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大车前(Plantago major L. "Giant Turkish.")不仅有很高的药用价值,在生态学研究方面也是重要模式植物。大车前的组织培养工作,目前报道很少。对其组织培养体系的建立,为筛选大车前耐盐突变体和基因转化建立高效的体外再生系统和实验平台体系。通过愈伤组织诱导和直接不定芽再生途径, 建立了大车前(Plantago major L. "Giant Turkish.")的快速高效再生系统。叶片外植体在含有1.0 mg/L NAA的MS培养基中培养3周后,形成愈伤组织,愈伤组织在含4.0 mg/L 6-BA的MS培养基中成功再生,得到完整植株。种子外植体在含0.2 mg/L IAA和1.0 mg/L TDZ的MS培养基中培养4周后产生大量的丛生芽,对9株再生植株进行RAPD检测表明,部分植株在DNA水平上发生了变异。 植物抵御盐胁迫的一个重要机制是在液泡中积累Na+,从而使细胞质内Na+保持在较低水平,并且降低细胞渗透势。Na+运输到液泡是由液泡Na+/H+逆向转运蛋白完成的。本实验室已从盐生植物盐角草(Salicornia europaea)和番杏(Tetragonia tetragonioides)中分别克隆得到SeNHX1和TtNHX1基因。本文研究了SeNHX1和TtNHX1基因在酵母突变体里的作用。TtNHX1和SeNHX1蛋白在缺陷型酵母菌株里的表达能够提高这些菌株对NaCl、LiCl和潮霉素的抗性,提高到与野生型相当的抗性水平。说明TtNHX1和SeNHX1有着与酵母ScNHX1相似的细胞定位和作用机制,是ScNHX1的功能类似蛋白。

