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101.
仿生眼的研究现状与发展趋势   总被引:10,自引:2,他引:10  
邹海荣  龚振邦  罗均 《机器人》2005,27(5):469-474
首先,在分析人眼眼球运动的特点和形式的基础上,详细介绍了国内外仿生眼研究对扫视性眼球运动、平滑性眼球运动、异向眼球运动、前庭动眼反射、视动反射等的模仿,最后总结了仿生眼研究的特点和发展趋势.  相似文献   
102.
系统以工控机为中心,配以高性能的模块化外设组成一体化的计算机控制系统。采用温度控制外环和电流平衡控制内环的双环路结构来具体实现交流电弧炉温度和三相电流平衡的智能集成控制。外环采用模糊、神经网络和优化决策共同控制,内环则采用模糊专家解耦控制。系统能实时自适应炉况状态的变化,提高生产效率,降低电能及电极消耗。实际运行证明该系统具有良好的鲁棒性和实时性。  相似文献   
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Circular RNAs (circRNAs), a class of new endogenous non-coding RNAs (ncRNAs), are closely related to the carcinogenic process and play a critical role in tumor metastasis. CircRNAs can lay the foundation for tumor metastasis via promoting tumor angiogenesis, make tumor cells gain the ability of migration and invasion by regulating epithelial-mesenchymal transition (EMT), interact with immune cells, cytokines, chemokines, and other non-cellular components in the tumor microenvironment, damage the normal immune function or escape the immunosuppressive network, and further promote cell survival and metastasis. Herein, based on the characteristics and biological functions of circRNA, we elaborated on the effect of circRNA via circRNA-associated competing endogenous RNA (ceRNA) network by acting as miRNA/isomiR sponges on tumor angiogenesis, cancer cell migration and invasion, and interaction with the tumor microenvironment (TME), then explored the potential interactions across different RNAs, and finally discussed the potential clinical value and application as a promising biomarker. These results provide a theoretical basis for the further application of metastasis-related circRNAs in cancer treatment. In summary, we briefly summarize the diverse roles of a circRNA-associated ceRNA network in cancer metastasis and the potential clinical application, especially the interaction of circRNA and miRNA/isomiR, which may complicate the RNA regulatory network and which will contribute to a novel insight into circRNA in the future.  相似文献   
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Adipocyte iron overload is a maladaptation associated with obesity and insulin resistance. The objective of the current study was to determine whether and how adipose tissue macrophages (ATMs) regulate adipocyte iron concentrations and whether this is impacted by obesity. Using bone marrow-derived macrophages (BMDMs) polarized to M0, M1, M2, or metabolically activated (MMe) phenotypes, we showed that MMe BMDMs and ATMs from obese mice have reduced expression of several iron-related proteins. Furthermore, the bioenergetic response to iron in obese ATMs was hampered. ATMs from iron-injected lean mice increased their glycolytic and respiratory capacities, thus maintaining metabolic flexibility, while ATMs from obese mice did not. Using an isotope-based system, we found that iron exchange between BMDMs and adipocytes was regulated by macrophage phenotype. At the end of the co-culture, MMe macrophages transferred and received more iron from adipocytes than M0, M1, and M2 macrophages. This culminated in a decrease in total iron in MMe macrophages and an increase in total iron in adipocytes compared with M2 macrophages. Taken together, in the MMe condition, the redistribution of iron is biased toward macrophage iron deficiency and simultaneous adipocyte iron overload. These data suggest that obesity changes the communication of iron between adipocytes and macrophages and that rectifying this iron communication channel may be a novel therapeutic target to alleviate insulin resistance.  相似文献   
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本文在现有网络分析的基础上,进行了EDGE数据网的规划,并通过仿真对规划结果进行了验证,最后对语音和数据网络的资源配置方法进行了研究,提出了相应的资源配置方法。  相似文献   
109.
Invariant natural killer T (iNKT) cells have the capacity to mount potent anti-tumor reactivity and have therefore become a focus in the development of cell-based immunotherapy. iNKT cells attack tumor cells using multiple mechanisms with a high efficacy; however, their clinical application has been limited because of their low numbers in cancer patients and difficulties in infiltrating solid tumors. In this study, we aimed to overcome these critical limitations by using α-GalCer, a synthetic glycolipid ligand specifically activating iNKT cells, to recruit iNKT to solid tumors. By adoptively transferring human iNKT cells into tumor-bearing humanized NSG mice and administering a single dose of tumor-localized α-GalCer, we demonstrated the rapid recruitment of human iNKT cells into solid tumors in as little as one day and a significantly enhanced tumor killing ability. Using firefly luciferase-labeled iNKT cells, we monitored the tissue biodistribution and pharmacokinetics/pharmacodynamics (PK/PD) of human iNKT cells in tumor-bearing NSG mice. Collectively, these preclinical studies demonstrate the promise of an αGC-driven iNKT cell-based immunotherapy to target solid tumors with higher efficacy and precision.  相似文献   
110.
本文介绍了以图像传感器OV6630、CPLD和C8051F单片机等为核心的图像采集系统,通过实验验证了在CPLD与C8051F单片机接口间存在的信号抖动问题.针对这一问题,根据微分电路原理.采用Verilog-HDL语言设计了去抖动模块,解决了图像采集系统的图像失真问题.  相似文献   
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