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文章研究了超声激活血卟啉对人体肿瘤细胞K562的作用以及声辐照剂量和血卟啉浓度对瘤细胞杀伤率的影响。结果表明,声辐射剂量和血卟啉浓度和瘤细胞杀伤率呈正相关系。当频率为1.8MHz、声强度为1.5W/cm^2、作用时间为60s、血卟啉浓度为200μg/mL时,超声激活血卟啉对K562肿瘤作用效果较佳,杀伤率达98%,超声单独作用仅为42%,单纯血卟啉无抗肿瘤效应。 相似文献
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动态聚焦超声换能器的研究与设计 总被引:1,自引:0,他引:1
介绍了为超声激活血卟啉抗肿瘤效应而研究的动态聚焦超声换能器。它是由6个等间距,等宽度的同心圆环和1个中心圆片组成的7元平面 能器阵。通过改变辐射孔径和每个阵元电激励信号的延迟时间,实现动态聚焦衣在各聚焦处声强度一致,导出了聚焦声场声压分布表达式,并设计出换能器的具体结构参数。 相似文献
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再生微粉是以混凝土、砖瓦等为主要成分的建筑垃圾制备再生骨料过程中产生的粒径小于75μm的颗粒,其主要化学组成与粉煤灰类似,具有一定的潜在活性。将再生微粉作为掺合料使用,可减少对原材料的需求,减轻对环境的污染,实现资源的循环利用。再生微粉具有组成复杂、需水量大、活性指数低等特点,直接作为掺合料使用不利于砂浆或混凝土的性能,但再生微粉中SiO2、CaO和Al2O3含量均较高,具有较好的活性潜质,经过适当的技术处理后可以有效激发其活性,提高利用效率。目前再生微粉主要激活方式有物理激活、化学激活和热激活。热激活可以燃尽再生微粉中的有机物杂质,改变部分物质组成,从而激发其活性;物理激活通过机械力增大了再生微粉的比表面积,从而提高了再生微粉活性;化学激活主要通过加入碱性激发剂等提供碱性环境或提供可参与反应的离子,从而促进水化程度提高再生微粉活性。相关学者对再生微粉的活性激发方法及其在砂浆和混凝土中的应用进行了深入研究,这对再生微粉的应用具有积极作用。本文基于已有文献资料,对再生微粉的物理性能、化学组成、激活方式、激活机理及应用现状进... 相似文献
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Aziz Maleki Mohammad Seyedhamzeh Meng Yuan Tarun Agarwal Ibrahim Sharifi Abbas Mohammadi Pelin Kelicen-Uğur Mehrdad Hamidi Massoud Malaki Abdulaziz A. Al Kheraif Ziyong Cheng Jun Lin 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(12):2206253
Sonodynamic therapy (SDT) has considerably revolutionized the healthcare sector as a viable noninvasive therapeutic procedure. It employs a combination of low-intensity ultrasound and chemical entities, known as a sonosensitizer, to produce cytotoxic reactive oxygen species (ROS) for cancer and antimicrobial therapies. With nanotechnology, several unique nanoplatforms are introduced as a sonosensitizers, including, titanium-based nanomaterials, thanks to their high biocompatibility, catalytic efficiency, and customizable physicochemical features. Additionally, developing titanium-based sonosensitizers facilitates the integration of SDT with other treatment modalities (for example, chemotherapy, chemodynamic therapy, photodynamic therapy, photothermal therapy, and immunotherapy), hence increasing overall therapeutic results. This review summarizes the most recent developments in cancer therapy and tissue engineering using titanium nanoplatforms mediated SDT. The synthesis strategies and biosafety aspects of Titanium-based nanoplatforms for SDT are also discussed. Finally, various challenges and prospects for its further development and potential clinical translation are highlighted. 相似文献
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Shuang Liang Xiaoran Deng Ping'an Ma Ziyong Cheng Jun Lin 《Advanced materials (Deerfield Beach, Fla.)》2020,32(47):2003214
Ultrasound (US)-triggered sonodynamic therapy (SDT), as a promising noninvasive therapeutic modality, has received ever-increasing attention in recent years. Its specialized chemical agents, named sonosensitizers, are activated by low-intensity US to produce lethal reactive oxygen species (ROS) for oncotherapy. Compared with phototherapeutic strategies, SDT provides many noteworthy opportunities and benefits, such as deeper penetration depth, absence of phototoxicity, and fewer side effects. Nevertheless, previous studies have also demonstrated its intrinsic limitations. Thanks to the facile engineering nature of nanotechnology, numerous novel nanoplatforms are being applied in this emerging field to tackle these intrinsic barriers and achieve continuous innovations. In particular, the combination of SDT with other treatment strategies has demonstrated a superior efficacy in improving anticancer activity relative to that of monotherapies alone. Therefore, it is necessary to summarize the nanomaterial-assisted combinational sonodynamic cancer therapy applications. Herein, the design principles in achieving synergistic therapeutic effects based on nanomaterial engineering methods are highlighted. The ultimate goals are to stimulate the design of better-quality combined sonodynamic treatment schemes and provide innovative ideas for the perspectives of SDT in promoting its future transformation to clinical application. 相似文献
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Micro/Nanoparticle‐Augmented Sonodynamic Therapy (SDT): Breaking the Depth Shallow of Photoactivation 下载免费PDF全文
