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111.
聚集诱导发光(AIE)现象的发现为解决传统有机荧光分子在高浓度和聚集形态下存在的荧光猝灭问题提供了最佳方案,并实现了在光电器件、化学传感、生物成像和靶向治疗等众多领域的广泛应用.随着对AIE 发光机理研究的不断深入,AIE 分子体系得到了极大的扩展.其中,一类具有给体-受体结构的AIE分子能够显著降低分子能隙,使发光分...  相似文献   
112.
113.
PDT光敏剂HA在不同液相体系下的光谱特性研究   总被引:2,自引:2,他引:0  
为了对候选光敏剂竹红菌甲素(HA)进行改性并保持其优异的敏化特性,对HA的光谱特性和激发态性质作了进一步的指认。系统研究了HA在不同液相体系下的吸收和荧光光谱,对指认HA的光谱和电子跃迁的机制提出了新的依据,结果表明,吸收带I产生于π-π*跃迁,吸收带Ⅱ和Ⅲ产生于P-π共轭所导致的L→aπ跃迁的电子振动结构;荧光发射带I和Ⅱ是产生于同一跃迁机制S1(L,aπ)→S0的正常荧光的振动结构。  相似文献   
114.
Polymyxin-based combination therapy is commonly used to treat carbapenem-resistant Acinetobacter baumannii (CRAB) infections. In the present study, the bactericidal effect of polymyxin B and minocycline combination was tested in three CRAB strains containing blaOXA-23 by the checkerboard assay and in vitro dynamic pharmacokinetics/pharmacodynamics (PK/PD) model. The combination showed synergistic or partial synergistic effect (fractional inhibitory concentration index ≤0.56) on the tested strains in checkboard assays. The antibacterial activity was enhanced in the combination group compared with either monotherapy in in vitro PK/PD model. The combination regimen (simultaneous infusion of 0.75 mg/kg polymyxin B and 100 mg minocycline via 2 h infusion) reduced bacterial colony counts by 0.9–3.5 log10 colony forming units per milliliter (CFU/mL) compared with either drug alone at 24 h. In conclusion, 0.75 mg/kg polymyxin B combined with 100 mg minocycline via 2 h infusion could be a promising treatment option for CRAB bloodstream infections.  相似文献   
115.
李海荣  蒋舸扬  金林  李乾楠  李瑞  沈立人 《强激光与粒子束》2020,32(4):045108-1-045108-6
针对质子治疗装置中主环动态电源多平台能量的引出需求,研制了基于开源平台的高速实时动态电源控制系统,该控制系统以开源平台Beaglebone作为顶层硬件接口,以现场可编程逻辑门阵列(FPGA)为核心的控制器作为底层硬件接口,采用分布式的实验物理及工业控制系统(EPICS)进行远程控制。该系统可实时传输任意动态电源的输出参考电流波形数据,并结合定时系统与联锁系统,控制动态电源按预设电流波形进行输出,并实现多平台能量的引出。实验结果显示该控制系统能实现每秒最高十万条指令传输,百万次数据传输零误码率。同时,该系统结构灵活、扩展性强,可作为通用控制平台。  相似文献   
116.
Multimodal approaches combined with various nanomaterials and advanced techniques have been developed for synergistic cancer treatment. Among various therapies, conventional chemotherapy (CHT) is a direct cancer treatment that can produce unintended side effects due to nonspecific action on both the tumor and normal cells; patient-friendly photothermal therapy (PTT) may be able to treat embedded tumors in vital regions with minimal invasion but does not guarantee complete removal of cancers. However, the combination of CHT-PTT may provide a promising tool for direct cancer treatment with minimal side effects. In this regard, nanostructured materials, such as gold nanorods with tuned size and surface characteristics, are key components designed to enhance the heating capacity and active or passive delivery of drugs to the tumor site. In this review, the pioneering work synergizing CHT and PTT is summarized, and the current state-of-the-art in the development of inorganic and organic nanocomposites for combinational therapy is described.  相似文献   
117.
Black phosphorus nanosheet (BPNS) is a promising multifunctional material in the biomedical field with biodegradability and low side effects, however its features are always weakened severely owing to its poor stability. Here, a novel method is developed for improving the defect of BPNS based on the effective protection of poly(lactic-co-glycolic acid) (PLGA), which preserves the stable photothermal therapy (PTT) effect of BPNS and biodegradability of the material. Meanwhile, doxorubicin (DOX) is loaded on BPNS/PLGA to get BPNS/PLGA/DOX for further chemotherapy and preventing the recurrence of tumor after PTT. The presented combined therapeutic strategy exploits the strengths and improves the defects of BPNS, thus developing an efficient and safe nanoagent for cancer therapy, which affords and reveals the great potential of BPNS in nanomedicine.  相似文献   
118.
Photosensitizers that can target and accumulate in mitochondria are expected to achieve good therapeutic effects in photodynamic therapy,as mitochondria are the energy generation factory in cells.Herein,we designed and synthesized a novel mitochondrion-targeting photosensitizer TPC-Py with aggregation-induced emission characteristics for image-guided photodynamic therapy.TPC-Py possessed an efficient production of 1O2,with a quantum yield of 11.65%,upon mild white light irradiation(6 mW/cm2).TPC-Py exhibited good biocompatibility under dark condition,but showed remarkable cytotoxicity towards human cervical carcinoma(HeLa)cells with a half maximal inhibitory concentration(IC50)of 3.2μmol/L when exposed to white light irradiation(14.4 J/cm2).In addition,the Stokes shift of TPC-Py was as high as 150 nm,so that it could prevent self-absorption and increase the signal-to-noise ratio of fluorescence imaging.The excellent performance of TPC-Py makes it a promising candidate in imaging-guided clinical PDT for cancer in the near future.  相似文献   
119.
Nitric oxide is a ubiquitous signaling radical that influences critical body functions. Its importance in the cardiovascular system and the innate immune response to bacterial and viral infections has been extensively investigated. The overproduction of NO is an early component of viral infections, including those affecting the respiratory tract. The production of high levels of NO is due to the overexpression of NO biosynthesis by inducible NO synthase (iNOS), which is involved in viral clearance. The development of NO-based antiviral therapies, particularly gaseous NO inhalation and NO-donors, has proven to be an excellent antiviral therapeutic strategy. The aim of this review is to systematically examine the multiple research studies that have been carried out to elucidate the role of NO in viral infections and to comprehensively describe the NO-based antiviral strategies that have been developed thus far. Particular attention has been paid to the potential mechanisms of NO and its clinical use in the prevention and therapy of COVID-19.  相似文献   
120.
As one of the key phosphatidylinositol 3-kinase-related kinases (PIKKs) family members, ataxia telangiectasia and RAD3-related protein kinase (ATR) is crucial in maintaining mammalian cell genomic integrity in DNA damage response (DDR) and repair pathways. Dysregulation of ATR has been found across different cancer types. In recent years, the inhibition of ATR has been proven to be effective in cancer therapy in preclinical and clinical studies. Importantly, tumor-specific alterations such as ATM loss and Cyclin E1 (CCNE1) amplification are more sensitive to ATR inhibition and are being exploited in synthetic lethality (SL) strategy. Besides SL, synergistic anticancer effects involving ATRi have been reported in an increasing number in recent years. This review focuses on the recent advances in different forms of synergistic antitumor effects, summarizes the pharmacological benefits and ongoing clinical trials behind the biological mechanism, and provides perspectives for future challenges and opportunities. The hope is to draw awareness to the community that targeting ATR should have great potential in developing effective anticancer medicines.  相似文献   
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