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1.
杨亲二 《中国科学院研究生院学报》2001,39(6):502-514
研究了12种乌头属Aconitum L．和18种翠雀属Delphinium L．植物的染色体。在12种乌头属植物中，除粗花乌头A．crassiflorum为四倍体(2n=4x=32)外，其他种类都为二倍体(2n=2x＝16)，中甸乌头 A.piepunense中有B染色体存在，牛扁亚属Aconitum subgen．Lycoctonum的二倍体植物与乌头亚属Aconitum subgen．Aconitum 植物的染色体在大小和形态上有明显区别；所有18种翠雀属植物都为二倍体(2n＝2x=16)，其染色体在大小和形态上极为相似，但与乌头亚属的染色体易于区别。翠雀属植物的核型不对称性程度明显高于乌头属植物，因此从染色体证据来看，翠雀属要比乌头属进化。 相似文献
2.
论中国-喜马拉雅植物亚区乌头属植物地理分布特点 总被引：1，自引：0，他引：1
李良千 《中国科学院研究生院学报》1988,26(3):189-204
本文对乌头属Aconitum L．植物分布区内各地区的分布作了分析，统计了各地区不
同等级分类群的频度，认为中国-喜马拉雅植物亚区是乌头属植物地理分布最大的频度中心、
多样性中心和特有种的分布中心。 文中还讨论了乌头属内的演化关系，以及本属与邻近属的
系统发育关系，发现在中国-喜马拉雅植物亚区既有许多原始类群，又有大量的进化类群，提出
了本亚区不但是本属植物原始类群的保存中心，而且是活跃的分化中心。产生上述结果的原因可能与喜马拉雅山脉的抬升以及本亚区复杂的自然条件有着密切的关系。 相似文献
3.
国产乌头属的化学分类 总被引：2，自引：0，他引：2
根据二萜生物碱的类型、生物合成、在乌头属植物中的分布，并参照国产乌头属的系统分类、形态演化和地理分布，本文讨论国产乌头属的化学分类。 1．以牛扁碱型成分为主的牛扁亚属和以乌头碱型成分为主的乌头亚属可能在乌头属进化的初期阶段就已分化，各自沿着独立的道路发展。2．乌头亚属包括以下类群：(1)以阿替生型、维特钦型、乌头碱型胺酵和 酯碱为主的保山乌头系，主要分布于国产乌头属近代发展分化中心之一的横断山脉和金沙江流域，可能国产乌头组的近代分化就是由该系发展而来; (2)以乌头碱、中乌头碱、下乌头碱为主的乌头系，为进化程度较高的群，所含乌头碱及尼奥灵显示了该系与保山乌头系的亲缘关系; (3)以乌头碱和松果灵为主的准噶尔乌头系，所含乌头碱和松果灵显示了该系与保山乌头系的亲缘关系; (4)以滇乌碱类酯碱为主的显柱乌头系和蔓乌头系，为进化程度较高的群，其酯碱有别于乌头碱类。3．以阿替生及C19内酯型为主的甘青乌头系及圆叶乌头系，可能为进化早期形成的高山特化类群。4. 以阿替生和C19乌头碱型胺醇为主的露蕊乌头亚属，可能为特化类群。 相似文献
4.
本文对中国乌头属Aconitum三亚属53种及变种的药用植物进行了比较解剖学的研究。纳出该属植物根部组织构造的6大类型和18种亚型，找出了鉴定乌头类药材的解剖学特征。并结合植物分类学。化学分类学、细胞染色体和毒性，探讨了该属组织构造与植物系统演化之间的相关性。结果表明根部具有较进化的I型和II型构造的植物，含毒性很大的双酯型生物碱，主要存在于乌头亚属乌头组3，5-11系中；较原始的Ⅲ型、Ⅳ型及少数小根类Ⅱ型构造的植物，含毒性较小的阿替生和胺醇类生物碱，主要存在于露蕊乌头亚属和乌头亚属乌头组1—2系；更原始的V型和Ⅵ型构造的植物，含毒性更小的牛扁碱型生物碱，主要存在于牛扁亚属中。本文还从解剖学的角度对乌头属下等级的系统位置作了讨沦。 相似文献
5.
发现卧龙乌头Aconitum wolongense W．T. Wang的模式实际上包含两种植物，即毛果甘青乌头A．
tanguticum (Maxim．)Stapf．var．trichocarpum Hand.-Mazz．和展毛大渡乌头A．franchetii Fin.et Gagnep．var．villosum W．T. Wang，故将该种予以归并。 相似文献
6.
