995 resultados para 7140-332


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利用CO_2激光对YBa_2Cu_3O_(7-Y)块材进行熔凝处理后,证明可逆反应式YBa_2Cu_3O_(7-Y)(?)Y_2Cu_2O_5+4BaCuO_2成立,在结构上消除了孔洞等缺陷,使晶粒细化均匀,有序化程度及致密度提高,有效地提高了材料的临界电流密度J_c,从而提出用CO_2激光制备高温超导体YBa_2Cu_3O_(7-y)超导体块材、带材及线材实用化的新工艺.

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Clip domain serine protease (cSP), characterized by conserved clip domains, is a new serine protease family identified mainly in arthropod, and plays important roles in development and immunity. In the present study, the full-length cDNA of a cSP (designated EscSP) was cloned from Chinese mitten crab Eriocheir sinensis by expressed sequence tags (ESTs) and PCR techniques. The 1380 bp EscSP cDNA contained a 1152 bp open reading frame (ORF) encoding a putative cSP of 383 amino acids, a 5'-untranslated region (UTR) of 54 bp, and a 3'-UTR of 174 bp. Multiple sequence alignment presented twelve conserved cysteine residues and a canonical catalytic triad (His(185), Asp(235) and Ser(332)) critical for the fundamental structure and function of EscSP. Two types of cSP domains, the clip domain and tryp_spc domain, were identified in the deduced amino acids sequence of EscSP. The conservation characteristics and similarities with previously known cSPs indicated that EscSP was a member of the large cSP family. The mRNA expression of EscSP in different tissues and the temporal expression in haemocytes challenged by Listonella anguillarum were measured by real-time RT-PCR. EscSP mRNA transcripts could be detected in all examined tissues, and were higher expressed in muscle than that in hepatopancreas. gill, gonad, haemocytes and heart. The EscSP mRNA expression in haemocytes was up-regulated after L anguillarum challenge and peaked at 2 h (4.96 fold, P < 0.05) and 12 h (9.90 fold, P < 0.05). Its expression pattern was similar to prophenoloxidase (EsproPO), one of the components of crab proPO system found in our previous report. These results implied that EscSP was involved in the processes of host-pathogen interaction probably as one of the proPO system members. (C) 2009 Elsevier Ltd. All rights reserved.

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The effects of infection of EGFP-expressing Escherichia coli on the haemocytes of the ascidian Ciona intestinalis were investigated. The results showed that THC of the infected individuals changed significantly. Hyaline amoebocytes phagocytosed E. coli in 5 min and excreted lysosome particles that attached to the surface of the bacteria. Granular amoebocytes released lots of particles for Immoral immunity while stem-cell-like haemocytes remained intact. With the increase in THC, the stem-cell-like haemocytes showed division and proliferation. A small portion of hyaline amoebocytes was at early apoptosis stage I h after infection and typical apoptosis bodies emerged in granular amoebocytes. A few of the infected haemocytes showed DNA damage using SCGE assay. Flow cytometry analysis revealed an obvious apoptosis peak in infected haemocytes. In conclusion, apoptosis was found to be an important immune response of ascidian haemocytes response to bacterial infection. To our best knowledge, this is the first report of the occurrence of apoptosis of haemocytes in ascidians. (c) 2005 Elsevier B.V. All rights reserved.

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We explore the tectono-magmatic processes in the western West Philippine Basin, Philippine Sea Plate, using bathymetric data acquired in 2003 and 2004. The northwestern part of the basin formed through a series of northwestward propagating rifts. We identify at least five sequences of propagating rifts, probably triggered by mantle flow away from the mantle thermal anomaly that is responsible for the origin of the Benham and Urdenata plateaus. Gravitational forces caused by along-axis topographic gradient and a similar to 30 degrees ridge reorientation appear to also be driving the rift propagations. The along-axis mantle flow appears to be reduced and deflected along the Luzon-Okinawa fracture zone, because the spreading system remained stable west of this major fault zone. North-east of the Benham plateau, a left-lateral fracture zone has turned into a NE-SW-trending spreading axis. As a result, a microplate developed at the triple junction.

