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早期卵子发生中P小体募集NANOS3的机制
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作者 耿鉴薇 何飞 +2 位作者 马一丹 周永睿 穆欣艺 《解剖学报》 2025年第3期323-328,共6页
目的 探讨早期卵子发生过程中卵母细胞内NANOS3与P小体(P-bodies)之间的关系以及两者相互作用的机制。方法 通过免疫荧光观察新生1日(1dpp)小鼠卵巢卵母细胞中NANOS3和死盒解旋酶6(DDX6)的共定位情况,并利用免疫共沉淀检测两者的相互作... 目的 探讨早期卵子发生过程中卵母细胞内NANOS3与P小体(P-bodies)之间的关系以及两者相互作用的机制。方法 通过免疫荧光观察新生1日(1dpp)小鼠卵巢卵母细胞中NANOS3和死盒解旋酶6(DDX6)的共定位情况,并利用免疫共沉淀检测两者的相互作用。构建NANOS3和DDX6全长质粒转染HEK293T细胞,通过免疫荧光和免疫共沉淀探讨两者相互作用的机制。NANOS3转染HeLa细胞,通过活细胞成像探究NANOS3是否具有液-液相分离(LLPS)的能力。通过DDX6-免疫沉淀-质谱联用技术(DDX6-IP-MS)鉴定早期卵子发生中P小体募集的蛋白。结果 在1dpp小鼠卵母细胞中NANOS3与DDX6共定位并能够相互作用。然而,转染NANOS3和DDX6的HEK293T细胞却无法观察到两者的共定位,但免疫共沉淀仍显示两者存在相互作用。同时,活细胞成像显示,NANOS3在细胞中具有动态的液体样性质,可能通过LLPS促进P小体的形成。最后,DDX6-IP-MS揭示DDX6可能通过结合NANOS3相互作用蛋白Pumilio,将NANOS3募集到P小体中。结论 NANOS3是新生小鼠卵母细胞中P小体的特定组分,可能参与调控早期卵子发生。 展开更多
关键词 nanos3 P小体 早期卵子发生 免疫荧光 新生小鼠
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Nanosizing enhancement of hydrogen storage performance and mechanism in Mg-based materials:Nano-substrate modulation,nano-catalyst construction,and nano-catalytic mechanisms
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作者 Duode Zhao Xiaojiang Hou +8 位作者 Yu Ge Dongfeng Sun Danting Li Chenlu Wang Xinlei Xie Peixuan Zhu Xiaohui Ye Guoquan Suo Yanling Yang 《Journal of Energy Chemistry》 2025年第10期609-636,共28页
The magnesium-based materials are acknowledged as one of the most promising solid-state hydrogen storage mediums,attributed to their superior hydrogen storage capacity.Nevertheless,challenges such as sluggish kinetics... The magnesium-based materials are acknowledged as one of the most promising solid-state hydrogen storage mediums,attributed to their superior hydrogen storage capacity.Nevertheless,challenges such as sluggish kinetics,thermodynamic stability,inadequate cycling stability,and difficulties in activation impede the commercial utilization of Mg-based composites.Research indicates that reducing material dimensions to the nanoscale represents an efficacious strategy to address these issues.In this work,we systematically analyze the impact of nanosizing on Mg-based composites from three perspectives:nano-substrate modulation,nano-catalyst construction,and nano-catalytic mechanism.This analysis aims to provide guidance for the optimization and development of nanosizing strategies.For the regulation of nanosizing of Mg-based composites,the nanosizing of multi-element micro-alloyed Mg-rich systems,the integrated synthesis of multi-element multi-component nano-catalysts,and the coexistence of multiple nano-catalytic mechanisms are proposed in the light of the current state of the art research,artificial intelligence technology,and advanced characterization technology to achieve efficient,multidimensional,and simultaneous regulation of the hydrogen storage performance of Mg-based composites.This paper also envisions future directions and potential applications,emphasizing the importance of interdisciplinary approaches that integrate material science,chemistry,and computational modeling to overcome existing limitations and unlock the full potential of Mg-based hydrogen storage technologies. 展开更多
关键词 nanosizing Mg-based materials Substrate modulation Catalyst Catalytic mechanism
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Nanosized Anatase TiO_(2) with Exposed(001)Facet for High-Capacity Mg^(2+)Ion Storage in Magnesium Ion Batteries
