47 resultados para 1068


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Iodothyronine plays a major role in growth, basic metabolism and organ formation. It has an extremely limited source in the body. In this thesis, we designed iodothyronine(T4) as hapten. Then a single chain antibody displayed on phange was obtained from a human phage displaying a single chain antibody library. The specific genes of E3 was subcloned in P-5E vector. According to its amino acid sequences, we simulate its three dimention structure by computer. It has never been reported in PDB.

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以四碘甲状腺素原氨酸为半抗原 ,从人噬菌体展示半合成单链抗体库中筛选与半抗原有特异结合性的单链抗体 E3 ,并测定了 E3的一级结构 ,同时用计算机模拟了其空间结构

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本文主要报道一种可用于含过渡金属层状VOP化合物的直接合成方法和用该方法合成的一个新层状乙酰丙酮铜配合物嵌入的磷酸钒(Cu(acac)<,2>-LVPO),并对其进行了结构表征.

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A new mono-substituted titanocene, (eta(5)-cyclopentadienyl) [eta(5)-(1-(4-methoxyphenyl) cyclohexyl) cyclopentadienyl] dichlorotitanium (I), has been prepared via a novel modified synthesis, and its X-ray crystal structure has been determined. It crystallizes in the orthorhombic space group P2(1)2(1)2(1) with cell constants a=0.968 0(5) nm, b=1.284 6(5) nm, c=1.694 4(6) nm, Z=4, R=0.066. The I/methylaluminoxane (MAO) catalyst system produces at different polymerization temperatures either an isotactic or a syndiotactic polypropylene, both of which have the combined influence of enantiomorphic-site control and chain-end control, or an atactic polypropylene controlled by Bernoullian propagation mechanism.

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Poly(acrylonitrile-butadiene-styrene), polycarbonate (PC), and two types of antioxidants have been blended by an extruder twin screw. Notched Izod impact strength, tensile property, and melting flow index (MFI) were measured for the blends including diffe

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[CoCl4(C3H12N2)], M(r) = 276.87, monoclinic, P2(1)/n, a = 10.703 (2), b = 10.653 (1), c = 10.852 (2) angstrom, beta = 118.46 (1)-degrees, V = 1087.8 angstrom 3, Z = 4, D(x) = 1.69 g cm-3, lambda(Mo K-alpha) = 0.71073 angstrom, mu = 22.60 cm-1, F(000) = 556, T = 298 K, final R = 0.059 for 1068 unique reflections [I > 3-sigma(I)]. The Co(II) ion is coordinated by four Cl atoms in a tetrahedral geometry. The paraffinic chains which bridge the tetrahedra have a nearly planar zigzag configuration.

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本文提出用碳酸氢铵和镧作基体改进剂的衬钽管石墨炉原子吸收光谱测定钪的方法,灵敏度是热解管的19倍左右,无记忆效应,测定精度好,抗干扰能力强,原子化温度大大降低,管子寿命可达600多次。本法不需预分离直接测定土壤,沉积物标样中的钪,结果与参考值基本吻合。

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Penicillium herquei isolate GA4 was isolated from the infected Conchocelis of Porphyra yezoensis. A large-scale fermentation using yeast extract sucrose medium and repeated chromatography afforded a new symmetrical urea derivative, hualyzin (1). The structure was determined by detailed NMR spectroscopic investigations and MS fragmentation analysis.

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Arginine kinase (AK) was previously reported as a phosphagen-ATP phosphotransferase found in invertebrates. In this study, an 1184 bp cDNA was cloned and sequenced. It contained an open reading frame of 1068 bp that coded for 356 deduced amino acids of AK in Fenneropenaeus chinensis. The calculated molecular mass of AK is 40129.73 Da and pI is 5.92. The predicted protein showed a high level of identity to known AK in invertebrates and creatine kinase from vertebrates, which belong to a conserved family of ATP:guanidino phospho-transferases. In addition, AK protein in plasma of F. chinensis was identified using two-dimensional electrophoresis (2DE) and electrospray ionization mass spectrometry (ESI-MS) according to the calculated molecular mass and pI. AK was significantly decreased in the plasma of F. chinensis at 45 min and recovered at 3 It after laminarin injection as confirmed by 2DE and ESI-MS. The results showed that AK was one of the most significantly changed proteins on two-dimensional gel in the plasma proteins of F. chinensis at 45 min and 3 It after simulation. (c) 2005 Elsevier Ltd. All rights reserved.