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本文主要通过样线法和样方法相结合,进行了大量的群落学调查和分析,分别从植物区系、物种多样性的垂直分布格局和森林群落类型三个方面分析了神农架植被的基本特征及其物种多样性,结果表明: 1.神农架地区具有很高的物种丰富度,有高等植物3,479种,隶属于1,010属,202科。 其中,蕨类植物305种,80属,32科;种子植物3,174种,930属,170科,其中裸子植物32种,19属,6科,被子植物3,142种,911属,164科;单子叶植物501种,175属,21科,双子叶植物2,641种,736属,143科。植物区系属的分布区类型中北温带分布型最多,其次为东亚分布、泛热带分布、东亚北美间断分布、旧世界温带分布以及热带亚洲分布。中国特有成分占5.65%,较全国的8.12%低。温热比(温带分布型(8-11)属数与热带分布型(2-7)属数的比值)为1.200,比全国(0.385)高。 调查样方中共出现高等植物784种,隶属于454属,144科,其中蕨类植物41种,32属,16科;种子植物743种,422属,128科,其中裸子植物20种,14属,5科,被子植物723种,408属,123科;单子叶植物86种,58属,11科,双子叶植物637种,350属,112科。属的分布区类型中北温带分布型最多,其次为东亚分布、泛热带分布、东亚北美间断分布、旧世界温带分布以及热带亚洲分布。温热比为1.52,草本层>乔木层>灌木层分别为2.18、1.76和1.14。 2.神农架植被类型多样,具有常绿阔叶林、常绿落叶阔叶混交林、落叶阔叶林、针阔混交林、亚高山针叶林、硬叶常绿阔叶林和亚高山灌丛草甸等自然植被类型。本文,依据乔木物种的重要值将神农架地区的森林植被划分出了69个类型。用Twinspan将调查的森林群落划分为32组,能基本上反映群落间相似的关系。 3.神农架地区具有完整的植被垂直带谱:海拔900 (1300) m以下为常绿阔叶林带;海拔900 (1300) m~1500 (1800)ⅡI为常绿落叶阔叶混交林带;海拔1500 (1800) m-2000 (2200)m为落叶阔叶林带;海拔2000 (2200) m~2400 (2600)m为针阔混交林带:海拔2400 (2600)m以上为亚高山针叶林带。神农架地区植被的垂直带的分化从总体上比较显著,但由于小生境的异质性和人为干扰,垂直带谱又具有一定的模糊性和次生性。南北坡具有一定的差异,但不十分明显,也说明神农架植被的过渡性。 4.神农架物种多样性的垂直分布格局。神农架的物种多样性与海拔的关系,类似于“中间膨胀”规律(mid-altitude bulge),在中低海拔处生物多样性最高。通过二次多项式回归拟合,得到如下拟合曲线: 1)海拔与总体物种数:y= _14.445x2+ 34.74lx+42.07,Xd=1.203km; 2)海拔与乔木层物种数:y=-6.9707x2+ 21.334x+0.2004,Xdrl.530km; 3)海拔与灌木层物种数:y=-6.1599x2+ 9.9747x+30.991,Xd=0.8 lOkm: 4)海拔与草本层物种数:y= _3.9907x2+ 10.455x+15.35,Xd-1.308km; 5)海拔与乔木层Shannon-Wiener指数:y=_0.3337x2+ 0.9877x+0.2537,Xd' 1.480km; 6)海拔与灌木层Shannon-Wiener指数:y=-0.1938xz+ 0.422lx+1.2103,Xd=1.089km: 7)海拔与草本层Shannon-Wiener指数:y=_0.1072x2+ 0.294lx+0.9954,Xd=1.372km; x为海拔( km),y为各物种多样性指标,Xd为物种多样性的最大时的海拔。 从这些拟合曲线中可以看出:总体物种多样性在海拔1200m左右的常绿落叶阔叶混交林带最高:乔木层物种多样性在海拔1500m左右的常绿落叶阔叶混交林带与落叶阔叶林的过渡带最高;灌木层物种多样性在海拔800-llOOm左右的常绿阔叶林与常绿落叶阔叶混交林带的过渡带最高;草本层物种多样性在海拔1300-1400m左右的常绿落叶阔叶混交林带最高。 但物种多样性随海拔变化有许多的起伏和波动。这些波动有些反映了群落的垂直带谱随海拔梯度变化的特点,在垂直带谱的过渡区物种多样性往往较高;有些波动反映了一些特殊的生境,有些反映了人为活动的影响,造成了神农架植被的次生性。因此,影响神农架物种多样性垂直分布的因素有:植被本身的性质和特点、过渡带的特点、生境的异质性和人为活动。 5.神农架植被水平地带性的过渡性。海拔1300m以下的植物属的分布区类型的温热比南坡总是比北坡小,而且相差十分显著,反映了神农架作为植被分界线的价值。神农架南坡的基带植被是常绿阔叶林,因此南坡属于中亚热带。北坡的基带植被,虽然也有常绿树种的零星分布,甚至有小块的常绿阔叶林,完全由于小生境所至,分布的主要类型是常绿落叶阔叶混交林,应属于北亚热带。因此,神农架是中、北亚热带重要的过渡地带。神农架地区中北亚热带的具体分界线宜按照分长江干流和汉水的水岭来划界,即猴子石、大窝坑、神农架、神农顶、老君山一线,南坡属于中亚热带,北坡属于北亚热带。 总之,神农架处于我国中、北亚热带的过渡带,具有过渡带的性质,具有很高的物种多样性,拥有完整的植被垂直带谱,具有多种多样的植物群落及其组成的生态系统。而且,具有我国许多特有植物和珍稀濒危保护植物和许多资源植物。因此,神农架植被在我国植被体系中具有重要的地位,是我国生物多样性最丰富的地区之一,是生物多样性保护的关键地区,也应是生物多样性研究的热点地区。 另外,调查分析了黄山和万朝山植被及其物种多样性与垂直分布格局,结果表明: 6.黄山样方中共出现高等植物259种,隶属于263属,110科,其中蕨类植物14种,II属,8科,种子植物345种,152属,105科,其中裸子植物9种,8属,6科,被子植物336种,144属,99科,其中单子叶植物37种,27属,6科,双子叶植物299种,117属,90科。属的分布区类型中北温带分布最多,其次为东亚分布和泛热带分布,再次为东亚北美间断分布、热带亚洲分布以及旧世界温带分布,与神农架和万朝山也较相似,但热带分布的属更多一些。温热比为1.1875,灌木层>草本层>乔木层,分别为1.3818、1.2609和1.2143。 黄山的森林植被类型有针叶林、常绿阔叶林、常绿落叶阔叶混交林、针阔混交林、落叶阔叶林和竹林。Twinspan将调查的森林群落划分为22组,反映群落间相似的关系,比较清楚和适用。依据乔木物种的重要值将森林植被划分出了34个类型。黄山物种多样性的与海拔的关系不十分明显。黄山植被的垂直带谱不是十分明显,将其垂直带谱划分为:海拔1300m(1500m)以下为常绿阔叶林带;海拔1300m(1500m)-1500m(1600m)常绿落叶阔叶混交林 带;1500m(1600m)以上为落叶阔叶林、黄山松林、山地灌木草丛带。垂直带谱在不同坡向上有差别,东、南、西坡的相似性较大,而北坡与其差别较大。 7.万朝山样方中共出现高等植物490种,隶属于339属,124科,其中蕨类植物21种,18属,11科,种子植物469种,321属,113科,其中裸子植物9种,7属,4科,被子植物460种,314属,109科,其中单子叶植物47种,37属,11科,双子叶植物413种,277属,98科。植物属的分布区类型中,北温带分布所占最多,其次为泛热带分布、东亚分布、东亚北美间断分布、旧世界温带分布以及热带亚洲分布,。温热比为1.3366,草本层>乔木层>灌木层,分别为1.5429、1.4063和1.0645。 万朝山的植被类型包括针叶林、落叶阔叶林、针阔混交林和常绿落时阔叶混交林,但没有典型的常绿阔叶林。依据乔木物种的重要值将森林植被划分出了20个类型。万朝山物种多样性与海拔的关系则不十分明显。万朝山的人为干扰比较强,植被的次生性很大,南、北坡物种多样性随海拔升高的起伏较大。

