134 resultados para 613.907
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稀土羧酸配合物中,羧基配位方式是个有兴趣的问题。羧基采取单配位、螯合配位、对称桥式配位或单原子桥式(或螯合桥式)配位的那些方式,不但与稀土离子和羧酸结构,而且与配合物制备条件有关。不少研究发现某些配合物中,羧基可以同时存在多种配位方式。用振动光谱研究羧基的配位方式和配合物结构已引起广泛兴趣。环已烷酸(以下用HL和L分别代表酸及其阴离子)与稀土的配合物研究尚少,我们合成了它的十六种稀土的1∶3无水配合物,通过红外和拉曼光谱研究了羧基在各稀土配合物中的配合方式,配位多面体结构及配位键性质。
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Genetic differentiation of the shrimp Penaeus chinensis in the Yellow Sea and Bohai Sea was investigated using the mitochondrial control region (CR). RFLP of a partial CR segment (613 bp) shows that 106 out of 122 (86.9%) individuals from six sampling localities along the coast of northern China and the west coast of the Korean Peninsula share the same haplotype, and the haplotype frequencies among localities are not significantly different. The findings are further confirmed by sequencing the complete CR. Divergence of the complete CR (992 bp) is less than 1.6% in 14 individuals from the six localities. F-statistics based on RFLP data and the TCS network of sequencing data suggest little genetic differentiation of P. chinensis in the Yellow Sea and Bohai Sea. Mismatch analysis suggests a rapid expansion of P. chinensis population to the Yellow Sea and the Bohai Sea, which probably occurred with the rapid rise in sea level after the last glacial maximum. Despite the lack of genetic heterogeneity, we propose that P. chinensis populations in this region should be treated as separate management units, as fishery management programs have to be applied on a local basis by different governments.
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贝类养殖作为我国传统的海水养殖产业,在我国沿海地区的经济发展中起重要作用。但由于近年来养殖扇贝病害的不断发生,不仅造成了巨大的经济损失,而且直接威胁到现有养殖产业的生存和发展。目前认为,机体抗病能力的下降是发生流行性死亡的主要原因之一。因此,深入研究扇贝免疫防御特性,能更好地了解和解决贝类养殖中的病害问题。本文比较了健康状态和重金属污染以及高温胁迫下海湾扇贝和栉孔扇贝部分免疫指标的变化,并对同龄不同大小的栉孔扇贝的部分免疫指标进行了比较,以期更好的了解贝类的防御机制,为扇贝病害防治提供资料。研究结果如下: 用流式细胞仪技术对血细胞死亡率、细胞吞噬率和呼吸爆发进行了测定,发现健康状态下两种扇贝的细胞死亡率相差不大,海湾扇贝为4.83%,栉孔扇贝为4.95%;细胞吞噬率差异显著(P<0.05),海湾扇贝为26.73%,栉孔扇贝为19.89%;呼吸爆发的基础值相差也不大,海湾扇贝为1.94,栉孔扇贝为1.56。另外用免疫化学方法对健康状态下栉孔扇贝和海湾扇贝血淋巴和肝胰腺中SOD、ACP活性和MDA含量也进行了测定与比较。发现在血淋巴和肝胰腺中,两种扇贝SOD活性均存在显著差异(P<0.05),其中海湾扇贝分别为995.43和113.99,栉孔扇贝分别为446.64和40.6;血淋巴和肝胰腺中ACP活性差异显著(P<0.05),海湾扇贝分别为90.19和432.36,栉孔扇贝分别为73.26和146.63;血淋巴中和肝胰腺中MDA含量差异不显著(P>0.05),海湾扇贝分别为3.37和92.46,栉孔扇贝分别为2.17和28.96。实验结果说明,海湾扇贝对细菌等异物的吞噬和杀灭能力以及机体自身的抗氧化能力高于栉孔扇贝,这为海湾扇贝比栉孔扇贝具有更高的抗逆性提供了证据。 用相同的方法对不同浓度(0, 0.2, 0.3, 0.5 mg L-1) Pb2+溶液浸泡后的栉孔扇贝和海湾扇贝的血细胞死亡率、细胞吞噬率和呼吸爆发进行了检测,同时测定了Pb2+处理后肝胰腺中SOD、ACP活性和MDA含量的变化。结果表明,栉孔扇贝的血细胞死亡率与对照组相比有上升趋势,且随着Pb2+浓度的增加而显著增加,而海湾扇贝在相同条件Pb2+的胁迫下,血细胞的死亡率明显低于栉孔扇贝。栉孔扇贝各实验组细胞吞噬率均低于对照组,而海湾扇贝在低浓度的Pb2+浸泡后,细胞的吞噬率与对照组相比有所降低,但随着浓度的继续增加,细胞的吞噬率反而上升,甚至略高于对照组。栉孔扇贝血细胞的呼吸爆发在Pb2+胁迫后较对照组有所升高,但随着浓度的增加,呼吸爆发有下降的趋势,而海湾扇贝的呼吸爆发随着Pb2+浓度的增加而显著增加。