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21.
以往智能终端机只是利用于卷烟销售方面,用于专卖工作的还不曾提及,是行业的盲点。基于3G网络的专卖移动办公平台以IMS为网络基础,以J2EE与J2ME为技术架构,使用成熟的中间件和可复用的业务组件实现了系统的跨平台性、伸缩性、可移植性和可维护性,为"卷烟上水平"提供有力的市场保障。 相似文献
22.
Jiajia Deng Xin Wang Weihua Zhang Liangyan Sun Xinxin Han Xianqin Tong Liming Yu Jiandong Ding Lin Yu Yuehua Liu 《Advanced functional materials》2023,33(21):2211664
Extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) have emerged as an appealing alternative to cell therapy in regenerative medicine. Unlike bone marrow MSCs (BMSCs) cultured in vitro with normoxia, bone marrow in vivo is exposed to a hypoxic environment. To date, it remains unclear whether hypoxia preconditioning can improve the function of BMSC-derived EVs and be more conducive to bone repair. Herein, it is found that hypoxia preconditioned BMSCs secrete more biglycan (Bgn)-rich EVs via proteomics analysis, and these hypoxic EVs (Hypo-EVs) significantly promote osteoblast proliferation, migration, differentiation, and mineralization by activating the phosphatidylinositide 3-kinase/protein kinase B pathway. Subsequently, an injectable bioactive hydrogel composed of poly(ethylene glycol)/polypeptide copolymers is developed to improve the stability and retention of Hypo-EVs in vivo. The Hypo-EVs-laden hydrogel shows continuous liberation of Hypo-EVs for 3 weeks and substantially accelerates bone regeneration in 5-mm rat cranial defects. Finally, it is confirmed that Bgn in EVs is a pivotal protein regulating osteoblast differentiation and mineralization and exerts its effects through paracrine mechanisms. Therefore, this study shows that hypoxia stimulation is an effective approach to optimize the therapeutic effects of BMSC-derived EVs and that injectable hydrogel-based EVs delivery is a promising strategy for tissue regeneration. 相似文献
23.
Ruiqi Li Lian Chen Qin Ji Qing Liang Ying Zhu Wei Fu Tianyou Chen Hongwei Duan Wenshan He Zushun Xu Xiaofang Dai Jinghua Ren 《Advanced functional materials》2023,33(37):2213292
Radiotherapy is identified as a crucial treatment for patients with glioblastoma, but recurrence is inevitable. The efficacy of radiotherapy is severely hampered partially due to the tumor evolution. Growing evidence suggests that proneural glioma stem cells can acquire mesenchymal features coupled with increased radioresistance. Thus, a better understanding of mechanisms underlying tumor subclonal evolution may develop new strategies. Herein, data highlighting a positive correlation between the accumulation of macrophage in the glioblastoma microenvironment after irradiation and mesenchymal transdifferentiation in glioblastoma are presented. Mechanistically, elevated production of inflammatory cytokines released by macrophages promotes mesenchymal transition in an NF-κB-dependent manner. Hence, rationally designed macrophage membrane-coated porous mesoporous silica nanoparticles (MMNs) in which therapeutic anti-NF-κB peptides are loaded for enhancing radiotherapy of glioblastoma are constructed. The combination of MMNs and fractionated irradiation results in the blockage of tumor evolution and therapy resistance in glioblastoma-bearing mice. Intriguingly, the macrophage invasion across the blood-brain barrier is inhibited competitively by MMNs, suggesting that these nanoparticles can fundamentally halt the evolution of radioresistant clones. Taken together, the biomimetic MMNs represent a promising strategy that prevents mesenchymal transition and improves therapeutic response to irradiation as well as overall survival in patients with glioblastoma. 相似文献
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25.
Spatial Micropatterning of Growth Factors in 3D Hydrogels for Location‐Specific Regulation of Cellular Behaviors 下载免费PDF全文
Growth factors are potent stimuli for regulating cell function in tissue engineering strategies, but spatially patterning their presentation in 3D in a facile manner using a single material is challenging. Micropatterning is an attractive tool to modulate the cellular microenvironment with various biochemical and physical cues and study their effects on stem cell behaviors. Implementing heparin's ability to immobilize growth factors, dual‐crosslinkable alginate hydrogels are micropatterned in 3D with photocrosslinkable heparin substrates with various geometries and micropattern sizes, and their capability to establish 3D micropatterns of growth factors within the hydrogels is confirmed. This 3D micropatterning method could be applied to various heparin binding growth factors, such as fibroblast growth factor‐2, vascular endothelial growth factor, transforming growth factor‐betas and bone morphogenetic proteins while retaining the hydrogel's natural degradability and cytocompability. Stem cells encapsulated within these micropatterned hydrogels have exhibited spatially localized growth and differentiation responses corresponding to various growth factor patterns, demonstrating the versatility of the approach in controlling stem cell behavior for tissue engineering and regenerative medicine applications. 相似文献
26.
