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21.
Yong Guan Huanyao Zhang Anna Zheng Dafu Wei Jian Hu Zhenzhen Wang Xiang Xu 《先进技术聚合物》2019,30(7):1555-1563
Recently, silicone rubber (VMQ) was extensively used in household articles and medical devices. To develop a kind of safe and long‐term antimicrobial VMQ was of great significance. In this work, a kind of vinyl‐contained polyhexamethylene guanidine hydrochloride (VPHMG) was synthesized and used as antimicrobial additive for VMQ. With the increasing of VPHMG addition, the mechanical properties and antimicrobial properties of VMQ‐VPHMG were significantly improved. In particular, the antimicrobial rates against Escherichia coli and Staphylococcus aureus were higher than 99.99% as for 4 wt% of VPHMG addition. Moreover, the surface concentration of VPHMG as well as the antimicrobial rates revealed almost unchanged after being extracted by water and methanol. All the results indicated the vinyl‐contained VPHMG vulcanization and therefore provided the permanent antimicrobial performance for VMQ. 相似文献
22.
Zhongzheng Yu Wenbo Hu Hui Zhao Xiaofei Miao Yan Guan Weizheng Cai Zhiping Zeng Quli Fan Timothy Thatt Yang Tan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(25):8624-8628
Cross‐relaxation among sensitizers is commonly regarded as deleterious in fluorescent materials, although favorable in photothermal agents. Herein, we coated Prussian blue (PB) on NaNdF4 nanoparticles to fabricate core–shell nanocomplexes with new cross relaxation pathways between the ladder‐like energy levels of Nd3+ ions and continuous energy band of PB. The photothermal conversion efficiency was improved exceptionally and the mechanism of the enhanced photothermal effect was investigated. In vivo photoacoustic imaging and photothermal therapy demonstrated the potential of the enhanced photothermal agents. Moreover, the concept of generating new cross‐relaxation pathways between different materials is proposed to contribute to the design of all kinds of enhanced photothermal agents. 相似文献
23.
Here we present a novel design of electrochemical signal enhancer to increase the detection sensitivity of electrochemical DNA biosensors. The key element of this enhancer is a lysine‐rich peptide (LRP). Its C‐terminal is conjugated with a planer molecule, being able to intercalate into the base pairs of probe‐target duplexes. The lysine residues of LRP are covalently linked with electrochemical signal indicators, acting as an assembly of electrochemical signal indicators. Experimental results proved the feasibility of the novel design. We have examined the effects of the numbers of lysine residues and the hybridization conditions on the detection sensitivity. The optimization procedures have led to significant sensitivity enhancement, and the LOD (limit of detection) has been determined to be 1.4 amol. This enhancer demonstrates advantages of easy operation, simple instrumentation, and high exemption from environmental influence. 相似文献
24.
A new capillary electrophoresis method was developed to study the synergistic effect of superoxide dismutase and jujuboside A or B on scavenging superoxide anion radical in serum matrix respectively, in which superoxide anion radical was generated from pyrogallol autoxidation. The electrophoresis conditions, and the factors affecting the productive rate of purpurogallin, such as pyrogallol autoxidation product and the activity of superoxide dismutase, were optimized. Under optimal conditions, the content of superoxide dismutase in Gibco newborn calf serum was 7.06 mg/L, RSD was 2.01% and the average recovery was 98.4%. The values of IC50 for jujuboside A and B in the serum matrix were 157.67 and 31.60 mg/L respectively, and they both had synergy on scavenging superoxide anion radical with superoxide dismutase, but there was no the dose‐dependency on this synergy. 相似文献
25.
