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A novel detection of single-stranded DNA binding protein based on ss-DNA modified chip using surface plasmon resonance microscopy
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作者 Jian Quan Lu Ming Bo Xu +2 位作者 Xing Wang Zhou Jin Guang Xu Qing Tao 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第4期441-444,共4页
An ss-DNA gold chip was prepared based on self-assembly of the thiol-derivatized oligonucleotide, and used for the determination of single-stranded binding protein (SSB) by surface plasmon resonance microscopy (SPR... An ss-DNA gold chip was prepared based on self-assembly of the thiol-derivatized oligonucleotide, and used for the determination of single-stranded binding protein (SSB) by surface plasmon resonance microscopy (SPR). The experiment results showed that SSB binds ss-DNA with high specificity, and relative signal of SPR response is proportional to the concentration of SSB in the range of 0.1-100 ng/mL with a detection limit (S/N = 3) of 0.07 ng/mL. 展开更多
关键词 DETECTION single-stranded dna binding protein ss-dna Surface plasmon resonance microscopy
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Structure and switching of single-stranded DNA tethered to a charged nanoparticle surface 被引量:1
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作者 赵新军 高志福 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期269-276,共8页
Using a molecular theory, we investigate the temperature-dependent self-assembly of single-stranded DNA(ss DNA)tethered to a charged nanoparticle surface. Here the size, conformations, and charge properties of ss DN... Using a molecular theory, we investigate the temperature-dependent self-assembly of single-stranded DNA(ss DNA)tethered to a charged nanoparticle surface. Here the size, conformations, and charge properties of ss DNA are taken into account. The main results are as follows: i) when the temperature is lower than the critical switching temperature, the ss DNA will collapse due to the existence of electrostatic interaction between ss DNA and charged nanoparticle surface; ii)for the short ss DNA chains with the number of bases less than 10, the switching of ss DNA cannot happen, and the critical temperature does not exist; iii) when the temperature increases, the electrostatic attractive interaction between ss DNA and charged nanoparticle surface becomes weak dramatically, and ss DNA chains will stretch if the electrostatic attractive interaction is insufficient to overcome the elastic energy of ss DNA and the electrostatic repulsion energy. These findings accord well with the experimental observations. It is predicted that the switching of ss DNA will not happen if the grafting densities are too high. 展开更多
关键词 molecular theory ss dna tethered to charged nanoparticle surface temperature-dependent switching
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The “3 Genomic Numbers” Discovery: How Our Genome Single-Stranded DNA Sequence Is “Self-Designed” as a Numerical Whole
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作者 Jean-Claude Perez 《Applied Mathematics》 2013年第10期37-53,共17页
