16 resultados para CR863.009 A663s


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1、KMBZ-009 改善高台应激所致认知障碍和应激相关的抑郁样行为及其相关机理 研究。 虽然适当的应激会提高动物的学习记忆功能,但过量的应激特别是无法逃避 的应激,往往导致依赖海马或前额叶的学习记忆功能受损,这与应激改变脑内应 激激素(皮质酮,皮质醇等)和神经递质的释放,影响突触传递和可塑性(包括 长时程增强和长时程抑制,LTP 和LTD)有关。一些疾病的发生、发展和恶化, 比如抑郁症(Depression)、创伤后应激障碍(PTSD),往往也和应激相关联,其 神经化学基础被证实与内分泌系统和单胺类(如五羟色,去甲肾上腺素,多巴胺) 神经递质系统的功能密切相关。遗憾的是,到目前为止还没有发现能治疗应激的 药物。本实验室过去的研究证实:KMBZ-009(申报新药时的名称为芬克罗酮,英 文名Phenchlobenpyrrone)——一种新的取代吡咯烷酮类化合物,通过调节细胞 内钙,改变脑内神经递质的释放,从而影响脑高级功能。KMBZ-009 对神经递质 释放影响是否能减轻应激导致的认知障碍及应激相关疾病的发生还没有进行研 究。本研究采用Morris 水迷宫、行为操作箱、绝望游泳、膜片钳和活体电生理 技术研究了KMBZ-009 对高台应激所致认知障碍和应激相关的抑郁样行为的影响 及其相关机理。 研究结果发现,高台应激或皮质酮注射造成大鼠空间记忆提取障碍,这与其 导致的海马CA1 区突触可塑性改变有关,而KMBZ-009 能成剂量依赖性地逆转应 激对空间记忆提取的损伤作用,这与它阻断应激或皮质酮异化的LTD 和恢复应激 或皮质酮损伤的LTP 密切相关。KMBZ-009 能部分地降低因应激而升高的血清皮 质酮含量,此外,KMBZ-009 对大鼠海马CA1 区锥体神经元的兴奋和抑制电流的 影响可能也参与了其对应激的调节作用。KMBZ-009 能显著增加海马CA1 区锥体 神经元上AMPA 受体介导的兴奋性突触后电流(EPSC)的幅度,但不影响其动力 学特性。NMDA 受体介导的EPSC 不受KMBZ-009 的影响;GABA 受体介导的抑制突 触后电流(IPSC)的幅度几乎不受KMBZ-009 的影响,而其受体动力学特性明显 被KMBZ-009 改变,表现为IPSC 恢复的时间显著延长。KMBZ-009 对CA1 区兴奋 抑制电流的调节作用,使大鼠海马细胞具有更强的维持细胞稳态的能力,从而避免应激导致神经元功能的损害。KMBZ-009 对抗应激对认知得损伤作用提示其可 能会减少动物的抑郁样行为,本实验结果发现,KMBZ-009 确实能明显减少小鼠 在强迫游泳(FST)中的不动时间,增加大鼠在72 秒低频差式强化(DRL-72s) 模型中的强化率,并降低其反应率。其机制是KMBZ-009 增加正常动物中枢神经 系统胞外NE 水平,激活alpha 和beta 肾上腺素受体,从而使得实验动物的抑郁 样行为明显减少。 2、KMBZ-009 减轻氧化应激对细胞活力、线粒体电位及海马LTP 的损伤作用。 前人的研究表明,氧自由基过多是导致老年痴呆患者和老年人神经细胞凋亡 与认知障碍的因素之一。KMBZ-009 和阿尼西坦是吡咯烷酮类化合物,研究显示 均具有促智作用。有报道指出阿尼西坦能减少神经胶质细胞在缺血缺氧时氧自由 基的生成,从而避免细胞受到氧应激损伤。本研究采用神经元原代培养和离体电 生理学方法,观察了KMBZ-009 和阿尼西坦对氧应激神经元的保护作用。结果发 现,KMBZ-009 和阿尼西坦均能保护氧应激神经元的线粒体的功能,对抗氧自由 基对神经元细胞活力的损伤,从而有效逆转了氧化应激对海马脑片CA1 区LTP 的 损伤作用。KMBZ-009 的作用效果比阿尼西坦的效果强10 倍。 3、银杏叶提取物及复方制剂改善老年大鼠空间学习记忆的突触可塑性机理。 有研究表明,银杏叶和三七叶提取物能调节神经系统的功能。本研究采用 Morris 水迷宫和活体电生理技术研究了银杏三七复方制剂及银杏叶提取物(以 标准银杏叶提取物——金纳多作为阳性对照药)改善老年大鼠空间学习记忆障碍 的突触可塑性机理研究。结果发现:老年大鼠空间学习记忆能力较差,高频诱导 不能在其海马CA1 区引发LTP,当长期服用金纳多或复方制剂一个月后,老年动 物的空间学习记忆功能得到明显改善,这可能与药物增强海马LTP 有密切关系。 复方制剂的作用效果与金纳多的效果相当。 4、悬尾应激损伤避暗作业学习行为的多巴胺D1 受体机制。 近年来的研究表明,DA 系统对应激非常敏感,应激改变PFC 内DA 的含量, 从而导致依赖于PFC 的工作记忆受损。但目前尚不知道应激对DA 系统的影响是 否涉及依赖杏仁核和海马的情绪学习记忆功能。因此,我们采用被动回避作业和 行为药理学的方法,初步探讨了此问题。结果发现:和对照组动物相比,随着悬 尾应激持续时间的增加(5min、10min、20min),动物在避暗作业作业重测试中的步入潜伏期明显缩短,当动物被悬尾应激后回到鼠笼中休息20min,其步入潜 伏期无明显变化;腹腔注射DA D1 受体拮抗剂SCH23390 呈剂量依赖性地缩短动 物的步入潜伏期,但SCH23390 腹腔注射和悬尾应激共同处理实验动物时,此种 D1 受体拮抗剂能有效逆转应激对步入潜伏期的影响;进一步的研究发现,应激 或D1 受体拮抗剂对痛觉感受的影响不是其改变动物步入潜伏期的主要因素。本 研究结果表明悬尾应激导致脑内多巴胺释放过度增加,杏仁核(可能还有海马及 相关神经回路)内的D1 受体被过度激活,从而导致小鼠在操作被动回避任务时 的记忆获得障碍。