Yan‐Ping Zhang Yue Li Guan‐Cheng Xu Jin‐Yu Li Hua‐Ying Luo Jin‐Yao Li Li Zhang Dian‐Zeng Jia 《应用有机金属化学》2019,33(3)
Two new complexes, namely [Cu6L6] ( 1 ) and [Zn(HL)2] ( 2 ) (H2L = N‐(1‐phenyl‐3‐methyl‐4‐propenylidene‐5‐pyrazolone)‐2‐furancarboxylic acid hydrazide), have been synthesized and characterized. Single crystal X‐ray analysis indicates that complex 1 has a hexanuclear structure and complex 2 exhibits a mononuclear structure. The DNA/bovine serum albumin (BSA) binding properties of complexes 1 and 2 were investigated by absorption spectroscopy and fluorescence quenching. Both complexes could effectively intercalate to DNA with calculated quenching constants of 2.6 × 105 and 1.25 × 105 M?1, respectively. The quenching mechanism of the intrinsic fluorescence of BSA by the complexes was found to be a static one. The cytotoxicities of 1 and 2 were investigated in two human tumor cell lines, human esophageal cancer cells (Eca‐109) and cervical cancer cells (HeLa). Complex 1 exhibits higher antitumor activity than 2 . Furthermore, 1 can inhibit HeLa cells by inducing apoptosis and G0/G1 phase cell cycle arrest. All results demonstrate that 1 and 2 both have DNA/BSA binding capacity and antitumor activity. 相似文献
26.
This paper concerns with the problem of how to running an insurance company to maximize his total discounted expected dividends. In our model, the dividend rate is limited in and the company is allowed to transfer any proportion of risk by reinsuring. So there are two strategies which we call dividend strategy and reinsurance strategy. The objective function and the corresponding optimal two strategies are the solution and the two free boundaries of the following Barenblatt parabolic equation under certain boundary conditions on an angular domain The main effort is to analyze the properties of the solution and the free boundaries to show the optimal decision for the insurance company. 相似文献
27.
Mian Fu Xiaomei Zhuang Tianhong Zhang Ying Guan Qingbin Meng Yongjun Zhang 《Macromolecular bioscience》2020,20(9)
Leuprolide has been widely used in androgen deprivation therapy for the treatment of advanced prostate cancer, but its use is still limited due to its short half‐life. Herein, hydrogen‐bonded layer‐by‐layer films are fabricated from PEGylated leuprolide (PEG‐LEU) and tannic acid (TA). Because of its dynamic nature, the film disintegrates gradually in water and releases PEG‐LEU and TA. The in vitro release profile indicated perfect zero‐order kinetics, which is explained by the unique release mechanism. When implanted subcutaneously in male rats, the films maintain a constant serum drug level. For a 60‐bilayer film, the serum drug level is maintained constant for ≈24 days. No initial burst release is observed, suggesting that the in vivo release also follows zero‐order kinetics. Initially, an increase in the level of serum testosterone is induced by the released drug, followed by testosterone suppression to a constant level below the castrate level, which could be maintained as long as a constant serum drug level is maintained. Since the new drug carriers avoid an initial burst release of the drug and maintain a constant serum drug level and hence a constant serum testosterone level below the castrate level, these carriers are highly promising for androgen deprivation therapy. 相似文献
28.
Chen Yujie Sang Weixuan Chen Rong Liu Xue Li Xiaoyan Guan Fenfen Li Xun Xiao Hui 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):367-373
Journal of Radioanalytical and Nuclear Chemistry - The nanoscale zero-valent nickel (nano-Ni0) was prepared by liquid-phase reduction method and characterized by BET, XPS, FT-IR and XRD and be used... 相似文献
29.
Dr. Shang-Fu Yuan Wen-Di Liu Dr. Chun-Yu Liu Dr. Zong-Jie Guan Prof. Dr. Quan-Ming Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(24):e202104445
Surface organic ligands are critical in dictating the structures and properties of atomically precise metal nanoclusters. In contrast to the conventionally used thiolate, phosphine and alkynyl ligands, nitrogen donor ligands have not been used in the protection for well-defined metal nanoclusters until recently. This review focuses on recent developments in atomically precise metal nanoclusters stabilized by different types of nitrogen donor ligands, in which the synthesis, total structure determination and various properties are covered. We hope that this review will provide insights into the rational design of N donor-protected metal nanoclusters in terms of structural and functional modulation. 相似文献
30.
Journal of Visualization - Convolutional neural networks (CNNs) have achieved breakthrough performance in image recognition and classification. However, it is still a challenge for CNNs to classify... 相似文献