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关键词： hypoxia   metabolic rate   development   heart mass   body mass   hematocrit   hemoglobin   trajectories  

摘要： Chicken embryos were chronically exposed to hypoxia (P-o2 similar to 110 mmHg) during development, and assessed for detrimental metabolic and morphological effects. Eggs were incubated in one of four groups: control (i.e. 151 mmHg), or treated with continuous 110 mmHg (15% O-2) during days 1-6 (H1-6), 6-12 (H6-12), or 12-18 (H12-18) with normoxia during the remaining incubation. Metabolism (V-o2), body mass, hemoglobin (Hb) and hematocrit (Hct) were measured in embryos on days 12 and 18 of incubation and in day-old hatchlings. Ability to maintain V-o2 was acutely measured during a step-wise decrease in P-o2 from normoxia to hypoxia (55 mmHg). On day 12, V-o2 of H1-6 eggs were significantly lower than in the control and H6-12 eggs. P-crit in H6-12 eggs was lower than in control and H1-6 eggs. Body mass of H1-6 and H6-12 embryos on day 1 2 was significantly lower than in control embryos, while in H6-12 embryos, Hct and Hb were higher. On day 18, H6-12 embryos had significantly lower V-o2 than control eggs. Body mass of H6-12 and H12-18 embryos was significantly lower than control embryos. Hct and Hb did not differ between treatments. In hatchlings, mass, Hb and Hct had returned to values statistically identical to controls. However., H6-12 embryos had significantly lower V-o2. Long-term hypoxia altered V-o2 when hypoxic incubation occurred during the middle third of incubation, but not during earlier or later incubation. Thus, chronic hypoxic exposure during critical periods in development altered the developmental physiological trajectories and modified the phenotypes of the developing embryos. (C) 2002 Elsevier Science Inc. All rights reserved.

关键词： VA缺乏   小鼠   HoxGene蛋白表达   胚胎组织   动物实验   维生素A  

摘要： 目的　从发育基因角度探讨维生素A(VA)缺乏导致先天畸形的机理。方法　通过建立小鼠VA缺乏模型 ,用免疫组织化学等方法研究VA缺乏对小鼠胚胎组织Hoxgene蛋白表达水平的影响。结果　维生素A缺乏使胎鼠的Hoxgene蛋白表达明显低于正常对照组 (P <0 0 5 )。VA补充组明显高于VA缺乏组 ,但仍比正常对照组低。

关键词： 多媒体技术   医学CAI   组织胚胎学   教学改革  

摘要： 本文通过《组织胚胎学多媒体课件》的设计、实现和应用,探索了医学CAI课件设计的基本原则及主要工作程序.同时总结了多媒体技术应用于医学CAI所具备的多维、集成、交互、真实、拓展和通用等六大特性.

关键词： DNA指纹图   胚胎组织   亲子鉴定  

摘要： 目的　应用DNA指纹技术对强奸致孕案进行亲子鉴定。方法　分别对 6个案例所涉及的嫌疑犯、孕母的血和胎儿组织或药物流产绒毛提取了DNA ,应用Southern转移 ,辣根过氧化物酶标记的JL - 0 2多位点探针杂交 ,化学发光检测DNA指纹图。结果　通过DNA指纹图的判读和分析 ,5个案例认定父子关系 ,1例排除。结论　应用DNA指纹对强奸致孕案可以做出准确的结果。早孕药物流产的绒毛组织与中孕期的胎儿脑、肺、肌肉或胎盘组织提取的DNA ,均能得到清晰的DNA指纹图谱。对于已腐败组织 。

关键词： 组织胚胎学   信息网   网站规划   网站制作  

摘要： 随着Internet的发展与普及,远程教育逐步发展起来.网络教学已经走进我们的教室,由此高等院校的各学科都希望建立一个关于本学科内容的教学、科研网站.这样,不但能够对学生进行远程辅导,而且方便与同行之间的交流与合作.及时了解专业发展动态,紧跟时代发展.本文结合我的个人体会,淡淡如何免费建立功能较为齐全的组织胚胎学教学、科研网站.

关键词： 花生   组织培养   体细胞胚胎发生   组织细胞学   体细胞胚  

摘要： 成熟花生胚轴在 MS+40 mg/L 2 ,4D+0 .5 mg/L KT培养基中可直接诱导产生体细胞胚 ,降低 2 ,4D的浓度 ,将诱导产生的体细胞胚组织块继代 2～ 3次可诱导产生出米黄色颗粒状的胚性愈伤组织 ,继而产生体细胞胚。花生体细胞胚直接诱导起源于表皮或近表皮的细胞 ,其形成经历了跟合子胚相似的过程。花生胚性愈伤组织的细胞具有细胞小、胞质浓、核大、核仁明显 ,排列紧密的特点。经愈伤组织形成的体细胞胚以单细胞内起源方式发生。首先由体细胞胚单个原始细胞分裂形成 2细胞原胚 ,2细胞原胚继续分裂成 3细胞原胚或 4细胞原胚 ,3细胞原胚或 4细胞原胚继续分裂形成多细胞原胚 。

关键词： CAI技术   组织与胚胎学   教学改革   医学教学  

摘要： 本文结合CAI技术在我教研室教学中的应用,对组织学与胚胎学教学中,应用CAI技术的优点、存在问题及解决办法,浅谈了几点体会.

ISBN: (纸本)7801574729

关键词： SRF   ES cells   actin cytoskeleton   focal adhesion   cell migration  

摘要： The activity of serum response factor (SRF), an essential transcription factor in mouse gastrulation, is regulated by changes in actin dynamics. Using Srf(-/-) embryonic stem (ES) cells, we demonstrate that SRF deficiency causes impairments in ES cell spreading, adhesion, and migration. These defects correlate with defective formation of cytoskeletal structures, namely actin stress fibers and focal adhesion (FA) plagues. The FA proteins FA kinase (FAK), beta1-integrin, talin, zyxin, and vinculin were down-regulated and/or mislocalized in ES cells lacking SRF, leading to inefficient activation of the FA signaling kinase FAK. Reduced overall actin expression levels in Srf(-/-) ES cells were accompanied by an offset treadmilling equilibrium, resulting in lowered F-actin levels. Expression of active RhoA-V14 rescued F-actin synthesis but not stress fiber formation. Introduction of constitutively active SRF-VP16 into Srf(-/-) ES cells, on the other hand, strongly induced expression of FA components and F-actin synthesis, leading to a dramatic reorganization of actin filaments into stress fibers and lamellipodia. Thus, using ES cell genetics, we demonstrate for the first time the importance of SRF for the formation of actin-directed cytoskeletal structures that determine cell spreading, adhesion, and migration. Our findings suggest an involvement of SRF in cell migratory processes in multicellular organisms.

关键词： 组织胚胎学   学生地位   教师作用   医学教育  

摘要： 现代教育观强调学生在认知过程中的主体地位及教师的主导作用。这就要求教师有必要重新设计教学形式，重新组织教学内容。以下就如何在组织学教学中体现学生的主体地位谈几点粗浅体会。