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71.
构建重组质粒pcDNA4/HisA-LMO3,转染C8-D1A胶质细胞,对照组为pcDNA4/HisA空载体质粒转染组和未转染组,MTT观察各组细胞的体外生长情况,流式细胞术(FCM)测定各组细胞的细胞周期和凋亡细胞百分比,Western-blot检测LMO3转染后凋亡相关蛋白的表达变化,从而观察LMO3基因对C8-D1A胶质细胞体外生长的影响.RT-PCR、Western印迹显示pcDNA4/HisA-LMO3转染组LMO3mRNA及LMO3蛋白表达水平明显高于对照组;与对照组细胞相比,转染组细胞的增殖能力明显高于空载体对照组及C8细胞(P0.01),S期细胞增加,G0/G1期细胞减少,C8细胞转染LMO3后可以促进C8细胞从G0/G1期进入S期,从而促进细胞的增殖. 相似文献
72.
ABSTRACT This paper is intended as an investigation of the biogeographic characteristics of ant faunas of the eight islands in West Sea of South Korea, using quantitative genetic analyses. The faunal similarity is examined using the Nomura-Simpson's Coefficient (NSC). The obtained NSC value matrix was examined by a cluster analysis using UPGMA method. The MSC-values between the seven areas investigated range from 0.500 (Deokjeokdo Hongdo) to 0.909 (Wonsando-Hongdo). In these islands including Seonyudo, the NSC -values range from 0.571 (Deokjeokdo) to 0.778 (Bigeumdo). The cluster analysis using the similarity index (NSC) showed that eight islands were divided into two groups at the level of 41%. It was shown that Wonsando and Bigeumdo were closer (Similarity = 83%) than those between others. Deokjeokdo and Bigeumdo were remote (Similarity = 41%) from each conspecific population. That is, the species composition of Bigeumdo (Similarity = 70%) was similar to that of the Seonyudo, while that of Deokjeokdo (Similarity = 41%) was different from that. 相似文献
73.
T. T. T. HA M. OKABE K. MORISHIMA I. NAKAYAMA K. NAGASAWA T. UMINO 《Molecular ecology resources》2007,7(4):635-637
Multiplex polymerase chain reaction (PCR) technique has recently been applied to gain many advantages in molecular genetics. The present study focused on the development of 15 new microsatellite markers with multiplex PCR systems in ayu, Plecoglossus altivelis, an important freshwater fish in Japan. All loci were followed Mendelian inheritance in 27 F1 progeny except for the one locus. The number of alleles per locus ranged from nine to 44 and the observed heterozygosities ranged from 0.680 to 0.980 in 50 unrelated individuals. The results indicate that these new microsatellite markers are useful for studies of linkage mapping and population genetics for the species. 相似文献
74.
为明确大气CO_2浓度升高对宁夏枸杞光合特性及生物量分配的影响,以宁夏枸杞苗木为试材,采用开顶气室(OTC)模拟自然环境大气CO_2浓度变化,设置3个CO_2浓度水平[CK(380±20μmol/mol)、TR1(570±20μmol/mol)、TR2(760±20μmol/mol)],分别于不同CO_2浓度处理90d、120d后,测定其净光合速率(P_n)、光响应曲线、CO_2响应曲线等相关指标及植株不同器官生物量。结果表明:(1)TR1及TR2下Pn于第一年处理至90d时均较CK显著升高(P0.05),且TR1处理在120d时较CK显著降低;第二年处理90d时,TR1处理较CK下降了4.77%,处理120d时TR1、TR2均高于CK,但差异不显著。(2)随着CO_2浓度升高,两年中TR1、TR2处理的胞间CO_2浓度(C_i)较CK均显著升高,处理后120d时,气孔导度(G_s)较CK均显著下降;水分利用率(WUE)在第一年处理中均无显著变化,但在第二年处理120d时,TR1、TR2均较CK显著上升。(3)处理至90d和120d时,TR1、TR2组的宁夏枸杞苗木光饱和点、CO_2饱和点均高于CK,但TR2组初始羧化效率低于CK。(4)随着CO_2浓度升高,宁夏枸杞苗木地上部分生物量分配显著增加,地下部分生物量分配显著降低。研究发现,一定时间内适宜CO_2浓度升高可促进宁夏枸杞苗木光合作用,使得其地上部分生物量分配显著提高,地下部分生物量分配显著降低;但随着处理浓度升高及处理时间延长,其光合作用有下调趋势,表现为净光合速率、气孔导度、初始羧化效率等下降。 相似文献
75.
在内蒙古通辽市科尔沁左翼后旗蒙古族居住地区采用随机抽样和农户推荐选择30个农户,同时在邻近地区的汉族选择了10个农户作为对比分析。庭园样方取样为整个庭园面积,设立40个样方进行调查。结果表明,内蒙古通辽市科尔沁左翼后旗蒙古族庭园和邻近地区汉族庭园植物垂直结构主要有0~1 m、1~2 m、2~5 m、5~10 m、10 m等五类,其中不论是小规模庭园还是大规模庭园,5 m以下的阶层占优势;两个民族庭园植物种植模式研究结果阐明科尔沁左翼后旗蒙古族与邻近汉族相比,目前很少栽培观赏植物,仍停留在与日常生活相关的蔬菜植物栽培的水平上,而邻近的汉族已开始注重栽培美化环境的庭园植物。此外,本研究运用MVSP统计软件分析庭园类型表明科尔沁左翼后旗蒙古族庭园主要有4种类型,邻近的汉族庭园有3种类型,并且当地蒙古族与邻近的汉族庭园有所差异,这些差异是由两个民族间农耕文化传统以及畜牧业植物文化差异、庭园面积、庭园历史及庭园管理水平、传统植物利用知识的差异所造成。 相似文献
76.
