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达乌尔黄鼠染色体银染核仁组织者分析 总被引:2,自引:1,他引:1
达乌尔黄鼠染色体银染核仁组织者分析ANALYSISONCHROMOSOMESAg-NORSOFCITELLUSDAURICUSKeywordsCilellusdauricus;Chromosome;Ag-NOR达乌尔黄鼠(cilellusdauric... 相似文献
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6-Dimethylaminopurine(6-DMAP) Spontaneously Induces Interphase Transition Of Metaphase Mouse Oocytes
6-Dimethylaminopurine(6-DMAP)SpontaneouslyInducesInterphaseTransitionOfMetaphaseMouseOocytes¥SUNQing-yuan(孙青原);GAOShao-rong(高... 相似文献
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贵州疣螈的核型和C-带研究 总被引:5,自引:0,他引:5
贵州疣螈的核型和C-带研究ASTUDYONKARYOTYPESANDC-BANDINGSOFTylototritonkweichowensis关键词贵州疣螈,核型,ZW-染色体,C-带KeywordsTylototritonkweichowensis... 相似文献
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TransformationofOrychophragmusviolaceusUsingAgrobacteriumtumefaciensAndRegenerationofTransgenicPlantsa¥ZHOUJi-ming(周冀明);WEIZh... 相似文献
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兴安盟山杏灌木草原的排序王晓江,章中,刘永军,章海波(内蒙古林业科学研究院,呼和浩特010010)OrdinationofPrunussibiricaShrub-SteppesinXinganLeague,InnerMongolia¥WangXiaojiang;ZhangZong;LiuYongjun;ZhangHaibo(InnerMongoliaAcademyofForestrySciences,Huhhot010010).Chi-neseJournalofEcology,1993,12(1):29-32。ThePrunussibiricashrub-steppesinXinganLeagueofInnerMongoliaarestudiedusinganumberofor-dinationmethods,includingpolarordination(PO),principalcomponentanalysis(PCA)ordinationandcorrespondenceanalysis(COA)ordination,22poltsofPrunussibiricashrub-steppesarec 相似文献
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PALAEOZOOLOGICALMuseumofChina(英汉对照)ThePalaeozoologicalMuse-umofChinafoundedbytheInsti-tuteofVertebratePalaeontologyandPalaeoa... 相似文献
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FactorsAffectingElectro-FusionandElectro-ActivationInSerialNuclearTransplantationInGoat(Carpahircus)EmbryoWANGYu-ge(王玉阁);ZOUX... 相似文献
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生态系统原理与可持续农业 总被引:13,自引:2,他引:13
论述了农业生态系统的能量流动物质循环原理、系统相关原理、相生相克原理、忍耐极限原理、结构功能原理、系统开放原理、限制因子原理、非加和原理、生物竞争原理和竞争排斥原理 ;认为中国生态农业是一种较为典型的可持续发展的农业系统类型 ,建议在国家持续农业发展进程中要积极推行生态农业 . 相似文献
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生态系统健康评价方法初探 总被引:143,自引:13,他引:130
生态系统是维持人类环境的最基本单元,生态系统功能主要体现在两个方面:一是生态服务功能(service);二是价值功能(goods)这两种功能是人类生态和发展的基础,生态系统健康是保证生态系统功能正常发挥的前提,结构和功能的完整性,具有抵抗干扰和恢复能力(resilience)、稳定和可持续性是生态系统健康的特征,生态系统健康评价需要基于生态系统的结构、功能过程来确定指标,包括生态系统的完整性,适应性和效率,生态系统健康评价主要有两种方法:一是指示物种评价,二是结构功能指标评价,结构功能指标评价包括单指标评价,复合指标评价和指标体系评价,指标体系评价中又包括自然指标体系评价,社会-经济-自然复合生态系统指标体系评价,本文针对生态系统健康的不同评价方法进行了对比研究,同时,针对不同的生态系统类型应选择其健康评价方法方面进行了简要的阐述。 相似文献
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湖北3种药用淫羊藿植物等位酶多样性与居群遗传结构 总被引:3,自引:0,他引:3
