87 resultados para 143-868
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连续2年对“京秀”ד亚历山大”(编号97-2)杂交后代10个单株和“京秀”ד香妃”(编号97-3)杂交后代10个单株成熟期和延迟采收期的糖酸组分含量进行测定,以了解葡萄浆果延迟采收内在品质的变化差异。第二年 对可长期挂果的亲本“京秀”、“亚历山大”和杂交后代单株“97-2-23”、“97-2-24”成熟期和延迟采收期糖酸组分动态变化进行测定,以了解葡萄浆果糖酸品质延迟采收期的动态变化规律。同时对以上四个单株的浆果中蔗糖代谢相关酶活性和浆果呼吸强度进行测定,以对不同蔗糖表现型的产生原因进行探讨。研究表明: 葡萄延迟采收,浆果内可溶性糖变化可分为积累型和稳定型两种类型。延迟采收3周,糖积累型的8个单株浆果 可溶性糖显著积累,而稳定型的12个单株的糖与成熟时不存在显著差异。浆果主要积累果糖和葡萄糖,这两种糖的 动态变化趋势基本一致,但果糖变化幅度较大。两种类型的有机酸含量在延迟采收期间变化不大,没有显著差异。 糖积累型的“京秀”和“97-2-23”延迟采收期间各蔗糖分解酶(酸性转化酶、中性转化酶、蔗糖合成酶分解方 向)活性持续升高,但糖稳定型的“亚历山大”和“97-2-24”延迟采收第3周时急剧降低。此外,果实成熟和延迟 采收期间两种糖表现型浆果的呼吸速率也存在差异。浆果的蔗糖分解酶活性和呼吸速率存在的差异可能是两种类型 延迟采收期间糖含量存在差异的重要原因。
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牡丹(Paeonia suffruticosa Andr.)是芍药科芍药属牡丹组植物,花大、色艳、型美、香郁、药用范围广、文化内涵丰富,被尊为“国色天香”、“花中之王”。我国植牡丹、赏牡丹有1600多年的历史,培育了许多价值高的品种,遗憾的是个别黄色、鲜红色、绿色等珍贵品种不断消失,而且现有的一些文化价值与观赏价值极高的古牡丹、著名的牡丹园的老牡丹均出现了衰弱现象,有的已奄奄一息。为了探索传统牡丹品种消失及牡丹衰老的原因,本研究在充分调查、整理国内品种资源的基础上,总结了牡丹品种的传承和消失情况,掌握了古牡丹的资源状况。通过连作土壤栽培试验证明了牡丹连作障碍的存在,并选定了生长在同一区域的5、10、15、20、25、30年生6个株龄的‘洛阳红(Luo Yang Hong)’为研究对象,从形态指标的调查、生理指标的测定、根际土壤及根系浸提液的化感成分分析三个方面着手,确定了牡丹开始衰老的时期;揭示了牡丹衰老机理;总结了古牡丹保留、复壮、养护办法;为牡丹专类园的管理及可持续性发展提供了理论和技术指导。本研究主要结果如下: 1、牡丹品种和古牡丹资源 通过对中国牡丹品种资源的文献查阅和实地考察,系统整理了我国不同时代的品种状况,调查结果表明:宋、元、明、清共有品种1109种,目前仅存143种,品种资源消失十分严重。收集整理了49处古牡丹资料,并据此绘制了我国目前古牡丹分布图;实地调查了17处24株古牡丹,详细介绍了部分品种的来历传说、生长状况和衰亡原因。5个优良传统品种在中国科学院植物研究所牡丹种质资源圃内得以保存,其中潞城古牡丹,植株最大(高2.3 m,冠径5.6 m),且生长旺盛;西溪牡丹属丰花品种,40年植株可开花811朵。 2、牡丹连作障碍 利用牡丹连作根际土壤及其浸出液栽培牡丹,结果表明,播种苗及分株苗的生长均受到了抑制;连作年限越久的处理抑制作用越强;根际土壤浸出液对牡丹生长的影响较大,对前期地下部和后期地上部都有很强的抑制作用,而且还抑制了上胚轴休眠的解除;根际土壤对后期株高和展叶幅的影响较大,对播种苗前期生根影响不大。牡丹存在连作障碍现象,连作障碍是牡丹衰弱的重要原因。 3、牡丹衰老时间及机理 通过对6 个株龄‘洛阳红’的形态、生理指标及根际土壤化感成分的比较得出,牡丹在同一地方大约栽植15 年后开始衰弱,20 年以内应该采取复壮措施。利用气相色谱—质谱联用技术(Gas Chromatograph-Mass Spectrometer, GC-MS)检测到根际土壤及根系浸提液中主要存在:烷烃、烯烃、芳香烃、醇、醚、酚醌、有机酸、醛、酮、酯、苯、胺等12 类有机物。对比分析得出有12 种物质可能是根系分泌物,根际土壤中可能具毒害作用的物质有40 种,栽植牡丹使土壤中增加的物质有24 种。 4、古牡丹复壮技术及应用 栽培基质中添加活性炭、沙子、麦饭石等均能有效的促进牡丹的生长,以活性炭的效果最好。对“汉牡丹”实施了综合复壮措施,效果明显。
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Restriction maps of rDNA repeats of five species of Colobinae and three outgroup taxa, Hylobates leucogenys, Macaca mulatta, and Macaca irus, were constructed using 15 restriction endonucleases and cloned 18S and 28S rRNA gene probes. The site variation between Rhinopithecus roxellana and Rhinopithecus