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关键词： 出版时间   主书   新版图书   组织学与胚胎学   书号   主编   编辑人员   模块化实验   出定  

摘要： 《微生物学模块化实验教程》主编:何伟徐旭士书号:978-7-04-034240-6出版时间:2014年4月定价:17.00字数:18万《微实主书出定字《发育生物学实验》主编:董巍张俊争书号:978-7-04-034392-2出版时间:2014年4月定价:17.00字数:18万

关键词： Androgenic embryos   Datura metel   Meristem excision   Secondary embryogenesis   Wounding   Zygotic embryos  

摘要： The induction of secondary embryos in androgenic and zygotic embryos of Datura mete! (L) (Solanaceae) was investigated by excising their shoot and root meristems and culturing the hypocotyls on Nitsch medium. Androgenic embryos produced secondary embryos on the hypocotyl. Histological sections showed secondary embryo development was independent of maternal tissue with no connection to the maternal vascular system. The zygotic embryos produced shoot buds and adventitious roots from the cut surface. Shoot buds had vascular connections with the maternal tissue. Excision of both meristems produced more secondary embryos than excision of the apical meristem alone. Excision of apical meristems in embryogenically competent immature embryos and their in vitro culture could potentially produce secondary embryos on the hypocotyls. The significance of these results is the clonal multiplication of the primary embryo at an early stage of embryo development. The meristem excision steps are easily performed under sterile conditions. (C) 2013 Elsevier B.V. All rights reserved.

关键词： Transcriptional derepression   Embryonic axis formation   Mesoderm induction   Down syndrome   Polycomb group proteins   Xenopus  

摘要： Mesoderm and embryonic axis formation in vertebrates is mediated by maternal and zygotic factors that activate the expression of target genes. Transcriptional derepression plays an important role in the regulation of expression in different contexts;however, its involvement and possible mechanism in mesoderm and embryonic axis formation are largely unknown. Here we demonstrate that XDSCR6, a Xenopus homologue of human Down syndrome critical region protein 6 (DSCR6, or RIPPLY3), regulates mesoderm and embryonic axis formation through derepression of polycomb group (PcG) proteins. Xdscr6 maternal mRNA is enriched in the endoderm of the early gastrula and potently triggers the formation of dorsal mesoderm and neural tissues in ectoderm explants;it also dorsalises ventral mesoderm during gastrulation and induces a secondary embryonic axis. A WRPW motif, which is present in all DSCR6 homologues, is necessary and sufficient for the dorsal mesoderm- and axis-inducing activity. Knockdown of Xdscr6 inhibits dorsal mesoderm gene expression and results in head deficiency. We further show that XDSCR6 physically interacts with PcG proteins through the WRPW motif, preventing the formation of PcG bodies and antagonising their repressor activity in embryonic axis formation. By chromatin immunoprecipitation, we demonstrate that XDSCR6 releases PcG proteins from chromatin and allows dorsal mesoderm gene transcription. Our studies suggest that XDSCR6 might function to sequester PcG proteins and identify a novel derepression mechanism implicated in embryonic induction and axis formation.

关键词： embryonic development   tissue modelling   glassy dynamics   supercooled fluid   tissue viscoelasticity   active matter  

摘要： Many biological tissues are viscoelastic, behaving as elastic solids on short timescales and fluids on long timescales. This collective mechanical behaviour enables and helps to guide pattern formation and tissue layering. Here, we investigate the mechanical properties of three-dimensional tissue explants from zebrafish embryos by analysing individual cell tracks and macroscopic mechanical response. We find that the cell dynamics inside the tissue exhibit features of supercooled fluids, including subdiffusive trajectories and signatures of caging behaviour. We develop a minimal, three-parameter mechanical model for these dynamics, which we calibrate using only information about cell tracks. This model generates predictions about the macroscopic bulk response of the tissue (with no fit parameters) that are verified experimentally, providing a strong validation of the model. The best-fit model parameters indicate that although the tissue is fluid-like, it is close to a glass transition, suggesting that small changes to single-cell parameters could generate a significant change in the viscoelastic properties of the tissue. These results provide a robust framework for quantifying and modelling mechanically driven pattern formation in tissues.

关键词： WPBL   组织学与胚胎学   实验教学  

摘要： 目的:探讨WPBL在组织学与胚胎学实验教学中的应用效果。方法:采用WPBL教学法,对2009级临床医学专业学生的组织学与胚胎学实验教学进行改革。结果:WPBL组的实验标本考试成绩平均分高于对照组,经统计学处理,有显著性差异(t=1.71,P<0.05)。问卷调查显示,WPBL教学法有助于提高学生学习兴趣,问题的分析能力以及协作能力等。结论:WPBL教学法有利于提高临床医学专业学生的组织学与胚胎学的实验考试成绩,且锻炼和提高了学生的多种能力。WPBL教学模式值得在以后的教学中继续推广应用。

关键词： 体细胞胚   大豆   受体系统   转基因方法  

摘要： 大豆体细胞胚胎遗传转化体系是提高外源基因遗传稳定性,克服嵌合体的有效途径,因此建立高效稳定的大豆体细胞胚胎组织培养体系并广泛应用于大豆的遗传转化是完善大豆遗传转化研究的重要研究内容。本研究对目前大豆体细胞胚胎再生体系的组织学和遗传转化的研究进展进行了总结,分析了大豆体细胞胚胎组织培养和遗传转化的影响因素。应在现有的组织学研究的基础上,充分考虑影响大豆体细胞胚胎诱导的因素,对遗传转化方法进行改良,以期为大豆体细胞胚胎遗传转化体系提供新的研究思路。

关键词： 多媒体技术   组织学与胚胎学   学生成绩  

摘要： 组织学与胚胎学是一门以微观形态学为主的重要医学基础课程。由于学生刚开始接触医学专业术语，使用传统教学方法，难免枯燥乏味，使学生感觉该课程难学难记，易产生厌学情绪。为了激发学生的学习兴趣，提高教学质量，我们增加了多媒体教学手段，以期取得较好的教学效果。

关键词： 组织学与胚胎学教学   传统教学模式   医学检验专业   实验教学内容   改革   专业培养目标   专业课程   教学效果  

摘要： 目前大多数医学院校对于医学检验专业组织学与胚胎学教学仍然采用“先理论，后实验”的传统教学模式[1]，纯理论内容偏重，没有充分利用现代化的教学手段，也没有科学地运用临床案例进行教学，因此不能与医学检验的专业课程有机融合和相互渗透，也不能充分调动学生的学习积极性和主动性，使得组织学与胚胎学教学效果受到影响。理论与实验一体化教学模式是把一门课程的理论教学内容与实验教学内容融为一体的现场教学模式。在组织学与胚胎学教学中，应用理论与实验一体化教学模式，是符合形态学特点的，同时也可以充分体现医学检验专业培养目标的特色。教师边讲授边示范，学生边听讲边观察，以达到理论与实践结合，提高教学效果的目的。