This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the... This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the entire human genome. Beyond the evolution and erratic mutations like transposons within the genome, it’s as if the memory of a fossil genome with multiple symmetries persists. This recalls the “intermingling” of information characterizing the fractal universe of chaos theory. The result leads to a balanced and perfect tuning between the masses of the two strands of the huge DNA molecule that constitute our genome. We show here how codon populations forming the single-stranded DNA sequences can constitute a critical approach to the understanding of junk DNA function. Then, we suggest revisiting certain methods published in our 2009 book “Codex Biogenesis”. In fact, we demonstrate here how the universal genetic code table is a powerful analytical filter to characterize single-stranded DNA sequences constituting chromosomes and genomes. We can then show that any genomic DNA sequence is featured by three numbers, which characterize it and its 64 codon populations with correlations greater than 99%. The number “1” is common to all sequences, expressing the second law of Chargaff. The other 2 numbers are related to each specific DNA sequence case characterizing life species. For example, the entire human genome is characterized by three remarkable numbers 1, 2, and Phi = 1.618 the golden ratio. Associated with each of these three numbers, we can match three axes of symmetry, then “imagine” a kind of hyperspace formed by these codon populations. Then we revisit the value (3-Phi)/2 which is probably universal and common to both the scale of quarks and atomic levels, balancing and tuning the whole human genome codon population. Finally, we demonstrate a new kind of duality between “form and substance” overlapping the whole human genome: we will show that—simultaneously with the duality between genes and junk DNA—there is a second layer of embedded hidden structure overlapping all the DNA of the whole human genome, dividing it into a second type of duality information/redundancy involving golden ratio proportions. 展开更多
关键词 Genetic Code CODON Populations Junk dna Cancer Genomics Chromosomal Translocations Genomes Diversity Chromosomes Diversity WHOLE Human GENOME dna SEQUENCE “Phi” the Golden Ratio Fibonacci NUMBERS Information Theory SYMMETRY Cellular Automata Chargaff’s CODON Level SYMMETRY Principle Fractal Self-Similarity “e” Euler’s Number “Pi” form and Substance Redundancy Encryption
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Determination of double-and single-stranded DNA breaks in bovine sperm is predictive of their fertilizing capacity
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作者 Jordi Ribas‑Maynou Ariadna Delgado‑Bermúdez +4 位作者 Yentel Mateo‑Otero Estel Vinolas Carlos O.Hidalgo WSteven Ward Marc Yeste 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期134-151,共18页
