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Mengyu Chang Zhiyao Hou Dayong Jin Jiajia Zhou Man Wang Meifang Wang Mengmeng Shu Binbin Ding Chunxia Li Jun Lin 《Advanced materials (Deerfield Beach, Fla.)》2020,32(43):2004647
Rational design of tumor microenvironment (TME)-activated nanocomposites provides an innovative strategy to construct responsive oncotherapy. In colorectal cancer (CRC), the specific physiological features are the overexpressed endogenous H2S and slightly acidic microenvironment. Here, a core–shell Cu2O@CaCO3 nanostructure for CRC “turn-on” therapy is reported. With CaCO3 responsive to pH decomposition and Cu2O responsive to H2S sulfuration, Cu2O@CaCO3 can be triggered “on” into the therapeutic mode by the colorectal TME. When the CaCO3 shell decomposes and releases calcium in acidic colorectal TME, the loss of protection from the CaCO3 shell exposes the Cu2O core to be sulfuretted by H2S to form metabolizable Cu31S16 nanocrystals that gain remarkably strong near-infrared absorption. After modifying hyaluronic acid, Cu2O@CaCO3 can achieve synergistic CRC-targeted and TME-triggered photothermal/photodynamic/chemodynamic/calcium-overload-mediated therapy. Moreover, it is found that the generation of hyperthermia and oxidative stress from Cu2O@CaCO3 nanocomposites can efficiently reprogram the macrophages from the M2 phenotype to the M1 phenotype and initiate a vaccine-like immune effect after primary tumor removal, which further induces an immune-favorable TME and intense immune responses for anti-CD47 antibody to simultaneously inhibit CRC distant metastasis and recurrence by immunotherapy. 相似文献
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层析成像技术在多相流检测中的应用 总被引:12,自引:0,他引:12
介绍了流动层析成像技术的一般概念。综述了X射线、γ射线、中子射线、超声波和电容等5大类流动层析成像技术的发展现状,最后论述了该项技术的发展趋势和工业应用前景。 相似文献
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小湾水电站左岸混凝土拌和系统布置在2#-4#山梁高边坡地段,场地狭窄,系统规模、设计难度大,本文结合场地条件,对系统的工艺设计流程、建筑物的布置、胶凝材料下送试验等进行了介绍,并对系统设计的难点、特点做了详细的论述,为以后类似的设计项目提供一些经验借鉴. 相似文献
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设计了一款用于高速图像传感器的可自调节、加速补偿CMOS电荷泵锁相环电路,通过在传统锁相环电路拓扑中,附加"双模式"逻辑时控的、低功耗加速充电补偿模块,实现了锁定时间与功耗的双重优化.基于180 nm/1.8 V CMOS工艺完成锁相环的电路设计和性能仿真,结果表明,基于所提出的加速补偿方案,改进后的锁相环可有效满足图像传感器对低功耗、高速、高频和低噪声输出特性的需求.在输入频率为1 GHz的参考信号时,压控振荡器可达到0.55~2.82 GHz,即2.27 GHz的频率范围,相位噪声为-98.149 dBc/Hz@1 MHz,锁定时间缩短至5.2μs,整体功耗仅为1.98 mW,同时输出的抖动噪声可低至2.81 μV/√Hz@1 MHz,多个性能指标优于所对比的同类锁相环电路. 相似文献
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Multicast transfer can efficiently save the bandwidth consumption and reduce the load on the source node than a series of independent unicast transfers.Nowadays,many applications employ the content replica strategy to improve the robustness and efficiency;hence each file and its replicas are usually distributed among multiple sources.In such scenarios,the traditional deterministic multicast develops into the Uncertain multicast,which has more flexibility in the source selection.In this paper,we focus on building and maintaining a minimal cost forest(MCF)for any uncertain multicast,whose group members(source nodes and destination nodes)may join or leave after constructing a MCF.We formulate this dynamic minimal cost forest(DMCF)problem as a mixed integer programming model.We then design three dedicated methods to approximate the optimal solution.Among them,our a-MCF aims to efficiently construct an MCF for any given uncertain multicast,without dynamic behaviors of multicast group members.The d-MCF method motivates to slightly update the existing MCF via local modifications once appearing a dynamic behavior.It can achieve the balance between the minimal cost and the minimal modifications to the existing forest.The last r-MCF is a supplement method to the d-MCF method,since many rounds of local modifications maymake the resultant forest far away from the optimal forest.Accordingly,our r-MCF method monitors the accumulated degradation and triggers the rearrangement process to reconstruct an new MCF when necessary.The comprehensive evaluation results demonstrate that our methods can well tackle the proposed DMCF problem. 相似文献