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Epigenetic integrity of paternal imprints enhances the developmental potential of androgenetic haploid embryonic stem cells 被引量:2
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作者 Hongling Zhang Yuanyuan Li +4 位作者 Yongjian Ma Chongping Lai Qian Yu Guangyong Shi Jinsong Li 《Protein & Cell》 SCIE CSCD 2022年第2期102-119,共18页
The use of two inhibitors of Mek1/2 and Gsk3β(2i)promotes the generation of mouse diploid and haploid embryonic stem cells(ESCs)from the inner cell mass of biparental and uniparental blastocysts,respectively.However,... The use of two inhibitors of Mek1/2 and Gsk3β(2i)promotes the generation of mouse diploid and haploid embryonic stem cells(ESCs)from the inner cell mass of biparental and uniparental blastocysts,respectively.However,a system enabling long-term maintenance of imprints in ESCs has proven challenging.Here,we report that the use of a two-step a2i(alternative two inhibitors of Src and Gsk3β,TSa2i)derivation/culture protocol results in the establishment of androgenetic haploid ESCs(AG-haESCs)with stable DNA methylation at paternal DMRs(differentially DNA methylated regions)up to passage 60 that can efficiently support generating mice upon oocyte injection.We also show coexistence of H3K9me3 marks and ZFP57 bindings with intact DMR methylations.Furthermore,we demonstrate that TSa2itreated AG-haESCs are a heterogeneous cell population regarding paternal DMR methylation.Strikingly,AGhaESCs with late passages display increased paternal-DMR methylations and improved developmental potential compared to early-passage cells,in part through the enhanced proliferation of H19-DMR hypermethylated cells.Together,we establish AG-haESCs that can longterm maintain paternal imprints. 展开更多
关键词 paternal imprints androgenetic haploid ESCs DMRs semi-cloned mice alternative 2i
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On the relationship between imprint and reliability in Hf_(0.5)Zr_(0.5)O_(2) based ferroelectric random access memory
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作者 Peng Yuan Yuting Chen +9 位作者 Liguo Chai Zhengying Jiao Qingjie Luan Yongqing Shen Ying Zhang Jibin Leng Xueli Ma Jinjuan Xiang Guilei Wang Chao Zhao 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期42-47,共6页
The detrimental effect of imprint,which can cause misreading problem,has hindered the application of ferroelectric HfO_(2).In this work,we present results of a comprehensive reliability evaluation of Hf_(0.5)Zr_(0.5)O... The detrimental effect of imprint,which can cause misreading problem,has hindered the application of ferroelectric HfO_(2).In this work,we present results of a comprehensive reliability evaluation of Hf_(0.5)Zr_(0.5)O_(2)-based ferroelectric random access memory.The influence of imprint on the retention and endurance is demonstrated.Furthermore,a solution in circuity is pro-posed to effectively solve the misreading problem caused by imprint. 展开更多
关键词 FERAM HZO IMPRINT RELIABILITY
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Imprinting at the KBTBD6 locus involves species-specific m ternal methylation and monoallelic expression in livestock animals
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作者 Jinsoo Ahn In-Sul Hwang +2 位作者 Mi-Ryung Park Seongsoo Hwang Kichoon Lee 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期127-145,共19页
Background The primary differentially methylated regions(DMRs) which are maternally hypermethylated serve as imprinting control regions(ICRs) that drive monoallelic gene expression, and these ICRs have been investigat... Background The primary differentially methylated regions(DMRs) which are maternally hypermethylated serve as imprinting control regions(ICRs) that drive monoallelic gene expression, and these ICRs have been investigated due to their implications in mammalian development. Although a subset of genes has been identified as imprinted, in-depth comparative approach needs to be developed for identification of species-specific imprinted genes. Here, we examined DNA methylation status and allelic expression at the KBTBD6 locus across species and tissues and explored potential mechanisms of imprinting.Results