bieti is comparable to that between Presbytis francoisi and Presbytis phayrei, implying that R. bieti is a valid species rather than a subspecies of R. roxellana. Phylogenetic analysis on the 47 informative sites supports the case for Rhinopithecus being an independent genus and closely related to Presbytis. Furthermore, branch lengths of the tree seem to support the hypothesis that the leaf monkeys share some ancestral traits as well as some automorphic characters.
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通过葡聚糖 Sephadex G-50凝胶过滤和反相高压液相层析等手段,对无指盘臭蛙皮肤分泌液进行分离纯化,得到了高纯度的多肽分离峰.分别采用体外培养的大鼠胰岛和INS-1胰岛β细胞系检测分离峰的促胰岛素释放活性.结果表明,所得多肽既可促进原代培养的大鼠胰岛分泌胰岛素,又可以促进INS-1细胞胰岛素释放;运用飞行质谱仪测定该促胰岛素释放肽的相对分子质量,其大小为1 868.此外,利用鸡胚尿囊绒毛膜(CAM)体内模型检测,发现该多肽还具有显著的抑制血管生成活性.
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The action of Pallas' viper (Agkistrodon halys pallas) venom on blood coagulation was examined in vitro and a strong anticoagulant effect was observed. This action was abolished after treatment with a specific inhibitor of phospholipase A(2) activity (p-bromophenacyl bromide), revealing a procoagulant action in low concentrations of treated venom (around 1 mu g/ml). The effect of the venom an haemostasis was further characterized by measuring its ability to activate purified blood coagulation factors. It is concluded that A. halys pallas venom contains prothrombin activation activity. A prothrombin activator (aharin) was purified from the venom by Sephadex G-75 gel filtration and ion-exchange chromatography on a Mono-Q column. It consisted of a single polypeptide chain, with a mol. wt of 63,000. Purified aharin possessed no amidolytic activity on chromogenic substrates. It did not act on other blood coagulation factors, such as factor X and plasminogen, nor did it cleave or clot purified fibrinogen. The prothrombin activation activity of aharin was readily inhibited by ethylenediamine tetracetic acid (a metal chelator), but specific serine protease inhibitors such as diisopropyl fluorophosphate and phenylmethanesulfonyl fluoride had no effect on it. These observations suggest that, like those prothrombin activators from Echis carinatus and Bothrops atrox venoms, the prothrombin activator from A. halys pallas venom is a metalloproteinase. (C) 1998 Elsevier Science Ltd. All rights reserved.
