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991.
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Graphene substrates promote adherence of human osteoblasts and mesenchymal stromal cells 总被引:1,自引:0,他引:1
The biocompatibility of large single layer graphene produced by chemical vapour deposition was investigated using human osteoblasts and mesenchymal stromal cells. The study was focused on cellular adhesion, morphology and the ability to proliferate on graphene substrates. It was found that both of the cell types which were tested adhered and proliferated better when cultured on graphene films than on a SiO2 substrate. 相似文献
994.
基于龙芯3A处理器的tPMON设计与实现 总被引:1,自引:0,他引:1
龙芯处理器在军用计算机系统广泛应用的同时,对安全性要求更为苛刻。在充分考虑嵌入式系统的特点及设计的约束基础上,借鉴可信计算的思想,首先对PMON和安全哈希算法(Secure Hash Algorithm,SHA-1)作了简单介绍,然后讨论了虚拟可信平台模块(virtual Trusted Platform Module,vTPM)的实现方法,最后给出了基于龙芯3A处理器的可信PMON(tPMON)的具体实现方案。实验结果表明,虽然tPMON的启动时间增加了,但是该方案在不增加额外硬件的基础上,使系统的安全性得到了很大提高。 相似文献
995.
激光超声光学检测应用 总被引:1,自引:0,他引:1
激光脉冲照射样品表面会发出超声波,利用光学方法对超声波进行检测,可以对材料和产品质量进行无损评估。介绍了激光超声共焦法布里-珀罗(F-P)检测的原理,设计了一种新型共焦F-P干涉检测仪(CFPI),很好地解决了激光超声光检测中激光器的稳定问题和CFPI的稳定问题,用纯光学方法实现了真正意义上的无损检测应用,实验验证了该激光超声光学检测系统的实现方式。 相似文献
996.
Catalysis Letters - For the noble-metal based catalysts, the metal dispersion and sinter resistance of the metal nanoparticles (NPs) are the most vital factors for their application in series... 相似文献
997.
Cong-Xu Zhu Han-Lu Zhang Wen-Jun Fa Feng-Wei Mian Xiang-Qing Kong Chun-Sheng Kong Ming-Hua Feng Yu Wang Wei-Wei Li Zhen-Li Huang Zhi Zheng 《稀有金属(英文版)》2021,(8):2292-2300
As a kind of rare materials,nano-silver has broad application prospects in the fields of catalysis,medical treatment,new energy and so on.However,there are few ... 相似文献
998.
999.
Cheng-Cheng Wang Jing-Ya Kong Chang-Hu Xue Tian-Tian Zhang Yu-Ming Wang 《Molecular nutrition & food research》2023,67(8):2200825
Blood−brain barrier (BBB) impairment is related to the development of Alzheimer's disease (AD), which is dependent not only on tight junction but also on transcytosis of brain endothelial cells (BECs) in the BBB. Aging induces the decrease of ligand-specific receptor-mediated transcytosis (RMT) and the increase of non-specific caveolar transcytosis in BECs, which lead to the entry into parenchyma of neurotoxic proteins and the smaller therapeutic index in central nervous system drug delivery, further provoking neurodegenerative disease. A previous study suggests that sea-derived Antarctic krill oil (AKO) exhibits synergistic effects with land-derived nobiletin (NOB) and theanine (THE) on ameliorating memory and cognitive deficiency in SAMP8 mice. However, it is still unclear whether BBB change is involved. Hence, the effects of AKO combined with NOB and THE on aging-induced BBB impairment, including tight junction between BECs, ligand-specific RMT, and non-specific caveolar transcytosis in BECs, are investigated. The results suggest that AKO exhibits synergistic effects with NOB and THE on regulating ligand-specific RMT in BBB by inhibiting alkaline phosphatase (ALPL). The study provides a potential strategy candidate or targeted dietary patterns to prevent and treat AD by improving the BBB function. 相似文献
1000.
Zhiwen Zheng Xiaotong Zheng Degang Kong Kai Ding Zhao Zhang Run Zhong Jing He Shaobing Zhou 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(24):2207252
The abnormal pressure in tumor tissue is a significant limitation on the drug delivery efficiency of tumor therapy. This work reports a gradient-driven nanomotor as drug nanocarrier with the pressure-counterworking function. The dual-fuel nanomotors are formed by co-electrospinning of the photosensitive polymers with calcium peroxide (CaO2) and catalase (CAT), followed by ultraviolet (UV) irradiation and bovine serum albumin (BSA) incubation. The UV-responsive cleavage nanomotors can effectively release O2 molecules at the fractures as a driving force to increase the delivery speed and escape the phagocytosis of macrophage system in normal tissues. Furthermore, CAT catalyzes H2O2 produced by CaO2 and the tumor interstitial fluids to provide stronger power for the nanomotors. Additionally, according to the analysis of directional motions of the nanomotors, the functional relationship between the rotational diffusion coefficient (DR) and the physiological viscosity is constructed. The dual-fuel nanocarriers enable up to 13.25% of the injected dose (ID)/per gram tissue and significantly improve the penetration in deep tumor. It is of vital importance to design and obtain the adaptive pressure-gradient counterworking nanomotors, which can effectively improve the drug delivery efficiency in vitro and in vivo. 相似文献