7.
本文测定了广义榆科 Ulmaceae s．l．及其近缘类群的trn K基因5′端内含子区序列。在尝试利用该内含子区进行榆科系统发育研究的同时，探讨了其在植物系统学研究中的应用前景。利用PAUP软件进行的系统发育分析仅得到1棵最简约树。该简约树的树长为665步，其一致性指数(CI)和保持性指数(RI)分别为0.7714和0.7965。分析结果表明：广义榆科为多系群；狭义榆科Ulmaceae s．str．为荨麻目rticales其他类群的姊妹群；大麻科Cannabacea嵌在朴科Celtidacea中，即朴科为一并系群；系统位置有争议的2个属——白颜树属Gironniera和糙叶树属 Aphananthe与朴科类群聚为一支。本研究还表明trnK基因5′端内含子区序列分析在植物较低分类等级(如近缘属间，属下种间)的系统发育研究中具有很好的应用前景。 相似文献
8.
测定了红豆杉科、三尖杉科、罗汉松科及松科共9属13种植物的matK基因序列,发现3′端的单碱基插入造成mat k基因在这些类群间有较大的长度变异(1488∽1548bp),其它插入或缺失的长度为3、6或9bp(白豆杉中有一个长为27bp的缺失),且绝大多数插入或缺失事件具有系统发育信息。matK基因中,密码子第1、2及3位的变异率较为相近,平均同义替代率约为平均非同义替代率的2倍。以松科2属3种植物为外类群,运用PAUP软件进行的系统发育分析仅得到一棵最简约树(步长为895,CI=0．850,RI=0．876),该简约树的各分支均得到bootstrap分析的极强支持。结果表明：红豆杉科与三尖杉科均为单系群,二者互为姐妹群;白豆杉属与穗花杉属为红豆杉科中两个很自然的属,白豆杉属为红豆杉属的姐妹群,穗花杉属为榧树属的姐妹群。竹柏属与罗汉松属聚为一支,二者间的亲缘关系得到boot-strap分析的100％支持,从分支分类学及遗传距离角度,作者不赞同将竹柏属提升为科。 相似文献
9.
运用PCR方法分别从松科8属、9种植物中扩增出一长约2550bp的cpDNA片段，这一片段包括rbcL、trnR、部分accD及基因间的非编码区(相对于黑松cpDNA中的同源片段而言)。运用18种限制性内切酶对这一cpDNA片段进行酶切分析，共获得86个酶切位点，其中54个为变异位点。运用PAUP(version 3．1．1)和Mega(version 1．01)软件对数据进行分析，结果Wagner简约树和Neighbor-Joining树反映出的松科系统发育关系基本一致：银杉属、松属、黄杉属和落叶松属形成一个单系群，且银杉属与松属的亲缘关系更近于与另外二属的关系，但这一结果未得到Bootstrap分析的较强支持；落叶松属近缘于黄杉属；冷杉属近缘于油杉属。此外，松科中的冷杉亚科和落叶松亚科均不是单系类群，将松科划分为冷杉亚科、落叶松亚科和松亚科三个亚科的系统(郑万钧，傅立国，1978)是不自然的。 相似文献
10.
双参属Triplostegia Wall．ex DC．由分布于东南亚地区的2个种组成，为多年生草本植物。它的归属一直存在争议，有时置于川续断科Dipsacaceae或败酱科Valerianaceae，有时单立一科，即双参科Triplostegiaceae。本研究对广义川续断目Dipsacales s．l．的21种植物(分别来自于败酱科、川续断科、双参属、刺参属Morina、广义忍冬科Caprifoliaceae s. l．、五福花科 Adoxaceae)和外类群人参Panax schin-seng Nees．的叶绿体 DNA trnL-F区进行了测序，并建立系统发育树状图。结果显示，败酱科、川续断科、双参属、刺参属和广义忍冬科的4个属(双盾木属Dipelta、虫胃实属Kolkwitzia、六道木属Abelia和北极花属Linnaea)形成
了一个单系群并得到了很强的支持(100％ bootstrap)；双参属与川续断科有更近的关系，建议作为一个亚科置于川续断科；广义忍冬科为一多系类群；而刺参属与其他广义川续断目类群之间的关系尚不能确定。 相似文献
11.