对两种扇贝体液免疫指标的测定发现,各实验组SOD的活性均比对照组高,且海湾扇贝的SOD活性高于栉孔扇贝;随着Pb2+浓度的增加,各实验组ACP的活性一直呈上升趋势,且海湾扇贝的ACP活性也高于栉孔扇贝;Pb2+处理后MDA的含量均显著增加,其中栉孔扇贝MDA含量的增幅明显高于海湾扇贝。该结果说明,Pb2+对两种扇贝的免疫系统都有一定的影响,但相同剂量的Pb2+对两种扇贝的毒害程度不同,海湾扇贝对Pb2+的耐受性似乎高于栉孔扇贝。 对海湾扇贝和栉孔扇贝的升温刺激实验发现,当养殖水体的温度从18℃缓慢升高到30℃后,栉孔扇贝在第三天开始出现大量死亡现象,而海湾扇贝未出现死亡。因而本文只对升温前后的海湾扇贝进行了细胞死亡率、吞噬率和呼吸爆发的测定和比较。结果发现,与升温前相比,血细胞的死亡率在温度升高后略有增加,但差异不显著(P>0.05);而细胞吞噬率在温度升高后显著下降;通过对呼吸爆发积聚的活性氧(Reactive Oxygen Species,ROS)的测定发现,升温后血细胞的ROS含量显著高于升温前(P<0.05)。该结果表明,高温会影响血细胞的功能,使机体的免疫防御能力下降,从而导致病害的发生。 另外,本文对同龄不同大小的栉孔扇贝的血细胞吞噬率以及血淋巴和肝胰腺中SOD、ACP活性和MDA含量进行了测定与比较。结果发现: 小扇贝的血细胞吞噬率略高于大扇贝,分别达到了22.82和20.96;在血淋巴及肝胰脏中,两组扇贝SOD酶的活性均差异显著(P<0.05),小扇贝分别为613.88和102.01,大扇贝分别为356.15和50.22;血淋巴中小扇贝ACP的活性极显著的高于大扇贝(P<0.01),分别为44.3和2.91,但肝胰腺中大扇贝和小扇贝ACP的活性相差不大,大扇贝为455.75,小扇贝为485.33;大扇贝和小扇贝血淋巴和肝胰脏中MDA含量相差不大,大扇贝分别为2.67和31.83,小扇贝分别为3.17和35.33。该结果说明,小扇贝对细菌等异物的吞噬和杀灭能力以及机体自身的抗氧化能力高于大扇贝,这为生长与抗逆性相颉抗提供了依据。
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本文对藻蓝蛋白复合物保护化学性肝损伤的功效学进行了研究。以Wistar大鼠建立酒精性肝损伤模型,将藻蓝蛋白复合物分为高、中、低三个剂量组,以联苯双酯作为阳性对照组,灌胃给药42d,分别测定血清谷丙转氨酶(ALT)、谷草转氨酶(AST)、血清丙二醛(MDA)、谷胱甘肽(GSH)、肝匀浆丙二醛(MDA)和谷胱甘肽(GSH)的含量,并对肝脏切片进行病理检查。结果表明:藻蓝蛋白复合物对血清ALT、AST具有显著的抑制作用,显著拮抗肝脏MDA的升高,显著提高肝脏GSH-Px含量。出现肝细胞浊肿、脂肪变性、点状坏死的大鼠数目极少。从而表明藻蓝蛋白复合物具有显著的保护酒精性肝损伤的功效。
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选用全糯小麦品种‘糯麦1号’与青海主要栽培品种‘阿勃’杂交,综合利用改良碘染色法、SDS-PAGE法和Waxy基因的分子标记等,对杂交后代进行了鉴定筛选。最终从F2代鉴定出了5粒全糯种子,从F_代鉴定出8株Wx-B1亚基缺失的植株。对全糯株系F_3代的农艺性状进行评价,5个全糯株系的综合农艺性状都优于‘糯麦1号’,与‘阿勃’较接近。测定全糯株系和Wx-B1亚基缺失植株F_4代种子的直链淀粉含量,5个全糯株系F_4代种子的直链淀粉含量接近于0,8个Wx-B1亚基缺失植株F_4代种子的直链淀粉含量在总 体上比‘阿勃’的直链淀粉含量低。研究表明,采用综合标记辅助选择可快速而准确地获得适合在青海栽培的全糯和部分糯性小麦。
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生物多样性与生态系统功能的关系及其机制是生态学领域的重大科学问题.人们越来越关注环境因子对多样性-生产力关系的影响.植物群落组成、物种丰富度、物种特征、生物量的分布结构和植物枯枝落叶对高寒草甸物种多样性和生产力有着重要的影响.因此,我们利用2001~2004年中国科学院海北生态系统定位站高寒草甸群落的实测资料,研究了不同环境梯度(土壤含水量和营养)下,植物群落生物量,物种丰富度及组成的变化.结果表明,植物群落物种组成的不同反应在生物量的分布上,以藏嵩草为优势种的藏嵩草沼泽化草甸群落总生物量(地上、地下)最高(13196.96±719.69g/m~2),次之是以杂类草和莎草科为主的小嵩草草甸(2869.58±147.52g/m~2),以禾本科和杂类草为主的矮嵩草草甸最低(2153.08±141.95g/m~2).藏嵩草沼泽化草甸中,草本植物枯枝落叶显著高于小嵩草、矮嵩草草甸,土壤含水量对草本植物枯枝落叶有较大的影响.不同类型草甸群落中,地上生物量与土壤有机质、全氮和群落盖度之间均呈显著正相关(P〈0.05);藏嵩草沼泽化草甸中,总生物量与物种丰富度呈负相关(rs=-0.907,P〈0.05)、地下生物量与土壤含水量呈正相关(rs=-0.900,P〈0.05);而在小嵩草和矮嵩草草甸中它们之间均没有达到显著水平,说明不同类型高寒草甸群落生产力除受物种多样性、功能群内物种密度和均匀度的影响,同时也受物种本身特征和外部环境资源的影响.不同类型草甸群落生物量的分布与土壤含水量和土壤养分的变化相一致.
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性比是反映动物种群的基本特征之一,因此成为种群生态学的主要研究内容。就种群的性比而言,在不同的物种、或同一物种在不同的时期和条件下都有极大的不同~[1-4]。性比的改变将影响动物的种群结构、家庭组成和交配关系,也影响动物两性的配偶竞争、繁殖投入、繁殖成功以及性二型的分化等~[4-13]。在繁殖过程中,动物可以采用改变性比的方法调节种群的密度和大小[2,14,15]。同时,动物的性比受多种因素的影响,不仅存在季节、年间以及地理变化的差异,而且受环境条件(如气温和降水量)的影响~[2~4]。捕食风险也是影响性比的主要因素。虽然许多动物出生时的性比是一样的,但是,由于捕食者在捕食猎物的过程中存在明显的选择性,使其性比发生了明显的变化~[16]。对于动物种群性比的研究已有诸多报道,其研究的动物包括海蛇尾(Ophiactis savignyi)~[5]、龙虾(Homarus gam- marus)~[6]、射毒蛙(Dendrobates purnilio)~[9]、斑马雀(Taeniopygyia guttata castanotis)~[8]、褐家鼠(Rattus norvegicus)~[17]等。高原鼠兔(Ochotona curzoniae)是青藏高原草地生态系统中的优势小哺乳类动物。有关高原鼠兔种群性比的研究,国内学者有过涉及~[18,19],但所作工作多是在高原鼠兔繁殖生态学研究中进行的静态描述,对种群性比的年龄变化,季节和年度变化及其与环境条件的关系等方面的研究尚缺详细的报道。本文通过对高原鼠兔种群性比的年间比较、不同胎次性比的分析和越冬对其性比影响的研究,旨在探讨高原鼠兔的性比变化在其种群调节中的作用。