Background:The analysis of chromatin integrity has become an important determinant of sperm quality.In frozenthawed bovine sperm,neither the sequence of post-thaw injury events nor the dynamics of different types of s... Background:The analysis of chromatin integrity has become an important determinant of sperm quality.In frozenthawed bovine sperm,neither the sequence of post-thaw injury events nor the dynamics of different types of sperm DNA breaks are well understood.The aim of the present work was to describe such sperm degradation aftermath focusing on DNA damage dynamics,and to assess if this parameter can predict pregnancy rates in cattle.Results:A total of 75 cryopreserved ejaculates from 25 Holstein bulls were evaluated at two post-thawing periods(0-2 h and 2-4 h),analyzing global and double-stranded DNA damage through alkaline and neutral Comet assays,chromatin deprotamination and decondensation,sperm motility,viability,acrosomal status,and intracellular levels of total ROS,superoxides and calcium.Insemination of 59,605 females was conducted using sperm from the same bulls,thus obtaining the non-return to estrus rates after 90 d(NRR).Results showed an increased rate of double-stranded breaks in the first period(0-2 h:1.29±1.01%/h vs.2-4 h:0.13±1.37%/h;P<0.01),whereas the rate of sperm with moderate+high single-stranded breaks was higher in the second period(0-2 h:3.52±7.77%/h vs.2-4h:21.06±11.69%/h;P<0.0001).Regarding sperm physiology,viability decrease rate was different between the two periods(0-2 h:-4.49±1.79%/h vs.2-4 h:-2.50±3.39%/h;P=0.032),but the progressive motility decrease rate was constant throughout post-thawing incubation(0-2 h:-4.70±3.42%/h vs.2-4 h:-1.89±2.97%/h;P>0.05).Finally,whereas no correlations between bull fertility and any dynamic parameter were found,there were correlations between the NRR and the basal percentage of highly-damaged sperm assessed with the alkaline Comet(Rs=-0.563,P=0.003),between NRR and basal progressive motility(Rs=0.511,P=0.009),and between NRR and sperm with high ROS at 4 h post-thaw(Rs=0.564,P=0.003).Conclusion:The statistically significant correlations found between intracellular ROS,sperm viability,sperm motility,DNA damage and chromatin deprotamination suggested a sequence of events all driven by oxidative stress,where viability and motility would be affected first and sperm chromatin would be altered at a later stage,thus suggesting that bovine sperm should be used for fertilization within 2 h post-thaw.Fertility correlations supported that the assessment of global DNA damage through the Comet assay may help predict bull fertility. 展开更多
关键词 Cattle CHROMATIN Comet test dna damage FERTILITY SPERM Sperm quality
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Replication of M13 single-stranded DNA bearing a sitespecific ethenocytosine lesion by Escherichia coil cell extracts
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作者 WANGGE PAULMDUNMAN MZAFRIHUMAYUN 《Cell Research》 SCIE CAS CSCD 1997年第1期1-12,共12页
Previous investigation on the mutagenic effects of 3,N4-Ethenocytosine (εC), a nonpairing DNA lesion,revealed the existence of a novel SOS-independent inducible mutagenic mechanism in E. coli termed UVM for UV modula... Previous investigation on the mutagenic effects of 3,N4-Ethenocytosine (εC), a nonpairing DNA lesion,revealed the existence of a novel SOS-independent inducible mutagenic mechanism in E. coli termed UVM for UV modulation of mutagenesis. To investigate whether UVM is mediated by an alteration of DNA replication, we have set up an in vitro replication system ill which phage M13 viral single-stranded DNA bearing a single site-specific (εC) residue is replicated by soluble protein extracts from E. coli cells. Replication