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作者 Rong Li Liuyan Xia +6 位作者 Jili Yue Junhan Wu Xuxi Teng Jun Chen Guangsheng Huang Jingfeng Wang Fusheng Pan 《Nano-Micro Letters》 2026年第1期438-457,共20页
Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosize... Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosized anatase TiO_(2) exposed(001)facet doubles the capacity compared to the micro-sized sample ascribed to the interfacial Mg^(2+)ion storage.First-principles calculations reveal that the diffusion energy barrier of Mg^(2+)on the(001)facet is significantly lower than those in the bulk phase and on(100)facet,and the adsorption energy of Mg^(2+)on the(001)facet is also considerably lower than that on(100)facet,which guarantees superior interfacial Mg^(2+)storage of(001)facet.Moreover,anatase TiO_(2) exposed(001)facet displays a significantly higher capacity of 312.9 mAh g^(−1) in Mg-Li dual-salt electrolyte compared to 234.3 mAh g^(−1) in Li salt electrolyte.The adsorption energies of Mg^(2+)on(001)facet are much lower than the adsorption energies of Li+on(001)facet,implying that the Mg^(2+)ion interfacial storage is more favorable.These results highlight that controlling the crystal facet of the nanocrystals effectively enhances the interfacial storage of multivalent ions.This work offers valuable guidance for the rational design of high-capacity storage systems. 展开更多
关键词 Magnesium ion batteries High capacity nanosized anatase TiO_(2) Crystal facet Interfacial ion storage
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Performance analysis of nanostructured lipid carriers for chemical sunscreen agents
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作者 Xiaoyu Li Jianping Jiang Lifeng Xiao 《日用化学工业(中英文)》 北大核心 2025年第2期185-193,共9页
Nanolipid carriers and traditional emulsion containing chemical sunscreens were prepared using emulsification combined with ultrasonic technology.The nanolipid carriers showed superior performance in sunscreen encapsu... Nanolipid carriers and traditional emulsion containing chemical sunscreens were prepared using emulsification combined with ultrasonic technology.The nanolipid carriers showed superior performance in sunscreen encapsulation,slow release and skin impermeability,and provided an excellent nanolipid slow-release encapsulation system for sunscreens.As observed by transmission electron microscopy,the nanolipid carriers were spherical shape,with smooth surface and uniform distribution,and the particle sizes were mainly concentrated in the range of 230 to 250 nm without agglomeration.The nanolipid carriers significantly improved the sunscreen performance through the synergistic effect of scattering and chemical absorption,and showed better UV stability than traditional sunscreen,indicating their photoprotective function.In vitro release experiments showed that the nano-lipidic carriers exhibited better release control when loaded with octyl methoxycinnamate(OMC)and butylmethoxydibenzoylmethane(BDFM)sunscreens than traditional traditional emulsions,with the cumulative release rate of OMC in the nano-lipidic carriers decreasing by 17.17% to 30.24% within 12 hours,and that of BDFM decreasing by 26.67% to 44.67%.26.67% to 44.16%.The results of the in vitro permeation experiment further confirmed that the nanolipid carriers could effectively encapsulate the sunscreens and prevent them from penetrating the skin barrier,thus reducing the skin irritation.Compared with traditional traditional emulsion,the cumulative penetration of OMC in nanostructured lipid carriers was 2.24μg/cm^(2)in 4 hours,while the cumulative penetration was reduced by 68.05%.The cumulative penetration of BDFM in the nanostructured lipid carrier was 3.24μg/cm^(2),with a 64.04%reduction in cumulative penetration. 展开更多