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珠毛蟹甲草 ( Parasenecio roborowskii)是菊科千里光族中款冬亚族蟹甲草属的一种植物 ,在藏药上全草入药 ,有治疗哮喘等疾病之功效。本文首次观察了珠毛蟹甲草的大小孢子发生、雌雄配子体的发育 ,旨在为开发与利用该种植物提供有性生殖过程方面的基础资料。
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The dissertation focuses on the petrology, geochemistry of the volcanic rocks in east Tibet and southeast Yunnan. It lucubrates the Magmatic process, forming mechanism and the possible tectonic settings of the volcanic rocks. The volcanic rocks of Nangqen basin in east Tibet, Qinghai province are mainly Cenozoic intermediate-acid shoshonites. The rocks are LREE enriched and the LREE/HREE = 3~34; (La/Yb)_N = 18.17-53.59, and ΣREE 222~1260μg/g. There are no Eu anomaly, and Nb, Ta, Zr, Hf, Ti are markedly depleted. The isotopic composition is ~(87)Sr/~(86)Sr = 0.70497~0.70614, ~(206)Pb/~(204)Pb = 18.622~18.974, ~(208)Pb/~(204)Pb = 38.431~38.996, ~(207)Pb/~(204)Pb = 15.511~15.613, respectively. K-Ar age of the whole rocks and the single mineral are between 32.0-36.5Ma. Based on the trace elements and isotopic elements, we get the conclusion that the partial melting is one of the dominated forming mechanisms for the volcanic rocks in Naneqen basin. The magma did not experience the crustal contamination en route to the surface; however, the complex mixture took place in the upper mantle before the melt was formed. There are at least two kinds of mixed sources that can be identified. The basalt in southeast Yunnan province is studied. They are distributed in Maguan, Tongguan, and Pingbian County, which is located on the both sides of the Red River belt, and the ultrabasic xenolith are cursory introduced. The volcanic rocks belongs to the alkali series, which can be subdivided into trachybasalt and basanite(Ol normal molecule >5). The volcanic rocks are characteristics by high Ti and low Mg#. According to the magma calculation model, the original rocks of the basalt in southeast Yunnan province are Spinel Lherzolite in Tongguan, Garnet Lherzolite in Pingbian and Maguan, while Togguan undergoes 2-5 percent and percent of partial melting, whereas volcanism in Maguan and Pingbian was so complex to calculate. The fractional crystallization took place during the magma evoltion in southeast Yunnan. The basalt is enriched in LREE with LREE/HREE=9.23-20.19. All of the trace elements display weak Nb, Ta peak, and the depletion of