Using whole-genome bisulfite sequencing and RNA-sequencing on parthenogenetic and normal porcine embryos, we identified a maternally hypermethylated DMR between the embryos at the KBTBD6 promoter Cp G island and paternal monoallelic expression of KBTBD6. Also, in analyzed domesticated mammals but not in humans, non-human primates and mice, the KBTBD6 promoter Cp G islands were methylated in oocytes and/or allelically methyl-ated in tissues, and monoallelic KBTBD6 expression was observed, indicating livestock-specific imprinting. Further analysis revealed that these Cp G islands were embedded within transcripts in porcine and bovine oocytes which coexisted with an active transcription mark and DNA methylation, implying the presence of transcription-dependent imprinting.Conclusions In this study, our comparative approach revealed an imprinted expression of the KBTBD6 gene in domesticated mammals, but not in humans, non-human primates, and mice which implicates species-specific evolution of genomic imprinting. 展开更多
关键词 Differentially methylated region Domesticated mammal IMPRINTING KBTBD6 PARTHENOGENETIC
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A Transparent Photoresist Made of Titanium Dioxide Nanoparticle-Embedded Acrylic Resin with a Tunable Refractive Index for UV-Imprint Lithography
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作者 Yinglu Liu Dan Wang +7 位作者 Changlin Liu Qianqian Hao Jian Li Jie-Xin Wang Xiuyun Chen Peng Zhong Xibin Shao Jian-Feng Chen 《Engineering》 SCIE EI CAS CSCD 2024年第6期96-104,共9页
Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical fields.This work reports a kind of tunable optical material composed of ... Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical fields.This work reports a kind of tunable optical material composed of titanium dioxide nanoparticles embedded in acrylic resin with a high RI for ultraviolet(UV)-imprint lithography.The hybrid film exhibits a tunable RI of up to 1.67(589 nm)after being cured by UV light,while maintaining both a high transparency of over 98%in the visible light range and a low haze of less than 0.05%.The precision machining of optical microstructures can be imprinted easily and efficiently using the hybrid resin,which acts as a light guide plate(LGP)to guide the light from the side to the top in order to conserve the energy of the display device.These preliminary studies based on both laboratory and commercial experiments pave the way for exploiting the unparalleled optical properties of nanocomposite resins and promoting their industrial application. 展开更多
关键词 PHOTORESIST Tunable refractive index Hanson solubility Ultraviolet imprint Organic-inorganic composites
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Ionically Imprinting-Based Copper(Ⅱ)Label-Free Detection for Preventing Hearing Loss
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作者 Huan Wang Hui Zhang +3 位作者 Xiaoli Zhang Hong Chen Ling Lu Renjie Chai 《Engineering》 SCIE EI CAS CSCD 2024年第2期276-282,共7页
Copper is a microelement with important physiological functions in the body.However,the excess copper ion(Cu^(2+))may cause severe health problems,such as hair cell apoptosis and the resultant hearing loss.Therefore,t... Copper is a microelement with important physiological functions in the body.However,the excess copper ion(Cu^(2+))may cause severe health problems,such as hair cell apoptosis and the resultant hearing loss.Therefore,the assay of Cu^(2+)is important.We integrate ionic imprinting technology(IIT)and structurally colored hydrogel beads to prepare chitosan-based ionically imprinted hydrogel beads(IIHBs)as a low-cost and high-specificity platform for Cu^(2+)detection.The IIHBs have a macroporous microstructure,uniform size,vivid structural color,and magnetic responsiveness.When incubated in solution,IIHBs recognize Cu^(2+)and exhibit a reflective peak change,thereby achieving label-free detection.In addition,benefiting from the IIT,the IIHBs display good specificity and selectivity and have an imprinting factor of 19.14 at 100μmol·L^(-1).These features indicated that the developed IIHBs are promising candidates for Cu^(2+)detection,particularly for the prevention of hearing loss. 展开更多