关键词 nano lipid carrier sunscreen agents PHOTOSTABILITY in vitro sustained-release properties extracorporeal permeability
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Advanced Computational Modeling and Mechanical Behavior Analysis of Multi-Directional Functionally Graded Nanostructures:A Comprehensive Review
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作者 Akash Kumar Gartia S.Chakraverty 《Computer Modeling in Engineering & Sciences》 2025年第3期2405-2455,共51页
This review explores multi-directional functionally graded(MDFG)nanostructures,focusing on their material characteristics,modeling approaches,and mechanical behavior.It starts by classifying different types of functio... This review explores multi-directional functionally graded(MDFG)nanostructures,focusing on their material characteristics,modeling approaches,and mechanical behavior.It starts by classifying different types of functionally graded(FG)materials such as conventional,axial,bi-directional,and tri-directional,and the material distribution models like power-law,exponential,trigonometric,polynomial functions,etc.It also discusses the application of advanced size-dependent theories like Eringen’s nonlocal elasticity,nonlocal strain gradient,modified couple stress,and consistent couple stress theories,which are essential to predict the behavior of structures at small scales.The review covers the mechanical analysis of MDFG nanostructures in nanobeams,nanopipes,nanoplates,and nanoshells and their dynamic and static responses under different loading conditions.The effect of multi-directional material gradation on stiffness,stability and vibration is discussed.Moreover,the review highlights the need for more advanced analytical,semi-analytical,and numerical methods to solve the complex vibration problems ofMDFG nanostructures.It is evident that the continued development of these methods is crucial for the design,optimization,and real-world application of MDFG nanostructures in advanced engineering fields like aerospace,biomedicine,and micro/nanoelectromechanical systems(MEMS/NEMS).This study is a reference for researchers and engineers working in the domain of MDFG nanostructures. 展开更多
关键词 Functionally graded multi-directional nano SIZE-DEPENDENT VIBRATION
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Micro-amplitude vibration-assisted scratching:a new method for one step and controllable fabrication of the microscale V-groove and nanoscale ripples
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作者 Haoxiang Wu Hu Huang +1 位作者 Zhiyu Zhang Jiwang Yan 《International Journal of Extreme Manufacturing》 2025年第3期398-421,共24页
Micro/nano hierarchical structures could endow materials with various surface functions.However,the multilayer and multiscale characteristics of micro/nano hierarchical structures bring difficulties for their one step... Micro/nano hierarchical structures could endow materials with various surface functions.However,the multilayer and multiscale characteristics of micro/nano hierarchical structures bring difficulties for their one step and controllable fabrication.Accordingly,based on tip-based fabrication techniques,this study proposed a micro-amplitude vibration-assisted scratching method by introducing a periodic backward displacement into