We have used Brownian dynamics-finite element method (BD-FEM) to guide the optimization of a microfluidic device designed to stretch DNA for gene mapping. The original design was proposed in our previous study [C. C. Hsieh and T. H. Lin, Biomicrofluidics 5(4), 044106 (2011)] for demonstrating a new pre-conditioning strategy to facilitate DNA stretching through a microcontraction using electrophoresis. In this study, we examine the efficiency of the original device for stretching DNA with different sizes ranging from 48.5 kbp (λ-DNA) to 166 kbp (T4-DNA). The efficiency of the device is found to deteriorate with increasing DNA molecular weight. The cause of the efficiency loss is determined by BD-FEM, and a modified design is proposed by drawing an analogy between an electric field and a potential flow. The modified device does not only regain the efficiency for stretching large DNA but also outperforms the original device for stretching small DNA. 相似文献
12.
We present a lossless Deoxyribonucleic Acid (DNA) sequence hiding method that can be used for ensuring authenticity of DNA sequence in the context of Mobile Cloud based healthcare systems. Hiding data within DNA sequence results in permanent information loss in DNA sequence. Therefore, providing DNA sequence authenticity using data hiding is challenging. Moreover, existing works on DNA data hiding require a reference DNA sequence data to retrieve hidden data. Hence, current methods are not blind approaches and inappropriate for ensuring authenticity of DNA sequence in the Mobile Cloud. The proposed method hides authentication data within DNA sequence, extracts authentication data, and reconstructs the DNA sequence without any loss of information. From there, our proposed approach guarantees DNA sequence authenticity and integrity in Mobile Cloud based healthcare systems. We present a security analysis of our method to show that the method is secured. We conduct several experiments to demonstrate the performance of our proposed method. 相似文献
13.
Recently, we have reported the experimental results of DNA stretching by flow field in three microchannels (C. H. Lee and C. C. Hsieh, Biomicrofluidics 7(1), 014109 (2013)) designed specifically for the purpose of preconditioning DNA conformation for easier stretching. The experimental results do not only demonstrate the superiority of the new devices but also provides detailed observation of DNA behavior in complex flow field that was not available before. In this study, we use Brownian dynamics-finite element method (BD-FEM) to simulate DNA behavior in these microchannels, and compare the results against the experiments. Although the hydrodynamic interaction (HI) between DNA segments and between DNA and the device boundaries was not included in the simulations, the simulation results are in fairly good agreement with the experimental data from either the aspect of the single molecule behavior or from the aspect of ensemble averaged properties. The discrepancy between the simulation and the experimental results can be explained by the neglect of HI effect in the simulations. Considering the huge savings on the computational cost from neglecting HI, we conclude that BD-FEM can be used as an efficient and economic designing tool for developing new microfluidic device for DNA manipulation. 相似文献
14.
Vaishali Kolgiri Vidya Nagar Vinayak Patil 《Indian journal of clinical biochemistry : IJCB》2018,33(3):273-281
HIV-infected adults may be likely to have metabolic syndrome (MS) at younger ages and in the absence of obesity compared with general population. In the present study, we determined prevalence of MS and its association with oxidative deoxy nucleic acid (DNA) damage in HIV-1 infected patients with different ART status. We used plasma level of the oxidized base, 8-hydroxy-2-deoxyguanosine (8-OHdG), as a biomarker of oxidative DNA damage. To measure plasma 8-OHdG we used 8-OHdG enzyme-linked, immunosorbent assay. The biomarkers of MS were insulin resistance, Cholesterol/HDL ratio, Waist circumference and Hypertension. MS and oxidative DNA damage were significantly higher in HIV-positive patients with second line ART and first line ART than ART-naive patients. In a logistic regression analysis, increased MS was positively associated with the increased DNA damage (OR: 29.68, 95%:13.47, CI: 65.40) P = 0.0001. ART plays a significant role in the development of MS and oxidative DNA damage in HIV-positive patients taking antiretroviral therapy. Awareness and knowledge of MS and DNA damage in HIV/AIDS patients may prove helpful to clinicians to manage non-AIDS diseases such as cardiovascular disease and cancer. To determine exact role of ART in induction of MS and DNA damage larger studies are warranted. 相似文献
15.