关键词 Structural color Microfluidics Ionic imprinting Label-free detection Hearing loss
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MPI/OpenMP-Based Parallel Solver for Imprint Forming Simulation
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作者 Yang Li Jiangping Xu +2 位作者 Yun Liu Wen Zhong Fei Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期461-483,共23页
In this research,we present the pure open multi-processing(OpenMP),pure message passing interface(MPI),and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining pr... In this research,we present the pure open multi-processing(OpenMP),pure message passing interface(MPI),and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining process to address the challenge of capturing fine relief features of approximately 50 microns.Achieving such precision demands the utilization of at least 7 million tetrahedron elements,surpassing the capabilities of traditional serial programs previously developed.To mitigate data races when calculating internal forces,intermediate arrays are introduced within the OpenMP directive.This helps ensure proper synchronization and avoid conflicts during parallel execution.Additionally,in the MPI implementation,the coins are partitioned into the desired number of regions.This division allows for efficient distribution of computational tasks across multiple processes.Numerical simulation examples are conducted to compare the three solvers with serial programs,evaluating correctness,acceleration ratio,and parallel efficiency.The results reveal a relative error of approximately 0.3%in forming force among the parallel and serial solvers,while the predicted insufficient material zones align with experimental observations.Additionally,speedup ratio and parallel efficiency are assessed for the coining process simulation.The pureMPI parallel solver achieves a maximum acceleration of 9.5 on a single computer(utilizing 12 cores)and the hybrid solver exhibits a speedup ratio of 136 in a cluster(using 6 compute nodes and 12 cores per compute node),showing the strong scalability of the hybrid MPI/OpenMP programming model.This approach effectively meets the simulation requirements for commemorative coins with intricate relief patterns. 展开更多
关键词 Hybrid MPI/OpenMP parallel computing MPI OPENMP imprint forming
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Innovative Methods of Synthesis and Characterization for Molecularly Imprinted Polymers
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作者 Youyao Luo 《Open Journal of Applied Sciences》 2024年第9期2559-2579,共21页
The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are ove... The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are overlaps in the methods used by scholars. The Langmuir equation is frequently applied to model the adsorption isotherms of MIPs, providing critical insight into the capacity and affinity of the binding sites. Infrared Spectroscopy (IR) plays a crucial role in identifying the functional groups involved in the imprinting process and confirming the successful formation of specific binding sites. UV-visible spectrophotometry is employed to monitor the absorption characteristics of the polymers, offering data on the interactions between the template molecules and the polymer matrix. Transmission Electron Microscopy (TEM) provides detailed visualization of the internal structure of MIPs at the nanoscale, revealing the morphology and size of the imprinted cavities. Thermogravimetric Analysis (TGA) assesses the thermal stability and composition of the polymers, identifying decomposition patterns that are indicative of the material’s robustness under different conditions. Finally, the Laser Particle Size Analyzer is used to measure the size distribution of the polymer particles, which is critical for determining the uniformity and efficiency of the imprinting process. The six characterization methods discussed in this paper provide a comprehensive understanding of MIP, and it is hoped that in the future, more optimized design solutions will emerge and their applications in various fields will be enhanced. 展开更多
