937 resultados para 8 chloro 2,3,4,5 tetrahydro 3 methyl 5 phenyl 1h 3 benzazepin 7 ol hydrogen maleate


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The anisotropy of 1.3 - 2.3 MeV protons in interplanetary space has been measured using the Caltech Electron/Isotope Spectrometer aboard IMP-7 for 317 6-hour periods from 72/273 to 74/2. Periods dominated by prompt solar particle events are not included. The convective and diffusive anisotropies are determined from the observed anisotropy using concurrent solar wind speed measurements and observed energy spectra. The diffusive flow of particles is found to be typically toward the sun, indicating a positive radial gradient in the particle density. This anisotropy is inconsistent with previously proposed sources of low-energy proton increases seen at 1 AU which involve continual solar acceleration.

The typical properties of this new component of low-energy cosmic rays have been determine d for this period which is near solar minimum. The particles have a median intensity of 0.06 protons/ cm^(2)-sec-sr-MeV and a mean spectral index of -3.15.The amplitude of the diffusive anisotropy is approximately proportional to the solar wind speed. The rate at which particles are diffusing toward the sun is larger than the rate at which the solar wind is convecting the particles away from the sun. The 20 to 1 proton to alpha ratio typical of this new component has been reported by Mewaldt, et al. (1975b).

A propagation model with κ_(rr) assumed independent of radius and energy is used to show that the anisotropy could be due to increases similar to those found by McDonald, et al. (1975) at ~3 AU. The interplanetary Fermi-acceleration model proposed by Fisk (1976) to explain the increases seen near 3 AU is not consistent with the ~12 per cent diffusive anisotropy found.

The dependence of the diffusive anisotropy on various parameters is shown. A strong dependence of the direction of the diffusive anisotropy on the concurrently measured magnetic field direction is found, indicating a κ_⊥ less than κ_∥ to be typical for this large data set.

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The behavior of the photosensitized cis-trans isomerization of 2,3-diphenylbutene-2 was studied as a function of sensitizer energy by previously established methods. In addition, certain sensitizers for which parameters other than energy transfer are operative in inducting isomerizations, were studied in more detail. Sensitization of various stilbenes and substituted stilbenes by triphenylene is discussed in terms of excited state complex formation with stilbene. Sensitization by quinones, halogen-containing aromatics and 1,2-diketones is discussed in terms of attack by photolytically produced free radicals, either by addition to and elimination from the double bond, or in the cases of 1,2-diphenylpropene and 2,3-diphenylbutene-2, by hydrogen abstraction from one of the methyl groups and reversible abstraction by the allylic radical to produce cis-trans isomerized substrate and the structurally isomerized products, 2,3-diphenylpropene and 2,3-diphenylbutene-1.

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Estudos demonstram a associação de alterações da apolipoproteína E (ApoE) e do receptor do LDL (RLDL) com a ocorrência de doenças cardiovasculares e dislipidemia. O objetivo principal deste trabalho foi investigar a associação entre genótipos diferenciais da ApoE e do RLDL com a persistência de alterações de variáveis lipídicas em indivíduos jovens acompanhados há 28 anos no Estudo do Rio de Janeiro (ERJ). Através de um estudo longitudinal, tipo coorte, investigou-se 56 indivíduos (35M) em três avaliações. Em A1 (13.301.53 anos), A2 (22.091.91 anos) e A3 (31.231.99). Nas três ocasiões foi realizada avaliação clínica. Em A2 e A3 foram dosados colesterol total, HDL, LDL e triglicerídeos. Em A3 acrescentou-se o estudo dos polimorfismos genéticos da ApoE e do RLDL. Os fragmentos de interesse neste estudo foram amplificados por PCR (polymerase chain reaction) e os genótipos foram identificados através de reações de restrição. As frequências genotípicas de ApoE foram ε33 (62,5%), ε3/ε4 (25%), ε2/ε3 (5,4%) ,ε2/ε4 (5,4%) e ε4/ε4 (1,8%) e para os genótipos de RLDL foram AA (85,7%), AT (12,5%) e TT (1,8%). O genótipo ε2/ε2 não foi observado. A análise da distribuição dos genótipos de ApoE segundo a permanência de dislipidemia mostrou que todos os indivíduos com genótipo de ApoE dos tipos ε2/ε4 e ε4/ε4 mantiveram pelo menos um lípide alterado em A2 e A3 entretanto, todos os indivíduos com genótipo de ApoE do tipo ε2/ε3 não apresentaram lípides alterados em A2 e A3. Para o genótipo do RLDL não houve diferença significativa. Quando analisadas isoladamente, não foi identificado nenhum resultado significativo em A2 e/ou A3 associado a estes genótipos. O polimorfismo do gene da ApoE esteve associado à permanência de dislipidemia em indivíduos jovens acompanhados em estudo de seguimento longitudinal