the conventional scratching process,which enabled the synchronous creation of the microscale V-groove and nanoscale ripples,i.e.a typical micro/nano hierarchical structure.The experiments and finite element modeling were employed to explore the formation process and mechanism of the micro/nano hierarchical structures.Being different from conventional cutting,this method was mainly based on the plow mechanism,and it could accurately replicate the shape of the indenter on the material surface.The microscale V-groove was formed due to the scratching action,and the nanoscale ripple was formed due to the extrusion action of the indenter on the microscale V-groove’s surface.Furthermore,the relationships between the processing parameters and the dimensions of the micro/nano hierarchical structures were established through experiments,and optimized processing parameters were determined to achieve regular micro/nano hierarchical structures.By this method,complex patterns constructed by various micro/nano hierarchical structures were fabricated on both flat and curved surfaces,achieving diverse surface structural colors. 展开更多
关键词 vibration-assisted scratching tip-based micro/nano fabrication micro/nano hierarchical structure structural color
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Electrospun photothermal tellurium nanosheet-loaded polycaprolactone/gelatin nanofibers to promote wound healing
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作者 Fangjia Li Jing Zhang +2 位作者 Huan Xiong Lihua Min Li Gou 《Journal of Innovative Optical Health Sciences》 2025年第4期191-204,共14页
Low-cost and biodegradable photothermal wound dressings with remarkable therapeutic effects are highly desirable for next-generation wound healing.Herein,we report an efficient photothermal wound dressing mat made of ... Low-cost and biodegradable photothermal wound dressings with remarkable therapeutic effects are highly desirable for next-generation wound healing.Herein,we report an efficient photothermal wound dressing mat made of tellurium nanosheet(TeNS)-loaded electrospun polycaprolactone/gelatin(PCL/GEL)nanofibers.The TeNS-loaded PCL/GEL nanofibrous architectures showed antibacterial efficacy against Escherichia coli and Staphylococcus aureus of 87.68%and 94.57%,respectively.Under near-infrared+(NIR)light illumination,they can facilitate cell proliferation as revealed by in vitro scratch assay.The results from in vivo skin wounds combined with tissue staining experiments further showed that the TeNS-loaded dressing could substantially promote wound healing under photothermal conditions.Using immunohistochemical analysis,we found that the TeNS-loaded PCL/GEL nanofibers NIR group have a high expression of specific antigens in epidermal growth factor(EGF)(P<0.001)and endothelial cell adhesion molecule-31(CD31,P<0.05),verifying that the nanofibrous mat can stimulate EGF generation and microvessel proliferation.Furthermore,the PCL/GEL/TeNIR group has the lowest expression in endothelial cell adhesion molecule-68(CD68,P<0.001),suggesting that the nanofibrous mats have a high anti-inflammatory efficiency.Our work sheds light on the development of novel nonanti-inflammatory wound dressings via photothermal sterilization and the promotion of cell growth using two-dimensional(2D)nanosheets. 展开更多
关键词 TELLURIUM electrospin nano¯ber photothermal effect wound healing
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Preface to the Special Issue on “Experimental Mechanics at the Micro/Nanoscale”
