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11.
The chemiluminescence (CL) of bis(2,4,6‐trichlorophyenyl) oxalate with hydrogen peroxide in the present of cationic surfactant and gold nanoparticles was studied. The CL emission was obviously enhanced in the presence of surfactant at a suitable concentration, with a synergetic catalysis effect exhibited. Different sizes of gold nanoparticles (15 and 50 nm) showed different effects on CL intensity. Mechanisms of the CL reaction and sensitization effect are discussed. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
12.
The nucleus of a blastula cell from Tilapia (Oreochromis nilotica, family Cichlidae, order Perciformes) was transplanted into an enucleated egg of Loach (Paramisgurnus dabryanus, family Cobitidae, order Cypriniformes). From among 3747 nucleo-cytoplasmic hybrid (NCH) eggs two NCH larval fish (0.05%) were obtained; one died on the 6th day and the other died on the 12th day after the operation. Morphological examinations showed that both NCH larval fish had developed normally with an opened mouth except they could not take food after complete utilization of their egg yolk on the 5th day of development. The possible mechanisms for obtaining such inter-order NCH larval fish are discussed. This is the first report indicating that inter-order NCH larval fish can be obtained in spite of their evolutionary divergence.  相似文献   
13.
本文进一步研究了我国不同民族的正常个体以及β地中海贫血患者θ珠蛋白基因5′侧序列中的多态性HincⅡ位点及其遗传性质。在广西壮族正常个体和β地中海贫血纯合子中,该多态性位点的发生频率均为75%,与正常汉族人测得值相近。家系分析资料表明,该多态性位点完全按照孟德尔规律进行遗传。  相似文献   
14.
D Schubert  L W Jin  T Saitoh  G Cole 《Neuron》1989,3(6):689-694
The regulation and function of two forms of the amyloid beta protein precursor (ABPP) that are released into the growth-conditioned medium of the PC12 nerve cell line were examined. Nerve growth factor increases the release of the form of ABPP without the protease-inhibitor domain relative to the protein containing the protease inhibitor and increases the overall rate of ABPP secretion 2-fold. In contrast, fibroblast growth factor increases the rate of ABPP secretion approximately 7-fold. Both forms of the secreted ABPP molecule are, in turn, able to stimulate adhesion of PC12 cells to substrata to which they are adsorbed about 10-fold more efficiently on a molar basis than Iaminin.  相似文献   
15.
植物群落演替与土壤发展之间的关系   总被引:46,自引:0,他引:46  
本文运用植物群落中植物优势种的重要值与相对应子群落的土壤特征值直接相关联的分析方法,对湖北宜昌大老岭的桦(Betula)、栎(Quercus)、栗(Castanea)七个群落类型的三个演替途径的土壤动态进行分析,结果表明:在植物群落的演替过程中,土壤中的Ca、pH值减少;离子代换量增加;Na、Mg、NH_4+-N、速效P、速效K、有机质的含量是随着物种的变化而呈不同的趋势。因此,植物群落的演替是生态系统的动态过程。  相似文献   
16.
Summary The cellobiose oxidizing enzyme of the newly isolated cellulolytic bacterium Cytophaga sp. LX-7 was produced extracellularly when grown on cellulose or other saccharides, which was previously noted only in fungi. The enzyme could use not only cellobiose, maltose, glucose and other saccharides but also cellulose as substrates, and use dichlorophenol indophenol and oxygen as electron acceptors.  相似文献   
17.
Stimulatory GTP-binding Protein (Gs) and adenylate cyclase prepared from bovine brain cortices were co-reconstituted into asolectin vesicles with or without 1000-fold transmembrane Ca2+ gradient. The results showed that both basal activity and Gs-stimulated activity of adenylate cyclase were highest in proteoliposomes with a transmembrane Ca2+ gradient similar to physiological condition (1 M Ca2+ outside and 1 mM Ca2+ inside) and lowest when the transmembrane Ca2+ gradient was in the inverse direction. Such a difference could be diminished following dissipation of the transmembrane Ca2+ gradient by A23187. Comparable conformational changes of Gs in proteoliposomes were also observed when Gs was labeled with the fluorescence probe, acrylodan. These results may indicate that a proper transmembrane Ca2+ gradient is essential not only for higher adenylate cyclase activity but also for its stimulation by Gs.  相似文献   
18.
生态环境对川芎产、质量的影响   总被引:3,自引:0,他引:3  
生态环境对川芎产、质量的影响丁德蓉,陈兴福,卢进,黄文秀,刘岁荣(四川省中医药研究院药物种植研究所,南川648408)InfluenceofEcoenvironmentontheYieldandQualityofLigusticumchuanxion...  相似文献   
19.
黑龙江省北五味子一新变种   总被引:2,自引:0,他引:2  
本文发表了黑龙江省产北五味子一新变种:白果五味子  相似文献   
20.
王海林  金冬雁 《病毒学报》1994,10(4):311-315
  相似文献   
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