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121.
A new Ru(II) complex, [Ru(bpy)(2)(dhipH3)](ClO4)(2) (in which bpy=2,2'-bipyridine, dhipH(3)=3,4-dihydroxy-imidado[4,5-f][1,10]-phenanthroline), was synthesized and characterized, and the pH effect on the emission spectra of the complex was studied. The interaction of the complex with calf thymus DNA was investigated by UV-visible and emission spectroscopy, and viscosity measurements. The results suggest that the complex acted as a sensitive luminescent pH sensor and a strong ct-DNA intercalator with an intrinsic binding constant of (4.0+/-0.7) x 10(5) M(-1) in buffered 50 mM NaCl. 相似文献
122.
Meng Xiao Qun Li Liang Guo Tong Luo Wen-Xia Duan Wen-Xing He Li Wang Fang Chen 《Biochemical genetics》2006,44(1-2):44-57
Amplified fragment length polymorphism (AFLP) markers were used to estimate the genetic diversity of seven wild populations of Sinopodophyllum hexandrum (Royle) Ying from the Tibetan region of Sichuan Province, China. Six primer combinations generated a total of 428 discernible DNA fragments, of which 111 were polymorphic. The percentage of polymorphic bands (PPB) was 25.93 at the species level, and PPB within population ranged from 4.91 to 12.38%. Genetic diversity (H
E) within populations varied from 0.01 to 0.04, averaging 0.05 at the species level. As revealed by the results of AMOVA analysis, 58.8% of the genetic differentiation occurred between populations, and 41.2% within populations. The genetic differentiation was, perhaps, due to the limited gene flow (N
m=0.43) of the species. The correlation coefficient (r) between genetic and geographical distance using Mantel's test for all populations was 0.698 (P=0.014). The UPGMA cluster analysis revealed a similar result in that the genetic distances among the populations show, to a certain extent, a spatial pattern corresponding to their geographic locations. On the basis of the genetic and ecological information, we propose some appropriate strategies for conserving the endangered S. hexandrum in this region. 相似文献
123.
Amplified fragment length polymorphism (AFLP) markers were used to estimate the genetic diversity of seven wild populations of Sinopodophyllum hexandrum (Royle) Ying from the Tibetan region of Sichuan Province, China. Six primer combinations generated a total of 428 discernible DNA fragments, of which 111 were polymorphic. The percentage of polymorphic bands (PPB) was 25.93 at the species level, and PPB within population ranged from 4.91 to 12.38%. Genetic diversity (H(E)) within populations varied from 0.01 to 0.04, averaging 0.05 at the species level. As revealed by the results of AMOVA analysis, 58.8% of the genetic differentiation occurred between populations, and 41.2% within populations. The genetic differentiation was, perhaps, due to the limited gene flow (Nm = 0.43) of the species. The correlation coefficient (r) between genetic and geographical distance using Mantel's test for all populations was 0.698 (P = 0.014). The UPGMA cluster analysis revealed a similar result in that the genetic distances among the populations show, to a certain extent, a spatial pattern corresponding to their geographic locations. On the basis of the genetic and ecological information, we propose some appropriate strategies for conserving the endangered S. hexandrum in this region. 相似文献
124.
川芎嗪对脑缺血/再灌注后所致肺损伤的影响 总被引:2,自引:0,他引:2
目的:观察川芎嗪对脑缺血/再灌注后肺损伤的影响。方法:采用Pulsinelli等的方法建立大鼠急性全脑缺血/再灌注模型。将Wistar大鼠随机分为三组,即:对照组(Control)、缺血/再灌注组(I/R)、川芎嗪+缺血/再灌注组(TEP+I/R),分别测定各组肺功能(PaO2、PaCO2),肺系数(LI%)、血浆和肺组织中与自由基有关物质的含量。结果:川芎嗪可有效改善脑缺血/再灌注后肺功能,减轻肺水肿,减少胞浆酶的漏出,增加自由基清除醇的活性,抑制组织脂质过氧化的发生。结论:川芎嗪对脑缺血/再灌注后肺损伤具有保护作用,其机制可能与其抗氧自由基和膜保护作用有关。 相似文献
125.
126.
A monolithic enzymatic microreactor was prepared in a fused-silica capillary by in situ polymerization of acrylamide, glycidyl methacrylate (GMA) and ethylene dimethacrylate (EDMA) in the presence of a binary porogenic mixture of dodecanol and cyclohexanol, followed by ammonia solution treatment, glutaraldehyde activation and trypsin modification. The choice of acrylamide as co-monomer was found useful to improve the efficiency of trypsin modification, thus, to increase the enzyme activity. The optimized microreactor offered very low back pressure, enabling the fast digestion of proteins flowing through the reactor. The performance of the monolithic microreactor was demonstrated with the digestion of cytochrome c at high flow rate. The digests were then characterized by CE and HPLC-MS/MS with the sequence coverage of 57.7%. The digestion efficiency was found over 230 times as high as that of the conventional method. In addition, for the first time, protein digestion carried out in a mixture of water and ACN was compared with the conventional aqueous reaction using MS/MS detection, and the former solution was found more compatible and more efficient for protein digestion. 相似文献
127.
