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Homeostatic regulation of brain functions by endocannabinoid signaling 被引量:1
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作者 Chu Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第5期691-692,共2页
Humans have been using Cannabis and its extracts for a few thousand years as a medicinal and recreational drug. How- ever, the chemical component in Cannabis sativa, △9-tet- rahydrocannabinol (△9-THC), an exogenou... Humans have been using Cannabis and its extracts for a few thousand years as a medicinal and recreational drug. How- ever, the chemical component in Cannabis sativa, △9-tet- rahydrocannabinol (△9-THC), an exogenous cannabinoid, remained unknown until it was isolated and identified as the main psychoactive ingredient (Gaoni and Mechoulam, 1964). 展开更多
关键词 CB Homeostatic regulation of brain functions by endocannabinoid signaling
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An improved empirical green function method to extract microseismic signals 被引量:1
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作者 Dayong Yu Pan Wang 《Geodesy and Geodynamics》 2019年第1期42-48,共7页
In mining, reservoir impoundment and hydraulic fracturing exploitation, the induced microseismic clusters may present complex waveforms at receivers since the individual events generally arrive very close. And the rou... In mining, reservoir impoundment and hydraulic fracturing exploitation, the induced microseismic clusters may present complex waveforms at receivers since the individual events generally arrive very close. And the routine methods for arrival picking are insufficiently efficient due to these strong influences. Here, we modified the empirical green function method and applied it to extract the green functions and the radiation coefficients of microseismic events with the largest energy in clusters.Multiple-channel records were used to estimate an "average" source spectrum and then the "average" source wavelet was removed from the records by deconvolution. We applied this method to the real data,and the result indicated clear improvement in extracting the dominant event of the clusters. 展开更多
关键词 Microseismic signalS Empirical green function SOURCE SPECTRA
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MiR-19a-3p regulates the Forkhead box F2-mediated Wnt/β-catenin signaling pathway and affects the biological functions of colorectal cancer cells 被引量:11
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作者 Fu-Bing Yu Juan Sheng +3 位作者 Jia-Man Yu Jing-Hua Liu Xiang-Xin Qin Bo Mou 《World Journal of Gastroenterology》 SCIE CAS 2020年第6期627-644,共18页
BACKGROUND Colorectal cancer(CRC)is one of the most common malignancies worldwide.AIM To explore the expression of microRNA miR-19a-3p and Forkhead box F2(FOXF2)in patients with CRC and the relevant mechanisms.METHODS... BACKGROUND Colorectal cancer(CRC)is one of the most common malignancies worldwide.AIM To explore the expression of microRNA miR-19a-3p and Forkhead box F2(FOXF2)in patients with CRC and the relevant mechanisms.METHODS Sixty-two CRC patients admitted to the hospital were enrolled into the study group,and sixty healthy people from the same period were assigned to the control group.Elbow venous blood was sampled from the patients and healthy individuals,and blood serum was saved for later analysis.MiR-19a-3p mimics,miR-19a-3p inhibitor,miR-negative control,small interfering-FOXF2,and short hairpin-FOXF2 were transfected into HT29 and HCT116 cells.Then quantitative polymerase chain reaction was performed to quantify the expression of miR-19a-3p and FOXF2 in HT29 and HCT116 cells,and western blot(WB)analysis was conducted to evaluate the levels of FOXF2,glycogen synthase kinase 3 beta(GSK-3β),phosphorylated GSK-3β(p-GSK-3β),β-catenin,p-β-catenin,α-catenin,Ncadherin,E-cadherin,and vimentin.The MTT,Transwell,and wound healing assays were applied to analyze cell proliferation,invasion,and migration,respectively,and the dual luciferase reporter assay was used to determine the correlation of miR-19a-3p with FOXF2.RESULTS The patients showed high serum levels of miR-19a-3p and low levels of FOXF2,and the area under the curves of miR-19a-3p and FOXF2 were larger than 0.8.MiR-19a-3p and FOXF2 were related to sex,tumor size,age,tumor-nodemetastasis staging,lymph node metastasis,and differentiation of CRC patients.Silencing of miR-19a-3p and overexpression of FOXF2 suppressed the epithelialmesenchymal transition,invasion,migration,and proliferation of cells.WB analysis revealed that silencing of miR-19a-3p and FOXF2 overexpression significantly suppressed the expression of p-GSK-3β,β-catenin,N-cadherin,and vimentin;and increased the levels of GSK-3β,p-β-catenin,α-catenin,and Ecadherin.The dual luciferase reporter assay confirmed that there was a targeted correlation of miR-19a-3p with FOXF2.In addition,a rescue experiment revealed that there were no differences in cell proliferation,invasion,and migration in HT29 and HCT116 cells co-transfected with miR-19a-3p-mimics+sh-FOXF2 and miR-19a-3p-inhibitor+si-FOXF2 compared to the miR-negative control group.CONCLUSION Inhibiting miR-19a-3p expression can upregulate the FOXF2-mediated Wnt/β-catenin signaling pathway,thereby affecting the epithelial-mesenchymal transition,proliferation,invasion,and migration of cells.Thus,miR-19a-3p is likely to be a therapeutic target in CRC. 展开更多