In this paper we present a multi-strain model for hepatitis C virus (HCV) including an immune response term. The model is presented and discussed. Also we argue that the added multi-strain term represents some basic properties of the immune system and that it should be included to study longer term behavior of the disease. 相似文献
77.
ABSTRACT: BACKGROUND: Pockmarks (depressions in the seabed) have been discovered throughout the world's oceans and are often related to hydrocarbon seepage. Although high concentrations of pockmarks are present in the seabed overlaying the Troll oil and gas reservoir in the northern North Sea, geological surveys have not detected hydrocarbon seepage in this area at the present time. In this study we have used metagenomics to characterize the prokaryotic communities inhabiting the surface sediments in the Troll area in relation to geochemical parameters, particularly related to hydrocarbon presence. We also investigated the possibility of increased potential for methane oxidation related to the pockmarks. Five metagenomes from pockmarks and plain seabed sediments were sequenced by pyrosequencing (Roche/454) technology. In addition, two metagenomes from seabed sediments geologically unlikely to be influenced by hydrocarbon seepage (the Oslofjord) were included. The taxonomic distribution and metabolic potential of the metagenomes were analyzed by multivariate analysis and statistical comparisons to reveal variation within and between the two sampling areas. RESULTS: The main difference identified between the two sampling areas was an overabundance of predominantly autotrophic nitrifiers, especially Nitrosopumilus, and oligotrophic marine Gammaproteobacteria in the Troll metagenomes compared to the Oslofjord. Increased potential for degradation of hydrocarbons, especially aromatic hydrocarbons, was detected in two of the Troll samples: one pockmark sample and one from the plain seabed. Although presence of methanotrophic organisms was indicated in all samples, no overabundance in pockmark samples compared to the Oslofjord samples supports no, or only low level, methane seepage in the Troll pockmarks at the present time. CONCLUSIONS: Given the relatively low content of total organic carbon and great depths of hydrocarbon containing sediments in the Troll area, it is possible that at least part of the carbon source available for the predominantly autotrophic nitrifiers thriving in this area originates from sequential prokaryotic degradation and oxidation of hydrocarbons to CO2. By turning CO2 back into organic carbon this subcommunity could play an important environmental role in these dark oligotrophic sediments. The oxidation of ammonia to nitrite and nitrate in this process could further increase the supply of terminal electron acceptors for hydrocarbon degradation. 相似文献
78.
ANDRÉ A. PADIAL STEVEN A. J. DECLERCK LUC DE MEESTER CLÁUDIA C. BONECKER FABIO A. LANSAC‐TÔHA LUZIA C. RODRIGUES ALICE TAKEDA SUELI TRAIN LUIZ F. M. VELHO LUIS M. BINI 《Freshwater Biology》2012,57(11):2411-2423
1. Community concordance measures the level of association between the compositional patterns shown by two groups of organisms. If strong community concordance occurs, one group could be used as a surrogate for another in conservation planning and biodiversity monitoring. In this study, we evaluated the variability in the strength of community concordance, the likely mechanisms underlying community concordance and the degree to which one community can predict another in a set of Neotropical floodplain lakes (Upper Paraná River floodplain, Brazil). 2. We used a data set including six aquatic communities: fish, macrophytes, benthic macroinvertebrates, zooplankton, phytoplankton and periphyton. We used Mantel and PROTEST approaches to evaluate the levels of community concordance in up to four sampling periods. Also, we used partial Mantel test and information about biotic interactions to investigate reasons for observed patterns of concordance. Finally, we used co‐correspondence analysis to evaluate the performance of one taxonomic group in predicting the structures of other communities. 3. The levels of community concordance varied over time for almost all cross‐taxa comparisons. Concordance between phytoplankton and periphyton probably resulted from similar responses to environmental gradients, whereas other patterns of concordance were likely generated by interactions among groups. However, the levels of predictability were low, and no particular taxonomic group significantly predicted all other groups. 4. The low and temporally variable levels of community concordance cast doubts on the use of surrogate groups for biodiversity management in Neotropical floodplains. 相似文献
79.
目的比较氯胺酮、地西泮和丙泊酚复合麻醉在外科教学中对犬的麻醉效果。方法成年健康杂种犬42条,诱导麻醉相同,均肌注氯胺酮(10 mg/kg)和氟哌利多(0.5 mg/kg)混合液。静脉维持采用不用的方法,分为三组,分别是静脉滴注氯胺酮地西泮混合液(n=12)、静脉推注氯胺酮地西泮混合液(n=12)和静脉滴注丙泊酚利多卡因混合液(n=18)。结果三组麻醉效果显示,静脉滴注丙泊酚利多卡因混合液效果最好,优83.3%,良16.7%,死亡率0%。结论在外科教学中,对犬采用丙泊酚复合麻醉是一种较为理想的麻醉方法。 相似文献
80.