr), orthophosphate (P-i), phosphomonoesters (PME), phosphodiesters (PDE), and intracellular pH (pH(i)) were determined by NMR, and ATP, ADP, AMP, GTP, GDP, and PCr were also determined via HPLC. During embryogenesis, [ATP] and [PCr] as determined by HPLC increased from 1-day post fertilization (DPF) levels of 0.93 +/- 0.08 and 2.48 +/- 0.21 mu mol/mg (dry tissue), respectively, to 7.24 +/- 0.77 and 15.66 +/- 1.08 mu mol/mg, respectively, by day 8. [ATP] and [PCr] measured by both NMR and HPLC fluctuated over 1-3 DPF, then increased significantly (p < 0.05) over 3-8 DPF, while [PME] and [PDE] decreased (p < 0.05) throughout embryogenesis. NMR and HPLC measurements revealed 1-3, 4-5, and 6-8 DPF as periods of embryogenesis significantly different from each other (p < 0.05), and representing important transitions in metabolism and growth. During hypoxic challenge, [ATP] and [PCr] declined (p < 0.05), [PME] and [PDE] decreased slightly, and [Pi] increased (p < 0.05). All phosphometabolites returned to pre-hypoxia concentrations during recovery. The pH(i) dec

关键词： zebrafish   enveloping layer   cytokeratin   cyt1   neural   autoneuralization   explants   BMP  

摘要： We have analyzed the roles of cell contact during determination of the outermost enveloping layer (EVL) and deeper neurectoderm in zebrafish embryos. Outer cells, but not deeper cells, are specified to express the EVL-specific marker, cyt1 by late blastula. EVL specification requires cell contact or close cell proximity, because cyt1 is not expressed after explant dissociation. The EVL may be homologous to the Xenopus epithelial layer, including the ventral larval epidermis. While Xenopus epidermal cytokeratin gene expression is activated by bone morphogenetic protein (BMP) signaling, zebrafish cyt1 is not responsive to BMPs. Zebrafish early gastrula ectodermal explants are specified to express the neural markers opl (zic1) and otx2, and this expression is prevented by BMP4. Dissociation of zebrafish explants prevents otx2 and opl expression, suggesting that neural specification in zebrafish requires cell contact or close cell proximity. This finding is in contrast to the case in Xenopus, where ectodermal dissociation leads to activation of neural gene expression, or autoneuralization. Our data suggest that distinct mechanisms direct development of homologous lineages in different vertebrates. (C) 2004 Wiley-Liss, Inc.

关键词： 组织激肽释放酶   脑中风   组织胚胎学   脑缺血  

摘要： 我们以组织激肽释放酶或组织激肽释放酶片段免疫异种动物产生组织激肽释放酶特异性的免疫球蛋白，辅以相关技术，制成诊断试剂盒，用于脑缺血免疫学诊断，同时建立中国人正常组织激肽释放酶的标准。我们利用ELISA的方法检测了209例中国人的组织激肽释放酶(HUK)含量，并检查了血糖、血纤维蛋白原、血流变学、低密度脂蛋白等有关的临床指标。同时通过统计学分析，分析了激肽释放酶(HUK)与一些临床指标的关系。综上所述，我们得出中国人的组织激肽释放酶(HUK)的值的分布情况为偏态分布，95﹪的可信值＜1.99ng/ml。通过统计学分析，其与年龄、性别无差异。与纤维蛋白原、血糖、血流变学无相关性。与血脂中的低密度脂蛋白呈正相关。我们相信通过人组织激肽释放酶特异性免疫球蛋白及此蛋白相关缺血性脑中风诊断试剂盒的开发，对缺血性脑中风诊断及风险预测方面将会取得更大进步。

关键词： 胚胎干细胞   海藻糖   诱导分化   内皮细胞   组织工程   血管种子细胞  

摘要： 目的：组织工程化血管是治疗血管性疾病最理想的血管替代物，但内皮细胞来源匮乏是制约其临床应用的关键问题。人胚胎干细胞具有全能性和无限增殖的能力，有望成为组织工程化血管种子细胞的新来源，然而其冷冻保存仍是目前亟待解决的问题之一。为此，我们首先对人胚胎干细胞的冻存方法进行了改进，尔后又将其诱导分化为内皮细胞，以期为组织工程化血管提供新的种子细胞来源。 结论： 1hES细胞可用含90％SR+10％DMSO的冻存液冷冻保存，复苏后细胞仍维持胚胎干细胞的各项特性，且核型正常。2冷冻过程中加入0.2M海藻糖可有效提高hES细胞的冷冻复苏率。3维甲酸和TGF-β1可成功诱导hES细胞分化为血管内皮细胞