采用超薄平板微型聚丙烯酰胺等电聚焦电泳方法对湖北3种淫羊藿属(Epimedium L.)药用植物:柔毛淫羊藿(E.pubescens Maxim.)、箭叶淫羊藿(Esagittatum(Sieb.&Zucc.)Maxim.)和巫山淫羊藿(Ewushanense T.S.Ying)的11个自然居群进行了等位酶种内遗传多样性和居群遗传结构以及种间遗传关系的研究。6个酶系统在3种淫羊藿植物中检测到13个酶位点共45个等位基因,分析结果表明:1)3种淫羊藿均具有较高的遗传多样性水平(A=2.6-3.2,P=69.2%-84.6%,Ho=0.274-0.377,HE=0.282-0.369),远高于多年生草本植物和依靠动物传粉植物的平均水平;2)所有居群都显著偏离Hardy—Weinberg平衡,大多数多态位点固定指数(F)明显偏离于0且正负值各半,暗示该属植物可能具有复杂的繁育系统;3)种内和种间的遗传分化度均较低,分别为GST=0.0246-0.0409和0.0495-0.1213,表明种内居群间存在较高的基因流和种间较近的遗传关系;4)聚类分析表明柔毛淫羊藿与箭叶淫羊藿的亲缘关系更近,这与形态学特征、花瓣演化趋势及系统发育分析等方面的研究的结果相吻合。讨论分析认为3种淫羊藿植物的遗传变异特性是由淫羊藿属植物异交与克隆繁殖的混合繁育系统、多年生的生活特性、古老的进化历史和种子的蚁播特性等多因素共同决定的。 相似文献
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颈交感神经阻滞对严重烧伤大鼠肾脏的保护作用及其机制研究 总被引:1,自引:0,他引:1
目的:观察颈交感神经阻滞(CSB)对严重烧伤大鼠肾脏的保护作用,并对其可能机制进行初步探讨。方法:制作放烧严重烧伤伤大鼠大鼠模型,在伤后即刻及连续4天内进行双侧颈交感神经阻滞,观察生命体征、肾功能指标、肾脏组织学改变、血流灌注、抗氧化能力、肾组织Bcl-2表达改变。结果:经过颈交感神经阻滞处理后,伤后各时相点动物肾功能均较对照组为好,组织学病变减轻,器官血流量下降幅度减小,总抗氧化能力好于对照组,免疫组化显示CSB组肾组织中Bcl-2的表达较严重烧伤组明显增高。结论:颈交感神经阻滞可改善严重烧伤大鼠肾脏血液灌注,增强抗氧化能力,预防伤后肾脏功能损害。 相似文献
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The genetic diversity and genetic structure of Potamogeton maackianus A. Benn. in seven lakes of the middle reaches of the Yangtze River were studied using random amplified polymorphic DNA (RAPD). The gene flow and genetic relationships between populations were analyzed in combination with the geographic distribution and the river system of the lakes. A total of 112 bands were amplified and 59 bands (52.7%) were polymorphic. Each of the 86 individuals investigated exhibited a unique genotype. The Shannon index was used to measure genetic diversity, and the total genetic diversity was 0.414 and the mean genetic diversity of populations was 0.148. P. maackianus showed a relatively high level of genetic diversity. Analyses of molecular variance (AMOVA) revealed that 63.8% of the total genetic diversity existed among populations and 36.2% within them, which was consistent with the genetic structure computed by the Shannon index: among-population variation and within population variation accounted for 64.4 and 35.7%, respectively. The gene flow among populations was very limited, and genetic isolation among populations occurred even though they were connected through the Yangtze River. Cluster analysis divided the seven populations into two groups, and the genetic relationships among the populations had no obvious association with their geographic distribution, or the historical relations with the river system of the lakes where they occurred. Mantel tests revealed that distance was an important factor affecting the genetic structure in populations. The development history of P. maackianus populations in Honghu Lake had an obvious effect on its genetic structure. 相似文献