关键词 MiR-19a-3p Forkhead box F2 Wnt/β-catenin signaling pathway Biological function Colorectal cancer Western blot
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Modeling Distortion Signals of Power Grid Based on Wiener-G Functionals
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作者 Xiao-Bing Zhang Yun-Hui Li Guo-Zhi Fang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第3期79-84,共6页
The uniform mathematical model of distortion signals in power grid has been setup with the theory of Wiener-G Functional. Firstly,the Matlab simulation models were established. Secondly,the Wiener kernel of power load... The uniform mathematical model of distortion signals in power grid has been setup with the theory of Wiener-G Functional. Firstly,the Matlab simulation models were established. Secondly,the Wiener kernel of power load was found based on the Gaussian white noise as input. And then the uniform mathematical model of the power grid signal was established according to the homogeneous of the same order of Wiener functional series. Finally,taking three typical distortion sources which are semiconductor rectifier,electric locomotive and electric arc furnace in power grid as examples,we have validated the model through the Matlab simulation and analyzed the simulation errors. The results show that the uniform mathematical model of distortion signals in power grid can approximation the actual model by growing the items of the series under the condition of the enough storage space and computing speed. 展开更多
关键词 electric energy measurement distortion signals model of power grid signal functional series Wiener kernel
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TLR signaling that induces weak inflammatory response and SHIP1 enhances osteogenic functions 被引量:2
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作者 Manoj Muthukuru Richard P Darveau 《Bone Research》 SCIE CAS 2014年第4期218-230,共13页
Toll-like receptor (TLR)-mediated inflammatory response could negatively affect bone metabolism. In this study, we determined how osteogenesis is regulated during inflammatory responses that are downstream of TLR si... Toll-like receptor (TLR)-mediated inflammatory response could negatively affect bone metabolism. In this study, we determined how osteogenesis is regulated during inflammatory responses that are downstream of TLR signaling. Human primary osteoblasts were cultured in collagen gels. Pam3CSK4 (P3C) and Escherichia coli lipopolysaccharide (EcLPS) were used as TLR2 and TLR4 ligand respectively. Porphyromonas gingivalis LPS having TLR2 activity with either TLR4 agonism (Pg1690) or TLR4 antagonism (Pg1449) and mutant E. coli LPS (LPxE/LPxF/WSK) were used. IL-lp, SH2-containing inositol phosphatase-1 (SHIP1) that has regulatory roles in osteogenesis, alkaline phosphatase and mineralization were analyzed. 3α-Aminocholestane (3AC) was used to inhibit SHIP1. Our results suggest that osteoblasts stimulated by P3C, poorly induced IL-1β but strongly upregulated SHIP1 and enhanced osteogenic mediators. On the contrary, EcLPS significantly induced IL-1β and osteogenic mediators were not induced. While Pg1690 downmodulated osteogenic mediators, Pg1449 enhanced osteogenic responses, suggesting that TLR4 signaling annuls osteogenesis even with TLR2 activity. Interestingly, mutant E. coli LPS that induces weak inflammation upregulated osteogenesis, but SHIP1 was not induced. Moreover, inhibiting SHIP1 significantly upregulated TLR2-mediated inflammatory response and downmodulated osteogenesis. In conclusion, these results suggest that induction of weak inflammatory response through TLR2 (with SHIP1 activity) and mutant TLR4 ligands could enhance osteogenesis. 展开更多
关键词 TLR signaling that induces weak inflammatory response and SHIP1 enhances osteogenic functions SHIP FIGURE
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Kravchenko probabilityweight functions in problems of radar signals correlation processing 被引量:3