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Este trabajo refleja parte de una ponencia presentada el 27-7-2000 en el marco del curso de arqueología de la Fundación Duques de Soria, dirigido por los profesores G. Ruiz Zapatero y A. Jimeno Martínez.

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被子植物的rRNA基因已经得到深入研究。二倍体被子植物一般拥有1-4对18S-5.8S-26S rDNA位点和1-2对5S rDNA位点。作为特殊的多基因家族成员,rDNA会受均一化力 (homogenizing forces) 的作用,通过基因转换、不等交换等机制,形成基因的致同进化 (concerted evolution)。长期以来,我们一直认为动植物rDNA致同进化水平很高,各种拷贝的序列几乎完全一致,因此可以直接应用PCR测序的方法进行分子系统学研究。但是在裸子植物中由于研究资料的匮乏,使我们对裸子植物rDNA的变异模式了解甚少。松属植物作为裸子植物的最大类群,它的rDNA变异和进化有何特点、与被子植物是否相同,是这个重要类群的进化研究中目前尚未解决的问题。本文的研究内容从三个方面进行: (1)rDNA的染色体定位 目前,松属的18S-5.8S-26S rDNA的染色体定位研究只包括5种植物,其中的3种同时涉及到5S rDNA定位。这些研究结果表明,不同种存在相异的rDNA位点数目,甚至不同的个体的rDNA位点均有变化。其共同点是,18S-5.8S-26S rDNA位点数平均较被子植物多,5S rDNA除Pinus radiata外,在其它种里则与被子植物相似。这种现象是松属或裸子植物的共同特征,亦或是特例呢?有限的研究限制了对裸子植物rDNA的了解。本研究的目的之一就是研究松属植物rDNA的染色体空间分布特征,希望借此了解松属植物间的关系,比较裸子植物和被子植物rDNA在染色体组水平的差异。 (2)5S rDNA的分子进化 5S rDNA的序列水平的进化研究在松属中尚属空白。5S rDNA在染色体数目上没有显示裸子植物与被子植物的差异,是否意味着松属乃至裸子植物的5S rDNA也同被子植物一样——致同进化完全,序列高度一致呢?利用克隆测序方法对松属植物5S rDNA的研究无疑是有开创性的工作,可以探讨裸子植物的5S rDNA的进化机制和种间关系。 (3)杂种基因组研究 杂交物种的起源演化是当前生物学研究的热点,通过杂种基因组的研究,可以了解杂种的的基因组构成,组织方式和进化历史,探讨杂交事件对成种过程的影响及意义。这项研究涉及到高山松、云南松和油松。之所以采用这三种植物,因为等位酶、cpDNA和mtDNA证据证明高山松为油松和云南松的自然杂交种。但这些证据不足以反映杂种核基因组的重组特征和构成及其进化规律。我们利用rDNA-FISH、5S rDNA和基因组原位杂交分析三种松树间的基因组关系,为揭示高山松的进化机制和历史提供新的依据。 本项研究得到以下结果: 一. rDNA荧光原位杂交 (FISH) 通过对华山松和白皮松两种单维管束亚属植物及油松、云南松、高山松、马尾松和南亚松等五种双维管束亚属植物的18S rDNA与5S rDNA的荧光原位杂交,结果表明: ⑴ 裸子植物的18S rDNA位点数目明显多于二倍体被子植物。其中主要位点数目,油松有7对,高山松5对,云南松8对,马尾松10对,南亚松6对,白皮松3对,华山松10对,平均在7对;另外,部分松树还存在弱位点。无论强弱位点都有部分存在于染色体的着丝粒区,除了赤松 (Pinus densiflora),在其它松科植物中并没有发现这种现象。究竟是基因转移的结果或该位点是18S rDNA的原始起源位置还有待确证。 ⑵ 5S rDNA位点相对变异较小,与被子植物相当。除了华山松5S rDNA有4对位点,马尾松只有1对位点外,其它松树的5S rDNA位点数目均为2对,并且在双维管束亚属植物中有一对属于弱位点。 ⑶ 两种rDNA存在不同连锁模式。双维管束亚属植物中,5S与18S rDNA连锁在同一染色体的同一臂或两条臂上。在同一染色体臂时,18S rDNA在臂的远端。单维管束亚属植物的5S与18S rDNA或连锁于同一染色体的同一臂上,或分别处于不同染色体。前一情况,5S rDNA位于臂的远端。据此可以说明两个亚属的rDNA结构在染色体组水平的很大分化。 ⑷ 松属植物的关系及高山松核型特征。由于5S与18S rDNA连锁关系的不同,可以将单维管束亚属和双维管束亚属分开。各亚属的不同物种可以依据杂交位点的多少、位置、信号强弱构成的核型图加以区分,并且构成一定的系统关系。杂交起源的高山松在染色体组上,表现出对油松和云南松两亲本不同染色体特征的分别继承与重组,并产生独有的特征。其II同源染色体之一18S rDNA位点的缺失,可能是染色体重组的痕迹。 二. 5S rDNA的序列变异与分子进化 利用分子克隆和DNA测序分析了油松、云南松、马尾松、白皮松和不同遗传背景的高山松居群的5S rRNA基因序列变异及基因进化规律,得到以下主要结果: ⑴ 5S rDNA的结构特征。双维管束亚属植物长度在658-728 bp,白皮松则为499-521 bp。长度差异体现在基因间隔区,而基因区极端保守,基本为120 bp。基因转录区内部存在着转录控制区,决定了5S rRNA的转录起始与转录效率。5S rRNA基因能够折叠成正常的二级结构,其中,相对于干区来说,环区要保守,但环E却表现出异乎寻常的变异,转换/颠换比值高达7.1,这种突变可能是假基因的产物。基因间隔区存在一定的保守单元,其中一些与转录的起始和终止调控相关,有些是裸子植物未知功能的特异保守区。 ⑵ 松属植物5S rDNA存在着基因组内与种间的异质性。基因组内的各个克隆中有超过80%的特异的,彼此不相同。整个5S rDNA分化距离为0.042 - 0.051,其中,间隔区的分化比基因区高,其速度约是基因区的3-7倍。比较种间5S rDNA序列发现:在122个克隆中,基因区只有50个特异的序列。基因组间的序列变异度与基因组内 (个体内) 没有明显差别。白皮松的间隔区与双维管束亚属松树的5S rDNA间隔区差异极大,几乎不能排序,而四种双维管束亚属植物的5S rDNA间隔区种间种内差异不大。 ⑶ 松属植物5S rDNA进化。PAUP分析建立的5S rRNA基因树显示,5S rRNA基因在基因组内是多系的 (polyphyletic),表明成种事件以前,祖先种就已经存在序列的分化。观测到的5S rRNA基因序列变异状况,并非完全是致同进化或独立进化的单一因素造成的,而是二者的相互作用的结果。致同进化确实存在,只是速度较慢而已。 ⑷ 高山松5S rDNA 组成。高山松拥有最高的基因组内的序列多样性,高山松的5S rDNA拷贝既有亲本类型,又有重组类型,并且不同地理及遗传来源的高山松显示一定的分化趋势,有更多的拷贝来自母系亲本。 三. 基因组原位杂交 以油松和云南松总DNA作为探针,相互进行基因组原位杂交,结果显示云南松和油松的染色体组可以完全被对方探针标记,在现有基因组原位杂交的分辨率下不能将两个基因组区分开。说明云南松和油松基因组之间存在高比例的同源序列,两种松树的基因组组成十分相似。利用油松和云南松总DNA作为探针,对高山松的染色体组进行双探针基因组原位杂交。结果表明,高山松全部基因组都能与两亲本探针完全杂交,说明三者间有着异乎寻常的亲缘关系。但在PH失调影响下,高山松只有部分基因组被杂交,并且两种探针的杂交信号有轻微差异。这可能是高度重复序列优先杂交的结果。这些情况表明,高山松虽然在基因组构成上与两个亲本基本一致,但基因在染色体组的空间排布上是存在差异的,这一点可以从rDNA-FISH中证明。