products were analyzed by agarose gel electrophoresis and the frequency of translesion synthesis was determined by restriction endonuclease analyses. Our data indicate that DNA replication is strongly inhibited by εC, but that translesion DNA synthesis does occur in about 14% of the replicated DNA molecules. These results are very similar to those observed previously in vivo, and suggest that this experimental system may be suitable for evaluating alterations in DNA replication in UVM-induced cells. 展开更多
关键词 Ethenocytosine M13 in vitro replication cell extract
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Circular Single-Stranded DNA for Simultaneous Suppression of Multiple miRNAs
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作者 Yufan Pan Xin Li +9 位作者 Liangzhi Luo Rui Xu Chenyou Zhu Sijie He Jun Wu Ruofan Chen Yifan Jiang Yuanchen Dong Ziyang Hao Dongsheng Liu 《CCS Chemistry》 2026年第1期441-452,共12页
MicroRNA-based therapeutics,particularly antimiRNA oligonucleotides(AMOs),have emerged as promising agents for cancer treatment.However,the intrinsic bio-instability of linear AMOs has posed a significant challenge to... MicroRNA-based therapeutics,particularly antimiRNA oligonucleotides(AMOs),have emerged as promising agents for cancer treatment.However,the intrinsic bio-instability of linear AMOs has posed a significant challenge to their development.Herein,we present an innovative strategy employing enzymatically synthesized circular single-stranded DNA to achieve simultaneous suppression of multiple oncogenic miRNAs.Our one-pot-synthesized 132-nt circular AMO demonstrated enhanced exonuclease resistance,thereby significantly improving intracellular stability compared with its linear counterparts.Concurrently,the circular topology enabled simultaneous suppression of four oncogenic miRNAs(miR-21/221/155/10b)through the RNase H-dependent cleavage mechanism.Such synergistic inhibition can upregulate tumor suppressor mRNAs(PTEN,HIPK2,SOCS1,and HOXD10),effectively curtailing both proliferation and migration of MCF-7 cells.This chemical modification-free platform not only addresses the inherent stability issues of nucleic acid-based therapies but also establishes a versatile paradigm for multitargeted oligonucleotide therapeutics. 展开更多
关键词 anti-miRNA oligonucleotide circular dna miRNA therapy multitarget therapy tumor suppression
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A circular single-stranded DNA mycovirus infects plants and confers broad-spectrum fungal resistance 被引量:2
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作者 Xianhong Wang Ioly Kotta-Loizou +9 位作者 Robert H.A.Coutts Huifang Deng Zhenhao Han Ni Hong Karim Shafik Liping Wang Yashuang Guo Mengmeng Yang Wenxing Xu Guoping Wang 《Molecular Plant》 SCIE CSCD 2024年第6期955-971,共17页
