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41.
芪参补气药茶清除线粒体活性氧研究   总被引:2,自引:0,他引:2  
以黄芪和党参为原料,根据中医学原理组方制成芪参补气药茶(ACT),探索ACT清除线粒体活性氧作用及促进健康的机制。分别用AlCl3比色法和硫酸苯酚法测定ACT的功能因子总黄酮、总糖及总多糖含量。以还原型辅酶Ⅰ/吩嗪硫酸甲酯(NADH/PMS)为超氧阴离子(O2·)生成系统,过氧化氢(H2O2)/Fe2+体系为羟自由基(·OH)生成系统,分别用氮蓝四唑(NBT)还原法和Fenton反应显色法测定ACT清除O2·及·OH的能力;用Na2S2O3滴定法测定ACT清除H2O2的能力。ACT总糖质量分数为(26±1.3) mg·mL-1,总多糖质量分数为(12.5±0.8) mg·mL-1,总黄酮质量分数为(121±8.5) μg·mL-1。ACT可一定程度上清除O2·、·OH和H2O2。ACT具有温和的抗氧化作用,从而维持机体氧化与抗氧化平衡,这是ACT促进健康的潜在机制。  相似文献   
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Helminths, including flatworms and roundworms, are abundant organisms that have a variety of life histories. Of these, the genera Schistosoma, Echinococcus, Trichinella are notable parasites of veterinary and medical importance, and cause substantial socio- economic losses throughout China and the rest of the world. Genetic markers in the mitochondrial (mt) genome have proven use- ful for systematic, ecological, evolutionary and population studies, and the growth of mt genomic research has increased in the last two decades. Technological improvements, such as the long-polymerase chain reaction method and high-throughput se- quencing have allowed minute amounts of DNA from single worms, biopsy samples or microscopic organisms to be used for whole mt genome characterization. To facilitate the retrieval, annotation and analyses of mitochondrial features, multiple data- bases and specific software have also been designed and established. This review focuses on current progress, applications and perspectives regarding helminth mt genomics. To date, the complete mt genomes for 93 species of helminths have been sequenced and analyzed. Analyses of the mt genes, including gene content, arrangement, composition and variation have revealed unique features among the helminths when compared with other metazoans. This provides important data concerning their functional and comparative mitochondrial genomics, molecular taxonomy and characterization, population genetics and systematics, and evolu- tionary history. Moreover, mt genome data for parasitic helminths are important for diagnosis, epidemiology and ecology of in- fections. Mitochondrial genome data offer a rich source of markers for the systematics and population genetics of socioeconomi- cally important parasitic helminths of humans and other animals.  相似文献   
44.
《Journal of Natural History》2012,46(22):2863-2882
Morphological, molecular-genetic and breeding data were collected to investigate the species status of the Asian palm weevils, Rhynchophorus ferrugineus (Olivier) and R. vulneratus (Panzer) (Coleoptera: Curculionidae). These weevils are distinguished by characteristic colouring of the pronota and elytra, but naturally occurring colour intermorphs were observed. Contrary to the literature, quantitative measurements of the concavity of subgenal sutures and of pronotal shape indicated no differences between the two species. Larvae did not differ significantly in labral characteristics. Random amplified polymorphic DNA (RAPD) banding patterns were identical for nine of 14 primers, indicating that these weevils are very closely related. Sequences of the cytochrome oxidase gene for 201 base pairs read were identical for R. ferrugineus and R. vulneratus, but the congener R. bilineatus differed from them by 10%, suggesting divergence of these lineages about 5?million years ago. Hybrid F1s were obtained from all heterospecific crosses, and one surviving hybrid F1 female produced viable eggs. Previous studies have revealed no pheromonal differences. On the basis of this evidence, R. ferrugineus and R. vulneratus should be considered colour morphs of the same species and be synonymized under the name Rhynchophorus ferrugineus (Olivier), with the common name Asian palm weevil.  相似文献   
45.