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The South China Sea (SCS) is one of the most active areas of internal waves. We undertook a program of physical oceanography in the northern South China Sea from June to July of 2009, and conducted a 1-day observation from 15:40 of June 24 to 16:40 of June 25 using a chain of instruments, including temperature sensors, pressure sensors and temperature-pressure meters at a site (117.5A degrees E, 21A degrees N) northeast of the Dongsha Islands. We measured fluctuating tidal and subtidal properties with the thermistor-chain and a ship-mounted Acoustic Doppler Current Profiler, and observed a large-amplitude nonlinear internal wave passing the site followed by a number of small ones. To further investigate this phenomenon, we collected the tidal constituents from the TPXO7.1 dataset to evaluate the tidal characteristics at and around the recording site, from which we knew that the amplitude of the nonlinear internal wave was about 120 m and the period about 20 min. The horizontal and vertical velocities induced by the soliton were approximately 2 m/s and 0.5 m/s, respectively. This soliton occurred 2-3 days after a spring tide.

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微型和小型底栖动物是底栖微/小食物网的重要构成。相对浮游生态系统, 迄今国际间对底栖食物网的认知极为欠缺。这一方面是由于微型生物形态和功能上的复杂性和多样性, 另一方面原因在于研究方法的障碍—主要是微型和小型底栖动物的定量提取和定性分析。本研究首先进行了方法学改良, 并应用新方法对底栖微食物网的重要功能类群—纤毛虫原生动物和小型底栖动物进行了不同生境的周年按月采样, 定性及定量研究的同时, 联系环境因子对微型和小型底栖生物的环境监测进行了探讨。 微型和小型底栖生物的定量研究首先涉及到目标生物在沉积物中的有效提取, 目前硅胶液提取是普遍使用的方法, 其中Ludox液主要应用于小型生物, 它不但价格便宜而且比重合适, 因此在常规生态研究中被广为接受。不过, Ludox易与于海水中的阳离子产生凝结而无法直接用于微型生物; 目前唯一直接应用于微型生物提取的是Percoll硅胶液, 但其昂贵的价格使其在常规生态研究中受到极大限制。本研究以价格低廉的Ludox 硅胶液结合定量蛋白银染色 (QPS) 技术开发了一种新的方法, 即Ludox-QPS法。主要流程为: 样品采集与固定、淘洗/稀释降盐、Ludox密度梯度离心、过滤浓缩和琼脂包埋, QPS染色、永久封片及鉴定计数。添加已知数量的纤毛虫至无生物底泥的重获实验表明, 该密度梯度离心的提取率大于94%; 该方法对自然沉积物中纤毛虫的提取率达97.6%, 对沙质、泥沙质和泥质中海洋线虫的提取率分别达97%、96.9% 和97.8%。对比实验表明, 经QPS制片获得的小型动物的丰度和类群数量与传统方法相当或更高, 尤其当小个体虫体占优势时, 该法显示出较传统方法 (导致数量低估) 更为明显的定量优越性。该方法除用于纤毛虫和小型动物的定量分析外, 还具有较高的分类分辨率, 染色后的纤毛虫原生动物大多类群可鉴定到属, 部分可鉴定到种, 以此可在群落水平上研究其生态作用。 根据新开发的Ludox-QPS技术, 在大沽河潮间带依据盐度梯度选定2个站位 (IIQ和营海) 进行了周年按月采样, 对底栖纤毛虫和小型底栖动物进行了定量研究。纤毛虫原生动物在IIQ和营海的年平均丰度分别为2236 inds./10 cm2 和935 inds./10 cm2 (28 inds./ml 和12 inds./ml), 平均生物量分别为119.1 gC/10 cm2和54.2 gC/10 cm2 (1.5 gC /ml 0.7 gC/ml)。丰度的季节变化趋势为: 春天 > 秋天 > 夏天 > 冬天。垂直分布上, 在营海分布于表层0-0.5 cm 的比例为57.1%, 分布于0.5-2 cm、2-4 cm和4-8 cm比例分别为23.1%、11.4% 和8.5%; 13个月中除12月份外, 4-8 cm均有一定数量的纤毛虫分布; 而在IIQ, 97% 的纤毛虫分布在0-0.5 cm, 分布在0.5-2 cm、2-4 cm和4-8 cm比例分别为2.4%、0.4%和0.2%, 4-8 cm的分布只发生在春季和秋季。纤毛虫的多样性季节变化明显, 春秋季物种丰富, 两个站点每毫升沉积物的平均物种数分别为18和6。Two-Way Crossed ANOSIM 分析表明纤毛虫群落在月份间和站点间的差异极其显著。Pseudochilodonopsis sp., Chilodontopsis sp., Euplotes sp.及Prorodon sp.是表征两个生镜中纤毛虫群落的主要类群。 同时, 发现了14个小型生物类群, 其中线虫在IIQ和营海的丰度优势度分别为97.4% 和78.6%。小型动物在IIQ和营海的年平均丰度分别为4793 inds./10 cm2和8915 inds./10 cm2 (60 inds./ml和111 inds./ml), 其生物量分别为1068.8 gC /10 cm2和1790 gC /10 cm2 (13.4 gC/ml和22.4 gC/ml)。小型底栖动物的丰度在IIQ的季节变化为: 夏季 (7888 inds./10cm2) > 秋季 (5447 inds./10cm2) > 春季 (3731 inds./10cm2) > 冬季 (2780 inds./10cm2); 在营海则完全相反: 冬季 (15579 inds./10cm2) > 春季 (10691 inds./10cm2) > 秋季 (6611 inds./10cm2) > 夏季 (4667 inds./10cm2)。小型底栖动物和纤毛虫的相对重要性存在明显的区域和季节差异。 纤毛虫原生动物、小型动物及环境因子的相关分析表明, 纤毛虫的丰度和多样性与温度和盐度及有机质含量显著相关, 与小型动物没有显著相关性; 群落结构分析表明, 温度、有机质和小型动物的丰度的组合与纤毛虫群落丰度的相关系数为0.345; 盐度、脱镁叶绿素、有机质和小型动物生物量的组合与纤毛虫群落多样性的相关系数为0.403。依据海洋线虫和桡足类的比值 (N/C) 推测, IIQ 可能存在严重的有机污染, 营海则存在明显的季节波动, 8月和9月及2月可能是污染最严重的季节, 这种状况在纤毛虫群落结构的CLUSTER聚类中得到验证。虽然目前尚没有形成有关微型底栖生物-纤毛虫原生动物的污染检测的直接依据, 但本研究说明纤毛虫群落的确对环境污染具有一定的感应度, 而且这种感应和利用小型生物的主要类群估算的污染检测 (N/C) 存在一定程度的关联。 90年代早期有关青岛湾有机污染带的研究表明, 经彻底截污后, 其环境状况向良性发展。进一步了解该湾的健康状况, 2006.5-2007.5月对该湾沙质和泥沙质的小型动物进行周年按月采样。小型动物在泥沙质和砂质沉积物中的年平均丰度分别为4853 ± 1292 inds./10 cm2和1528 ± 569 inds./10 cm2; 年平均总生物量分别为1434.1 ± 897.0 gC /10cm2和720.7 ± 353.8 gC/10cm2。沙质底小型生物的丰度季节波动明显, 6月份和12月份最高, 3月份和9月份最低; 泥沙质季节波动不明显, 6月份最高。两个站点均有48%的小型动物分布在0-0.5 cm 表层, 海洋线虫在表层的分布比例分别为48% (泥沙质) 和34% (砂质)。共检获14个小型动物类群, 其中线虫在泥沙质和砂质沉积物中的年平均丰度分别4619 ± 1255 inds./10cm2和1014 ± 376 inds./10cm2, 其丰度优势度分别为95.2%和66.4%。其它在丰度上占优势的类群, 泥沙质依次为多毛类 (1.5%)、甲壳幼体 (1.5%) 和桡足类 (0.7%); 沙质依次为: 甲壳类幼体 (12.6%)、腹毛类 (8.3%) 和 桡足类 (6.2%)。CLUSTER聚类分析表明, 泥沙质和和砂质中小型生物的丰度组成具有64%的相似性。BIOENV分析表明, 温度、盐度、中值粒径和粘土粉砂含量的组合最能解释不同月份之间和不同站位间的差异, 其相关系数为0.614。依据小型生物的丰度和类群组成, 表明泥沙质底尚存一定的有机污染。