The fast development of photoactivation for cancer treatment provides an efficient photo‐therapeutic strategy for cancer treatment, but traditional photodynamic or photothermal therapy suffers from the critical issue of low in vivo penetration depth of tissues. As a non‐invasive therapeutic modality, sonodynamic therapy (SDT) can break the depth barrier of photoactivation because ultrasound has an intrinsically high tissue‐penetration performance. Micro/nanoparticles can efficiently augment the SDT efficiency based on nanobiotechnology. The state‐of‐art of the representative achievements on micro/nanoparticle‐enhanced SDT is summarized, and specific functions of micro/nanoparticles for SDT are discussed, from the different viewpoints of ultrasound medicine, material science and nanobiotechnology. Emphasis is put on the relationship of structure/composition‐SDT performance of micro/nanoparticle‐based sonosensitizers. Three types of micro/nanoparticle‐augmented SDT are discussed, including organic and inorganic sonosensitizers and micro/nanoparticle‐based but sonosensitizer‐free strategies to enhance the SDT outcome. SDT‐based synergistic cancer therapy augmented by micro/nanoparticles and their biosafety are also included. Some urgent critical issues and potential developments of micro/nanoparticle‐augmented SDT for efficient cancer treatment are addressed. It is highly expected that micro/nanoparticle‐augmented SDT will be quickly developed as a new and efficient therapeutic modality which will find practical applications in cancer treatment. At the same time, fundamental disciplines regarding materials science, chemistry, medicine and nanotechnology will be advanced. 相似文献
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Peter A. Hancock Anthony J. Masalonis Raja Parasuraman 《Theoretical Issues in Ergonomics Science》2013,14(3):207-230
This work examines the foundations for and explores the implications of fuzzy signal detection (Fuzzy SDT), a theory that represents the marriage of two powerful extant theories, fuzzy set theory and signal detection theory. Fuzzy SDT permits the modelling and prediction of human, machine, and human-machine performance in a wide range of settings. Fuzzy SDT exploits the strengths of each theory to provide new and dynamic insights into performance. Fuzzy SDT explicitly recognizes that the binary decision states of classic signal detection represent two ends of a single continuum whose uncertainty decreases towards such end states and is maximized in its centre. It is shown how Fuzzy SDT has its origins in some more general concepts of human performance, and companion works are referenced which provide the mathematical foundation for Fuzzy SDT and its application in a specific domain. The present work examines the wider implications of Fuzzy SDT by illustrating the relevance of fuzzification in the larger cycle of design, configuration, and use of technology. It also examines the broader concerns of the temporal relationship between signal and response, showing time to be a crucial, if neglected, dimension of action, the exploration and exploitation of which can produce a deeper understanding of human behaviour in psychology, machine behaviour in engineering and human-machine behaviour in ergonomics. 相似文献
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This article presents an investigation on the buckling of functionally graded (FG) truncated conical shells under an axial load resting on elastic foundations within the shear deformation theory (SDT). The governing equations are solved using the Galerkin method, and the closed-form solution of the axial buckling load for FG conical shells on elastic foundations within the SDT is obtained. Various numerical examples are presented and discussed to verify the accuracy of the closed-form solution in predicting dimensionless buckling loads for FG conical shells on the Winkler–Pasternak elastic foundations within the SDT. 相似文献
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Xianshuo Cao Minxing Li Qiyu Liu Jingjing Zhao Xihong Lu Jianwei Wang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(42):2303195
The rapid development of nanomedicine and nanobiotechnology has allowed the emergence of various therapeutic modalities with excellent therapeutic efficiency and biosafety, among which, the sonodynamic therapy (SDT), a combination of low-intensity ultrasound and sonosensitizers, is emerging as a promising noninvasive treatment modality for cancer treatment due to its deeper penetration, good patient compliance, and minimal damage to normal tissue. The sonosensitizers are indispensable components in the SDT process because their structure and physicochemical properties are decisive for therapeutic efficacy. Compared to the conventional and mostly studied organic sonosensitizers, inorganic sonosensitizers (noble metal-based, transition metal-based, carbon-based, and silicon-based sonosensitizers) display excellent stability, controllable morphology, and multifunctionality, which greatly expand their application in SDT. In this review, the possible mechanisms of SDT including the cavitation effect and reactive oxygen species generation are briefly discussed. Then, the recent advances in inorganic sonosensitizers are systematically summarized and their formulations and antitumor effects, particularly highlighting the strategies for optimizing the therapeutic efficiency, are outlined. The challenges and future perspectives for developing state-of-the-art sonosensitizers are also discussed. It is expected that this review will shed some light on future screening of decent inorganic sonosensitizers for SDT. 相似文献