关键词 Molecularly Imprinted Polymers Langmuir Equation Infrared Spectroscopy UV Visible Spectrophotometry Transmission Electron Microscopy
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Ionic Liquid Assisted Imprint for Efficient and Stable Quasi-2D Perovskite Solar Cells with Controlled Phase Distribution 被引量:1
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作者 Haibin Peng Dengxue Li +4 位作者 Zongcai Li Zhi Xing Xiaotian Hu Ting Hu Yiwang Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第7期1-15,共15页
Although two-dimensional perovskite devices are highly stable,they also lead to a number of challenges.For instance,the introduction of large organic amines makes crystallization process complicated,causing problems s... Although two-dimensional perovskite devices are highly stable,they also lead to a number of challenges.For instance,the introduction of large organic amines makes crystallization process complicated,causing problems such as generally small grain size and blocked charge transfer.In this work,imprint assisted with methylamine acetate were used to improve the morphology of the film,optimize the internal phase distribution,and enhance the charge transfer of the perovskite film.Specifically,imprint promoted the dispersion of spacer cations in the recrystallization process with the assistance of methylamine acetate,thus inhibited the formation of low-n phase induced by the aggregation of spacer cations and facilitated the formation of 3D-like phase.In this case,the corresponding quasi-2D perovskite solar cells delivered improved efficiency and exhibited superior stability.Our work provides an effective strategy to obtain uniform phase distribution for quasi-2D perovskite. 展开更多
关键词 IMPRINT Two-dimensional perovskite Phase distribution Charge transfer Stability
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Synthesis,characterization,and performance comparison of boron using adsorbents based on N-methyl-D-glucosamine
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作者 Hui Jiang Zijian Zhao +4 位作者 Ning Yu Yi Qin Zhengwei Luo Wenhua Geng Jianliang Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期16-31,共16页
Using N-methyl-D-glucosamine(NMDG)as the functional monomer,glycidyl methacrylate(GMA)as the connecting monomer,functionalized Fe3O4 nano-particles(NPs)as the support,three adsorbents were prepared including direct po... Using N-methyl-D-glucosamine(NMDG)as the functional monomer,glycidyl methacrylate(GMA)as the connecting monomer,functionalized Fe3O4 nano-particles(NPs)as the support,three adsorbents were prepared including direct polymer GMA-NMDG,magnetic GMA-NMDG polymer(MGN),and boron magnetic ion-imprinted polymer(BMIIP).Based upon the optimization of synthesis conditions,the prepared adsorbents and intermediate products were characterized using Fourier transform infrared spectroscopy,thermogravimetric analysis,scanning electron microscope,energy dispersive spectroscopy,X-ray diffraction,vibrating sample magnetometer,and Brunauer–Emmett–Teller to investigate the synthesis process,the morphological structure and the functional properties of the materials.The optimum performances of GMA-NMDG,MGN and BMIIP were obtained in the initial neutral solution(pH of 6.5).Moreover,GMANMDG and MGN reached the maximum adsorption capacity at 120 min,whereas BMIIP reached adsorption saturation at 60 min.The pseudo-second-order kinetic model was more suitable for the adsorption of boron using the adsorbents.The maximum adsorption capacity of GMA-NMDG was found to be 43.4 mg·g^(-1),while those of MGN and BMIIP were 32.5 and 28.3 mg·g^(-1),respectively.The Langmuir isotherm model was more appropriate to describe the adsorption process.The adsorbents maintained satisfactory adsorption performance within a certain temperature range.Competing ions had little effect on the adsorption of boron,and would be adsorbed simultaneously,due to which,the effect of co-adsorption can be considered.The adsorption capacity of GMA-NMDG was high,while the adsorption selectivity of BMIIP was much better.Furthermore,BMIIP showed good adsorption after five cycles of adsorption and desorption.The comparison of adsorbents showed that GMA-NMDG had the highest adsorption capacity and was suitable for co-adsorption.MGN had a high adsorption capacity,good comprehensive performance and magnetic properties.BMIIP had better adsorption rate,adsorption selectivity and recyclability.Through the optimization of synthesis conditions,the adsorption capacity of the traditional monomer NMDG polymer was increased,and the magnetism was given to facilitate rapid recovery.Combined with the ion imprinting technology,it showed higher boron adsorption selectivity in the presence of competitive ions. 展开更多