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近年来,分子生物学技术与方法被越来越多地应用于有害赤潮研究。其中,单细胞PCR方法是对难以室内培养的有害赤潮藻种进行遗传特征研究的一项重要技术。本实验尝试建立微藻的单细胞PCR方法,并将其应用于鳍藻研究。 应用室内培养的亚历山大藻,研究了微藻的单细胞PCR方法,并对藻细胞的固定和保存方法进行了比较。结果表明,浮游植物研究中常用的甲醛固定方法只能用于短期保存样品(少于5天),而乙醇固定、鲁格氏液固定、或者在-20℃下冷冻保存的样品,在较长的时间后(60天)仍可以得到比较理想的PCR扩增结果。 应用单细胞PCR方法,对青岛近海采集的鳍藻进行了研究,扩增并测定了包括核糖体大亚基(LSU)rDNA的5’端D1-D2区序列,以及5.8S rDNA和ITS区的部分序列信息。通过分析软件对所得到的鳍藻序列信息与基因库中已知的鳍藻序列信息进行了分析与对比。根据ITS和LSU序列信息构建的系统进化树都显示,本文采集的鳍藻藻种与国外报道的圆形鳍藻聚为一支,初步确定采集的鳍藻应为圆形鳍藻,对该藻种形态学特征的观察也支持这一结果。该藻种部分LSU rDNA序列与欧洲同种鳍藻相似度达到99%,与其它等鳍藻遗传距离在18%-20%之间。测定的ITS区序列与同种圆形鳍藻有62个碱基的差异,与LSU rDNA序列相比,ITS序列变异更大。应用LC-MS方法对该鳍藻的进行了DSP毒素分析,结果未检测到OA或DTX1毒素。 这是我国首次应用单细胞PCR方法对鳍藻开展的研究工作,首次报道了我国鳍藻的核糖体部分序列信息。圆形鳍藻在青岛近海海域是初次报道,显示了单细胞PCR方法在鳍藻研究中的重要意义。