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Albumin, the most abundant protein components of blood plasma, is synthesized and secreted by liver cells in vertebrates. Recently, it was demonstrated that frog Bombina maxima albumin is also expressed in skin. Both B. maxima albumins from skin and serum
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本实验用家兔20只,以夹闭肠系膜上动脉造成肠系膜上动脉夹闭性休克(SMAO)模型。经测定红细胞超氧化物歧化酶(SOD)活性,血浆及肾组织中自由基脂质过氧化的代谢产物丙二醛(MDA)含量的变化。发现SMAO时,血浆及肾组织MDA含量明显增高,而红细胞SOD活性降低。提示:氧自由基及其介导的脂质过氧化对其病变过程起了一定的作用。
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The Hainan gibbon (Nomascus hainanus) is one of the most endangered primates in the world, confined to mature natural forest in Hainan Island, China. We assessed changes in habitat condition on the island between 1991 and 2008, using vegetation maps generated by remote-sensing images. We defined forest suitable for gibbons based on composition, tree size and canopy cover. During the 17-year period, the area of suitable gibbon forest decreased by 540 km(2) (35%) across the whole island, and by 6.3 km(2) (7%) in the locality of the sole remaining gibbon population at Bawangling National Nature Reserve. The forest patches large enough (>1 km(2)) to support a gibbon group decreased from 754 km(2) to 316 km(2) in total area, and from 92 to 64 in number. Suitable natural forest was mainly replaced by plantations below 760 m, or degraded by logging, grazing and planting of pines above 760 m. Meanwhile, forests in former confirmed gibbon areas became more fragmented: mean area of patches decreased by 53%. We mapped the patches of natural forest in good condition which could potentially support gibbons. We recommend a freeze on further expansion of plantations between core patches at Bawangling, Jiaxi-Houmiling and Yinggeling Nature Reserves in accordance with forest protection regulations; establishment of nature reserves in currently unprotected natural forest patches elsewhere in line with the local government's nature reserve expansion policy; and active natural-forest restoration between remaining fragments at Bawangling. (C) 2010 Elsevier Ltd. All rights reserved.
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GATA基因在脊椎动物和非脊椎动物的发育中行使重要的功能,该家族的成员在进化上也足非常保守的.脊椎动物的GATA基因分为两个亚群:GATA1/2/3和GATA4/5/6.通过生物信息分析,在文吕鱼的基因缓中找到了3个GATA基因:一个GATA1/2/3业家族基因,两个GATA4/5/6亚家族基因:还找到一个类GATA基因.还克隆了白氏文昌鱼(Branchiostoma belcheri)GATA123的一段序列,并研究了它在早期胚胎发育中的表达图式.结果表明GATA123在原肠胚的中内胚层表达,而在神经胚晚期和幼体早期,GATA123在脑泡和消化道中部区域表达.这种表达模式与头部发育的重要基因Otx相类似.结果提示在文吕鱼脑泡的发育过程中GATA123和Otx很可能共同发挥着重要的作用.
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用24种限制性内切酶分析了我国21个具代表性地方猪品种、1个引进品种和2个来自中国和越南的野生近缘种mtDNA的RFLP。结果表明:在74个个体中检出的32种限制性态型可归结成7种单倍型,其间的差异主要来源于少数几个限制性位点的点突变;地方猪种4种单倍型间的平均遗传距离为0.143%,遗传多态程度(π值)仅为0.007%,说明遗传多样性非常贫乏,提示中国地方猪种可能起源于一个野猪亚种。
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The centromere protein A (CENP-A), a histone H3-like protein, provides an essential role for chromosomal segregation during mitosis and meiosis. In this study we identified ten new CENP-A-like genes (excluding the original CENP-A gene) in cow by searching
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A total of 36 compounds (1-36) were obtained from the stem bark of Poncirus trifoliata including three new prenylated flavonoids, (-)-5,4'-dihydroxy-7,8-[(3 '',4 ''-cis-dihydroxy-3 '',4 ''-dihydro)-2 '',2 ''-dimethylpyrano]-flavone (1), (-)-5,4'-dihydroxy-7,8-[(3 ''-hydroxy-4 ''-one)-2 '',2 ''-dimethylpyrano]-flavone (2), and (-)-5,4'-dihydroxy-7,8-[(cis-3 ''-hydroxy-4 ''-ethoxy-3 '',4 ''-dihydro)-2 '',2 ''-dimethylpyrano]-flavone (3). The new structures were elucidated by means of spectroscopic methods. Compounds 1-20 were evaluated for their anti-human immunodeficiency virus-1 (HIV-1) activity, in which 2 showed significant anti-HIV-1 activity with high therapeutic index (T1) of 143.65.