To improve in-vocabulary performance in Mongolian speech keyword spotting task, we propose a Mongolian speech keyword spotting method by searching the stem according to the characteristic of Mongolian word-formation rule. First, Mongolian speech is decoded to lattice file by Segmentation-based LVCSR system, and this lattice file is converted to a confusion network. Then, we detect the keywords according to their stems among the confusion network. Experimental results show that the proposed method outperforms baselines based on word confusion network. 相似文献
27.
归纳了当前在科研和应用领域中的热门课题———虚拟现实技术的含义、“3I”特征及应用形式。提出了虚拟现实技术在现代测控系统中应用研究的实现框架。在此基础上着重讨论了虚拟现实的VRML97的实现。最后进一步展望了该技术在测控领域的发展前景。 相似文献
28.
刘自毫 《艺术与设计.数码设计》2007,(3)
本文以《烟草控制框架公约》在我国正式生效后,按照《公约》对卷烟包装的规定,我国的卷烟商标和包装在很大程度上要重新设计和制作为着眼点,从正确履行《烟草控制框架公约》保持中式卷烟包装设计特色、正确理解中式卷烟内涵,明确烟标和包装设计方向、中式卷烟包装和色彩与消费心理有着密切的关系以及中式卷烟包装应该提高环保意识、减少环境污染和中式卷烟包装应提高技术含量,利用核心技术进行防伪设计等方面,论述了中式卷烟包装设计的发展方向及注意的事项。 相似文献
29.
bFGF促增殖后骨髓间充质干细胞向多巴胺能神经元样细胞的分化 总被引:4,自引:0,他引:4
目的探讨碱性成纤维细胞生长因子(Basic fibroblast growth factor,bFGF)体外作用于骨髓间充质干细胞(Mesen-chymal stem cells,MSCs)后,诱导其向神经元样细胞和多巴胺能神经元样细胞定向分化的情况。方法从鼠骨髓中获得MSCs,培养传代,用MTT法检测bFGF对骨髓MSCs生长的影响。10 ng/ml bFGF作用2 d后,通过IBMX、细胞因子bFGF、GDNFI、L-1β、中脑神经胶质细胞条件培养基和中脑神经细胞膜碎片等分组联合诱导骨髓MSCs向神经元样细胞、多巴胺能神经元样细胞分化,免疫细胞化学方法鉴定特异标志NSE、MAP-2a,b和TH的表达。结果在一定范围内,bFGF对骨髓MSCs具有明显的促增殖作用。分化的神经元样细胞表达NSE、MAP-2a,b和TH,联合应用GDNFI、L-1β、中脑条件培养基和中脑神经细胞膜碎片诱导7 d后,NSE阳性率为(27.774±2.747)%,MAP-2a,b为(28.006±3.080)%,TH为(3.098±0.352)%。结论体外骨髓MSCs被诱导分化成神经元样细胞和多巴胺能神经元样细胞,为帕金森等中枢神经系统疾病的细胞移植治疗奠定了基础。 相似文献
30.
目的探讨脑干梗死经DSA全脑血管造影证实基底动脉闭塞后的临床与预后,以期对临床治疗有一定的指导意义。方法选取14例在临床中发现并经脑血管造影证实为基底动脉闭塞而临床症状轻微的患者。分析基底动脉闭塞后的临床表现与侧支代偿之间的关系。结果(1)基底动脉近端闭塞,临床表现多以眩晕发作为主(占91%);中段或远端闭塞,则多表现为间断性意识障碍(占66.7%)。(2)基底动脉近端闭塞,侧支血流多由颈外动脉和锁骨下动脉分支及椎动脉颅外段的肌支或脊髓前动脉代偿供血;基底动脉中、远段闭塞,侧支血流多由小脑后下动脉与小脑上动脉吻合(占100%)。结论基底动脉闭塞若侧支代偿充分,可不表现明显的脑干缺血表现或表现轻微。内科治疗效果较好。 相似文献