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791.
Cannabis use has been growing recently and it is legally consumed in many countries. Cannabis has a variety of phytochemicals including cannabinoids, which might impair the peripheral systems responses affecting inflammatory and immunological pathways. However, the exact signaling pathways that induce these effects need further understanding. The objective of this study is to investigate the serum proteomic profiling in patients diagnosed with cannabis use disorder (CUD) as compared with healthy control subjects. The novelty of our study is to highlight the differentially changes proteins in the serum of CUD patients. Certain proteins can be targeted in the future to attenuate the toxicological effects of cannabis. Blood samples were collected from 20 male individuals: 10 healthy controls and 10 CUD patients. An untargeted proteomic technique employing two-dimensional difference in gel electrophoresis coupled with mass spectrometry was employed in this study to assess the differentially expressed proteins. The proteomic analysis identified a total of 121 proteins that showed significant changes in protein expression between CUD patients (experimental group) and healthy individuals (control group). For instance, the serum expression of inactive tyrosine protein kinase PEAK1 and tumor necrosis factor alpha-induced protein 3 were increased in CUD group. In contrast, the serum expression of transthyretin and serotransferrin were reduced in CUD group. Among these proteins, 55 proteins were significantly upregulated and 66 proteins significantly downregulated in CUD patients as compared with healthy control group. Ingenuity pathway analysis (IPA) found that these differentially expressed proteins are linked to p38MAPK, interleukin 12 complex, nuclear factor-κB, and other signaling pathways. Our work indicates that the differentially expressed serum proteins between CUD and control groups are correlated to liver X receptor/retinoid X receptor (RXR), farnesoid X receptor/RXR activation, and acute phase response signaling.  相似文献   
792.
The mechanism behind the cytoprotective potential of cerium oxide nanoparticles (CeO2 NPs) against cytotoxic nitric oxide (NO) donors and H2O2 is still not clear. Synthesized and characterized CeO2 NPs significantly ameliorated the lipopolysaccharide (LPS)-induced cytokines IL-1β and TNF-α. The main goal of this study was to determine the capacities of NPs regarding signaling effects that could have occurred due to reactive oxygen species (ROS) and/or NO, since NP-induced ROS/NO did not lead to toxicity in HUVE cells. Concentrations that induced 50% cell death (i.e., IC50s) of two NO donors (DETA-NO; 1250 ± 110 µM and sodium nitroprusside (SNP); 950 ± 89 µM) along with the IC50 of H2O2 (120 ± 7 µM) were utilized to evaluate cytoprotective potential and its underlying mechanism. We determined total ROS (as a collective marker of hydrogen peroxide, superoxide radical (O2•−), hydroxyl radical, etc.) by DCFH-DA and used a O2•− specific probe DHE to decipher prominent ROS. The findings revealed that signaling effects mediated mainly by O2•− and/or NO are responsible for the amelioration of toxicity by CeO2 NPs at 100 µg/mL. The unaltered effect on mitochondrial membrane potential (MMP) due to NP exposure and, again, CeO2 NPs-mediated recovery in the loss of MMP due to exogenous NO donors and H2O2 suggested that NP-mediated O2•− production might be extra-mitochondrial. Data on activated glutathione reductase (GR) and unaffected glutathione peroxidase (GPx) activities partially explain the mechanism behind the NP-induced gain in GSH and persistent cytoplasmic ROS. The promoted antioxidant capacity due to non-cytotoxic ROS and/or NO production, rather than inhibition, by CeO2 NP treatment may allow cells to develop the capacity to tolerate exogenously induced toxicity.  相似文献   
793.
在市场利率环境下,运用信号传递博弈理论,在成本倒挂情况下,采取利息补贴承诺的方法,设计一种以风险分担实现利润共享的契约机制,利润共享参数起到了传递信息的信号作用。研究结果表明,在该契约下企业没有撒谎的动机,契约参数是传达信息的信号。该契约机制下不仅可以实现信贷资金供求信息的共享,而且能够保证系统的协调,系统收益达到最优,使企业能够得到新产品生产所需资金,银行解决信贷资金的风险损失的问题。  相似文献   
794.