关键词 BORON CARBOHYDRATE ADSORPTION Magnetic Surface imprinting CARRIER
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Preparation of bowl-shaped polydopamine surface imprinted polymer composite adsorbent for specific separation of 2'-deoxyadenosine
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作者 Pan Wang Mengdei Zhou +4 位作者 Zhuangxin Wei Lu Liu Tao Cheng Xiaohua Tian Jianming Pan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第8期69-79,共11页
Molecularly imprinted polymers (MIPs) have great potential as adsorbents for selective adsorption and separation of nucleoside compounds,but effectively enhancing the affinity of recognition sites by adjusting the for... Molecularly imprinted polymers (MIPs) have great potential as adsorbents for selective adsorption and separation of nucleoside compounds,but effectively enhancing the affinity of recognition sites by adjusting the forces between template molecules and functional monomers remains an important challenge.In this work,a surface imprinting strategy was used to construct bowl-shaped molecularly imprinted composite sorbents (BHPN@MIPs) based on polydopamine (PDA) particles and have achieved selective separation and purification of 2'-deoxyadenosine (dA).Where by the base complementary pairing interaction of the combined template molecule d A and the pyrimidine functional monomer can enhance the preassembly force,and the hydrophilic bowl-shaped PDA can provide a larger storage space contact efficiency of d A in the test solution,causing the site utilization much higher and improving the kinetic adsorption performance.The equilibrium adsorption time and maximum adsorption capacity of60 min and 328.45μmol·g^(-1)were observed by static adsorption experiments,and the selectivity experimental results showed an imprinting factor IF of 1.30.After four adsorption–desorption cycles,the initial adsorption equilibrium adsorption capacity of BHPN@MIPs still retained 91.14%.By evaluating the selective adsorption of d A in spiked human serum solutions,BHPN@MIPs can be used to selectively enrich and analyze target d A in complex biological samples. 展开更多
关键词 Molecularly imprinted polymers(MIPs) Bowl-shaped Base complementary pairing interaction Selective separation 2'-deoxyadenosine(dA)
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Adsorption of Cr(VI) by modified chitosan from heavy-metal polluted water of Xiangjiang River, China 被引量:14
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作者 刘韵琴 刘云国 +1 位作者 胡新将 郭一明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期3095-3103,共9页
Methacrylic acid was used together with a molecular imprinting technique to modify chitosan. In addition, the adsorption kinetics and adsorption isotherms were recorded and the results were analyzed to investigate rep... Methacrylic acid was used together with a molecular imprinting technique to modify chitosan. In addition, the adsorption kinetics and adsorption isotherms were recorded and the results were analyzed to investigate reparative adsorption for Cr(VI) from the polluted Xiangjiang River water. A comparative X-ray analysis shows that the degree of crystallization in the imprinted polymer was significantly weakened, the area of the non-crystalline region was larger. There were more adsorption sites in the imprinted polymer, and the adsorption capacity towards Cr(VI) was increased. The adsorption capacity of the imprinted polymer towards Cr(VI) increased with time and reaches saturation after 8 h. The optimal adsorption time was 4-8 h after the adsorption starting and the optimal pH value for the solution was in the range of 4.5-7.5. When the chitosan reaches saturation, the adsorption capacity achieves a state of equilibrium, and the maximum