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遗传力是数量遗传学的重要参数,对鱼类良种选育具有重要意义。可靠的遗传力估计值可以为合理制定育种计划提供宝贵信息,同时可以预测选择反应。本文按照10×3因子设计方法,10尾雄鱼与3尾雌鱼两两授精,产生10个父系半同胞、3个母系半同胞及30个全同胞家系,以微卫星分子标记为家系鉴定手段,对40日龄牙鲆生长相关性状遗传力进行了估计;同时,初步探讨了因子交配设计及人工控制条件下,亲本对子代遗传贡献率差异及有效群体大小。主要结论包括:1.初步筛选的14个微卫星位点中,有9个(Po91、Po1、Po56、Po20、Poli23、Po89、Poli121、Po42、Po13)在亲本中呈现中、高度多态性:平均等位基因9.4个;平均亲本特异性等位基因4个。用5个位点(Po91、Po1、Po56、Po20、Poli23)为346个子代中的227个个体找到所属家系;继续用另外4个位点(Po89、Poli121、Po42、Po13)分型,成功鉴定72个个体。鉴定率约86%,其中,亲本特异性等位基因的存在使鉴定效率大大提高。以上9个位点可为该群体良种选育工作提供技术支持。2. 发生降解的DNA与完整的DNA,在相同引物、相同PCR体系、相同模板浓度下扩增的带型一致。该结果证实了微卫星分型对降解的DNA同样稳定。3. 亲本对子代的遗传贡献率存在差异。雄亲的贡献率为5.8—14.3%,除3号、9号子代数较少,5号、6号子代数较多外,其它父本基本一致;母本对子代的贡献率差异较大(18.5%—50.6%),这与人工授精前雌亲发育状况、卵子质量检测结果基本一致,在一定程度上说明,母本尤其是卵子质量对鱼类早期存活具有较大影响。4. 家系内子代数目的不平衡导致实际有效群体大小下降。Ne=7.44,比理论有效群体大小(9.23)下降约19%。但与自然交配相比(有效群体下降可达75%),人工控制下的交配在一定程度上可有效限制遗传多样性的下降。5. 基于父本方差组分,40日龄生长相关性状遗传力估计值(h2s±S.E.)为(0.157±0.052)-(0.440±0.137)。加性遗传方差在表型方差中所占的比例,在一定程度上表明该牙鲆群体生长性状具有一定的选择力度。