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葡萄糖调节蛋白75(grp75)属于热休克蛋白70家族中的一员,细胞中葡萄糖水平下降时(类似于缺血),grp75表达增高。为研究grp75在缺糖及缺糖再灌注条件下对细胞的作用,本文以中国仓鼠肺细胞株CHL为材料,采用脂质体介导的方法,以grp75表达载体pcDNA3/grp75转染CHL细胞,获得过表达grp75的细胞克隆;置于无糖培养基培养20h及无糖培养12h换含糖培养基继续培养8h(缺糖再灌注)或含糖培养20h,运用MTT法、LDH测定和流式细胞术分析等方法评估细胞损伤程度。MTT测定显示,未转染细胞缺糖再灌流的增殖能力比完全培养20h增殖能力明显降低(p<0.05),且低于无糖培养20h(p<0.05),转染细胞缺糖再灌流的增殖能力明显高于对照组(p<0.01);LDH测定结果显示,未转染细胞缺糖再灌流LDH释放百分比显著高于完全培养20h(p<0.01),与无糖培养20h无明显差别(p>0.05),转染细胞缺糖再灌流LDH释放百分比显著低于对照组(p<0.01);流式细胞术分析表明,转染细胞的凋亡率明显低于对照组。以上结果表明grp75过表达的细胞在缺糖损伤细胞的恢复中具有一定强度的抗损害作用。 相似文献
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Biological organisms continuously select and sample information used by their neural structures for perception and action, and for creating coherent cognitive states guiding their autonomous behavior. Information processing, however, is not solely an internal function of the nervous system. Here we show, instead, how sensorimotor interaction and body morphology can induce statistical regularities and information structure in sensory inputs and within the neural control architecture, and how the flow of information between sensors, neural units, and effectors is actively shaped by the interaction with the environment. We analyze sensory and motor data collected from real and simulated robots and reveal the presence of information structure and directed information flow induced by dynamically coupled sensorimotor activity, including effects of motor outputs on sensory inputs. We find that information structure and information flow in sensorimotor networks (a) is spatially and temporally specific; (b) can be affected by learning, and (c) can be affected by changes in body morphology. Our results suggest a fundamental link between physical embeddedness and information, highlighting the effects of embodied interactions on internal (neural) information processing, and illuminating the role of various system components on the generation of behavior. 相似文献
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兔网织红细胞与K_(562)细胞胞质杂交体(K-RRneo)核基质-中间纤维体系的研究 总被引:2,自引:0,他引:2
本文利用脂质体转基因技术与细胞融合相结合的方法所建立的杂交细胞为研究对象,采用选择性多步抽提配合整装电镜及Western 印迹分析等技术,系统观察了兔网织红细胞、人红白血病K_(562)细胞及两者融合形成的胞质杂交体K-RRneo 细胞的核基质-中间纤维体系结构,着重分析比较了它们之间的胞质波形蛋白纤维成分的变化。实验结果表明:K_(562)细胞的中间纤维为放射状分布,核纤层为网层状,兔网织红细胞胞质中间纤维为细网格状,其间存有不规则的致密物。胞质体杂交细胞(K-RRneo)的核纤层结构稀薄,核基质较亲代K_(562)细胞致密,中间纤维构型呈现与网织红细胞相似的网格状。中间纤维蛋白电泳及Western 印迹结果亦显示K-RRneo 细胞与网织红细胞的带型类似,即缺乏聚合型波形蛋白及聚合前体物波形蛋白单体,仅检测到解聚前、后而与细胞其它组分结合的波形蛋白复合物。这一生化和超微结构特征提示,红细胞排核可能与波形蛋白纤维的解聚及Vimentin 基因关闭有关。实验结果为排核前细胞内原已装配好的Vimentin 趋于解聚,引起中间纤维瓦解,造成核偏位、固缩而最终排出细胞外的排核机制提供了证据。 相似文献