Cr(VI) extraction rate reaches 33.7%. Moreover, the adsorption capacity of the imprinted polymer towards Cr(VI) increases with increasing chitosan concentration. In this situation, the Cr(VI) extraction rate shows little variation, and the maximum removal rate can reach 98.3%. Furthermore, the Cr(VI) extraction rate increases with an increase in the degree of deacetylation in the chatoyant and chitosan, with the best adsorption effect corresponding to 90% deacetylation. Fitting the adsorption data to the quasi first- and second-order kinetic models yields correlation coefficients of 0.9013 and 0.9875, respectively. The corresponding rate constants for the two models are 0.0091 min-1 and 7.129 g/(mg.min), respectively. Hence, the adsorption using Cr(VI)-imprinted chitosan is more consistent with the second-order kinetics. Comparing the data to Freundlich and Langrnuir adsorption isotherms shows that the latter has a better linear fit and a maximum adsorption capacity of 15.784 mg/g. 展开更多
关键词 modified chitosan IMPRINTING heavy metal pollutants Cr(VI) ADSORPTION removal rate kinetic model
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食品中丙烯酰胺检测方法的研究进展 被引量:10
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作者 李娜 许翎婕 +1 位作者 李清明 郭时印 《食品研究与开发》 CAS 北大核心 2018年第9期213-219,共7页
丙烯酰胺是在食品高温加工过程中产生的小分子有机化合物,具有致癌性。从样品提取、衍生化、净化、富集等前处理过程以及对检测器的选择出发,总结国内外近年来用于检测丙烯酰胺的方法,如从传统的气相色谱、液相色谱及其联用技术,到新兴... 丙烯酰胺是在食品高温加工过程中产生的小分子有机化合物,具有致癌性。从样品提取、衍生化、净化、富集等前处理过程以及对检测器的选择出发,总结国内外近年来用于检测丙烯酰胺的方法,如从传统的气相色谱、液相色谱及其联用技术,到新兴开发的分子印迹技术、酶联免疫吸附和生物传感器等新检测技术。并根据其适用范围和操作条件,对各分析方法的优点和不足进行讲述,最后对将来丙烯酰胺检测方法发展新思路提供策略和依据。 展开更多
关键词 丙烯酰胺 检测技术 固相微萃取 分子印迹技术(molecular IMPRINTING technology MIT) 酶联免疫吸附法(enzyme-linked IMMUNOSORBENT assay ELISA)
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邻苯二甲酸二(2-丙基庚)酯分子印迹固相萃取剂的制备及其应用 被引量:3
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作者 韦寿莲 郭小君 +2 位作者 严子军 刘永 汪洪武 《色谱》 CAS CSCD 北大核心 2014年第5期458-463,共6页
以邻苯二甲酸二辛酯( DOP)为虚拟模板分子,α-甲基丙烯酸( MAA)为功能单体,乙二醇二甲基丙烯酸酯( EDMA)为交联剂,采用沉淀聚合法制备了对邻苯二甲酸二(2-丙基庚)酯( DPHP)具有高选择性的分子印迹聚合物( MIP)。用紫外... 以邻苯二甲酸二辛酯( DOP)为虚拟模板分子,α-甲基丙烯酸( MAA)为功能单体,乙二醇二甲基丙烯酸酯( EDMA)为交联剂,采用沉淀聚合法制备了对邻苯二甲酸二(2-丙基庚)酯( DPHP)具有高选择性的分子印迹聚合物( MIP)。用紫外分光光度法探索了不同功能单体与模板分子的结合能力,与功能单体丙烯酸( AA)相比,MAA 与DOP的结合能力更强,其最佳结合的物质的量比为6:1。考察 MIP 对 DOP、DPHP、邻苯二甲酸二甲酯( DMP)、邻苯二甲酸二丁酯( DBP)的选择吸附性能,发现该聚合物对 DPHP具有更高的选择吸附性。以制备的聚合物为固相萃取填料,结合 HPLC分析,考察了淋洗剂与洗脱剂的种类和用量对 DPHP 回收率的影响。将 DPHP 甲醇溶液加载至萃取柱后用1 mL甲醇-水(1:9,v/v)淋洗,5 mL甲醇-乙酸(9:1,v/v)洗脱,DPHP在分子印迹固相萃取( MI-SPE)柱上的回收率达到96.8%,而在非印迹固相萃取( NISPE)柱上的回收率仅为52.9%。将建立的 MISPE-HPLC方法应用于测定兔口服 DPHP后不同时间点兔血清中 DPHP的浓度,发现其血药浓度的最大值为5.88μg/mL,达峰值时间为4 h,DPHP加标回收率为90.0%~92.0%,相对标准偏差小于5%。 展开更多
关键词 虚拟模板 分子印迹聚合物 固相萃取 邻苯二甲酸二(2-丙基庚)酯 兔血清 molecular imprinted polymer( MIP ) SOLID-PHASE extraction (SPE) di(2-propylheptyl)phthalate(DPHP)
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Overexpression of IGF2R and IGF1R mRNA in SCNT-produced Goats Survived to Adulthood 被引量:1
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作者 邢宝松 徐银学 +2 位作者 成勇 刘红林 杜淼 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第8期709-719,共11页
The procedure of somatic cell nuclear transfer (SCNT) is likely to affect the expression level of growth-related genes especially imprinting genes. In this study, expressions of growth-related genes including three ... The procedure of somatic cell nuclear transfer (SCNT) is likely to affect the expression level of growth-related genes especially imprinting genes. In this study, expressions of growth-related genes including three imprinting genes (H19, IGF2, and IGF2R) and four non-imprinting genes (IGF1, IGFIR, GHR, and GHSR) in adult nuclear transferred (NT) goats were investigated by real-time PCR. The expressions of these genes in adult clones were found largely normal, but IGF2R and IGFIR were more highly expressed in cloned goats than in non-NT goats (P 〈 0.01). Analysis on mono-allelic expression pattern of imprinting genes indicated that mono-allelic expression patterns of H19 and IGF2 in cloned goats were similar to that in non-NT goats. In addition, the sequence of goat IGF2 gene and the putative amino acid sequence were obtained. The 986 nucleotide cDNA of goat IGF2 gene contained an open-reading frame of 540 nucleotides coding for 179 amino acids. Both cDNA sequence and amino acid sequence of IGF2 in goat showed their higher homology with that in sheep than in cattle; the partial cDNA fragments of H19, IGF2R, GHSR, IGFIR, and GHR in goat were also cloned and sequenced, which shared higher sequence identities with those in sheep than in cattle. 展开更多