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随着纳米医学的发展, 利用纳米材料在外源超声波的刺激下催化产生过量的活性氧物种(Reactive Oxygen Species, ROS)以治疗疾病的方法, 被称为声动力疗法(Sonodynamic Therapy, SDT), 已引起人们的广泛关注。目前, 开发可用于SDT的高效声敏剂用于提高ROS产率, 仍然是当前研究和未来临床转化的最大挑战之一。近年来, 得益于压电电子学和压电光电子学的兴起, 基于压电半导体纳米材料的新型声敏剂在SDT中崭露头角, 显示出良好的应用前景。本文从压电半导体的结构出发, 介绍了压电半导体纳米材料应用于SDT的机理研究, 以及利用压电半导体纳米材料作为声敏剂在声动力学癌症治疗及相关抗菌性能方面所取得的研究进展。最后, 本文对该领域存在的问题以及未来的发展趋势进行了展望。 相似文献
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The aim of present study is to investigate the dynamic instability of exponentially graded (EG) sandwich cylindrical shells under static and time dependent periodic axial loadings using the shear deformation theory (SDT). The modified Donnell-type dynamic instability equations of EG sandwich cylindrical shells based on the SDT are deduced. Then are reduced to Mathieu-Hill equation and by solving the expressions for the boundaries of instability regions of EG sandwich cylindrical shells are obtained. The similar expressions for EG single-layer shell, ceramic-rich shell and metal coated sandwich cylindrical shell on the basis of SDT and classical shell theory (CST) are obtained in a special case. The numerical illustrations concern the influences of compositional profiles of coating layers, shear stresses and geometrical parameters of sandwich cylindrical shells on the boundaries of instability regions. As a check on the accuracy of the present study, the values of the lower and upper boundaries of instability regions are compared with those in the literature. 相似文献
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This paper describes the use of the Stiffness Damage Test (SDT) technique for quantifying the degree of deterioration experienced by thermally loaded concretes. The applicability of the SDT for assessing temperature damaged concrete has been experimentally investigated and analysed. Results have shown the SDT parameters to be sensitive to the influences of test age, the level of temperature exposure and the degree of damage caused by that exposure. A strong and consistent degree of correlation between the results obtained from the SDT and the standard test measurements (compressive strength, static modulus and ultrasonic pulse velocity) has been found. The use of the SDT as a tool for detecting pre-damage and the development of microcracking in concrete specimens subjected to compressive loading have been confirmed by Acoustic Emission (AE) test techniques. 相似文献
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Yiming Ding Yunchao Zhao Shuncheng Yao Shaobo Wang Xingyi Wan Quanhong Hu Linlin Li 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(24):2300327
Sonodynamic therapy (SDT) is regarded as a new-rising strategy for cancer treatment with low invasiveness and high tissue penetration, but the scarcity of high-efficiency sonosensitizers has seriously hindered its application. Herein, the iron-doped and oxygen-deficient bismuth tungstate nanosheets (BWO-Fe NSs) with piezotronic effect are synthesized for enhanced SDT. Due to the existence of oxygen defects introduced through Fe doping, the bandgap of BWO-Fe is significantly narrowed so that BWO-Fe can be more easily activated by exogenous ultrasound (US). The oxygen defects acting as the electron traps inhibit the recombination of US-induced electrons and holes. More importantly, the dynamically renewed piezoelectric potential facilitates the migration of electrons and holes to opposite side and causes energy band bending, which further promotes the production of reactive oxygen species. Furthermore, Fe doping endows BWO-Fe with Fenton reactivity, which converts hydrogen peroxide (H2O2) in tumor microenvironment into hydroxyl radicals (•OH), thereby amplifying the cellular oxidative damage and enhancing SDT. Both in vitro and in vivo experiments illustrate their high cytotoxicity and tumor suppression rate against refractory breast cancer in mice. This work may provide an alternative strategy to develop oxygen-deficient piezoelectric sonosensitizers for enhanced SDT via doping metal ions. 相似文献