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Numerical simulations were conducted to study thermocapillary flows in short half-zone liquid bridges of molten tin with Prandtl number Pr = 0.009, under ramped temperature difference. The spatio-temporal structures in the thermocapillary flows in short half-zone liquid bridges with aspect ratios As = 0.6, 0.8, and 1.0 were investigated. The first critical Marangoni numbers were compared with those predicted by linear stability analyses (LSA). The second critical Marangoni numbers for As = 0.6 and 0.8 were found to be larger than that for As = 1.0. The time evolutions of the thermocapillary flows exhibited unusual features such as a change in the azimuthal wave number during the three-dimensional stationary (non-oscillating) flow regime, a change in the oscillation mode during the three-dimensional oscillatory flow regime, and the decreasing and then increasing of amplitudes in a single oscillation mode. The effects of the ramping rate of the temperature difference on the flow modes and critical conditions were studied as well. In this paper, the experimental observability of the critical conditions was also discussed. (C) 2008 Elsevier Inc. All rights reserved.

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实验采用壳聚糖和聚合氯化铝改性高岭土,进行以铜绿微囊藻为优势种的水华蓝藻去除的比较研究.研究采用动力学手段,通过去除效率的比较,得到线性方程:壳聚糖改性高岭土投加量(y)与藻细胞浓度OD680(x)和叶绿素a含量(x)之间的关系分别为:y=0.0349x-0.0019、y=0.0524x-0.009;聚合氯化铝改性高岭土投加量(y)与藻细胞浓度OD680(x)和叶绿素a含量(x)之间的关系分别为:y=0.0351x+0.0065、y=0.0676x-0.0059.壳聚糖改性粘土除藻的最适pH范围为5-8,

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桃花水母属一些种类命名的有效性仍存在争议,本文建立了两个新的形态度量学参数,即触手密集度和平衡囊密集度,采用形态度量学方法对在我国采集到的索氏桃花水母、嘉定桃花水母、中华桃花水母和短手桃花水母进行了比较研究,并讨论这两个参数在种类区分上的应用。此外,利用Spearman秩相关系数检验桃花水母各形态学参数之间的相关性。结果表明,短手桃花水母和中华桃花水母在形态上没有明显的差异,可能与中华桃花水母为同一物种。嘉定桃花水母与中华桃花水母和索氏桃花水母在形态上均存在显著的差异,应该是一个有效种。桃花水母的触手数和

