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71.
Tsung-Han Ho Chien-Hsin Yang Zheng-En Jiang Hung-Yin Lin Yih-Fung Chen Tzong-Liu Wang 《International journal of molecular sciences》2022,23(15)
To date, the increase in reactive oxygen species (ROS) production for effectual photodynamic therapy (PDT) treatment still remains challenging. In this study, a facile and effective approach is utilized to coat mesoporous silica (mSiO2) shell on the ligand-free upconversion nanoparticles (UCNPs) based on the LiYF4 host material. Two kinds of mesoporous silica-coated UCNPs (UCNP@mSiO2) that display green emission (doped with Ho3+) and red emission (doped with Er3+), respectively, were successfully synthesized and well characterized. Three photosensitizers (PSs), merocyanine 540 (MC 540), rose bengal (RB), and chlorin e6 (Ce6), with the function of absorption of green or red emission, were selected and loaded into the mSiO2 shell of both UCNP@mSiO2 nanomaterials. A comprehensive study for the three UCNP@mSiO2/PS donor/acceptor pairs was performed to investigate the efficacy of fluorescence resonance energy transfer (FRET), ROS generation, and in vitro PDT using a MCF-7 cell line. ROS generation detection showed that as compared to the oleate-capped and ligand-free UCNP/PS pairs, the UCNP@mSiO2/PS nanocarrier system demonstrated more pronounced ROS generation due to the UCNP@mSiO2 nanoparticles in close vicinity to PS molecules and a higher loading capacity of the photosensitizer. As a result, the three LiYF4 UCNP@mSiO2/PS nanoplatforms displayed more prominent therapeutic efficacies in PDT by using in vitro cytotoxicity tests. 相似文献
72.
Sing Teang Kong Hai-Shu Lin Jianhong Ching Huiqing Xie Paul C. Ho 《International journal of molecular sciences》2022,23(13)
The immediate and delayed metabolic changes in rats treated with valproate (VPA), a drug used for the treatment of epilepsy, were profiled. An established approach using dried blood spots (DBS) as sample matrices for gas chromatography/mass spectrometry-based metabolomics profiling was modified using double solvents in the extraction of analytes. With the modified method, some of the previously undetectable metabolites were recovered and subtle differences in the metabolic changes upon exposure to a single dose of VPA between males and female rats were identified. In male rats, changes in 2-hydroxybutyric acid, pipecolic acid, tetratriacontane and stearic acid were found between the control and treatment groups at various time points from 2.5 h up to 24 h. In contrast, such differences were not observed in female rats, which could be caused by the vast inter-individual variations in metabolite levels within the female group. Based on the measured DBS drug concentrations, clearance and apparent volume of distribution of VPA were estimated and the values were found to be comparable to those estimated previously from full blood drug concentrations. The current study indicated that DBS is a powerful tool to monitor drug levels and metabolic changes in response to drug treatment. 相似文献
73.
采用石墨炉原子吸收光谱法(GFAAs)测定锂离子电池正极材料LiMn2O4中杂质Pb和Cd的含量.探讨了HNO2浓度、Pb和Cd的灰化温度和原子化温度、基体改进剂对测定结果的影响.该方法的操作简单,准确度高,Pb的回收率为91.22%~93.75%,Cd的回收率为96.5%~108.6%;精密度好,两种元素测定的相对标准偏差RSD(n=lO)<5%. 相似文献
74.
Enhua Hao Yini Li Bing Guo Xi Yang Pengfei Lu Haili Qiao 《International journal of molecular sciences》2022,23(15)
Sirex noctilio Fabricius (Hymenoptera Siricidae) is a major quarantine pest responsible for substantial economic losses in the pine industry. To achieve better pest control, (Z)-3-decen-ol was identified as the male pheromone and used as a field chemical trapping agent. However, the interactions between odorant-binding proteins (OBPs) and pheromones are poorly described. In this study, SnocOBP9 had a higher binding affinity with Z3D (Ki = 1.53 ± 0.09 μM) than other chemical ligands. Molecular dynamics simulation and binding mode analysis revealed that several nonpolar residues were the main drivers for hydrophobic interactions between SnocOBP9 and Z3D. Additionally, computational alanine scanning results indicated that five amino acids (MET54, PHE57, PHE71, PHE74, LEU116) in SnocOBP9 could potentially alter the binding affinity to Z3D. Finally, we used single-site-directed mutagenesis to substitute these five residues with alanine. These results imply that the five residues play crucial roles in the SnocOBP9-Z3D complex. Our research confirmed the function of SnocOBP9, uncovered the key residues involved in SnocOBP9-Z3D interactions, and provides an inspiration to improve the effects of pheromone agent traps. 相似文献
75.
基于政府规制的发电市场结构演进及国际实践 总被引:1,自引:0,他引:1
通过政府规制下各国发电市场结构演进实践的考察和分析,认为政府利用准入规制控制了发电市场主体进入市场,是政府对发电市场结构进行规制的主要手段,决定着竞争性发电市场结构的形成;政府对市场力的规制可以防止发电商滥用市场力逐利,损害竞争,导致社会福利无谓损失,保护着竞争性发电市场结构形成.结论是政府规制对发电市场结构的演进起着决定性作用. 相似文献
76.
Image morphing: a survey 总被引:29,自引:0,他引:29
George Wolberg 《The Visual computer》1998,14(8-9):360-372
77.
Title of program: CATAR Catalogue number: ABGP Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland (see application form in this issue) Computer: UNIVAC 1108; Installation: Sandoz A.G., Basel, Switzerland Operating system: EXEC 8 Programming language used: FORTRAN IV High speed store required: 26K words No. of bits in a word: 36 Overlay structure: None Number of magnetic tapes required: None Other peripherals used: Card reader, line printer Number of cards in combined program and test deck: 3136 Card punching code: BCD 相似文献
78.
79.
光伏发电技术是可再生能源技术的一个重要组成部分。介绍了500 kV芝堰变电站光伏并网发电系统,采集了光伏并网发电的数据,分析、模拟计算太阳能光伏系统的效益,在此基础上总结光伏发电系统使用中的优点及存在的问题。 相似文献
80.
针对传统自动发电控制(AGC)优化模型中难以考虑市场力风险的问题,引入度量市场风险的价值模型,提出了以风险价值为限值的辅助服务成本约束混合整数非线性规划的AGC优化模型。为处理模型的非线性,引入两态辅助变量,将三态的机组状态变量进行等效转化,实现了模型的线性化,有效地降低了模型求解难度。以广西电网运行数据为例,对比不同风险置信水平下AGC控制性能,结果表明:置信水平越高,调节成本越大,控制效果越好,但无论置信水平高低,所提模型均能确保控制性能标准(CPS)合格,验证了模型的有效性,为电力市场环境下的AGC控制提供了有益参考。 相似文献