Circular single-stranded DNA(ssDNA)viruses have been rarely found in fungi,and the evolutionary and ecological relationships among ssDNA viruses infecting fungi and other organisms remain unclear.In this study,a novel... Circular single-stranded DNA(ssDNA)viruses have been rarely found in fungi,and the evolutionary and ecological relationships among ssDNA viruses infecting fungi and other organisms remain unclear.In this study,a novel circular ssDNA virus,tentatively named Diaporthe sojae circular DNA virus 1(DsCDV1),was identified in the phytopathogenic fungus Diaporthe sojae isolated from pear trees.DsCDV1 has a monopartite genome(3185 nt in size)encapsidated in isometric virions(21-26 nm in diameter).The genome comprises seven putative open reading frames encoding a discrete replicase(Rep)split by an intergenic region,a putative capsid protein(CP),several proteins of unknown function(P1-P4),and a long intergenic region.Notably,the two split parts of DsCDV1 Rep share high identities with the Reps of Geminiviridae and Genomoviridae,respectively,indicating an evolutionary linkage with both families.Phylogenetic analysis based on Rep or CP sequences placed DsCDV1 in a unique cluster,supporting the establishment of a new family,tentatively named Gegemycoviridae,intermediate to both families.DsCDV1 significantly attenuates fungal growth and nearly erases fungal virulence when transfected into the host fungus.Remarkably,DsCDV1 can systematically infect tobacco and pear seedlings,providing broad-spectrum resistance to fungal diseases.Subcellular localization analysis revealed that DsCDV1 P3 is systematically localized in the plasmodesmata,while its expression in trans-complementation experiments could restore systematic infection of a movement-deficient plant virus,suggesting that P3 is a movement protein.DsCDV1 exhibits unique molecular and biological traits not observed in other ssDNA viruses,serving as a link between fungal and plant ssDNA viruses and presenting an evolutionary connection between ssDNA viruses and fungi.These findings contribute to expanding our understanding of ssDNA virus diversity and evolution,offering potential biocontrol applications for managing crucial plant diseases. 展开更多
关键词 circular single-stranded dna virus MYCOVIRUS virus evolution Genomoviridae Gegemycoviridae Diaporthe sojae circular dna virus 1
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Single-stranded RNA as primers of terminal deoxynucleotidyl transferase for template-independent DNA polymerization
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作者 Houyu Han Jingyu Cui +7 位作者 Dianming Zhou Deping Hua Weipan Peng Mengyao Lin Yating Zhang Fangya Li Xiaoqun Gong Jianyu Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第2期161-164,共4页
Terminal deoxynucleotidyl transferase(Td T) has been characterized as template-independent polymerase using single-stranded DNA(ss DNA) as primers to generate random oligonucleotides. However, the extension performanc... Terminal deoxynucleotidyl transferase(Td T) has been characterized as template-independent polymerase using single-stranded DNA(ss DNA) as primers to generate random oligonucleotides. However, the extension performance of Td T to single-stranded RNA(ss RNA) is vague. By systematically comparing and contrasting the performance of Td T-catalyzed ss DNA and ss RNA extension, it is indicated that the catalytic efficiency of ss RNA as primers was about 3 times lower than ss DNA as primers. Collectively, it is believed that understanding the catalytic performance of Td T will help to design the strategy to synthesize chimeric DNA on 3-OH of ss RNA, which becomes invaluable. 展开更多
关键词 Terminal deoxynucleotidyl transferase single-stranded RNA single-stranded dna Template-independent POLYMERIZATION