The Neotropical genus Leptodactylus is currently represented by three species in the West Indies (Leptodactylus albilabris, Leptodactylus fallax and Leptodactylus validus). Based on morphological, acoustic and molecular evidence, we document the presence of a fourth species in the Caribbean region, Leptodactylus fragilis (Brocchi, 1877). The species was found at two localities in western Cuba, and molecular data suggest a northern South American origin, possibly Venezuela, for these populations. We discuss the potential invasive status of L. fragilis, based on its known distribution, relative abundance, behaviour and possible impacts on native species of Cuban amphibians.  相似文献   
46.
ABSTRACT

We examined genetic relationships among individuals and populations of the species Holbrookia lacerata, the spot-tailed earless lizard, using whole mitochondrial genomes. Lizards were collected from south, central and west Texas. We found significant amounts of genetic structure among populations and evidence of two major reciprocally monophyletic groups of spot-tailed earless lizards in Texas. Holbrookia lacerata lacerata occurs on the Edwards Plateau and adjacent regions of West Texas north of the Balcones Escarpment, while Holbrookia lacerata subcaudalis occurs in South Texas and adjacent Mexico south of the Balcones Escarpment. These two recognised subspecies correspond to the two clades we discovered. Holbrookia l. lacerata occupies much of its historical range at sometimes high population densities, while populations of H. l. subcaudalis appear to be highly fragmented based on recent observations compared to their historical range.  相似文献   
47.
烟草锰超氧化物歧化酶(MnSOD)是一种由核基因编码并定位于线粒体的蛋白质,是植物体内清除超氧根阴离子的主要酶类.采用RT—PCR方法,从烟草(Nicotiana tubaccum)中克隆到MnSODeDNA基因(SodA),序列分析结果与文献报告的资料相比,核苷酸序列的同源性为99.9%,氨基酸序列的同源性为99.6%.该基因能在原核表达载体pBV221中正确表达,并表现出SOD酶活性.  相似文献   
48.
Approximately 60% of subjects with schizophrenia present minor neurological signs (neurological soft signs, NSS), which include abnormalities in sensory and motor performance indicative of a non-specific cerebral dysfunction. These are also present in healthy individuals and relatives of patients with psychosis, at significantly lower rates. The excess of NSS in psychosis may be a potential endophenotype for this disorder, and reflect the same neurodevelopmental brain dysfunction that also underlies the cog...  相似文献   
49.
利用Illumina和Pacbio测序技术对扬子鳃蛭(Ozobranchus jantseanus)线粒体基因组全序列进行测序及注释,并与NCBI数据库中蛭纲(Hirudinea)其他物种的线粒体全序列的排列方式和系统进化关系进行了比较,以确定其系统学地位.结果显示:获得的线粒体基因组序列长度为14 868 bp,蛋白编码基因存在2种起始密码子,分别为ATG和ATT;终止密码子共有4种,分别为TAA,TAG,TA和T;蛭纲10个物种的线粒体基因组全序列基因排序可分为2种类型,其差异表现在tRNAs的互换和长非编码区的长度的不同;扬子鳃蛭所属的吻蛭目(Rhynchobdellida)均为b型,绝大部分无吻蛭目(Arhynchobdellida)的排列方式为a型.基于蛭纲物种的13个蛋白编码基因(PCGs)的Neighbor-Joining(NJ)树进化分析显示,扬子鳃蛭与其他吻蛭目物种聚类.  相似文献   
50.
《Journal of Natural History》2012,46(19-20):1219-1227
The complete mitochondrial genome sequence of the forest musk deer (Moschus berezovskii) was determined. Sequence analysis revealed that the organization of the mitochondrial genome in the forest musk deer was consistent with that of other reported mammals. Molecular phylogenetic analysis of the forest musk deer and 22 other species of the order Cetartiodactyla was conducted using maximum parsimony and Bayesian inference methods based on the 12 heavy‐strand protein‐coding genes, RNA genes and their combination. Both the consensus phylogenetic trees and the topologies test supported the monophyly of Cervidae, Bovidae and Cetancodonta, and placed Moschidae as a sister group to Cervidae/Bovidae.  相似文献   
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