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The objective of this study was to illustrate the phylogenetic relationship of the species in the genus Craspedacusta in China. The medusae samples were collected at 28 localities in China representing seven described species with their entire ITS region (the contiguous sequences of ITS-1, 5.8S and ITS-2 rDNA) rDNA sequences cloned. Among the 28 samples, the range of sequence variation in the complete ITS and 5.8S region was between 0 and 36.2%. Three main clades were revealed by both maximum likelihood and neighbour-joining trees, with sequence difference of 0-0.9, 0-3.7 and 0.1-1.5% in the three clades. The nesting of C. xinyangensis representatives within C. sowerbii, C. brevinema within C. sinensis and C. sichuanensis within C. kiatingi is strongly supported, with interspecific sequence divergence of 0-0.9, 0.1-1.4 and 0.0-0.4%, respectively. Thus, it is suggested that C. xinyangensis should be the synonym of C. sowerbii, C. sichuanensis the synonym of C. kiatingi and C. brevinema the synonym of C. sinensis. However, the taxonomic status of C. ziguiensis is still uncertain. According to the tree topology, C. kiatingi was closer to C. sowerbii than to C. sinensis. Craspedacusta sinensis was the most genetically distinct from distance matrix values, and located at the base of the phylogenetic trees, so it can be speculated that the C. sinensis may be the ancestral form in the genus Craspedacusta.

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The concentrations of major anions and cations, nitrogen and phosphorus, dissolved and particulate trace elements, and organic pollutants were determined for the middle and lower reaches of the Yangtze River (Changjiang) from below the Three Gorges Dam (TGD) to the mouth at Shanghai in November 2006. The concentration of dissolved inorganic phosphate (DIP) was constant at a low level of 6-8 mu gP/L, but the concentration of nitrate (NO3-) approximately doubled downstream and was closely correlated with K+. This translated to a daily load of well over 1000 It of dissolved inorganic nitrogen (DIN) at Datong. The average concentrations of dissolved Pb (0.078 +/- 0.023 mu g/L), Cd (0.024 +/- 0.009 mu g/L), Cr(0.57 +/- 0.09 mu g/L), Cu (1.9 +/- 0.7 mu g/L), and Ni (0.50 +/- 0.49 mu g/L) were comparable with those in other major world rivers, while As (3.3 +/- 1.3 mu g/L) and Zn (1.5 +/- 0.6 mu g/L) were higher by factors of 5.5 and 2.5, respectively. The trace element contents of suspended particles of As (31 +/- 28 mu g/g), Pb (83 +/- 34 mu g/g), and Ni (52 +/- 16 mu g/g) were close to maximum concentrations recommended for rivers by the European Community (EC). The average concentrations of Cd (2.6 +/- 1.6 mu g/g), Cr (185 +/- 102 mu g/g), Cu (115 +/- 106 mu g/g), and Zn (500 +/- 300 mu g/g) exceeded the EC standards by a factor of two, and Hg (4.4 +/- 4.7 mu g/g) by a factor of 4 to 5. Locally occurring peak concentrations exceed these values up to fourfold, among them the notorious elements As, Hg, and Tl. All dissolved and particulate trace element concentrations were higher than estimates made twenty years ago [Zhang, J., Geochemistry of trace metals from Chinese river/estuary systems: an overview. Estuar Coast Shelf Sci 1995; 41: 631-658.]. The enormous loads of anthropogenic pollutants disposed to the river were diluted by the large water discharge of the Yangtze even during the lowest flow resulting in the relatively low concentration levels of trace elements and organic pollutants observed. We estimated loads of e.g. As, Pb and Ni to the East China Sea to be about 4600 kg As d(-1), 3000 kg Pb d(-1), and 2000 kg Ni d(-1). About 6000 t d(-1) of dissolved organic carbon (DOC) was delivered into the sea at the time of our cruise. We tested for 236 organic pollutants, and only the most infamous were found to be barely above detection limits. We estimated that the load of chlorinated compounds, aromatic hydrocarbons, phenols, and PAHs were between 500 and 3500 kg d(-1). We also detected eight herbicides entering the estuary with loads of 5-350 kg d(-1). The pollutant load, even when at low concentrations, are considerable and pose an increasing threat to the health of the East China Sea ecosystem. (c) 2008 Elsevier B.V. All rights reserved.