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基于环境DNA技术的元江鱼类生物多样性研究
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作者 朱书礼 陈蔚涛 +3 位作者 李跃飞 武智 李捷 刘亚秋 《南方水产科学》 北大核心 2026年第1期60-73,共14页
元江是云南地区最主要的河流之一,拥有丰富的鱼类资源,近年来受人类活动影响,元江鱼类资源呈衰退趋势。本研究通过利用环境DNA(Environmental DNA,eDNA)技术对元江鱼类进行调查,为元江鱼类资源管理和保护提供基础数据。2023年10月在元... 元江是云南地区最主要的河流之一,拥有丰富的鱼类资源,近年来受人类活动影响,元江鱼类资源呈衰退趋势。本研究通过利用环境DNA(Environmental DNA,eDNA)技术对元江鱼类进行调查,为元江鱼类资源管理和保护提供基础数据。2023年10月在元江设置了16个站位采集水样,共检出鱼类47种,隶属于5目15科40属,包括红(鱼丕)(Bagarius rutilus)和斑鳠(Hemibagrus guttatus)等珍稀濒危鱼类,并检出8种外来鱼类。α多样性分析显示,各站位Shannon-Wiener指数为0.92~2.41,Simpson指数为0.44~0.88,Pielou均匀度指数为0.35~0.60,Margalef指数为0.30~1.16。采用层次聚类(Cluster)和非度量多维尺度分析(NMDS)方法对鱼类群落空间分布特征进行分析,结果显示鱼类群落在空间分布上存在差异,各站位从下游至上游分为3组,表现为在地理空间上相近的站位聚在一起。通过相似性百分比分析(SIMPER)物种对各组间差异的贡献,结果表明翘嘴鲌(Culter alburnus)、宽额鳢(Channa gachua)、鲮(Cirrhinus molitorella)和棒花鱼(Abbottina rivularis)等是造成各组间差异的主要种类。采用冗余分析方法(RDA)分析了鱼类多样性与环境因子的关系,发现元江鱼类群落主要受海拔、盐度、电导率、总溶解固体、氧化还原电位和总磷等环境因子影响。研究表明,环境DNA技术可有效分析元江鱼类的种类组成和分布,是开展元江鱼类生物多样性监测和保护的重要手段。 展开更多
关键词 环境dna(edna) 鱼类多样性 群落结构 环境因子 元江
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基于共价闭合环状DNA动力学的慢性乙型肝炎治疗策略
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作者 胡接力 黄爱龙 《临床肝胆病杂志》 北大核心 2026年第1期14-20,共7页
实现慢性乙型肝炎病毒(HBV)感染的普遍治愈,是乙型肝炎研究领域的最高目标。深入探索HBV感染治愈的可能途径,对于明确关键研究方向具有重要意义。共价闭合环状DNA(cccDNA)作为HBV复制循环中最难以被清除的遗传物质,既是实现治愈的主要障... 实现慢性乙型肝炎病毒(HBV)感染的普遍治愈,是乙型肝炎研究领域的最高目标。深入探索HBV感染治愈的可能途径,对于明确关键研究方向具有重要意义。共价闭合环状DNA(cccDNA)作为HBV复制循环中最难以被清除的遗传物质,既是实现治愈的主要障碍,也是构建治愈策略分析框架的核心基点。本文在概述“cccDNA动力学”思维框架的基础上,进一步阐释其核心内涵,并以此为依据系统探讨论述促进cccDNA衰减的关键策略。 展开更多
关键词 乙型肝炎病毒 共价闭合环状dna 治疗学
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基于形态学和DNA条形码的青藏高原东缘鼢鼠物种鉴定
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作者 蔡振媛 孔虹颖 +8 位作者 何振邦 宋鹏飞 郭凡 李斌 梁程博 胡天石 徐波 林中原 张同作 《兽类学报》 北大核心 2026年第1期116-128,共13页
物种分类和鉴定是生物学研究的基石,综合分子生物学和经典分类学方法进行物种鉴定可提高结果可靠性。本研究采用传统形态学和线粒体细胞色素b基因(Cyt b)序列对青藏高原东缘青海省海东市平安区采集的74个鼢鼠样本进行物种鉴定。头骨形... 物种分类和鉴定是生物学研究的基石,综合分子生物学和经典分类学方法进行物种鉴定可提高结果可靠性。本研究采用传统形态学和线粒体细胞色素b基因(Cyt b)序列对青藏高原东缘青海省海东市平安区采集的74个鼢鼠样本进行物种鉴定。头骨形态鉴定结果显示,尾巴被稀疏短白毛的鼢鼠个体(Pac)为甘肃鼢鼠(Eospalax cansus),而尾巴被密毛的个体(Pab)为高原鼢鼠(Eospalax baileyi)。74个鼢鼠样本的Cyt b序列共定义了25个单倍型,结合GenBank中8种鼢鼠的Cyt b序列进行分析,在构建的系统发育树中,已知8种鼢鼠序列各自聚为1个单系群,平安区Pab的16个单倍型与已知高原鼢鼠聚为一支,Pac的8个单倍型与已知甘肃鼢鼠聚为一支。遗传距离结果显示,Pac与已知甘肃鼢鼠遗传距离小于与其他物种的遗传距离(P<0.001),Pab与已知高原鼢鼠的遗传距离小于与其他物种的遗传距离(P<0.001)。Cyt b基因分析和形态鉴定结果一致,Cyt b是鼢鼠鉴定的一个有效的DNA条形码基因。综合形态学和DNA条形码鉴定结果,平安区分布着2种鼢鼠:甘肃鼢鼠和高原鼢鼠。在地理分布上,甘肃鼢鼠主要分布在平安区北部邻近黄土高原海拔相对较低的区域,高原鼢鼠则分布在南部邻近青藏高原海拔相对较高的区域。本研究加深了对平安区鼢鼠物种组成和分布特征的了解,并为解决鼢鼠物种形态鉴定难的问题提供了DNA条形码解决方案。 展开更多
关键词 dna条形码技术 鼢鼠 Cyt b 形态 系统发育 遗传距离
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两个镍配合物的结构、抑菌活性及与DNA的相互作用
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作者 季甲 姚腾奇 +5 位作者 邓文钱 石文婧 吕璇 田琳 辛晓艳 侯银玲 《无机化学学报》 北大核心 2026年第1期78-86,共9页
通过原位反应,设计合成了2例配合物[Ni(HL_(1))_(2)]·CH_(3)CN·CH_(3)OH(1)和[Ni(L2)2](2),其中H_(2)L_(1)=2-羟基苯甲酸(6-甲氧基-吡啶-2-基亚甲基)-肼,HL2=4-溴-2-[(6-甲氧基吡啶-2-基亚甲基)-氨基]-苯酚。单晶X射线衍射分... 通过原位反应,设计合成了2例配合物[Ni(HL_(1))_(2)]·CH_(3)CN·CH_(3)OH(1)和[Ni(L2)2](2),其中H_(2)L_(1)=2-羟基苯甲酸(6-甲氧基-吡啶-2-基亚甲基)-肼,HL2=4-溴-2-[(6-甲氧基吡啶-2-基亚甲基)-氨基]-苯酚。单晶X射线衍射分析表明:配合物1和2均具有以二价镍离子为中心的单核零维结构。打孔抑菌圈实验数据表明,与单纯的过渡金属镍离子相比,配合物1和2表现出更强的抑菌活性。采用紫外可见光谱法、循环伏安法和荧光光谱法研究了配合物1和2与小牛胸腺DNA(CTDNA)之间的相互作用,结果表明2个配合物均通过插入作用模式与CTDNA结合。 展开更多