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作者 Xide Li Wei Qiu +1 位作者 Dabiao Liu Mengxiong Liu 《Acta Mechanica Solida Sinica》 2025年第2期181-182,共2页
Over the past three decades,micro/nano science and technology have experienced rapid advancements as new materials and advanced devices have increasingly evolved towards high levels of integration and miniaturization.... Over the past three decades,micro/nano science and technology have experienced rapid advancements as new materials and advanced devices have increasingly evolved towards high levels of integration and miniaturization.In this context,mechanical properties have emerged as critical parameters for evaluating the operational performance and longevity of materials and devices at the micro/nanoscale. 展开更多
关键词 operational performance MINIATURIZATION DEVICES integration mechanical properties LONGEVITY micro nano science technology advanced devices
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Efficient U(VI) removal by Ti_(3)C_(2)T_(x) nanosheets modified with sulfidated nano zero-valent iron: Batch experiments, mechanism, and biotoxicity assessment
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作者 Liping Liang Mengfan Zhou +8 位作者 Fenfen Xi Chaoqi Bai Shenghua Wang Shuyun Luo Jingqi Liu Yangyang Hu Yuxuan Zeng Wangliang Yang Baowei Hu 《Journal of Environmental Sciences》 2025年第6期563-576,共14页
The MXenes,a new class of two-dimensional layered materials,have found extensive applications in water treatment for its excellent thermal stability,electrical conductivity,and excellent adsorption ability.Sulfidized ... The MXenes,a new class of two-dimensional layered materials,have found extensive applications in water treatment for its excellent thermal stability,electrical conductivity,and excellent adsorption ability.Sulfidized nano zero-valent iron(S-nZVI)is a good reducing agent,however,the practical application of S-nZVI is currently restricted due to the tendency of nano materials to agglomerate.Herein,MXenes use as a support and in situ loading S-nZVI on it to prepare a new material(S-nZVI/Ti_(3)C_(2)T_(x)),and applied it to U(VI)removal in water treatment.The microscopic characterization proves that S-nZVI on Ti_(3)C_(2)T_(x) has good dispersion and effectively alleviates agglomeration.Batch experiments shown that SnZVI/Ti_(3)C_(2)T_(x) has a very good effect on U(VI)removal,and themaximumadsorption capacity reaches 674.4mg/g under the aerobic condition at pH=6.0.The pseudo-second-order kinetic model and the Langmuir isotherm model were found to be more appropriate for describing the adsorption behavior.This indicates that the removal process is a single molecular layer chemisorption.Moreover,the S-nZVI/Ti_(3)C_(2)T_(x) maintained a removal efficiency of over 85%for U(VI)even after being reused five times,demonstrating its excellent reusability.It is worth noting that the material can remove 79.8%of 50 mg/L of U(VI)in simulated seawater,indicating that S-nZVI/Ti_(3)C_(2)T_(x) possessed an excellent uranium extraction performance from seawater.Experimental results and XPS analysis showed that U(VI)was removed by adsorption,reduction and co-precipitation.Moreover,S-nZVI/Ti_(3)C_(2)T_(x) was a lowtoxicitymaterial to Hyriopsis cumingii.Therefore,S-nZVI/Ti_(3)C_(2)T_(x) was expected to be a candidate as adsorbent with great potential in removal of uranium from wastewater and seawater. 展开更多
关键词 Sulfidated nano zero-valent iron Ti_(3)C_(2)T_(x) U(VI) ADSORPTION Reduction Biological toxicity