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植物通过异戊二烯代谢途径合成多种具有生物活性和功能的三萜及甾醇类化合物,它们在调节植物生长发育、维持膜的完整和功能、抵抗病原微生物侵染中发挥着重要的作用。2,3-氧化鲨烯为三萜和甾醇合成途径的分枝点,参与这一关键步骤的酶被通称为2,3-氧化鲨烯环化酶(OSCs)。本研究系统分了水稻基因组中全部11个OSC基因序列,发现其中四个可能为假基因。亚种间非同义替换率Ka和同义替换率Ks的比值(Ka/Ks)以及进化树的分析表明OsOSC8是单子叶植物特有的功能保守基因,而OsOSC9在水稻两个亚种间发生了功能快速进化,这种快速进化的基因往往参与植物和病原菌相互作用的代谢途径。 根据基因结构、表达谱以及与其它植物已知功能的OSC酶氨基酸序列的比对推测OsOSC3可能具有环阿屯醇合成酶的功能,参与植物甾醇的合成,而OsOSC7、OsOSC10和OsOSC11可能具有β-香树素合成酶的功能,其余OSCs可能参与合成其它三萜化合物。为了进一步分析和验证OSCs酶的功能,将水稻7个OSC基因的开放阅读框(ORF)构建到酵母表达载体并在pichia酵母中表达,发现仅有OsOSC9和OsOSC12能够将酵母内源的2,3-氧化鲨烯分别环化为四环三萜化合物Parkeol和植物中稀有的五环三萜化合物Isoarborinol,目前还未在其它植物中发现参与这两种三萜化合物的基因。另外,水稻所有的OSC基因均不能互补酵母羊毛甾醇缺陷型菌株,表明水稻OSCs不具有合成羊毛甾醇的功能。 RNAi沉默以及启动子融合GUS的表达实验发现OsOSC8可能参与花粉的发育,该基因的下调影响水稻的育性,暗示水稻中存在一个可能与雄性不育有关的三萜代谢途径。水稻其它OSC基因RNAi植株可能在逆境环境和病原菌侵染下才会显现出表型。

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One of the most promising prophylactic agents being tested to control Penaeus monodon larval diseases is furanace (6-hydroxymethyl-2 2(5-nitro-2-furyl) vinyl pyridine). To evaluate further its suitability as a chemotherapeutic agent, its effects on the population growth of Chaetoceros calcitrans, the diatom used as feed for the zoeal stages, was examined. Chaetoceros populations of uniform density (initial density in all runs: 130-141x10 SUP-3 cells /ml) were placed in nine white, circular (382 sq cm), plastic basins. The physio-chemical characteristics of the culture water were as follows: salinity, 28 . 5-30 . 0 ppt; pH, 8 . 62-8 . 72; temperature, 23-25 . 5 degree C; dissolved oxygen, 7 . 1-9 . 3 ppm; nitrate, 0 . 03-0 . 07 ppm; and ammonia, 0 . 005-0 . 03 ppm. Preweighed furanace granules were dissolved in the culture water, with resulting concentrations of 1 and 2 mg/l (3 replicates each). A set of replicates without furanace served as the control. Population counts of the diatom were taken after 2, 4, 6, 8, and 10 hr exposures. After 4 hr, the population decreased in all three levels. The population in 2 mg/l furanace showed the lowest count and that in control the highest. The population means are not statistically different from one another. The results of the study show that the furanace causes reductions in Chaetoceros population at all durations of exposure.

