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181.
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Evaporation‐ and Solution‐Process‐Feasible Highly Efficient Thianthrene‐9,9′,10,10′‐Tetraoxide‐Based Thermally Activated Delayed Fluorescence Emitters with Reduced Efficiency Roll‐Off 下载免费PDF全文
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High‐Performance Polymer Tandem Solar Cells Employing a New n‐Type Conjugated Polymer as an Interconnecting Layer 下载免费PDF全文
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Xiaoshuai Li Zhengwei Yuan Xiaowei Wei Hui Li Guifeng Zhao Jiaoning Miao Di Wu Bo Liu Songying Cao Dong An Wei Ma Henan Zhang Weilin Wang Qiushi Wang Hui Gu 《Journal of materials science. Materials in medicine》2016,27(4):77
Spina bifida aperta are complex congenital malformations resulting from failure of fusion in the spinal neural tube during embryogenesis. Despite surgical repair of the defect, most patients who survive with spina bifida aperta have a multiple system handicap due to neuron deficiency of the defective spinal cord. Tissue engineering has emerged as a novel treatment for replacement of lost tissue. This study evaluated the prenatal surgical approach of transplanting a chitosan–gelatin scaffold seeded with bone marrow mesenchymal stem cells (BMSCs) in the healing the defective spinal cord of rat fetuses with retinoic acid induced spina bifida aperta. Scaffold characterisation revealed the porous structure, organic and amorphous content. This biomaterial promoted the adhesion, spreading and in vitro viability of the BMSCs. After transplantation of the scaffold combined with BMSCs, the defective region of spinal cord in rat fetuses with spina bifida aperta at E20 decreased obviously under stereomicroscopy, and the skin defect almost closed in many fetuses. The transplanted BMSCs in chitosan–gelatin scaffold survived, grew and expressed markers of neural stem cells and neurons in the defective spinal cord. In addition, the biomaterial presented high biocompatibility and slow biodegradation in vivo. In conclusion, prenatal transplantation of the scaffold combined with BMSCs could treat spinal cord defect in fetuses with spina bifida aperta by the regeneration of neurons and repairmen of defective region. 相似文献
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Zi-Jie Rong Lian-Jun Yang Bao-Ta Cai Li-Xin Zhu Yan-Lin Cao Guo-Feng Wu Zan-Jie Zhang 《Journal of materials science. Materials in medicine》2016,27(5):89
To develop adriamycin (ADM)-encapsulated poly(lactic-co-glycolic acid) (PLGA) nanoparticles in a porous nano-hydroxyapatite/collagen scaffold (ADM–PLGA–NHAC). To provide novel strategies for future treatment of osteosarcoma, the properties of the scaffold, including its in vitro extended-release properties, the inhibition effects of ADM–PLGA–NHAC on the osteosarcoma MG63 cells, and its bone repair capacity, were investigated in vivo and in vitro. The PLGA copolymer was utilized as a drug carrier to deliver ADM–PLGA nanoparticles (ADM–PLGA–NP). Porous nano-hydroxyapatite and collagen were used to materials to produce the porous nano-hydroxyapatite/collagen scaffold (NHAC), into which the ADM–PLGA–NP was loaded. The performance of the drug-carrying scaffold was assessed using multiple techniques, including scanning electron microscopy and in vitro extended release. The antineoplastic activities of scaffold extracts on the human osteosarcoma MG63 cell line were evaluated in vitro using the cell counting kit-8 (CCK8) method and live-dead cell staining. The bone repair ability of the scaffold was assessed based on the establishment of a femoral condyle defect model in rabbits. ADM–PLGA–NHAC and NHAC were implanted into the rat muscle bag for immune response experiments. A tumor-bearing nude mice model was created, and the TUNEL and HE staining results were observed under optical microscopy to evaluate the antineoplastic activity and toxic side effects of the scaffold. The composite scaffold demonstrated extraordinary extended-release properties, and its extracts also exhibited significant inhibition of the growth of osteosarcoma MG63 cells. In the bone repair experiment, no significant difference was observed between ADM–PLGA–NHAC and NHAC by itself. In the immune response experiments, ADM–PLGA–NHAC exhibited remarkable biocompatibility. The in vivo antitumor experiment revealed that the implantation of ADM–PLGA–NHAC in the tumor resulted in a improved antineoplastic effect and fewer adverse side effects than direct intraperitoneal injection of ADM. The ADM–PLGA–NHAC developed in this study exhibited excellent extended-release drug properties, bone repairing and antineoplastic efficacy, which make it a promising osteoconductivity material with the capability to inhibit osteosarcoma. 相似文献
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基于DUBBO+ZOOKEEPER的计量服务平台是互联网与传统计量检测服务业相结合的产物,平台系统设计充分考虑了计量行业特点,在此基础上确定系统的建设目标,重点解决分布式系统集群中数据共享、数据一致性与服务水平扩展等问题。系统遵循JF1069-2012、JJF1033-2014、GB/T19022.1、ISO10012-1、ISO9000和ISO/IEC17025等规范,使用JAVA语言和众多开源框架,融入先进的管理理念,对涉及涵盖政府、计量技术机构、企事业单位、高校各个部门计量行业的工作程序进行全面的规范和整合,实现以服务为中心,对计量资源人、才、物(标准、规范、检测业务、器具证书)等方面的科学管理,同时辅以决策支持和实时的智能化预警机制。构建计量管理知识资源化、数字化具有十分重要的现实意义和应用价值。 相似文献
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Polyethylene Glycol–CaCl2 Coordination Compounds as a Novel Form‐Stable Phase Change Material with Excellent Thermophysical Properties 下载免费PDF全文
Qinrong Sun Haiquan Zhang Yanping Yuan Xiaoling Cao Liangliang Sun 《Advanced Engineering Materials》2018,20(3)