关键词 Ni配合物 原位合成 晶体结构 生物活性 dna相互作用
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基于环境DNA的河-湖水生态调查与评估研究进展
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作者 魏源送 蔡佳琳 +5 位作者 谢阳村 张耀方 程楷文 薛万来 魏明海 张俊亚 《环境科学学报》 北大核心 2026年第1期1-22,共22页
环境DNA(eDNA)技术通过分析环境样品中的遗传物质,为水生态监测与评估带来了革命性进展,实现了非侵入性、高灵敏度及多物种同步检测.本综述系统梳理并总结了近年来eDNA技术在河湖水生态调查与评估应用全链条—从eDNA信号的产生与环境行... 环境DNA(eDNA)技术通过分析环境样品中的遗传物质,为水生态监测与评估带来了革命性进展,实现了非侵入性、高灵敏度及多物种同步检测.本综述系统梳理并总结了近年来eDNA技术在河湖水生态调查与评估应用全链条—从eDNA信号的产生与环境行为到样本采集、实验分析、数据解读及模型应用的关键研究进展,并剖析了面临的核心科学问题与技术挑战.当前,eDNA技术在生物多样性评估、濒危物种追踪、外来种入侵预警及生态修复评价等方面已展现出显著应用潜力,但其可靠性与推广仍面临eDNA信号环境动态复杂、参考数据库不完整、引物通用性与特异性难以兼顾、以及生物信息分析流程标准化不足等挑战.区别于其它综述,本文不仅全面覆盖各环节的现状与瓶颈,更从标准化建设、技术方法革新、数据资源共享、多源信息融合及智能化决策支持等维度,前瞻性地展望了该领域未来的发展方向与系统性解决方案的构建框架,以期为科研工作者深入把握eDNA技术的最新进展与未来趋势提供参考,从而助力该领域的技术优化与标准化进程. 展开更多
关键词 环境dna(edna) 水生态系统 生物多样性监测 宏条形码 参考数据库 标准化
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补肾方剂治疗男性不育症患者精子DNA损伤的系统综述和meta分析
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作者 刘涛 赵琦 +4 位作者 杨朝旭 徐琰 孙志兴 陈赟 陈建淮 《中华男科学杂志》 2026年第1期52-60,共9页
目的运用meta分析方法系统评价补肾方剂治疗男性不育症患者精子DNA损伤(SDF)的有效性和安全性。方法从中国知网、维普、万方、PubMed、Cochrane Library、Embase、Web of Science数据库中检索补肾方剂改善SDF的随机对照试验(RCT)研究,... 目的运用meta分析方法系统评价补肾方剂治疗男性不育症患者精子DNA损伤(SDF)的有效性和安全性。方法从中国知网、维普、万方、PubMed、Cochrane Library、Embase、Web of Science数据库中检索补肾方剂改善SDF的随机对照试验(RCT)研究,对文献进行方法学质量评价,运用RevMan5.3.5软件进行meta分析,并对结局指标进行GRADE质量分级。结果共纳入17项RCT研究,涉及2164例男性患者。与西医常规治疗相比,补肾方剂能够显著改善男性不育症患者DNA碎片指数(DFI)(MD=-6.50,95%CI:-7.88~-5.11,P<0.01),提高配偶妊娠率(RR=2.11,95%CI:1.12~4.00,P=0.87)、精子总活率(MD=5.56,95%CI:4.39~6.74,P<0.01)、前向运动精子百分率(MD=6.82,95%CI:5.62~8.03,P<0.01)、精子浓度(MD=6.51,95%CI:3.81~9.21,P<0.01)和正常形态精子百分率(MD=1.26,95%CI:0.45~2.06,P<0.01),且补肾方剂不会增加不良反应的发生。结论低到中等质量证据表明,与西医常规治疗相比,补肾方剂在改善男性不育症患者DFI、精液参数、配偶妊娠率等方面具有一定优势,且安全性较好。 展开更多
关键词 精子dna损伤 精子dna碎片指数 男性不育症 补肾方剂 META分析
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基于周期阻滞和氧化⁃抗氧化失衡研究槟榔碱致小鼠骨髓细胞DNA损伤的机制
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作者 于蕾 于晶涵 +6 位作者 宋辉 郎朗 马瑗晗 龚艳朝 张小坡 张彩云 王正文 《海南医科大学学报》 北大核心 2026年第2期89-95,共7页
目的:研究槟榔碱(arecoline,ARC)体内对小鼠骨髓细胞DNA的损伤作用,并探讨其作用机制。方法:采用单细胞凝胶电泳实验分析ARC对小鼠骨髓细胞DNA损伤作用。采用流式细胞术、DCFH-DA荧光染色、罗丹明123染色等方法对小鼠骨髓细胞的细胞周期... 目的:研究槟榔碱(arecoline,ARC)体内对小鼠骨髓细胞DNA的损伤作用,并探讨其作用机制。方法:采用单细胞凝胶电泳实验分析ARC对小鼠骨髓细胞DNA损伤作用。采用流式细胞术、DCFH-DA荧光染色、罗丹明123染色等方法对小鼠骨髓细胞的细胞周期,超氧化物歧化酶(superoxide dismutase,SOD)活性和谷胱甘肽(glutathione,GSH)、丙二醛(malondial dehyde,MDA)、活性氧(reactive oxygen species,ROS)含量,线粒体膜电位(Δψm),p53蛋白含量进行分析。结果:给予ARC1/2 LD_(50)剂量可引起小鼠骨髓细胞DNA损伤,与空白组相比拖尾现象较严重。随着ARC给药剂量的增加,G_(0)/G_(1)期的细胞比例明显增加(P<0.01),使骨髓细胞周期停滞在G_(0)/G_(1)期。ARC作用小鼠骨髓细胞后,SOD活性和GSH含量明显降低(P<0.01),MDA和ROS含量明显升高(P<0.01),并且随着ARC浓度增加,Δψm明显降低(P<0.01)。ARC给药组骨髓细胞内p53蛋白含量随给药剂量的增加而明显升高(P<0.01),呈一定的剂量依赖关系。结论:ARC能造成小鼠骨髓细胞DNA损伤,可增加p53蛋白表达诱导小鼠骨髓细胞周期阻滞在G_(0)/G_(1)期,引起Δψm降低,ROS增加,脂质过氧化增强,抗氧化功能受到严重损害,氧化和抗氧化失衡,这些是ARC引起小鼠骨髓细胞DNA损伤的机制。 展开更多
关键词 槟榔碱 骨髓细胞 dna损伤 G_(0)/G_(1)期阻滞 氧化-抗氧化失衡
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阿昔洛韦抑制EB病毒裂解引发的DNA损伤
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作者 刘剑 姚友恒 +2 位作者 邱红梅 刘益飞 李燊 《交通医学》 2026年第1期6-8,12,共4页