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Meeting to develop environmental indicators to measure overall health of BOBLME; identify important coastal water pollution issues: produce conclusions and recommendations to form an action plan.

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由通式(Ⅰ)所示的N-取代基-4-取代苯基-5-烷基-5-取代苄基吡咯烷酮-2类化合物,具有钙拮抗活性,可应用于制备治疗脑功能障碍病药物,早老性痴呆病药物,增强学习记忆药物。其中R1是氢,取代苯甲酰基,1—5个碳原子的链状酰基。R2是氢,1—10个碳原子的正、异构烷基。X是氢,邻、间、对位取代的氟、氯、溴原子或甲氧基、乙氧基。吡咯烷酮-2环上的4,5-二或三取代包括顺式(RS及SR)构型、反式(SS)及RR构型。合成通式(Ⅰ)及其吡咯烷酮-2的方法。通式(Ⅰ)如上。

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The objective of the workshop was the first assessment of marine coastal ecosystems in the BOBLME environment. The workshop: endorsed the report assessing, demonstrating and capturing the economic value of marine & coastal ecosystem services; acknowledged further data was was needed for ecosystem valuation analysis; recommended information from this report be added to the BOBLME Strategic Action Programme; identified economic instruments that might be used in conservation and sustainable management, and proposed future work.

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20038月—20058月,对无量山大寨子5个黑长臂猿群体的结构和组成进行了观察。当一个群体在早晨鸣叫或依次通过树冠时,记录群体的结构和组成。每个群体都由1个成年雄性、2个成年雌性及其后代组成。20038月平均群体大小为6·2只;到20058月,平均群体大小发展为6·4只,其中有2个亚成年雄性从出生群迁出,且有3只幼猿出生。在3个群体(G1、G2和G3)中两个成年雌性都成功繁殖了后代。同一群体内两个成年雌性间无攻击或等级行为。2005年4月15日,当一只亚成年雌性进入G3的领域后,两只成年雌性对其进行追逐驱赶,并且干扰其与成年雄性配合进行二重唱,成年雄性没有直接驱赶流浪的亚成年雌性,10天后这只亚成年雌性离开了G3的领域。亚成年雄性经常与群体其他成员保持一定距离,并且在出生地通过独唱练习鸣叫。黑长臂猿可能通过亚成年雄性和雌性的迁出,及成年雌性对外来流浪雌性的驱赶维持这种一夫二妻的群体结构。

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The objectives of the workshop included: an overview of the biophysical characteristics of the Myeik Archipelago; strengthen understanding of Marine Protected Areas (MPAs) management to mitigate resource use conflicts; share lessons and experiences of MPA management from the Asia-Pacific region; and to identify a road map for developing MPA management in the Myeik Archipelago.

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对从青岚湖采集的 10属 14种河蚌的 19个样本进行了 16SrRNA的序列测定 ,并同GenBank中鄱阳湖流域相同物种河蚌的序列比较 ,分析了基于Kimura 2 parameter模型参数得到的遗传距离 ,并构建了它们的UPGMA树。结果显示 ,所有用于比较的河蚌种间遗传距离变化范围在 0 .0 2 74— 0 .2 2 90 ,平均为 0 .132 5 ,种内遗传距离在0 .0 0 34— 0 .0 0 6 8之间 ,平均为 0 .0 0 4 5 ,种间遗传距离远大于种内距离。表明以 16SrR