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The muntjacs (Muntiacus, Cervidae) are famous for their rapid and radical karyotypic diversification via repeated tandem chromosome fusions, constituting a paradigm for the studies of karyotypic evolution. Of the five muntjac species with defined karyotyp

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Somatic cell nuclei of giant pandas can dedifferentiate in enucleated rabbit ooplasm, and the reconstructed eggs can develop to blastocysts. In order to observe whether these interspecies cloned embryos can implant in the uterus of an animal other than th

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鱼类主要分布于青藏高原周边, 是一群适合于急流生活的 科鱼类。在独龙江流域7 个点共采 集271 号  鱼类标本(隶属 属、 属和异齿 属) , 结合各采集点数据绘制大鳍异齿 、藏 和扁头 的分布 直方图, 结果显示, 藏 ( E. labiatum) 在流速较快的独龙江下游各采集点的种群数量较上游高, 更适应急流生 境。同时研究了这3 种  鱼类的体长与体重的关系, 参数b (W = aLb) 的范围在218201 和310131 之间, 均为异 速生长; 藏 的生长类型最接近等速生长。

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为了探讨铜绿微囊藻对浮游甲壳动物溞类的毒害效应,试验选取了两种不同株系(产毒和非产毒)的藻种,采取利用其培养液的方法,以研究铜绿微囊藻在生长过程中向水体中释放的毒素或类毒素物质对溞类的效应以及比较不同株系间效应的差异性。研究结果表明:(1)试验所选铜绿微囊藻产毒和非产毒株系的培养液均能对大型溞(Daphnia magna)的生长繁殖构成影响,表现为低剂量起促进效应,高剂量起抑制效应;(2)铜绿微囊藻产毒株较非产毒株更能影响大型溞的存活;(3)铜绿微囊藻产毒和非产毒株对大型溞的生长影响差异不大,但对其繁殖却

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为了研究"水华"微囊藻多糖及其对水体化学和生态特性的影响,以去离子水、pH5的缓冲液和pH9.2的缓冲液为提取液,分别在4℃和80℃条件下从滇池"水华"微囊藻中提取多糖,并对其所提多糖部分化学特征进行分析.结果表明pH9.2的缓冲液所提多糖总得率最高,为2.25%;pH5的磷酸盐缓冲液所提多糖总得率最低,为0.383%.溶解性分析表明,不同提取液所提多糖在所试验的几种溶剂中表现为不溶、分散或部分溶解,未能找到将多塘完全溶解的溶剂.气相色谱和气-质联用分析表明,不同提取液所提多糖都含有中性单糖鼠李糖、阿拉伯

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CO2浓度提高时,微拟球藻吸收醋酸钠的速率增加2倍。混养生长的藻细胞最大光合作用速率、光合作用效率、无机碳半饱和常数和无机碳饱和的光合作用速率均显著低于光自养条件下生长的。

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用抑制性差减杂交结合SMARTcDNA合成和RACE PCR技术克隆到雌核发育银鲫 (Carassiusauratusgibelio)肌酸激酶M 3 CK基因的全长cDNA。银鲫M 3 CKcDNA全长 15 5 1bp ,编码 380个氨基酸 ,与普通鲤鱼(Cyprinuscarpio)M3 CK的氨基酸序列同源性高达 95 %。种系分析表明 ,银鲫M3 CK与其它脊椎动物的肌肉型肌酸激酶聚为较近的一支 ,与鲤鱼的M 3 CK聚在一起 ,与脑特异型肌酸激酶及线粒体型肌酸激酶分歧较大。虚拟Northern