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第一部分 刺参遗传连锁图谱的构建 利用AFLP和微卫星标记以一个远缘地理杂交家系为作图群体,以拟测交理论为作图策略,构建了刺参Apostichopus japonicus的雌性和雄性遗传连锁图谱。利用62对AFLP引物组合,对亲本和93个个体进行了分离分析,共得到3572个标记,其中具有多态性的标记为点数为1133个,多态性比例为31.5%。平均每个引物对产生18.3个多态片段。1133个多态性位点中,294个标记在父母本中都出现并在后代中分离,839个标记在父本或母本中出现并在子代分离,其中母本443(52.8%)个分离标记,父本396(47.2%)个分离标记。卡方检验显示,556个标记符合孟德尔1:1分离。筛选微卫星标记中30个在家系中具有作图信息,其中19个可用于母本作图,19个可用于父本作图。 利用Mapmaker 3.0/EXP软件对分离标记进行连锁分析。358个分子标记用于雌性遗传连锁分析,其中包括19个微卫星标记,199个AFLP标记和11个微卫星标记定位在雌性框架图谱中。雌性框架图谱共有25个连锁群,总长度为3148.3 cM。标记之间最大间隔为37.5 cM,平均间隔为17.0 cM,连锁群的分子标记数最大为21个最小为4个。用于雄性连锁分析的分子标记共有332个,其中包含19个微卫星标记。207个标记定位于23个连锁群上,其中AFLP标记数为196个,微卫星标记数为11个。23个连锁群总长度为3059.8 cM,标记间最大间隔38.6 cM,平均间隔16.6 cM。每个连锁群的长度范围在40 cM到271.4 cM之间,标记数在18到4个之间,包括二、三连体在内的雄性连锁图谱共覆盖3227 cM。雌雄基因组的预测长度分别为4053.7 cM和3816.3 cM,因此,所构建的雌雄连锁图谱覆盖率分别为84.0%和84.5%。通过共有微卫星标记,有3个连锁群在两个图谱中对应。分子标记在两个图谱中呈均匀分布,没有成簇现象。 分子标记筛选、遗传图谱的构建为刺参分子标记辅助选择育种,经济性状QTL定位和比较基因作图打下基础,并且最终将促进中国刺参遗传改良和新品种的培育工作。 第二部分 卵母细胞成熟过程研究 对刺参卵母细胞的体外诱导成熟方法进行探索,并且通过透射电子显微镜、扫描电子显微镜和激光共聚焦显微镜结合超薄切片技术及间接免疫荧光染色技术研究卵母细胞成熟的生物学过程。 分别利用在海参中有诱导作用的海星神经提取液和二硫苏糖醇(DTT)对从成熟卵巢解剖出的刺参卵母细胞进行诱导成熟试验,结果显示,刺参的卵母细胞在海水中不会发生自发成熟,海星神经提取液以及神经提取液加滤泡悬浮液对卵母细胞没有诱导成熟的作用,而二硫苏糖醇处理可以诱导卵母细胞生发泡破裂,当DTT溶液的浓度处于10-1 mol/L到10-3 mol/L之间时,对刺参卵母细胞的促熟作用较为明显,在10-2 mol/L左右时,卵母细胞的诱导成熟率可以达到90%以上。未成熟的卵母细胞处于第一次减数分裂前期,不具备受精能力。经DTT诱导后,生发泡发生移动并破裂,染色体排列到赤道板上,然后第一、二极体先后排出,诱导成熟的卵母细胞排出极体的时间与自然受精的卵子一致。在卵母细胞成熟过程中有受精膜举起的现象,说明精子入卵不是受精膜举起的必要条件。卵母细胞只有在生发泡破裂之后才具有受精能力,从生发泡破裂到第二极体排出前的整个减数分裂过程中,卵母细胞都可以受精,但是只有在第一极体排出前受精的卵母细胞才能发生卵裂。人工促熟的卵母细胞受精后,形成的胚胎似乎并不能正常发育,试验过程中最多只得到了8细胞期的胚胎,之后细胞便产生畸形并停止分裂,最终裂解消失。 利用DTT诱导刺参卵母细胞成熟,综合运用光镜、电子显微镜及激光共聚焦技术观察卵母细胞成熟过程,分析了卵母细胞表面动物极突起在卵母细胞脱滤泡中的作用,以及卵母细胞动物极突起和微管组织在生发泡移动过程中所起的作用。卵母细胞通过动物极突起连接到滤泡上,在脱滤泡作用开始时,卵母细胞动物极突起刺入并穿过滤泡膜,使得滤泡膜表面形成一个缺口,然后整个卵母细胞开始从缺口处挤出。脱滤泡的作用力来源有两种:胶膜层的水合作用以及滤泡的收缩。通过激光共聚焦显微镜观察,未成熟的卵母细胞中存在5种类型的微管,并且有两个微管组织中心锚定在卵母细胞突起下方。减数分裂重新启动时,生发泡沿微管向动物极移动,至细胞膜下时破裂。微管解聚对照实验证明驱动生发泡移动的细胞结构为微管束。生发泡破裂后,两个微管组织中心组织形成减数分裂纺锤体,然后第一极体以“收缩-排出”的独特方式排出。 本研究填补了刺参繁殖生物学研究中的缺失环节,为刺参人工繁育技术提供理论基础和指导。

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目的:研究塞隆骨提取物对弗氏完全佐剂诱导活化的腹腔巨噬细胞的免疫抑制作用。方法:小鼠腹腔注射弗氏完全佐剂诱导腹腔巨噬细胞活化并回收,体外加入LPS及IFN-γ刺激培养巨噬细胞,利用酶联免疫法测定培养上清中细胞因子(IL-1β、IL-6、IL-12p40、TNF-α水平。结果:塞隆骨水提物及90%醇沉部分体内给药均能够能显著抑制弗氏完全佐剂诱导的巨噬细胞向腹腔的浸润,能抑制巨噬细胞在LPS及IFN-γ刺激下生成细胞因子(IL-12p40、IL-1β、IL-6、TNF-α。结论:塞隆骨提取物对巨噬细胞功能有一定程度的影响,能够抑制其产生炎症因子,可能是其治疗类风湿性关节炎的作用机理之一。

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目的建立了青海地区唐古特大黄药材的HPLC指纹图谱.方法采用反相高效液相色谱法,乙腈-水(0.04%的磷酸)为流动相,梯度洗脱,体积流量1.0 mL/min,检测波长为280 nm,柱温为40 C.结果精密度、重现性、稳定性试验中共有峰面积和保留时间的RSD均小于5%.青海不同采集地唐古特大黄的平均相似度为0.925.结论该方法简便、实用、可靠,可用于以青海果洛地区为主产地不同海拔唐古特大黄药材质量标准的分析检测,也为栽培大黄代替野生大黄提供理论基础.