目的:研究阿昔洛韦抑制EB病毒裂解引发的DNA损伤作用。方法:以人类伯基特淋巴瘤细胞系Akata与Daudi细胞为研究对象,对照组采用200 nmol/L佛波酯(12-O-tetradecanoylphorbol 13-acetate,TPA)诱导Akata细胞,200 nmol/L TPA联合3 mmol/L丁... 目的:研究阿昔洛韦抑制EB病毒裂解引发的DNA损伤作用。方法:以人类伯基特淋巴瘤细胞系Akata与Daudi细胞为研究对象,对照组采用200 nmol/L佛波酯(12-O-tetradecanoylphorbol 13-acetate,TPA)诱导Akata细胞,200 nmol/L TPA联合3 mmol/L丁酸钠(sodium butyrate,NaB)诱导Daudi细胞0、6、24和48 h,实验组再同时向培养基中加入50μmol/L阿昔洛韦共孵育48 h。采用实时荧光定量PCR(RT-qPCR)法测定细胞中EB病毒裂解基因BZLF1、BMRF1和BLLF1的表达水平;采用Western Blot法测定细胞中BZLF1、γH2AX蛋白表达水平。结果:TPA和NaB诱导Akata和Daudi细胞0、6、24和48 h后,细胞中BZLF1、BMRF1和BLLF1基因表达水平较诱导前显著增加,差异均有统计学意义(P<0.05)。Western Blot结果显示,Akata细胞和Daudi细胞中EB病毒由潜伏转为裂解状态后,BZLF1与DNA损伤相关蛋白γH2AX表达显著增加,阿昔洛韦干预后γH2AX与BZLF1蛋白表达显著降低。结论:阿昔洛韦可抑制EB病毒裂解引发的DNA损伤,为阿昔洛韦治疗EB病毒相关疾病提供新思路。 展开更多
关键词 阿昔洛韦 EB病毒 裂解 dna损伤
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科学思维视角下的高中生物学情境教学研究——以“重组DNA技术的基本工具”教学为例
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作者 刘会坚 魏梅红 《福建基础教育研究》 2026年第1期134-136,140,共4页
根据建构主义学习理论有关情境教学论述,以“重组DNA技术的基本工具”教学为例,通过创设系列任务情境,激发学生认知冲突,引导学生动手构建模型,深化理解。通过探究、质疑、评价与反思,突破学习难点,优化思维路径,培养学生归纳与概括、... 根据建构主义学习理论有关情境教学论述,以“重组DNA技术的基本工具”教学为例,通过创设系列任务情境,激发学生认知冲突,引导学生动手构建模型,深化理解。通过探究、质疑、评价与反思,突破学习难点,优化思维路径,培养学生归纳与概括、模型与建模、批判性思维、创造性思维等科学思维。 展开更多
关键词 科学思维 情境教学 重组dna技术 建模 批判性思维
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自己“组装”DNA链置换计算机——人工智能和仿真软件支持下的跨学科学习案例
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作者 陈凯 《中国信息技术教育》 2026年第1期27-31,共5页
DNA链置换是实现分子逻辑门进而实现较复杂的DNA计算的一种方法,DNA计算问题天然具有跨学科特征,人工智能工具和仿真软件的支持,对学习者在实施相关跨学科学习过程中消除学科壁垒、降低认知负荷起到很大的作用。本文以构造2-4二进制解... DNA链置换是实现分子逻辑门进而实现较复杂的DNA计算的一种方法,DNA计算问题天然具有跨学科特征,人工智能工具和仿真软件的支持,对学习者在实施相关跨学科学习过程中消除学科壁垒、降低认知负荷起到很大的作用。本文以构造2-4二进制解码器为例,阐述和分析在当前已有技术支持下,生成式人工智能工具和仿真软件在DNA计算相关跨学科学习过程中可能发挥的作用、优势以及弱点。 展开更多
关键词 dna链置换 生成式人工智能 仿真软件
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人工智能在DNA设计中的研究进展
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作者 刘欢 郭发旭 +4 位作者 赵晓燕 黄龙雨 王健 周国民 张建华 《生物技术通报》 北大核心 2026年第1期51-66,共16页
DNA设计是根据特定功能需求定向构建与优化基因组功能元件,已成为合成生物学与精准育种等前沿领域的关键核心技术。传统设计方法受限于对复杂调控网络认知不足及序列搜索空间巨大等瓶颈,难以实现高效、精准的序列创新。近年来,人工智能... DNA设计是根据特定功能需求定向构建与优化基因组功能元件,已成为合成生物学与精准育种等前沿领域的关键核心技术。传统设计方法受限于对复杂调控网络认知不足及序列搜索空间巨大等瓶颈,难以实现高效、精准的序列创新。近年来,人工智能技术,特别是深度生成模型与预测模型的融合应用,正深刻重塑DNA设计的理论基础与技术范式。该范式通过学习海量组学数据中蕴含的“调控语法”,能够在超长基因组序列背景下实现高分辨率的功能预测、多模态信息整合与条件可控的序列生成。本文系统综述了人工智能在DNA设计中的前沿进展,重点阐述了深度生成与预测模型在启动子、增强子等多层级调控元件设计、序列优化及作物育种等领域的关键技术路径与应用实例。通过构建“设计—预测—优化—验证”的智能化闭环,人工智能不仅显著提升了复杂功能元件的设计效率与准确性,更催生了性能超越天然元件的“超天然”序列。展望未来,随着人工智能与合成生物学、实验自动化等领域的深度融合,DNA设计有望实现从智能化设计到高通量实验验证的完整闭环,从而加速生命科学基础研究与现代农业育种等领域的创新突破。 展开更多
关键词 人工智能 dna设计 生成模型 预测模型
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高品质花生DNA提取:CTAB法改良及多维度品质评价
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作者 田冬冬 杜龙 +3 位作者 赵星睿 王柏林 刘爱民 曲明静 《花生学报》 北大核心 2026年第1期123-132,共10页
花生叶片富含多酚、多糖及其他次生代谢物,常规方法或商品化试剂盒无法从中提取高品质DNA,严重阻碍了花生分子生物学研究。本研究以传统CTAB法为基础,根据CTAB裂解液各组分在DNA提取过程中所发挥的作用,以及细胞中DNA和多酚、多糖等物... 花生叶片富含多酚、多糖及其他次生代谢物,常规方法或商品化试剂盒无法从中提取高品质DNA,严重阻碍了花生分子生物学研究。本研究以传统CTAB法为基础,根据CTAB裂解液各组分在DNA提取过程中所发挥的作用,以及细胞中DNA和多酚、多糖等物质在空间上的相分离特性,进行改良优化。首先用PVP和高浓度EDTA组成预处理液,对花生组织进行预处理,从源头上阻断酚类氧化,去除过量多酚、多糖等杂质的同时,有效降低了花生叶片组织黏度;再用高浓度CTAB(3×)裂解液对预处理后的花生组织进行裂解,可以彻底清除蛋白及中性多糖等杂质。结果表明,相比传统CTAB法,改良CTAB法提取的花生叶片基因组DNA纯度极高,OD_(260)/OD_(280)值为1.8~1.9,OD_(260)/OD_(230)值大于2.0,并且提取结果稳定性好;DNA完整性高,能有效扩增出4 kb左右大片段DNA序列;DNA稳定性得到提升,室温(25℃)放置2个月无明显降解迹象。同时,改良CTAB法DNA提取效率大大提升,10 mg叶片即可获得3μg总DNA,即使使用衰老叶片也能高效提取到高品质DNA。上述研究表明,改良CTAB法提高了花生基因组DNA的纯度、完整性、稳定性和提取效率,适合应用于花生分子生物学研究,尤其是珍稀材料的遗传鉴定,同时为富含多酚、多糖等次生代谢产物样本DNA的提取提供了重要参考。 展开更多
关键词 花生叶片 dna提取 改良CTAB法 多酚 多糖
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