Xin-Hong Duan Jin-Ping Qiao Yang Yang Meng-Chao Cui Jiang-Ning Zhou Bo-Li Liu 《Bioorganic & medicinal chemistry》2010,18(3):1337-1343
A group of novel 4,5-dianilinophthalimide derivatives has been synthesized in this study for potential use as β-amyloid (Aβ) plaque probes. Staining of hippocampus tissue sections from Alzheimer’s disease (AD) brain with the representative compound 9 indicated selective labeling of it to Aβ plaques. The binding affinity of radioiodinated [125I]9 for AD brain homogenates was 0.21 nM (Kd), and of other derivatives ranged from 0.9 to 19.7 nM, except for N-methyl-4,5-dianilinophthalimide (Ki > 1000 nM). [125I]9 possessed the optimal lipophilicity with Log P value of 2.16, and its in vivo biodistribution in normal mice exhibited excellent initial brain uptake (5.16% ID/g at 2 min after injection) and a fast washout rate (0.56% ID/g at 60 min). The encouraging results suggest that this novel derivative of [123I]9 may have potential as an in vivo SPECT probe for detecting amyloid plaques in the brain. 相似文献
128.
子宫颈糜烂病毒病因的探讨 总被引:17,自引:0,他引:17
491份宫颈拭子病毒分离结果表明:糜烂宫颈单纯疱疹病毒(HSV)分离阳性率(30.8%)是正常宫颈(2.6%)的11.8倍,用人干扰素治疗一个疗程后,病毒分离率下降至疗前的1/4.36例糜烂宫颈活体组织DNA分子杂交表明,乳头瘤病毒16型(HPV-16)阳性者占52.8和,HPV-18占17.9%,HPV-6B占28.1%,HPV-11占7.7%,251例宫颈糜烂患者经人(?)D型基因工程干扰素双盲对比治疗后,总有效率达93.8%,显效率达60%,分析临床疗效与HSV分离率的变化表明,临床有效病例中有35%(49/140)在治疗后病毒阴转,有57%在疗前疗后均未分离出HSV,有5%在疗前疗后保持阳性不变,有2.9%疗前阴性,疗后阳性,上述结果表明,HSV和HPV与慢性宫颈炎有一定关系。 相似文献
129.
Helicobacter pylori (H. pylori) plays an essential role in the development of various gastroduodenal diseases; however, no vaccines preventing H. pylori infection have been available now. This study was to evaluate the protective effect of rOmp22–HpaA fusion protein against H. pylori infection in mouse model and to screen the candidate to be used in the development of an oral vaccine against H. pylori. rOmp22, rHpaA, rOmp22+rHpaA, and rOmp22–HpaA groups were used to immunize mice with mLT63 as adjuvant by intragastric route, respectively, four times at 1-week intervals. Two weeks after last immunization, all of the animals were orally challenged with H. pylori NCTC11637 and then were killed after another 2 weeks. The mice gastric tissue of all groups was separated to detect the presence of infection by urease tests, to culture H. pylori, and to observe the histological characteristics. The protective effect against H. pylori challenge in mice immunized with rOmp22–HpaA fusion protein and mLT63 adjuvant was significantly higher than PBS and mLT63 control groups (P < 0.05), but no significant difference was detected among rOmp22, rHpaA, rOmp22+rHpaA, and rOmp22–HpaA groups (P > 0.05). rOmp22–HpaA fusion protein retained immunogenicity and could be used as an antigen candidate in the development of an oral vaccine against H. pylori infection. 相似文献
130.
槭属(Acer L.)属槭树科(Aceraceae),200种,分布于亚、欧、北美和非洲北缘。本文研究了槭属的系统演化、地理分布、起源与扩散。认为:(1)槭树科与无患于科关系密切,槭属是槭树科2属中较进化的类群。(2)在原始而典型的槭属植物的基础上,槭属沿花的各部减少,有的器官甚至向完全退化的方向演化,但也有少数向增加数目的方向特化。(3)讨论了槭属4亚属23组的演化趋势,并绘制出其系统演化图。(4)槭属起源于侏罗纪的中国四川东部、湖北、湖南及其邻近地区,并向西、东北和南方扩散而进入西亚、欧洲、非洲北缘、北美洲和马来半岛至印尼。 相似文献