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牙鲆在中国北方沿海地区形成了大规模的工厂化养殖,成为我国海水养殖的一大重要产业。然而疾病的频繁发生严重阻碍了这一产业的发展,为了保证牙鲆产业稳定、健康、持续地发展,开展鱼类免疫系统的基础研究,提高鱼类抵抗病原菌侵害的能力,本研究从牙鲆免疫系统的个体发育过程入手,克隆了其rag(recombination activating gene)基因,在此基础上对其组织特异性表达进行了分析。 研究结果表明牙鲆rag1基因由4个外显子和3个内含子组成,第一个外显子位于5’非翻译区,这一外显子存在两种不同的剪切方式。牙鲆rag1基因编码1068个氨基酸。牙鲆rag2基因的编码区序列长为1602 bp,编码533个氨基酸,没有在牙鲆rag2基因编码区内发现内含子的存在。rag基因间序列长为3128 bp,两个基因共用一段3’非编码区。 本试验通过RT-PCR检测发现,牙鲆的rag1和rag2基因在头肾和体肾中均有表达。整装原位杂交结果表明,牙鲆在受精后第8天开始起有rag1和rag2基因的表达,主要在胸鳍前面,腮背部的部位表达,这个区域与后来胸腺出现的位置相一致。冰冻切片结果显示,rag是在靠近咽部的区域有表达。石蜡切片原位杂交结果显示,rag基因在胸腺中的表达显示出不均一性,着色较深的为皮层区,而着色比较浅的为髓部。 将牙鲆rag1基因的一部分(编码559个氨基酸)和rag2全基因序列(编码533个氨基酸)插入到表达质粒pProEXTM HTa上,在大肠杆菌E. coli BL-21中进行体外表达与分析,结合BD TALONTM Metal Affinity Resins亲和柱纯化了RAG2蛋白。

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Ecological and physiological features of the planktonic copepod Calanus sinicus in the southern Yellow Sea in summer were studied to reveal its life history strategy. From the coastal shallow waters to the central part of the southern Yellow Sea, a shift of the stage composition occurs from being dominated by the egg-nauplius stage to being dominated by the fifth copepodite (CV) stage. Most CVs reside in the Yellow Sea Cold Water Mass (YSCWM), where both temperature and food abundance are low. CVs in the YSCWM have longer body lengths, heavier body weights and higher carbon contents than those outside the YSCWM. Onboard incubations show that the development of CVs in the YSCWM is suspended. Energy conservation, development suspension and lack of diel vertical migration (DVM) behavior suggest a diapause status for the CVs in the YSCWM, although vertical distribution patterns indicate the CV individuals are not fully synchronous in physiology and development. This adaptive oversummering strategy would help C. sinicus to live through the warm and food-limited summer in the central part of the southern Yellow Sea; both low temperature and low food supply are necessary for CV to maintain the resting state in the YSCWM. Calanus sinicus exhibits different life history strategies in different regions of the southern Yellow Sea in summer.

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To investigate the ecological effect of macroalgae on de-eutrophication and depuration of mariculture seawater, the variation of dissolved inorganic nitrogen (DIN) and phosphate (DIP), the amount of Vibrio anguillarum, and total heterotrophic bacteria in Ulva clathrata culture, as well as on the algal surface, were investigated by artificially adding nutrients and V. anguillarum strain 65 from February to April 2006. The results indicated that U. clathrata not only had strong DIN and DIP removal capacities, but also showed a significant inhibitory effect on V. anguillarum, although not reducing the total heterotrophic bacteria. Vibrio anguillarum 65 dropped from 5 similar to 8 x 10(7) cfu mL(-1) to 10 cfu mL(-1) (clone-forming units per mL) in 10 g L-1 of fresh U. clathrata culture within 2 days; i.e., almost all of the Vibrios were efficiently eradicated from the algal culture system. Our results also showed that the inhibitory effect of U. clathrata on V. anguillarum strain 65 was both DIN- and DIP-dependent. Addition of DIN and DIP could enhance the inhibitory effects of the algae on the Vibrio, but did not reduce the total heterotrophic bacteria. Further studies showed that the culture suspension in which U. clathrata was pre-cultured for 24 h also had an inhibitory effect on V. anguillarum strain 65. Some unknown chemical substances, either released from U. clathrata or produced by the alga associated microorganisms, inhibited the proliferation of V. anguillarum 65.