针对目前食品安全事件层出不穷的现状,本文利用信号博弈模型,讨论了“公司+农户”组织模式中导致农户发生机会主义行为的影响因素。通过对基本模型的分析,发现隐瞒生产信息所需要花费的粉饰成本是影响市场出现分离均衡或混同均衡的关键因素。通过对引入抽检后的扩展模型进行分析发现,如果外围市场处罚较小,并不能覆盖低质量农产品的利润与公司检验成本之和时,那么公司进行抽检的动力不大,或者即使抽检,市场中仍旧有违禁农产品的存在。最后讨论了在“公司+农户”模式中,如何提高农产品质量的方法和措施。  相似文献   
795.
为提升基于PIN电学结构载流子注入式硅基电光调制器性能, 采用TSMC 0.18μm CMOS工艺设计一种新型预加重驱动电路. 该电路采用电流模逻辑(CML)结构, 并引入低压差分信号(LVDS)型电流选择器, 在实现提升响应速度和工作带宽的同时, 降低整体平均功耗. 仿真结果表明: 基于PIN电学结构载流子注入式硅基电光调制器的电压响应时间同时受预加重驱动信号过冲幅度和持续时间影响. 当预加重驱动信号过冲幅度和持续时间分别取值为2V和0.2ns时, 基于PIN电学结构载流子注入式硅基电光调制器的电压响应时间缩减了16.7%, 工作带宽扩展至4.34倍, 且根据不同的开关活动性需求, 平均功耗最高降低了60%.  相似文献   
796.
The biosynthesis and signaling of plant hormones play a critical role in almost all biological processes. It is well-documented that phytohormones cross-talk with each other. Epigenetic mechanisms were suggested to regulate expression of downstream targets in hormone signaling pathways that help implement hormone functions. This new layer of complexities that integrate epigenetic information such as DNA methylation, chromatin remodeling, histone modification, microRNAs and siRNAs with plant hormone signaling and regulations of gene expression, has been gradually revealed. In this short review, the author tries to assemble recent progress to establish a molecular linkage between these two large and momentum research fields and also to help readers digest the literature.  相似文献   
797.
提出了一种基于信令机制的可扩展NSIS网络管理协议,定义了NSIS网络管理协议的服务原语及数据单元,以实现协议的主要通信过程及管理操作流程.利用Petri网对协议进行了形式化描述,并对协议的逻辑正确性和性能进行了验证分析.利用NS-2对整个协议进行了仿真.相关验证及仿真结果表明,基于NSIS的网络管理协议兼备IP的灵活性和信令的高效性,保障了管理信息的安全、可靠传输,能够满足基于IP承载的新一代多业务网络的管理需求.  相似文献   
798.
针对国阳二矿的应用需求,开发了一套"煤矿井下轨道运输管理自动化系统",详细介绍了该系统的组成和各部分功能,以及实际应用效果。  相似文献   
799.
介绍了汾河二坝枢纽工程的地质概况、地层岩性及物理力学性质指标,说明了清淤段淤积物的化学分析和击实试验,对河道淤积土层作为防洪堤加固所用土料的可行性进行了评价。  相似文献   
800.
基于FPGA的高速数据传输方案设计与实现   总被引:2,自引:0,他引:2  
为解决目前信号处理系统中数据传输的瓶颈问题,设计并实现了一种基于可编程门阵列(field programma-ble gate array,FPGA)的高速实时数据传输方案.该方案借助Xilinx FPGA的ChipSync技术,稳定地完成了数据的串化/解串,以及通信链路相对延迟的精确测量和调整.同时,利用提出的数据传输同步方法一系统同步和串行低压差分信号(low-voltage differential signaling,LVDS)总线技术实现板卡间大量数据的高速传送,有效地保证了多通道传输的同步性和可靠性,并大大降低了系统互联的复杂度和系统成本.  相似文献   
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