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101.
A novel drug-loaded pathogen-mimicking nanocomplex (MSN-DOX-SP-LPS) has been constructed for synergistic chemo-immunotherapy.
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102.
Here we develop a strategy using near infrared (NIR) modulation of telomerase activity based on gold nanocage@smart polymer system. Using this biocompatible design, we can regulate cellular behavior. This system has been used in vivo by taking advantages of NIR. This is the first example for optical modulation of telomerase activity in living cells and tissues.
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Responsive nanomaterials have emerged as promising candidates as drug delivery vehicles in order to address biomedical diseases such as cancer. In this work, polymer‐based responsive nanoparticles prepared by a supramolecular approach are loaded with doxorubicin (DOX) for the cancer therapy. The nanoparticles contain disulfide bonds within the polymer network, allowing the release of the DOX payload in a reducing environment within the endoplasm of cancer cells. In addition, the loaded drug can also be released under acidic environment. In vitro anticancer studies using redox and pH dual responsive nanoparticles show excellent performance in inducing cell death and apoptosis. Zebrafish larvae treated with DOX‐loaded nanoparticles exhibit an improved viability as compared with the cases treated with free DOX by the end of a 3 d treatment. Confocal imaging is utilized to provide the daily assessment of tumor size on zebrafish larva models treated with DOX‐loaded nanoparticles, presenting sustainable reduction of tumor. This work demonstrates the development of functional nanoparticles with dual responsive properties for both in vitro and in vivo drug delivery in the cancer therapy.  相似文献   
105.
Zinc oxide nanoparticles (ZnO NPs),as a new type of pH-sensitive drug carrier,have received much attention.ZnO NPs are stable at physiological pH,but can dissolve quickly in the acidic tumor environment (pH < 6) to generate cytotoxic zinc ions and reactive oxygen species (ROS).However,the protein corona usually causes the non-specific degradation of ZnO NPs,which has limited their application considerably.Herein,a new type of pH-sensitive nanoreactor (ZnO-DOX@F-mSiO2-FA),aimed at reducing the non-specific degradation of ZnO NPs,is presented.In the acidic tumor environment (pH < 6),it can release cytotoxic zinc ions,ROS,and anticancer drugs to kill cancer cells effectively.In addition,the fluorescence emitted from fluorescein isothiocyanate (FITC)-labeled mesoporous silica (F-mSiO2) and doxorubicin (DOX) can be used to monitor the release behavior of the anticancer drug.This report provides a new method to avoid the non-specific degradation of ZnO NPs,resulting in synergetic therapy by taking advantage of ZnO NPs-induced oxidative stress and targeted drug release.  相似文献   
106.
Because of cost and time limitations, reliability experiments frequently contain subsampling, which is a restriction on randomization. A two‐stage approach can analyze right censored Weibull distributed reliability data with subsampling. However, in implementing such a method, we found that it did not address the problems of how to perform confidence intervals of low percentiles and reduce the bias of estimates. In this paper, we present a two‐stage bootstrapping approach and an unbiasing factor approach to solve the aforementioned problems. An example is provided to illustrate the proposed method. In addition, the proposed method is compared with existing methods through simulation. The resulting simulations show that the proposed method performs well in low percentiles. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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In this work, the nucleation crystallography of CrFeNb intermetallic particles as a grain refiner for Ni‐based IN718 superalloys is studied using Edge‐to‐Edge Matching model. Three distinguishable orientation relationships between CrFeNb intermetallic particles and Ni grains are well predicted: , (111)Ni 1.28° from (0004)CrFeNb, , (111)Ni 1.32° from CrFeNb, and Ni//[0001]CrFeNb, (111)Ni 0.72° from CrFeNb. The results indicate that CrFeNb intermetallic particles have a strong nucleation potency as an effective grain refiner for Ni‐based superalloy and the existence of semi‐coherent interfaces between the CrFeNb intermetallic particles and Ni grains. Furthermore, the IN718 superalloy is used to experimentally validate the grain refinement effect of CrFeNb intermetallic particles, showing that its grain size is obviously refined from 8.60 to 1.23 mm. And, the corresponding heterogeneous nucleation mechanism of grain refinement at the atomic level is further identified.
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110.
Converting ubiquitous environmental energy into electric power holds tremendous social and financial interests. Traditional energy harvesters and converters are limited by the specific materials and complex configuration of devices. Herein, it is presented that electric power can be directly produced from pristine graphene oxide (GO) without any pretreatment or additives once encountering the water vapor, which will generate an open‐circuit‐voltage of up to 0.4–0.7 V and a short‐circuit‐current‐density of 2–25 µA cm?2 on a single piece of GO film. This phenomenon results from the directional movement of charged hydrogen ions through the GO film. The present work demonstrates and provides an extremely simple method for electric energy generation, which offers more applications of graphene‐based materials in green energy converting field.  相似文献   
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