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Designing catalysts to formic acid oxidation reaction:From nanoscale to single atoms
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作者 GONG Jia-xin HU Shou-yao XIONG Yu 《Journal of Central South University》 CSCD 2024年第12期4586-4600,共15页
Formic acid oxidation reaction(FAOR),as the anodic reaction in direct formic acid fuel cells,has attracted much attention but increasing the mass activity and stability of catalysts still face a bottleneck to meet the... Formic acid oxidation reaction(FAOR),as the anodic reaction in direct formic acid fuel cells,has attracted much attention but increasing the mass activity and stability of catalysts still face a bottleneck to meet the requirements of practical applications.In the past decades,researchers developed many strategies to fix these issues by improving the structure of catalysts and the newly raised single atom catalysts(SACs)show the high mass activity and stability in FAOR.This review first summarized the reaction mechanism involved in FAOR.The mass activity as well as stability of catalysts reported in the past five years have been outlined.Moreover,the synthetic strategies to improve the catalytic performance of catalysts are also reviewed in this work.Finally,we proposed the research directions to guide the rational design of new FAOR catalysts in the future. 展开更多
关键词 formic acid oxidation reaction nanosized catalysts single atom catalysts synthetic strategy
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Nanos3与生殖细胞发育分化 被引量:3
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作者 于萌 廉智敏 华进联 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2012年第4期326-331,共6页
小鼠Nanos3基因是果蝇Nanos的同源基因,是Nanos基因家族的一员.Nanos3是一种RNA结合蛋白,靠近其C端有两个非常保守且连续的Cys-Cys-His-Cys特异锌指结构域.研究显示,Nanos3在小鼠生殖细胞中特异表达,不仅在原始生殖细胞(primordial germ... 小鼠Nanos3基因是果蝇Nanos的同源基因,是Nanos基因家族的一员.Nanos3是一种RNA结合蛋白,靠近其C端有两个非常保守且连续的Cys-Cys-His-Cys特异锌指结构域.研究显示,Nanos3在小鼠生殖细胞中特异表达,不仅在原始生殖细胞(primordial germ cells,PGCs)的维持方面发挥重要作用,而且是一种启动雄性生殖细胞分化程序的内源性因子,其在精子发生中的重要作用已引起越来越多的关注.探讨Nanos3的生物学功能,有助于了解生殖细胞发育过程中的部分重要机制.本文就Nanos3维持生殖细胞更新和原始生殖细胞的维持等作用作一综述. 展开更多
关键词 nanos3 nanos基因家族 自我更新 生殖细胞
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Recent advances in zwitterionic nanoscale drug delivery systems to overcome biological barriers 被引量:1
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作者 Xumei Ouyang Yu Liu +2 位作者 Ke Zheng Zhiqing Pang Shaojun Peng 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2024年第1期49-68,共20页
Nanoscale drug delivery systems(nDDS)have been employed widely in enhancing the therapeutic efficacy of drugs against diseases with reduced side effects.Although several nDDS have been successfully approved for clinic... Nanoscale drug delivery systems(nDDS)have been employed widely in enhancing the therapeutic efficacy of drugs against diseases with reduced side effects.Although several nDDS have been successfully approved for clinical use up to now,biological barriers between the administration site and the target site hinder the wider clinical adoption of nDDS in disease treatment.Polyethylene glycol(PEG)-modification(or PEGylation)has been regarded as the gold standard for stabilising nDDS in complex biological environment.However,the accelerated blood clearance(ABC)of PEGylated nDDS after repeated injections becomes great challenges for their clinical applications.Zwitterionic polymer,a novel family of antifouling materials,have evolved as an alternative