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排序方式: 共有9419条查询结果,搜索用时 15 毫秒
41.
Hydrogels, a class of materials with a 3D network structure, are widely used in various fields especially in biomedicine. Injectable hydrogels could facilitate the encapsulation and controlled release of small molecular drugs, macromolecular therapeutics, and even cells. With the rapid development of cancer immunotherapy, such injectable hydrogels have attracted wide attention for local immunomodulation to boost systemic anticancer immune responses, realizing more effective immunotherapy at lower doses. The latest progresses in the development of various smart injectable hydrogels for cancer immunotherapy are summarized here. Although applied locally, such injectable hydrogels can activate systemic antitumor immune responses, safely and effectively inhibiting the tumor metastasis and recurrence. Moreover, it is discussed how injectable hydrogel‐based cancer immunotherapy would contribute to the development of next generation of cancer treatment together with their potential for clinical translation. 相似文献
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Jingjing Liu Min Wu Yutong Pan Yukun Duan Ziliang Dong Yu Chao Zhuang Liu Bin Liu 《Advanced functional materials》2020,30(13)
Nowadays various inorganic nanoparticles that generate highly reactive hydroxyl radical ( · OH) on the basis of Fenton‐like catalytic activity of metal ions have been designed for chemodynamic therapy. However, the high level of adaptive antioxidants [glutathione (GSH)] in cancer cells could effectively consume · OH to compromise the treatment efficiency and biosafety of these inorganic nanoparticles, and this is a general concern in chemodynamic therapy. Herein, a new biodegradable nanoscale coordination polymer (NCP) is developed by integration of cisplatin prodrug (DSCP) and iron (III) ions through a reverse microemulsion method. The DSCP in the NCPs could react with GSH to release free cisplatin, while the iron (III) ions could be reduced by GSH into iron (II) to enable Fenton reaction, subsequently leading to amplified intracellular oxidative stress. After surface modification of polyethylene glycol (PEG) and cyclo[Arg‐Gly‐Asp‐D‐Phe‐Lys(mpa)] peptide (cRGD), Fe‐DSCP‐PEG‐cRGD shows an excellent targeting effect against αvβ3‐integrin overexpressed tumor cells. Furthermore, Fe‐DSCP‐PEG‐cRGD enables significant chemo and chemodynamic therapy with dramatically enhanced therapeutic efficiency in comparison to relative monotherapies. Importantly, Fe‐DSCP‐PEG‐cRGD could be efficiently cleared out from mice through feces and urine postinjection 7 days. The NCP presented in this work is simple and economical, which shows great biodegradability and biosafety for potential clinical translation. 相似文献
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高冲突证据下的目标识别方法研究一直是热点和难点问题。比例冲突再分配规则正是处理高冲突证据的一种有效方法。介绍并分析了比例冲突再分配系列规则,并通过具体的例子对不同方法进行了仿真验证,说明了比例冲突再分配规则能很好地处理目标识别问题中的高冲突证据。 相似文献
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对动态云平台电子证据存储代表的必要性的研究,证明所有资源网站的可信任性是安全云平台电子证据存储计算的一个先决条件.分析了现有的代表团类和电网计划,并提出了云平台电子证据存储访问控制的模糊信任、委托模型(FTDM)和基于云平台电子证据存储实体之间信任关系的两个阶段的模糊推理过程,进而决定类的代表团和信任级别授权访问的可能性.并且引用数字取证分析云平台资源的K-means聚类算法的基础上的CGRS资源选择算法,并在实务部门数字取证分析平台的可扩展环境中实施.通过分析和实验结果验证了分析平台的资源选择算法的有效性和正确性. 相似文献
46.
The ad hoc networks are completely autonomous wireless networks where all the users are mobile. These networks do not work on any infrastructure and the mobiles communicate either directly or via other nodes of the network by establishing routes. These routes are prone to frequent ruptures because of nodes mobility. If the future movement of the mobile can be predicted in a precise way, the resources reservation can be made before be asked, which enables the network to provide a better QoS. In this aim, we propose a virtual dynamic topology, which on one hand, will organize the network as well as possible and decreases the impact of mobility, and on the other hand, is oriented user mobility prediction. Our prediction scheme uses the evidence theory of Dempster–Shafer in order to predict the future position of the mobile by basing itself on relevant criteria. These ones are related to mobility and network operation optimisation. The proposed scheme is flexible and can be extended to a general framework. To show the relevance of our scheme, we combine it with a routing protocol. Then, we implemented the prediction-oriented topology and the prediction scheme which performs on it. We implemented also a mobility prediction based routing protocol. Simulations are made according to a set of elaborate scenarios. 相似文献
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针对信息检索隐式多样化算法展开研究。介绍了检索结果重排序中的最大边际相关度(MMR)算法、相对熵(KL)算法、现代投资组合理论(MPT)3个隐式多样化算法,采用此3个算法对所选的已排序的文档数据集进行重排,通过对排序结果进行评价来对比三者的性能。得出隐式多样化方法中当相关性和多样性以一定比例的线性组合时,会使最终的检索结果在一些评价指标上相对于原始结果有所提高。 相似文献
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介绍了ERP系统的设计特点,详细阐述了ERP系统所带来的积极变化,并从文化冲突的角度上分析了ERP系统实施中遇到的阻力。为了解决该困难,文中初步提出了ERP系统管理软件与中国式管理思想相融合的假设。 相似文献