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81.
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   
82.
The present work reports the isolation and characterization of new polymorphic microsatellites in mung bean (Vigna radiata L.). Of 93 designed primer pairs, seven were found to amplify polymorphic microsatellite loci, which were then characterized using 34 mung bean accessions. The number of alleles ranged from two to five alleles per locus with an average of three alleles. Observed and expected heterozygosity values ranged from 0 to 0.088 and from 0.275 to 0.683, respectively. All seven loci showed significant deviations from Hardy–Weinberg equilibrium, whereas only one pairwise combination (GBssr‐MB77 and GBssr‐MB91) exhibited significant departure from linkage disequilibrium. These newly developed markers are currently being utilized for diversity assessment within the mung bean germplasm collection of the Korean Gene Bank.  相似文献   
83.
纤维素在不同介质中的吸附碱的研究   总被引:1,自引:0,他引:1  
文中研究了纤维素在不同介质(水、乙醇、吡啶及N,N-二甲基乙酰胺)中吸附碱测定情况并通过对比总结出了纤维素对氢氧化钠随用碱量及介质变化规律:纤维素的吸附碱量随着介质及用碱量不同而有所变化,用水作碱化介质比用有机溶剂/水作碱化介质时的吸附碱量少;在用有机溶剂/水作碱化介质时,纤维素对碱吸附表现出大致相同的变化趋势。  相似文献   
84.
85.
Sticholysin II (St II) is a haemolytic toxin isolated from the sea anemone Stichodactyla helianthus. The high haemolytic activity of this toxin is strongly dependent on the red cell status and the macromolecule conformation. In the present communication we evaluate the effect of human serum albumin on St II haemolytic activity and its capacity to form pores in the bilayer of synthetic liposomes. St II retains its pore forming capacity in the presence of large concentrations (up to 500 μM) of human serum albumin. This effect is observed both in its capacity to produce red blood cells haemolysis and to generate functional pores in liposomes. In particular, the capacity of the toxin to lyse red blood cells increases in the presence of human serum albumin (HSA). Regarding the rate of the pore forming process, it is moderately decreased in liposomes and in red blood cells, in spite of an almost total coverage of the interface by albumin. All the data obtained in red cells and model membranes show that St II remains lytically active even in the presence of high HSA concentrations. This stubbornness can explain why the toxin is able to exert its haemolytic activity on membranes immersed in complex plasma matrixes such as those present in living organisms.  相似文献   
86.
87.
Kinetic analysis of vitamin C uptake has demonstrated that specialized cells take up ascorbic acid (AA), the reduced form of vitamin C, through sodium‐AA cotransporters. Recently, two different isoforms of sodium‐vitamin C cotransporters (SVCT 1, 2) that mediate high affinity Na+‐dependent l ‐ascorbic acid have been cloned. SVCT2 was detected mainly in choroid plexus cells and neurons, however, there are no evidences of SVCT2 expression in glial cells. High concentrations of vitamin C has been demonstrated in brain hypothalamic area. The hypothalamic glial cells, known as alpha and beta tanycytes, are specialized ependymal cells that bridge the cerebrospinal fluid and the portal blood of the median eminence. Our hypothesis postulates that tanycytes take up reduced vitamin C from the portal blood and cerebrospinal fluid generating an high concentration of this vitamin in brain hypothalamic area. In situ immunohistochemical analyses demonstrated that SVCT2 transporter is selectively expressed in apical region of tanycytes. A newly developed primary culture of mouse hypothalamic tanycytes was used to confirm the expression and function of SVCT2 isoform in these cells. Reduced vitamin C uptake was temperature and sodium dependent. Kinetic analysis showed an apparent Km of 20 μm and a Vmax of 45 pmol/min per million cells for the transport of ascorbic acid. The expression of SVCT2 was confirmed by immunoblots and RT–PCR. Tanycytes may perform a neuroprotective role concentrating the vitamin C in the hypothalamic area. Acknowledgements: Supported by Grands FONDECYT 1010843 and DIUC‐GIA 201.034.006‐1.4 from Concepción University.  相似文献   
88.
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   
89.
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   
90.
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   
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