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101.
细胞凋亡中线粒体的作用 总被引:2,自引:0,他引:2
细胞凋亡的研究在90年代以后成为生物研究领域的热点.最近研究证明线粒体是细胞凋亡的调控者,在细胞凋亡中起重要作用.本文主要介绍线粒体在凋亡中的分子学基础研究的最新进展. 相似文献
102.
Ming Li Yuanguang Li Helin Sheng H. Tamate R. Masuda J. Nagata N. Ohtaishi 《科学通报(英文版)》1999,44(8):719-719
Since the musk deer distributed in the Dabie Mountains, Anhui was defined asMoschus moschiferus anhuiensis, its status has been disputed based on researches of morphology and ecology. This study further probed into its taxonomic
status with principal components analysis (PCA) on skull measurements and mtDNA cytochrome b sequences (367 bp) analysis so
as to clear its status. It is concluded that the figure and skull in Anhui musk deer are different from other species, and
DNA divergence between it and other species is 6.24%–7.90%, which belongs to inter-specific difference. Thus, the study defines
this musk deer as one distinct species,Moschus anhuiensis (Wang, Huet al.) 相似文献
103.
用AOT/异辛烷反胶团系统萃取了添加不同浓度镁离子的猪心提取液中的细胞包素C.其结果为:添加0.025mol/LMg2+的萃取率E.R,(ExtractRatio)为96.5%(氧化型和还原型平均值).添加0.3mol/LMg2+的萃取率为28.3%。萃取后水相的吸收光谱中,还原型细胞色素C在520nm、550nm的吸收峰值消失。120nm的吸收峰值显著降低。萃取有机相的吸收光谱中,还原型细胞包素C在420nm、520nm和550nm处的特征吸收峰值显著。经反萃取后水相的吸收光谱与提取液以及萃取有机相的吸收光谱相同。说明添WMg2+后,经AOT/异辛烷萃取和反萃取过程能将细胞包素C从猪心提取液中萃取分离出来。 相似文献
104.
细胞色素P450酶系的异源表达研究 总被引:1,自引:0,他引:1
传统的药物代谢主要以实验动物为对象进行药物早期及临床研究,近几年来,结合生物化学与分子生物学的发展,药物早期代谢研究进入到药物体外代谢的研究阶段,主要围绕人肝内参与代谢的细胞色素P450家族展开.本文就近年来对此家族酶的异源表达及其在药物代谢中的应用进行了综述. 相似文献
105.
《Journal of Natural History》2012,46(9-10):521-552
Species of the genus Amphilius are small benthic catfishes that occur throughout tropical Africa and are abundant in the mountain streams of the Fouta Djalon region in Guinea, West Africa. During a 2003 expedition to the area, numerous amphiliid catfish were collected and initial observations revealed a large amount of morphological variation across the sampled basins. These specimens were subjected to a geometric morphometric analysis and standard morphometric analysis. Cytochrome b gene sequences were also obtained and compared among populations. These analyses resulted in the discovery of multiple cryptic taxa within two recognized species, Amphilius platychir and Amphilius rheophilus. The discovery of these taxa is compared with other recent discoveries from the area. 相似文献
106.
《Journal of Natural History》2012,46(47-48):2851-2872
In this study, the first molecular phylogenetic analysis of Mesobuthus eupeus in Iran is presented based on sequence data of a ~ 700-base-pair fragment of cytochrome C oxidase, subunit I. Phylogenetic relationships were inferred using parsimony, maximum likelihood and Bayesian inference. The results support monophyly of M. eupeus, but there is a clear divergence between northern and southern clades. The northern clade includes four subspecies – M. e. eupeus, M. e. philippovitschi, M. e. afghanus and M. e. thersites; whereas the southern clade is comprised of two others – M. e. phillipsi and M. e. kirmanensis. Accordingly, possible scenarios for the evolution and phylogeographic structure of M. eupeus based on the geological history of the Iranian Plateau were proposed. The observation of two distinct lineages supports the proposal that M. eupeus might be a species complex composed of species with highly similar morphological features. 相似文献
107.
Maiko Noda Alexei V. Abramov Galina Baranova Gennady Baryshinikov Hideo Ichikawa 《Journal of Natural History》2016,50(11-12):771-786
To test postglacial population expansion in small arboreal mammals dependent on boreal and subboreal forests, we used complete mitochondrial cytochrome b gene sequences (1140 bases) to investigate the phylogeography of the Eurasian red squirrel (Sciurus vulgaris orientis) on the Hokkaido Island of Japan. This subspecies is common in the boreal and subboreal forests of Hokkaido. We examined 61 specimens from 27 localities in Hokkaido. Phylogenetic relationships among 29 haplotypes found in the Hokkaido populations were not associated with geographic distribution of sampling localities. There were four mitochondrial DNA phylogroups. Phylogeographic analyses support sudden expansion of S. vulgaris orientis from restricted refugium in the southern part of Hokkaido during the last glacial period. The phylogeographic structure of this subspecies directly reflects the boreal and subboreal forest dynamics occurring in Hokkaido. 相似文献
108.
109.
分别将编码牛肝微粒体细胞色素b5水溶性结构域片段A1a7-Arg88和Ser5-Ser97基因在大肠杆菌JM83中高效表达,分离纯化后得到Tb5和Lb52种重组野生型蛋白。用核磁共振、紫外可见光谱、圆二色散光谱、循环伏安等方法研究结果表明,Lb5肽链2端残基未能使蛋白质的血红素周围环境与Tb5蛋白质N末端的Ser5和Lys62个残基所贡献。 相似文献
110.
Mantle pieces ofHyriopisis cumingii was treated by three kinds of solution, These mantle pieces were inserted together with paraffin nucleuses into the connective
tissue of three groups ofHyriopisis cumingii. These operated animals were cultured in a pool for a month. Several pearl sacs were put out and immersed by Bouin's solution
after every five days. Sections of each animals were made by histological method. Those without treatment were in a control
group. Observations of these sections showed that cytochrome c and yolk lecithin have an accelerated roles on pearl sac development
and pearl layer secretion. No effects on pearl sac development by polyvinyplyrrolidone (PVP).
Zheng Junying:born in May, 1966, Lecturer 相似文献