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每种酸碱指示剂在其变色PH范围内都有一个明显的颜色变化,在其相应的PH-A曲线上总存在一段直线部分,通过选择一定PH变色范围和适当浓度的指示剂,就能使各指示剂PH-A曲线上的直线部分相互迭加成一条新的直线,从而加宽了混合指示剂的表现变色PH范围,依此原理,本论文以二种流动注射分析方法独立地完成了工艺流程中高浓定影液酸度的在线分析。并对这二种方法做了简单的对比。(一)工艺流程中高浓定影液酸度的在线分析方法研究(1)我们选择了内含0.08%溴甲酚紫,0.04%溴百里酚兰,0.02%甲酚红组成的混合指示剂的6%稀释液作为试剂,以C-41CX定影浓缩液作载流,用F2A-分光光度法完成了高浓度定影液酸度的在线测定,相对标准偏差在50.2%以内,采样频率为100次/h,分析周期很短(25秒),在5.5~8.0PH范围内,PH-A工作曲线具有很好的线性关系,相关系数0.9996,斜率即灵敏度达到:0.198A/PH。(二)工艺流程中高浓定影液酸遮掩在线分析方法研究(2)我们造反了0.005%的溴甲酚紫,0.009%的溴百里酚兰和0.025%的甲酚红作为混合酸碱指示剂,以蒸馏水作载流,通过选择最佳测定条件用流动注射-分光光度法(F2A-Spectrophotometry)在线测定了不宜用其它分析法测定的高浓溶液的酸度。该分析方法还可以推广到其它高浓溶液的酸度的在线测定。相对误差在±0.2%以内;分析周期为30秒;采样体积为60μL。在5.2~8.5PH范围内,混合指示剂的PH-A工作曲线具有良好的线性关系,相关系数达到0.9991,工作曲线斜率即是灵敏度达到0.376A/PH。

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An augmented immersed interface method (IIM) is proposed for simulating one-phase moving contact line problems in which a liquid drop spreads or recoils on a solid substrate. While the present two-dimensional mathematical model is a free boundary problem, in our new numerical method, the fluid domain enclosed by the free boundary is embedded into a rectangular one so that the problem can be solved by a regular Cartesian grid method. We introduce an augmented variable along the free boundary so that the stress balancing boundary condition is satisfied. A hybrid time discretization is used in the projection method for better stability. The resultant Helmholtz/Poisson equations with interfaces then are solved by the IIM in an efficient way. Several numerical tests including an accuracy check, and the spreading and recoiling processes of a liquid drop are presented in detail. (C) 2010 Elsevier Ltd. All rights reserved.

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Reducing uncertainties in the estimation of land surface evapotranspiration (ET) from remote-sensing data is essential to better understand earth-atmosphere interactions. This paper demonstrates the applicability of temperature-vegetation index triangle (T-s-VI) method in estimating regional ET and evaporative fraction (EF, defined as the ratio of latent heat flux to surface available energy) from MODIS/Terra and MODIS/Aqua products in a semiarid region. We have compared the satellite-based estimates of ET and EF with eddy covariance measurements made over 4 years at two semiarid grassland sites: Audubon Ranch (AR) and Kendall Grassland (KG). The lack of closure in the eddy covariance measured surface energy components is shown to be more serious at MODIS/Aqua overpass time than that at MODIS/Terra overpass time for both AR and KG sites. The T-s-VI-derived EF could reproduce in situ EF reasonably well with BIAS and root-mean-square difference (RMSD) of less than 0.07 and 0.13, respectively. Surface net radiation has been shown to be systematically overestimated by as large as about 60 W/m(2). Satisfactory validation results of the T-s-VI-derived sensible and latent heat fluxes have been obtained with RMSD within 54 W/m(2). The simplicity and yet easy use of the T-s-VI triangle method show a great potential in estimating regional ET with highly acceptable accuracy that is of critical significance in better understanding water and energy budgets on the Earth. Nevertheless, more validation work should be carried out over various climatic regions and under other different land use/land cover conditions in the future.

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A new kind of polyfluorene copolymers, poly(2,7-(9,9-dioctyl-fluorene)-alt-5,5 -(4',7'-di-2-thienyl-2',1',3',-benzothiadiazole) (PFDTBT), was prepared. The introduction of ZnO nanoparticles with perfect wurtzite crystal character into PFDTBT makes the resulted single-layer photovoltaic device to perform a significant photovoltaic response. Among the tested devices, the best performance is observed for that containing 60 wt% of ZnO nanoparticles, which has a photocurrent density of 1.17 mu A/cm(2), an open circuit voltage of 0.81 V. a fill factor of 0.09 and a power conversion efficiency of 0.009%. The results show that the polyfluorene derivatives/ZnO nanoparticles hybrid composites are excellent fluorescence and photovoltaic materials. (C) 2009 Elsevier B.V. All rights reserved.