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Two Saprolegnia isolates, JY isolated from silver crucian carp (Carassius auratus gibelio Bloch) and BMY isolated from zebra fish (Brachydanio rerio Hamilton) came from infections occurring concurrently in different locations in China. To confirm whether the two isolates were from the same Saprolegnia clone, comparative studies have been carried out based on their morphological, physiological and molecular characteristics. Observations showed that morphologically (both asexual and sexual organs) the two isolates were broadly similar and both isolates under-went repeated zoospore emergence. Comparing 704 base pairs of internal transcribed spacer (ITS) region and the 5.8S rDNA, we found isolates JY and BMY shared an identical ITS sequence with a minor variation (99.6 % similarity). Forty available sequences for representatives Saprolegnia spp. belonged to four phylogenetically separate clades. The two studied isolates fell within clade I that comprised a group of isolates which showed almost an identical ITS sequence but had been identified as a number of different morphological species. our findings suggest that isolates JY and BMY appear to belong to the S. ferax clade and this clade (1) contains a number of closely related phylogenetic species. This is distinct from the more common fish pathogenic isolates, which belong to the S. parasitica clade (III) and are characterized by having cysts decorated by bundles of long hooked hairs and two further clades (II and IV) containing largely saprotrophic or soil born species. (C) 2009 Published by Elsevier Ltd on behalf of The British Mycological Society.

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Defensins are a group of cationic antimicrobial peptides which play an important role in the innate immune system by exerting their antimicrobial activity against pathogens. In this study, we cloned a novel beta-defensin cDNA from medaka (Oryzias latipes) by rapid amplification of cDNA ends (RACE) technique. The full-length cDNA consists of 480 bp, and the open reading frame (CRF) of 189 bp encodes a polypeptide of 63 amino acids (aa) with a predicted molecular weight of 7.44 kDa. Its genomic organization was analyzed, and Southern blot detection confirmed that only one copy of beta-defensin exists in the medaka HNI strain. RT-PCR, Western blot and immunohistochemistry detections showed that the beta-defensin transcript and protein could be detected in eyes, liver, kidney, blood, spleen and gill, and obviously prevalent expression was found in eyes. Antimicrobial activity of the medaka beta-defensin was evaluated, and the antibacterial activity-specific to Gram-negative bacteria was revealed. Furthermore, the lipopolysaccharide (LPS), a major component of the outer membrane of Gram-negative bacteria, was demonstrated to be able to induce about 13-fol up-regulation of the beta-defensin within first 12 h. In addition, promoter and promoter mutagenesis analysis were performed in the medaka beta-defensin. A proximal 100 base pair(bp) sequence (+26 to -73)and the next 1700 bp sequence (-73 to -1755) were demonstrated to be responsible for the basal promoter activity and for the transcription regulation. Three nuclear factor kappa B (NF-kappa B) cis-elements and a Sp1 cis-element were revealed by mutagenesis analysis to exist in the 5' flanking sequence, and they were confirmed to be responsible for the up-regulation of medaka beta-defensin stimulated by LPS. And, the Sp1 cis-element was further revealed to be related to the basal promoter activity, and transcriptional factor II D (TFIID) was found to be in charge of the gene transcription initiation. All the obtained data suggested that the novel medaka beta-defensin should have antimicrobial activity-specific to Gram-negative bacteria, and the antibacterial immune function should be modulated by NF-kappa B and Sp1. (C) 2008 Elsevier Ltd. All rights reserved.

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In order to imitate the restoration succession process of natural water ecosystem, a laboratory microcosm system of constant-flow-restoration was designed and established. A eutrophycation lake, Lake Donghu, was selected as the subject investigated. Six sampling stations were set on the lake, among which the water of station IV was natural clean water, and others were polluted with different degrees. Polyurethane foam unit microbial communities, which had colonized in the stations for a month, were collected from these stations and placed in their respective microcosms, using clean water of station IV to gradually replace the water of these microcosms. In this process, the healthy community in clean water continuously replaced the damaged communities in polluted water, the restoration succession of the damaged communities was characterized by weekly determination of several functional and structural community parameters, including species number (S), diversity index (DI), community pollution value (CPV), heterotrophy index (HI), and similarity coefficient. Cluster analysis based on similarity coefficient was used to compare the succession discrepancies of these microbial communities from different stations. The ecological succession of microbial communities during restoration was investigated by the variable patterns of these parameters, and based on which, the restoration standards of these polluted stations were suggested in an ecological sense. That was, while being restored, the water of station 0 (supereutrophycation) should be substituted with natural clean water by 95%; station I (eutrophycation), more than 90%; station II (eutrophycation), more than 85%; station III (eutrophycation), about 85%; station V (mesoetitrophycation), less than 50%. The effects of the structural and functional parameters in monitoring and assessing ecological restoration are analyzed and compared. (C) 2007 Elsevier Ltd. All rights reserved.