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91.
放射治疗是利用放射线治疗肿瘤的一种局部治疗方法,目前已成为临床上最常用、最有效的恶性肿瘤治疗手段之一。但放射治疗仍存在辐射剂量高、对健康组织副作用大,特别是肿瘤细胞放射抵抗性强等缺点。随着纳米医学的发展,多功能纳米放疗增敏剂为增强肿瘤细胞放射敏感性、提高放疗效果提供了新机遇。本文结合纳米材料在放疗增敏中的优势和潜能,概括了纳米放疗增敏剂的主要类型和目前已进入临床实验的一些实例,简述了多功能纳米放疗增敏剂在肿瘤放射治疗中的应用,并归纳了纳米材料增敏放疗的主要途径和影响因素。最后总结和展望了多功能纳米放疗增敏剂面临的挑战和发展前景。 相似文献
92.
We present a novel reference compensation method for eliminating environmental noise in interferometric wavelength shift demodulation for dynamic fiber Bragg grating (FBG) sensors. By employing a shielded wavelength-division-multiplexed reference FBG in the system, the environmental noise is measured from the reference channel, and then subtracted from the demodulation result of each sensor channel. An approximate 40 dB reduction of the environmental noise has been experimentally achieved over a frequency range from 20 Hz to 2 kHz. This method is also suitable for the elimination of broadband environmental noise. The corresponding FBG sensor array system proposed in this paper has shown a wavelength resolution of . 相似文献
93.
We present the detection of the shape-specific conformation of DNA based on the fluorescence resonance energy transfer (FRET) by using a novel flexible water-soluble cationic conjugated polymer (CCP). The flexible backbone of CCP has more conformational freedom with the potential to be responsive to analyte shape by electrostatic interaction between flexible CCP and negatively charged DNA. The analyte shape dependent recognition is accomplished by structural changes that compressed or extended the flexible CCP. The morphology-dependent spectral properties of the novel flexible polymer related to the analyte shapes are investigated in detail, where two types of chromophores, referred to as "isolated" segment and "packed" segment aggregates, within the flexible polymer are identified by means of ensemble and single molecule measurements upon binding with different geometric DNA. The change in fluorescence intensity upon binding with shape-specific DNA without obvious color shifts makes this novel flexible polymer a suitable CCP donor for FRET measurements. The results provide insights for understanding the spectral properties of flexible water-soluble CCP and CCP/DNA interaction related to the geometry of target analyte. 相似文献
94.
95.
为高效求解球床高温气冷堆物理-热工耦合问题,发展改进节块展开法求解圆柱几何下的对流扩散方程.针对圆柱几何和对流扩散方程的特殊性,采用三阶多项式和指数函数作为r向横向积分方程的展开函数,在节块展开法的框架下高效求解对流扩散方程.数值验证表明,改进的节块展开方法具有固有的迎风特性,在使用粗网节块时依然能保持稳定性和较高的计算精度. 相似文献
96.
Fluoroethylene carbonate (FEC) is investigated as the electrolyte additive to improve the electrochemical performance of high voltage LiNi0.6Co0.2Mn0.2O2 cathode material. Compared to LiNi0.6Co0.2Mn0.2O2/Li cells in blank electrolyte, the capacity retention of the cells with 5 wt% FEC in electrolytes after 80 times charge-discharge cycle between 3.0 and 4.5 V significantly improve from 82.0 to 89.7%. Besides, the capacity of LiNi0.6Co0.2Mn0.2O2/Li only obtains 12.6 mAh g?1 at 5 C in base electrolyte, while the 5 wt% FEC in electrolyte can reach a high capacity of 71.3 mAh g?1 at the same rate. The oxidative stability of the electrolyte with 5 wt% FEC is evaluated by linear sweep voltammetry and potentiostatic data. The LSV results show that the oxidation potential of the electrolytes with FEC is higher than 4.5 V vs. Li/Li+, while the oxidation peaks begin to appear near 4.3 V in the electrolyte without FEC. In addition, the effect of FEC on surface of LiNi0.6Co0.2Mn0.2O2 is elucidated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The analysis result indicates that FEC facilitates the formation of a more stable surface film on the LiNi0.6Co0.2Mn0.2O2 cathode. The electrochemical impedance spectroscopy (EIS) result evidences that the stable surface film could improve cathode electrolyte interfacial resistance. These results demonstrate that the FEC can apply as an additive for 4.5 V high voltage electrolyte system in LiNi0.6Co0.2Mn0.2O2/Li cells. 相似文献
97.
98.
Transformable Peptide Nanocarriers for Expeditious Drug Release and Effective Cancer Therapy via Cancer‐Associated Fibroblast Activation
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Tianjiao Ji Dr. Ying Zhao Dr. Yanping Ding Jing Wang Ruifang Zhao Jiayan Lang Hao Qin Xiaoman Liu Jian Shi Dr. Ning Tao Prof. Dr. Zhihai Qin Prof. Dr. Guangjun Nie Prof. Dr. Yuliang Zhao 《Angewandte Chemie (International ed. in English)》2016,55(3):1050-1055
A novel cleavable amphiphilic peptide (CAP) was designed to be specifically responsive to fibroblast activation protein‐α (FAP‐α), a protease specifically expressed on the surface of cancer‐associated fibroblasts. The CAP self‐assembled into fiber‐like nanostructures in solution, while the presence of hydrophobic chemotherapeutic drugs readily transformed the assemblies into drug‐loaded spherical nanoparticles. The disassembly of these nanoparticles (CAP‐NPs) upon FAP‐α cleavage resulted in rapid and efficient release of the encapsulated drugs specifically at tumor sites. This Transformers‐like drug delivery strategy could allow them to disrupt the stromal barrier and enhance local drug accumulation. Therapeutic results suggested that drug‐loaded CAP‐NPs hold promising tumor specificity and therapeutic efficacy for various solid tumor models, confirming its potential utility and versatility in antitumor therapy. 相似文献
99.
Dr. Yanwen Yu Dr. Qinghua Shi Prof. Yongjun Li Dr. Taifeng Liu Dr. Liang Zhang Prof. Zhigang Shuai Prof. Yuliang Li 《化学:亚洲杂志》2012,7(12):2904-2911
A new p‐phenylenevinylene‐linked perylene diimide has been synthesized and self‐assembled for the formation of zero‐dimensional molecular aggregate structures of nanospheres and vesicles through solvent tuning. The solid‐state optical properties induced by a special wavelength laser were studied and the results indicated excellent fluorescent enhancement properties. The emission intensity of these aggregates increased with elongation of the laser irradiation time. Based on the analysis of variable‐temperature 1H NMR spectra, DFT calculations, and the single‐crystal structure of the linkage group, a conformation‐dependent fluorescent enhancement mechanism could be demonstrated. The mechanism is different from the fluorescent bleaching of normal solid‐state fluorescent materials and offers potential applications in optical devices. 相似文献
100.
Qian X Ning Z Li Y Liu H Ouyang C Chen Q Li Y 《Dalton transactions (Cambridge, England : 2003)》2012,41(3):730-733
GDNWs (graphdiyne nanowires) have successfully been constructed which exhibit a very high quality defect-free surface using the VLS growth process. Measurement of electrical properties showed that the GDNWs produced are excellent semiconductors with a conductivity of 1.9 × 10(3) S m(-1) and a mobility of 7.1 × 10(2) cm(2) V(-1) s(-1) at room temperature. The results have confirmed that GDNW is indeed a promising and key novel material in electronic and photoelectric fields for both fundamental and potentially practical applications. 相似文献