Zr, Hf and Ti in Maguan and pingbian represent the presence of Garnet in the source. The composition of the isotope ratio are ~(87)Sr/~(86)Sr = 0.70333-0.70427, ~(143)Nd/~(144)Nd = 0.512769-0.512940, ~(206)Pb/~(204)Pb = 18.104-18.424, ~(207)Pb/~(204)Pb = 15.483 -15.527; ~(208)Pb/~(204)Pb = 37.938-38.560, respectively, which shows the characteristics of the HIMU type OIB. The volcanic rocks of the southwest Yunnan are derived from the enriched, OIB type mantle sources by synthesizing all the data from trace and isotope elements. It is similar to that of the volcanic rocks in Hawaii, a typical kind of the mixtures of the recycled oceanic crust plume and depleted asthenosphere. To sum up, the volcanic rocks in southeast Yunnan are formed by the intraplate hotpot volcanism.
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:本文对含金石英脉中流体包裹体进行了研究,结果表明主阶段石英中流体包裹体均一温度为122~306℃ ,存在两个区间分别为130~22O℃、250~270℃ ,均一温度在水平和垂直方向存在规律性变化,盐度主要集中在3% ~8%NaCl范围内,密度为0 80~0.95 c ,流体包裹体具有相对稳定的气液比,流体包裹体气液相成分与典型的岩浆水和大气降水不同。结合氢氧锶和稀有气体同位素研究,认为墨江金矿成矿流体曾发生过部分地幔流体、大气降水等多种类型水不充分的混合,水岩反应和多种流体混合可能为墨江金矿矿质迁移沉淀主要机制。结 合哀牢山金矿带成矿流体类似性和流体包裹体特征分析认为墨江金矿深部可能存在有含金石英脉型矿体。
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在西昆仑北缘早前寒武纪变质地层中,笔者等识别出大量不同时代的片麻状花岗岩,其中包括新元古代片麻状花岗岩。获得最新的新元古代片麻状花岗岩的单颗粒锗石SHRIMP年龄为815±57Ma,片麻状花岗岩的岩石学特征反映它们形成于裂解构造背景,结合对区域上新元古代地层及中元古代末期构造事件的研究,笔者认为新元古代片麻状花岗岩反映了古塔里木板块作为Rodinia超大陆一员发生裂解的时间,这对研究古塔里木板块在Rodinia超大陆中的位置及中国Rodinia超大陆裂解的研究提供了重要的地质依据。
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A resurgence of interest in the human plasma proteome has occurred in recent years because it holds great promise of revolution in disease diagnosis and therapeutic monitoring. As one of the most powerful separation techniques, multidimensional liquid chromatography has attracted extensive attention, but most published works have focused on the fractionation of tryptic peptides. In this study, proteins from human plasma were prefractionated by online sequential strong cation exchange chromatography and reversed-phase chromatography. The resulting 30 samples were individually digested by trypsin, and analyzed by capillary reversed-phase liquid chromatography coupled with linear ion trap mass spectrometry. After meeting stringent criteria, a total of 1292 distinct proteins were successfully identified in our work, among which, some proteins known to be present in serum in < 10 ng/mL were detected. Compared with other works in published literatures, this analysis offered a more full-scale list of the plasma proteome. Considering our strategy allows high throughput of protein identification in serum, the prefractionation of proteins before MS analysis is a simple and effective method to facilitate human plasma proteome research.