关键词 GOAT nuclear transfer gene expression real-time PCR imprinting gene
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Molecular Genetic Diagnostics of Prader-Willi Syndrome:a Validation of Linkage Analysis for the Chinese Population 被引量:1
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作者 李洪义 孟舒 +8 位作者 陈争 李海飞 杜敏联 马华梅 魏海云 段红蕾 郑辉 闻人庆 宋新明 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第10期885-891,共7页
Prader-Willi Syndrome (PWS) is a genetic disorder that is difficult to detect, particularly at an early age. PWS is caused by disruption of normal, epigenetically controlled gene function in the chromosome 15q11-q13... Prader-Willi Syndrome (PWS) is a genetic disorder that is difficult to detect, particularly at an early age. PWS is caused by disruption of normal, epigenetically controlled gene function in the chromosome 15q11-q13 region. Clinical symptoms are difficult to diagnose in infants and only become clearer at later ages as the patients develop hyperphagia and morbid obesity. Molecular genetic tests are able to definitively diagnose PWS and allow early diagnosis of the syndrome. High resolution cytogenetic testing, methylation-specific PCR (MS-PCR), and linkage analysis are routinely used to diagnose PWS. To establish a linkage analysis method for Chinese patients, this study identified a useful set of STR markers in the typical PWS deletion and adjacent area, for linkage analysis in two Chinese families with PWS offspring. Using this method, the authors confn'rned that one patient had a paternal deletion in chromosome 15q 11-q 13 and the other patient had maternal uniparental heterodisomy of chromosome 15. MS -PCR and high resolution chromosome G-banding also confirmed this diagnosis. This linkage analysis method can detect both deletion and uniparental disomy, thus providing valuable information for genetic counseling and the opportunity to analyze the relationship between the genotype and phenotype of PWS. 展开更多
关键词 Prader-Willi Syndrome uniparental disomy OBESITY genomic imprinting linkage analysis
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Plant Genomic Imprinting and Its Effect on Seed Development 被引量:1
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作者 孙超 唐天向 +6 位作者 唐伟杰 隋丽波 张慧 夏张婷 赵海洋 韩月鑫 林良斌 《Agricultural Science & Technology》 CAS 2017年第6期984-987,1032,共5页
Genomic imprinting is the epigenetic phenomenon by which certain genes are expressed in a parent-of-origin-specific manner, and was first discovered in mammalian embryos. Recent studies have shown that it also occurs ... Genomic imprinting is the epigenetic phenomenon by which certain genes are expressed in a parent-of-origin-specific manner, and was first discovered in mammalian embryos. Recent studies have shown that it also occurs in developing plant seeds, and is now becoming a hot topic of biology of plant seed development. According to the previous studies on imprinted genes, imprinting mechanism and their roles in plant seed development, the current progress of genomic imprinting in plant seed development was summarized and possible strategies were proposed to deal with the problems, which could provide helpful information for further research. 展开更多
关键词 Plant seed Genomic imprinting EPIGENETICS
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铅模板交联壳聚糖聚合物的表征及吸附选择性研究 被引量:1
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作者 张名楠 于文辉 梁振益 《环境污染与防治》 CAS CSCD 北大核心 2014年第2期57-61,66,共6页
以Pb2+为模板分子,以壳聚糖(CTS)为功能单体合成了CTS-Pb2+复合物、CTS-Pb2+交联聚合物及Pb2+交联CTS分子印迹聚合物(MIP)。采用红外光谱仪、热重分析仪、扫描电镜、X衍射仪等仪器对CTS、CTS-Pb2+复合物、CTS-Pb2+交联聚合物和MIP的表... 以Pb2+为模板分子,以壳聚糖(CTS)为功能单体合成了CTS-Pb2+复合物、CTS-Pb2+交联聚合物及Pb2+交联CTS分子印迹聚合物(MIP)。采用红外光谱仪、热重分析仪、扫描电镜、X衍射仪等仪器对CTS、CTS-Pb2+复合物、CTS-Pb2+交联聚合物和MIP的表面形貌和结构进行了表征。结果表明,CTS吸附Pb2+是以—NH2为吸附点;CTS吸附Pb2+后,结晶度下降、热稳定性变差;利用分子印迹技术得到的MIP呈具有一定孔径分布的多孔结构,这有利于Pb2+的吸附和洗脱,也为Pb2+的扩散或洗脱提供了良好的通道;MIP在实际水样处理中体现出较高的Pb2+吸附选择性,它在处理含Pb2+废水方面可能具有较好的应用前景。 展开更多