关键词： 一氧化氮合酶   肾脏发育   免疫印迹   肾小管   组织胚胎学  

摘要： 目的：观察妊娠不同时期胚胎小鼠肾脏nNOS的表达，探讨nNOS在胚胎小鼠肾脏早期发育中的意义。 方法：选用成年健康昆明小白鼠，按雌雄比例3：1同窝饲养，采用检查阴道栓脱落的方法确定雌鼠受孕时间。选取胚龄12天(ED12)、14天(ED14)、16天(ED16)、18天(ED18)的胎鼠及出生时(PDO)仔鼠，分5组，每组各6只母鼠，每只母鼠取2只胎鼠或仔鼠，剖腹取肾脏，常规制作石蜡切片，用SP法对各组切片进行免疫组织化学(IHC)染色及图象分析;用免疫印迹技术(Westernblot)及光密度分析系统分别对各组胎鼠或仔鼠肾脏内nNOS进行定量检测。 结果：(1)ED14组肾脏nNOS在生肾区输尿管芽部位呈阳性表达，其他部位均无阳性表达;ED16组生肾区输尿管芽nNOS表达减弱，肾近端小管呈阳性表达，同时远端小管亦有弱阳性表达;ED18组nNOS阳性表达主要出现在肾近端小管、远端小管及致密斑，髓放线和髓质中的近直小管nNOS表达阳性，而集合管上皮未见nNOS表达，除成熟肾小体肾小囊局部偶见阳性细胞外，各级肾小体nNOS表达均呈阴性;PDO组肾脏nNOS表达部位基本与ED18组相同，致密斑中nNOS呈强阳性表达，髓放线和髓质中远直小管表达亦呈阳性。(2)Westernblot及光密度分析显示：ED14组肾脏nNOS含量最少，随后逐渐增多，PDO组肾脏nNOS含量最多。 结论：(1)胚胎小鼠肾脏nNOS在胚胎第14天开始呈阳性表达，以后含量逐渐升高，出生时含量最高。(2)nNOS表达的部位从生肾区输尿管芽逐渐扩展至肾近端小管、远端小管及致密斑，这一结果表明nNOS在胚胎小鼠肾脏发育的早期阶段起重要作用。

关键词： 学术动态   断层影像解剖学   中国解剖学会   山东大学医学院   医学影像学   组织胚胎学   组织学   刘树伟   陈星荣   功能成像   最新进展   介入放射学   断层解剖   中国医学计算机成像杂志   HRCT  

关键词： renal development   losartan   TGF-beta   electron microscopy  

摘要： The aim of our study was to investigate the histopathological, immunohistochemical and ultrastructural effects of Losartan (a selective angiotensin II type-1 receptor blocker) on renal development in rats. Twelve pregnant rats were divided into control and experimental groups. In the experimental group, Losartan (10mg/kg/day) was given via nasogastric tube, between the sixth day of implantation and time of sacrifice on embryonic days 18 and 20. All formalin-fixed, paraffin wax-embedded renal tissue sections were stained with hematoxylin and eosin or labelled for binding of primary antibodies against transforming growth factor-it (TGF-beta 1,-2,-3) using an avidin-biotin-peroxidase method. For electron microscopic examination, samples were fixed with glutaraldehyde and osmium tetroxide and embedded in araldite. Glomerular basement membrane (GBM) thickness was measured and compared using an unpaired t-test. Angiotensin II type-1 receptor antagonism by Losartan inhibited renal growth and delayed nephron maturation. Increased immunoreactivity of TGF-beta's was observed in developing nephron precursors and interstitial cells in the experimental group. Electron microscopical examination showed that thickening of the GBM was normal in the control group but an irregular thickening was seen in the experimental group (p < 0.001). It was also seen that epithelial cells of developing tubules underwent apoptosis in the experimental group. Thus, renal development in rats seems to depend on an intact renin-angiotensin system. (c) 2005 Elsevier GmbH. All rights reserved.

关键词： 解题   人体胚胎学   医学院校   人体组织学  

ISBN: (纸本)7801946340

摘要： 本书共分两部分，第一部分为习题，第二部分为题解。各部分按统编教材的次序编写，各分为24章，内容包括上皮组织、结缔组织、血液及血发生、软骨和骨、肌组织等。

关键词： 脑缺血再灌流   脑损伤   神经生物学研究室   神经元损伤   组织胚胎学   组织学   缺血性   破格晋升   大鼠   局灶性  

摘要： 1965年生,1988年毕业于泸州医学院医学系,1999年毕业于华西医科大学,获组织胚胎学与解剖学博士学位,并回到泸州医学院解剖学教研室、神经生物学研究室从事教学、科研工作。2002年破格晋升为教授,2004年获四川省学术与技术带头人后备人选。2004年至今在哥本哈根大学蛋白质实验室做访问学者,从事神经突触蛋白neuroplastin结构与功能的研究。