DNA分子标记技术在水生动物遗传多样性研究中的应用 总被引：1，自引：0，他引：1
简要阐述了几种常见DNA分子标记技术,如限制性片断长度多态性(restriction fragment length polymorphism,RFLP)、随机扩增多态性DNA(random amplified polymorphie DNA,RAPD)、扩增片断长度多态性(amplified fragment length polymorphism,AFLP)、简单重复序列或微卫星标记(simpie sequencerepeat,SSR)、内部简单重复序列(inter-simple sequence repeat,ISSR)和单核苷酸多态性(single nucleotidepelymorphisms,SNP)等的基本原理、技术上的优缺点及其在水生动物遗传多样性研究中的应用,包括遗传多样性的鉴定、品种亲缘关系与分类的研究和种质资源的鉴定等.最后,对DNA分子标记技术在水生动物遗传多样性应用中的存在问题进行了简单的讨论. 相似文献
16.
Reactive oxygen species (ROS) are cytotoxic at higher concentration resulting in cell death, mutations, chromosomal aberrations
or carcinogenesis. In this study DNA was modified by singlet oxygen and superoxide anion radicals generated by illumination
of riboflavin under 365 nm UV-light. The modified DNA induced high titre antibodies in experimental animals. In enzyme immunoassay,
serum antibodies from cancer patients (n = 34) showed a higher recognition of the modified DNA, as compared to the native form. This was further confirmed by the
gel-shift assay. Immune IgG were used as a probe to detect oxidative lesions in the DNA of cancer patients. DNA isolated from
lymphocytes of cancer patients proved to be an appreciable inhibitor of the experimentally induced antibodies against the
ROS-DNA. This indicates the presence of oxidative lesions in the DNA obtained from cancer patients. The results show that
ROS induced oxidative damage to DNA in cancer patients generate neo-epitopes that are alien for the immune system, resulting in autoantibody formation. 相似文献
17.
Dielectrophoretic properties of DNA have been determined by measuring capacitance changes between planar microelectrodes. DNA sizes ranged from 100 bp to 48 kbp, DNA concentrations from below 0.1 to 70 μg∕ml. Dielectrophoretic spectra exhibited maximum response around 3 kHz and 3 MHz. The strongest response was found for very long DNA (above 10 kbp) and for short 100 bp fragments, which corresponds to the persistence length of DNA. The method allows for an uncomplicated, automatic acquisition of the dielectrophoretic properties of submicroscopical objects without the need for labeling protocols or optical accessibility. 相似文献
18.
Two simple gold nanoparticle (GNP)-based DNA analysis methods using a microfluidic device are presented. In the first method, probe DNA molecules are immobilized on the surface of a self-assembled submonolayer of GNPs. The hybridization efficiency of the target oligonulceotides was improved due to nanoscale spacing between probe molecules. In the second method, target DNA molecules, oligonulceotides or polymerase chain reaction (PCR) amplicons, are first bound to GNPs and then hybridized to the immobilized probe DNA on a glass slide. With the aid of GNPs, we have successfully discriminated, at room temperature, between two PCR amplicons (derived from closely related fungal pathogens, Botrytis cinerea and Botrytis squamosa) with one base-pair difference. DNA analysis on the microfluidic chip avoids the use of large sample volumes, and only a small amount of oligonucelotides (8 fmol) or PCR products (3 ng), was needed in the experiment. The whole procedure was accomplished at room temperature in 1 h, and apparatus for high temperature stringency was not required. 相似文献
19.
Size-dependent trajectories of DNA macromolecules due to insulative dielectrophoresis in submicrometer-deep fluidic channels 总被引：1，自引：0，他引：1
Gea O. F. Parikesit Anton P. Markesteijn Oana M. Piciu Andre Bossche Jerry Westerweel Ian T. Young Yuval Garini 《Biomicrofluidics》2008,2(2)
In this paper, we demonstrate for the first time that insulative dielectrophoresis can induce size-dependent trajectories of DNA macromolecules. We experimentally use λ (48.5 kbp) and T4GT7 (165.6 kbp) DNA molecules flowing continuously around a sharp corner inside fluidic channels with a depth of 0.4 μm. Numerical simulation of the electrokinetic force distribution inside the channels is in qualitative agreement with our experimentally observed trajectories. We discuss a possible physical mechanism for the DNA polarization and dielectrophoresis inside confining channels, based on the observed dielectrophoresis responses due to different DNA sizes and various electric fields applied between the inlet and the outlet. The proposed physical mechanism indicates that further extensive investigations, both theoretically and experimentally, would be very useful to better elucidate the forces involved at DNA dielectrophoresis. When applied for size-based sorting of DNA molecules, our sorting method offers two major advantages compared to earlier attempts with insulative dielectrophoresis: Its continuous operation allows for high-throughput analysis, and it only requires electric field strengths as low as ∼10 V∕cm. 相似文献