关键词 交联壳聚糖 分子印迹聚合物 PB2+ 选择性 MOLECULAR imprinted POLYMER (MIP) PB2+
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Epigenetics and neural stem cell commitment 被引量:1
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作者 汤海亮 朱剑虹 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第4期241-248,共8页
Neural stem cell is presently the research hotspot in neuroscience. Recent progress indicates that epigenetic modulation is closely related to the self-renewal and differentiation of neural stem cell. Epigenetics refe... Neural stem cell is presently the research hotspot in neuroscience. Recent progress indicates that epigenetic modulation is closely related to the self-renewal and differentiation of neural stem cell. Epigenetics refer to the study of mitotical/meiotical heritage changes in gene function that cannot be explained by changes in the DNA sequence. Major epigenetic mechanisms include DNA methylation, histone modification, chromatin remodeling, genomic imprinting, and non-coding RNA. In this review, we focus on the new insights into the epigenetic mechanism for neural stem cells fate. 展开更多
关键词 stem cells EPIGENESIS neuron restrictive silencer element genomic imprinting H19 non-coding RNA
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cDNA Cloning and Expression Analysis of Mest Gene in the Bufo gargarizans
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作者 王晶晶 聂刘旺 +1 位作者 贾瑞 汪宁 《Zoological Research》 CAS CSCD 北大核心 2009年第4期369-376,共8页
The Mest (mesoderm-specific transcript) gene has been considered an imprinting gene in human and mouse, and was also confirmed in other mammals and flowering plants. To investigate the function and evolution of this... The Mest (mesoderm-specific transcript) gene has been considered an imprinting gene in human and mouse, and was also confirmed in other mammals and flowering plants. To investigate the function and evolution of this gene, the cDNA of full length Mest gene was obtained using 5'- and 3'-RACE from the Chinese Large Toad (Bufo gargarizans). The transcript is 1 325bp in length which contains a complete open reading frame (ORF) encoding a polypeptide of 326 amino acids (GenBank accession number: ABQ10905). There is a typical 0./13 hydrolase fold domain in the putative gene product, and it shows high similarity to sequence of homologous protein of Xenopus tropicali (86%), mammlian (70% - 80%). RT-PCR (reverse transcriptase-polymerase chain reaction) analysis demonstrated that the Bufo gargarizans Mest (BgMest) gene is expressed widely in testis, ovary, liver, kidney, spleen, brain, stomach and lung. The conservation of the BgMest gene sequences, protein secondary structure of the BgMest protein, in addition to the expression pattern of the BgMest gene, suggested that the function of BgMest was conserved in amphibians. However, the phylogenetic tree of the imprinting gene of the mammals and other vertebrates examined in this study indicated their divergent origins. 展开更多
关键词 Bufo gargarizans Mest gene Imprinting gene RACE RT-PCR
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Analysis and improvement of defect-formation of the strip surface in the hot dip strip coating
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作者 LI Wentian and GONG Junjie Hebei Iron & Steel Group Co.,Ltd.,TangSteel,Tangshan 063000,HeBei,China 《Baosteel Technical Research》 CAS 2010年第S1期42-,共1页
In combination with the process technology and equipment at Tangsteel Cold Rolling Mill's 3~# galvanized line,the mechanism of defect-formation of the strip surface in the hot dip galvanized coating has been analy... In combination with the process technology and equipment at Tangsteel Cold Rolling Mill's 3~# galvanized line,the mechanism of defect-formation of the strip surface in the hot dip galvanized coating has been analyzed.Through a series of reform about technology and equipment good solved the defects has been focused on in this paper.The strip surface quality in the hot dip galvanized coating has been improved a lot. 展开更多
关键词 hot galvanizing sink roll imprints dross band strating material scratches stretcher strains chromating defects
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