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A new kind of polyfluorene copolymers, poly(2,7-(9,9-dioctyl-fluorene)-alt-5,5 -(4',7'-di-2-thienyl-2',1',3',-benzothiadiazole) (PFDTBT), was prepared. The introduction of ZnO nanoparticles with perfect wurtzite crystal character into PFDTBT makes the resulted single-layer photovoltaic device to perform a significant photovoltaic response. Among the tested devices, the best performance is observed for that containing 60 wt% of ZnO nanoparticles, which has a photocurrent density of 1.17 mu A/cm(2), an open circuit voltage of 0.81 V. a fill factor of 0.09 and a power conversion efficiency of 0.009%. The results show that the polyfluorene derivatives/ZnO nanoparticles hybrid composites are excellent fluorescence and photovoltaic materials.

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采用石墨炉原子吸收光谱法测定蘑菇中的镉、铅,以磷酸二氢铵和硝酸镁作混合基体改进剂,提高了测定的灰化温度,消除了基体干扰。方法简便,快速,准确度高。镉和铅的相对标准偏差为3.7%~6.0 %和7.3 %~7.9%;回收率为 98%~106%和 98%~104%;检出限为0.009μg g和0.032 μg g。

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Sargassum muticum is important in maintaining the structure and function of littoral ecosystems, and is used in aquaculture and alginate production, however, little is known about its population genetic attributes. In this study, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers were used to investigate the genetic structure of four populations of S. muticum and one outgroup of S. fusiforme (Harv.) Setchell from Shandong peninsula of China. The selected 24 RAPD primers and 19 ISSR primers amplified 164 loci and 122 loci, respectively. Estimates of genetic diversity with different indicators (P%, percentage of polymorphic loci; H, the expected heterozygosity; I, Shannon's information index) revealed low or moderate level of genetic variations within each S. muticum population, and a high level of genetic differentiations were determined with pairwise unbiased genetic distance (D) and fixation index (F-ST ) among the populations. The Mantel test showed that two types of matrices of D and F-ST were highly correlated whether from RAPD (r = 0.9706, P = 0.009) or ISSR data (r = 0.9161, P = 0.009). Analysis of molecular variance (AMOVA) was conducted to apportion the variations among and within the S. muticum populations. It indicated that variations among populations were higher than those within populations, being 55.82% verse 44.18% by RAPD and 55.21% verse 44.79% by ISSR, respectively. Furthermore, the Mantel test suggested that genetic differentiations among populations were related to the geographical distances (r > 0.6), namely, conformed to the IBD (isolation by distance) model, as expected from UPGMA (unweighted pair group method with arithmetic averages) cluster analysis. On the whole, the high genetic structuring among the four S. muticum populations along the distant locations was clearly indicated in RAPD and ISSR analyses (r > 0.9, P < 0.05) in our study.

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Genetic variation of four populations of Sargassum thunbergii (Mert.) O. Kuntze and one outgroup of S. fusiforme (Harv.) Setchell from Shandong peninsula of China was studied with random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. A total of 28 RAPD primers and 19 ISSR primers were amplified, showing 174 loci and 125 loci, respectively. Calculation of genetic diversity with different indicators (P%, percentage of polymorphic loci; H, the expected heterozygosity; I, Shannon's information index) revealed low or moderate levels of genetic variations within each S. thunbergii population. High genetic differentiations were determined with pairwise Nei's unbiased genetic distance (D) and fixation index (F-ST) between the populations. The Mantel test showed that two types of matrices of D and FST were highly correlated, whether from RAPD or ISSR data, r=0.9310 (P = 0.008) and 0.9313 (P=0.009) respectively. Analysis of molecular variance (AMOVA) was used to apportion the variations between and within the S. thunbergii populations. It indicated that the variations among populations were higher than those within populations, being 57.57% versus 42.43% by RAPD and 59.52% versus 40.08% by ISSR, respectively. Furthermore, the Mantel test suggested that the genetic differentiations between the four populations were related to the geographical distances (r > 0.5), i.e., they conformed to the IBD (isolation by distance) model, as expected from UPGMA (unweighted pair group method with arithmetic averages) cluster analysis. As a whole, the high genetic structuring between the four S. thunbergii populations along distant locations was clearly indicated in the RAPD and ISSR analyses (r > 0.8) in our study.