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对高寒草甸藏嵩草 (Kobresiatibetica)种群的繁殖对策进行了初步研究 .结果表明 :藏嵩草属寒冷中生密丛短根茎地下芽植物 ,在高寒生境中采用了以营养繁殖为主、有性繁殖为辅的繁殖策略 ,具体体现在以下几个方面 :藏嵩草种子产量nA=2 0 0 .1m-2 ,但种子萌发率较低 ,室内和野外萌发率分别仅有 4%和 2 % ,经氢氧化钠溶液和赤霉素溶液处理后的种子萌发率分别为 1%和 6 .7% ,而剥去种皮后种子萌发率达 47.3% ,所以种皮坚硬是造成种子萌发率低的主要原因 ;进入种子库、保留至返青期且具有活性的种子仅占种子总数的 31.49% ;单位面积上理论实生苗数仅为1.2 6m-2 ,与此相反 ,藏嵩草营养繁殖所形成的新个体数为 10 1.32m2 ,远远多于种子萌发所形成的实生苗数 .此外 ,藏嵩草营养繁殖效力也远高于有性繁殖效力,营养繁殖效力占总繁殖效力的83.46%(167)。

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本文提出一种基于遗传算法的轨迹规划方法,以解决操作臂的动态轨迹优化问题,并且结合智能发育的方法进行学习和训练,以保证算法的实时性,较好的解决了操作臂的实时轨迹规划问题。

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The Sawuer gold belt is located in the transition belt between Siberian plate and Kazakhstan-Junggar plate. Based on the geological and geochemical studies on the Kuoerzhenkuola and Buerkesidai gold deposits, in Sawuer gold mineralization belt, the time-space structure of mineralization and mineralizing factor are studied, the metallogenic regularity is concluded in thistheses. The ore bodies have the regularity that orebody are of the extensive and compressive in the sallow and depth of volcanic apparatue, respectively, and the vertical extension of orebody is more intensive than the horizontal extension. The gold deposits were controlled by the fractures of volcanic apparatus and regional faults, and featured by the hydrothermal alteration and metasomatism type disseminated mineralization and filling type vein mineralization. By virtue of the geological and geochemical studies on the two deposits that the formation of the two deposits are significantly related to the volcanic activity, we propose new ideas about their origin: (1) the two deposits are located in the same strata, and share the same genesis. (2) both of two deposits are volcanogenic late-stage hydrothermal gold deposits. Based on mapping of volcanic lithofacies and structure for the first time, it is discovered that a volcanic apparatus existed in the study area. Volcanic-intrusive activity can be divided into three cycles and nine lithofacies. where the two deposits are hosted in the same volcanic cycle, in this case, the wall-rock should belong to the same strata. The 40Ar-39Ar age method is employed in this work to analyze the fluid inclusions of quartz in the ore bodies from Kuoerzhenkuola and Buerkesidai gold deposits. The results show that the main mineralization occurred in 332.05 + 2.02-332.59 + 0.5IMa and 335.53 + 0.32Ma~336.78 + 0.50Ma for Kuoerzhenkuola and Buerkesidai gold deposits respectively, indicating that the two deposits are formed almost at the same time, and the metallogenic epoch of the tow deposits are close to those of the hosting rocks formed by volcanic activity of Sawuer gold belt. This geochronological study supplies new evidence for determining the timing of gold mineralization, the geneses of gold deposits? and identifies that in Hercynian period, the Altai developed tectonic-magmatic-hydrothermal mineralization of Early Carboniferous period, except known two metallogenic mineralization periods including tectonic-magmatic-hydrothermal mineralization of Devonian period and Late Carboniferous-Permian period respectively. The study of fluid inclusions indicates that the ore-forming fluid is a type of NaCl-HbO fluid with medium-low temperature and low salinity, Au is transported by the type of auric-sulfur complex (Au (HS)2-), the ore is formed in reduction condition. Hydrogen and oxygen isotopes of fluid inclusions in the major mineralizating stage show that the solutions mainly originated from magmatic water and meteoric water. The fluid mixing and water-rock reaction cause the deposition of Au. The helium and argon isotope compositions of fluid inclusions hosted in pyrite have been measured from Kuoerzhenkuola and Buerkesidai gold deposits in Sawuer gold belt. The results show that the ore-forming fluids of two deposits possessed the same source and is a mixture of mantle- and partial meteoric water-derived fluid, and the reliability of He and Ar isotopic compositions in Hercynian period is discussed. Isotopic studies including H, O, He, C, S, Pb and Sr reveal the same result that the ore-forming fluids of two deposits possessed the same source: the water derived mainly from magmatic water, partially from meteoric water; the mineralizers and ore materials derived mainly from mantle beneath the island arc, and partially from crust. The ore-forming fluids of two deposits are a mixture of mantle-derived fluids being incorporated by crust-derived fluid, and shallow partial meteoric water. Based on these results, it is proposed that the geneses of the two gold deposits are the same, being volcanogenic late-stage hydrothermal gold deposits that the ore-forming fluids filled in fractures of volcanic apparatus and metasomatized the host rocks in the volcanic apparatus. It is the first time we carried out the geophysical exploration, that is, the EH-4 continuous electrical conductivity image system measurement, the results show that relative large-size mineralizing anomalies in underground have been discovered.lt can confirm the law and genesis of the deposits mentioned above, and change the two abandoned mines to current large-size potenial exploration target.