to PEG due to their super-hydrophilicity and biocompatibility.Zwitterionic nDDS could avoid the generation of ABC phenomenon and exhibit longer blood circulation time than the PEGylated analogues.More impressively,zwitterionic nDDS have recently been shown to overcome multiple biological barriers such as nonspecific organ distribution,pressure gradients,impermeable cell membranes and lysosomal degradation without the need of any complex chemical modifications.The realization of overcoming multiple biological barriers by zwitterionic nDDS may simplify the current overly complex design of nDDS,which could facilitate their better clinical translation.Herein,we summarise the recent progress of zwitterionic nDDS at overcoming various biological barriers and analyse their underlyingmechanisms.Finally,prospects and challenges are introduced to guide the rational design of zwitterionic nDDS for disease treatment. 展开更多
关键词 Zwitterionic polymer Nano drug delivery system Biological barrier Targeting delivery Disease treatment
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河南华溪蟹nanos1、nanos2、piwi基因部分序列的克隆及表达特征 被引量:1
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作者 刘俊卿 孙敏 王兰 《淡水渔业》 CSCD 北大核心 2020年第5期10-16,共7页
为获取河南华溪蟹(Sinopotamon henanense)nanos1、nanos2和piwi基因的表达特征,在前期河南华溪蟹卵巢组织转录组测序的基础上,对生殖相关基因nanos1、nanos2和piwi进行了克隆和分析,首次获得了河南华溪蟹nanos1、nanos2和piwi基因的部... 为获取河南华溪蟹(Sinopotamon henanense)nanos1、nanos2和piwi基因的表达特征,在前期河南华溪蟹卵巢组织转录组测序的基础上,对生殖相关基因nanos1、nanos2和piwi进行了克隆和分析,首次获得了河南华溪蟹nanos1、nanos2和piwi基因的部分cDNA序列。利用半定量PCR获取了河南华溪蟹nanos1、nanos2和piwi基因的组织表达谱特征和在卵巢发育过程中的表达变化规律。研究结果显示,nanos1基因在卵巢、精巢、鳃、心和肌肉中均有表达;nanos2基因在卵巢、精巢、副性腺、心脏、肠和肌肉中有较高表达,且卵巢中表达量高于精巢中表达量;piwi基因特异表达于卵巢和精巢。卵巢发育中3个基因的表达时序研究显示,nanos1基因从卵巢发育的增殖期、小生长期、大生长期到成熟期表达量逐渐升高,与之相反,nanos2和piwi基因的表达呈现相反的趋势。这些研究结果将为河南华溪蟹nanos1、nanos2和piwi基因的功能分析奠定基础。 展开更多
关键词 河南华溪蟹(Sinopotamon henanense) nanos1 nanos2 PIWI 克隆 表达特征
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nanos同源基因在黑脊倒刺鲃生殖细胞中的表达研究 被引量:4
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作者 苏敏 陈元仲 +1 位作者 吕博彦 唐良华 《生物技术》 CAS CSCD 北大核心 2012年第4期28-32,共5页
目的:研究黑脊倒刺鲃scnanos的核苷酸序列及其在配子发生中的空间表达特征,以期为鱼类生殖发育研究提供一个有效的分子标记。方法:RT-PCR法首次克隆出scnanos基因,并检测其在不同组织中的表达水平,进而原位杂交法检测其在性腺中的表达... 目的:研究黑脊倒刺鲃scnanos的核苷酸序列及其在配子发生中的空间表达特征,以期为鱼类生殖发育研究提供一个有效的分子标记。方法:RT-PCR法首次克隆出scnanos基因,并检测其在不同组织中的表达水平,进而原位杂交法检测其在性腺中的表达水平。结果:scnanos开放阅读框长456bp,编码152个氨基酸。其具有较高的保守性,与鲤鱼、斑马鱼、家蚕、大熊猫、紫色球海胆的相似性分别为81%、63%、52%、50%、44%;scnanos仅在性腺表达,精子发生中,scnanos仅在精原细胞和精母细胞中表达。卵子发生的各时期都发现有scnanos的表达,且杂交信号的强度都随着配子发生的进行逐渐减弱。结论:该研究得到的scnanos是斑马鱼nanos的同源基因,而且此基因适合作为黑脊倒刺鲃及其它鱼类生殖发育研究的有效分子标记基因。 展开更多
关键词 黑脊倒刺鲃 nanos 原位杂交 生殖细胞
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日本血吸虫新基因Sjnanos的克隆、表达及免疫保护效果评估 被引量:2
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作者 王艳 郭凡吉 +6 位作者 彭金彪 李晔 洪炀 陈实 傅志强 石耀军 林矫矫 《中国人兽共患病学报》 CAS CSCD 北大核心 2010年第7期631-637,共7页
目的扩增、表达日本血吸虫Sjnanos编码基因并评估其重组蛋白诱导的免疫保护效果。方法从42d龄的日本血吸虫成虫中扩增了一个日本血吸虫性别差异表达的基因,GenBank登录号为AY814948,并对其进行生物信息学分析。将该基因亚克隆入原核表... 目的扩增、表达日本血吸虫Sjnanos编码基因并评估其重组蛋白诱导的免疫保护效果。方法从42d龄的日本血吸虫成虫中扩增了一个日本血吸虫性别差异表达的基因,GenBank登录号为AY814948,并对其进行生物信息学分析。将该基因亚克隆入原核表达载体pET28a,转化至大肠埃希菌(E.coli)BL21,用异丙基-β-D硫代半乳糖苷(IPTG)进行诱导表达,用纯化的重组蛋白免疫小鼠,ELISA检测其血清特异性抗体效价,蛋白印迹分析检测其抗原性,以看家基因NADH为内参,应用荧光定量PCR技术分析该基因在血吸虫各个阶段的表达状况。结果同源性分析表明,该基因为日本血吸虫的一个新基因,其编码序列的开放阅读框(ORF)为525bp,编码174个氨基酸,理论相对分子量为19.9,PI为8.2。荧光定量PCR技术分析显示该基因在7d、13d、18d、23d、32d、42d虫体均有表达,但在18d和13d虫体的表达量明显高于其他天数的虫体,在雄虫的表达量高于雌虫。成功构建了该基因的重组表达质粒pET28a(+)-Sjnanos,并在大肠埃希菌中获得表达,Western-blot分析表明重组蛋白具有较好的免疫原性,动物免疫保护试验获得了31.4%的减虫率和53.8%的肝脏减卵率。结论获得日本血吸虫新的抗原基因Sjnanos,该基因的重组蛋白在小鼠中诱导了部分免疫保护作用。 展开更多