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利用多顶砧压机,以青藏高原北喜马拉雅构造带的天然斜长角闪岩为样品,在2.0GPa,800~1000℃条件下进行了两个系列的块状样品脱水部分熔融实验:(1)保持压力p=2.0GPa,加热时间t=12h不变,改变温度(800℃~1000℃)的实验;(2)保持压力p=2.0GPa,温度T=850℃不变,改变加热时间(12~200h)的实验.结果表明,2.0GPa,加热12h的条件下,随温度升高,斜长角闪岩中依次生成了石榴石、熔体和单斜辉石,熔体的成分呈英云闪长质-花岗闪长质-英云闪长质的演化趋势.2.0GPa,850℃条件下,随加热时间增加,斜长角闪岩中依次生成了石榴石、熔体和单斜辉石,熔体的成分由英云闪长质向花岗闪长质演化.当块状岩石样品中熔体体积百分比的含量达到5%时,熔体已经相互连通.温度大于850℃的条件下生成的熔体其粘度在104Pas量级,已经满足了在地质时间尺度上熔体分凝形成岩浆的粘度要求.因此,可以认为在增厚地壳的下部,斜长角闪岩的脱水部分熔融可以形成英云闪长质-花岗质岩浆.

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以贵州省贵阳市8 046 km2 为研究区域, 将土壤中镍的空间分布规律与环境地球化学机理研究相结合, 建立镍的区域土壤环境地球化学基线, 并进行污染分析. 通过对332 个样品的分析, 得到以下结论: 贵阳市表层土壤中镍的基线值为1710 mg/ kg , 大于5710 mg/ kg 的样品可能遭受人为污染. 地质累积指数分析结果显示贵阳市1912 %的表层土壤未受镍的污染, 6317 %的表层土壤在无污染到中度污染之间, 1618 % 的中度污染, 只有013 %的表层土壤介于中度污染到强污染之间. 污染程度指数分析则显示贵阳市64 %的表层土壤未受到镍的污染, 镍的污染程度最大为1156 , 总污染程度小于0 , 即总体未受到污染.

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目的:调查贵州省燃煤型氟中毒地区的氟源。方法:测定3个典型氟中毒重病村的煤、拌煤粘土、煤饼、煤饼灰的含氟量;调查贵州省煤含氟量。结果:化落、马家庄、偏坡寨3个村子的煤氟分别为107.8、104.1、117.6mg/kg,拌煤粘土氟分别为6103.7、1900.5、2619.7mg/kg,煤饼氟分别为805.3、480.7、1713.6mg/kg,煤饼灰氟分别为639.6、332.5、841.7mg/kg;贵州省煤氟均值为115.5mg/kg.结论:氟源主要是拌煤粘土,其含氟量一般很高。