关键词 日本血吸虫 nanos基因 抗原性 免疫保护
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nanos基因的研究进展 被引量:1
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作者 张春冬 潘敏慧 +3 位作者 李娜 孙志亚 谈娟 鲁成 《细胞生物学杂志》 CSCD 2009年第1期58-62,共5页
nanos基因在时空上的表达调控对于个体发育起着重要作用。母源nanos mRNA在卵子中的定位及翻译调控受到严格的控制。果蝇Nanos通过抑制后极hunchback mRNA的翻译建立胚胎后极信号中心,从而建立前后体轴;同时它对果蝇原始生殖细胞的决定... nanos基因在时空上的表达调控对于个体发育起着重要作用。母源nanos mRNA在卵子中的定位及翻译调控受到严格的控制。果蝇Nanos通过抑制后极hunchback mRNA的翻译建立胚胎后极信号中心,从而建立前后体轴;同时它对果蝇原始生殖细胞的决定及迁移有重要作用;Nanos对于胚后发育中生殖细胞的维持也是必须的。现对nanos基因的mRNA的定位、翻译调控及Nanos结构和功能的研究进展进行了综述。 展开更多
关键词 nanos 原始生殖细胞 早期胚胎发育
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汽车传动部件用40Cr钢表面Ni-nanoSiC复合镀层的制备 被引量:1
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作者 王斌 《兵器材料科学与工程》 CAS CSCD 北大核心 2017年第5期86-90,共5页
采用电沉积方法在汽车传动部件用40Cr钢表面制备Ni-nanoSiC复合镀层。以复合镀层中SiC质量分数和复合镀层的硬度作为指标,通过正交实验优化施镀工艺参数,得到最佳施镀工艺参数:搅拌速度为300 r/min、镀液中SiC颗粒质量浓度为20 g/L、温... 采用电沉积方法在汽车传动部件用40Cr钢表面制备Ni-nanoSiC复合镀层。以复合镀层中SiC质量分数和复合镀层的硬度作为指标,通过正交实验优化施镀工艺参数,得到最佳施镀工艺参数:搅拌速度为300 r/min、镀液中SiC颗粒质量浓度为20 g/L、温度为50℃、阴极电流密度为14 A/dm2。结果表明:采用最佳施镀工艺参数制备的Ni-SiC复合镀层表面平整、组织致密,其磨损机制为轻度磨粒磨损,平均摩擦因数约为0.45,低于40Cr钢的0.6;磨损量约为6.27 mg,相比40Cr钢约降低25.6%。Ni-nanoSiC复合镀层能够提供有效的防护,改善和提高40Cr钢的抗磨损性能。 展开更多
关键词 Ni-nanosiC复合镀层 40CR钢 汽车传动部件 硬度 磨损量 形貌
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细粒棘球绦虫nanos基因的分子克隆及序列分析
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作者 叶倩 马勋 +2 位作者 薄新文 王正荣 张艳艳 《黑龙江畜牧兽医》 CAS 北大核心 2015年第4期32-34,38,246,共5页
为了研究细粒棘球绦虫nanos基因的序列及结构并为疫苗及新的药物研制提供靶标,试验采用注释并克隆细粒棘球绦虫nanos基因的方法,并对其序列结构进行分析;利用在线生物信息学软件分析细粒棘球绦虫nanos基因的序列结构及与其他虫属的进化... 为了研究细粒棘球绦虫nanos基因的序列及结构并为疫苗及新的药物研制提供靶标,试验采用注释并克隆细粒棘球绦虫nanos基因的方法,并对其序列结构进行分析;利用在线生物信息学软件分析细粒棘球绦虫nanos基因的序列结构及与其他虫属的进化关系。结果表明:细粒棘球绦虫nanos基因ORF为687 bp,编码228个氨基酸,理论分子质量为58 090.6 u,等电位点为5.08;细粒棘球绦虫NANOS蛋白由3个α螺旋和4个β片层组成;发现共有1个丝氨酸位点,1个苏氨酸位点,2个酪氨酸位点,可能的磷酸化位点是7,8,13,18,19,23位。说明该基因可能在细粒棘球绦虫生殖细胞发育过程中发挥着重要作用。 展开更多
关键词 细粒棘球绦虫 nanos基因 氨基酸 磷酸化位点 生殖细胞
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Hydrothermal synthesis of nanosized ZSM-22 and their use in the catalytic conversion of methanol 被引量:4
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作者 陈磊 卢鹏 +3 位作者 袁扬扬 徐力 张晓敏 许磊 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1381-1388,共8页
ZSM‐22 zeolite with different crystal lengths was prepared using a modified hydrothermal method. Rotation speed, Si/Al molar ratio and co‐solvent have important effects on the crystal size of ZSM‐22. The nanosized ... ZSM‐22 zeolite with different crystal lengths was prepared using a modified hydrothermal method. Rotation speed, Si/Al molar ratio and co‐solvent have important effects on the crystal size of ZSM‐22. The nanosized zeolite samples were characterized by X‐ray diffraction, X‐ray fluorescence, nitrogen adsorption, scanning electron microscopy, temperature‐programmed desorption of am‐monia and solid state nuclear magnetic resonance. The catalytic performance of nanosized ZSM‐22 was tested using the conversion of methanol. Compared to conventional ZSM‐22, the nanosized ZSM‐22 zeolite exhibited superior selectivity to ethylene and aromatics and lower selectivity to propylene. Stability against deactivation was clearly shown by the nanosized ZSM‐22 zeolite. A higher external surface area and smaller particle size make this nanosized ZSM‐22 zeolite attractive for catalytic applications. 展开更多
关键词 nanosized ZSM-22 zeolite Hydrothermal synthesis Conversion of methanol
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