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作者 V F Kravchenko D V Churikov 《Journal of Measurement Science and Instrumentation》 CAS 2013年第3期231-237,共7页
In this report the combined method of correlation radar signal(RS)processing based on the theory of atomic functions(AF)is examined.Examples of using of new Kravchenko probability weight functions(WF)designs are prese... In this report the combined method of correlation radar signal(RS)processing based on the theory of atomic functions(AF)is examined.Examples of using of new Kravchenko probability weight functions(WF)designs are presented.Quality functional to estimate accuracy and efficiency of RS processing for concrete physical models is constructed.It is shown that the proposed approach significantly improves the quality of the coherent analysis of RS. 展开更多
关键词 radar signal (RS) atomic funtions (AF) weight functions (WF)CLC number:TN911.7 Document code:AArticle ID:1674-8042(2013)03-0231-07
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Weighted Multi-sensor Data Level Fusion Method of Vibration Signal Based on Correlation Function 被引量:7
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作者 BIN Guangfu JIANG Zhinong +1 位作者 LI Xuejun DHILLON B S 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期899-904,共6页
As the differences of sensor's precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery... As the differences of sensor's precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery fault diagnosis.The traditional signal processing methods,such as classical inference and weighted averaging algorithm usually lack dynamic adaptability that is easy for trends to cause the faults to be misjudged or left out.To enhance the measuring veracity and precision of vibration signal in rotary machine multi-sensor vibration signal fault diagnosis,a novel data level fusion approach is presented on the basis of correlation function analysis to fast determine the weighted value of multi-sensor vibration signals.The approach doesn't require knowing the prior information about sensors,and the weighted value of sensors can be confirmed depending on the correlation measure of real-time data tested in the data level fusion process.It gives greater weighted value to the greater correlation measure of sensor signals,and vice versa.The approach can effectively suppress large errors and even can still fuse data in the case of sensor failures because it takes full advantage of sensor's own-information to determine the weighted value.Moreover,it has good performance of anti-jamming due to the correlation measures between noise and effective signals are usually small.Through the simulation of typical signal collected from multi-sensors,the comparative analysis of dynamic adaptability and fault tolerance between the proposed approach and traditional weighted averaging approach is taken.Finally,the rotor dynamics and integrated fault simulator is taken as an example to verify the feasibility and advantages of the proposed approach,it is shown that the multi-sensor data level fusion based on correlation function weighted approach is better than the traditional weighted average approach with respect to fusion precision and dynamic adaptability.Meantime,the approach is adaptable and easy to use,can be applied to other areas of vibration measurement. 展开更多
关键词 vibration signal MULTI-SENSOR data level fusion correlation function weighted value
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Criterion for Blind Signals Separation Based on Correlation Function 被引量:1
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作者 宋友 柳重堪 李其汉 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2003年第3期162-168,共7页
Blind separation of source signals usually relies either on the condition of statistically independence or involving their higher-order cumulants. The model of two channels signal separation is considered. A criterion... Blind separation of source signals usually relies either on the condition of statistically independence or involving their higher-order cumulants. The model of two channels signal separation is considered. A criterion based on correlation functions is proposed. It is proved that the signals can be separated, using only the condition of noncorrelation. An algorithm is derived, which only involves the solution to quadric nonlinear equations. 展开更多
关键词 blind signals separation independent component analysis CUMULANTS correlation function
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油菜素内酯及其在园艺植物中的研究进展
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作者 郑婷 程建徽 +2 位作者 魏灵珠 向江 吴江 《分子植物育种》 北大核心 2026年第4期1346-1354,共9页
油菜素内酯(BR)作为一种新型、高效的植物激素,在植物的生长发育以及响应生物、非生物胁迫过程中发挥着不可或缺的作用。它能够通过提高植物的光合作用和抗逆性促进植物的生长发育,影响果实产量和品质形成,提高园艺产品在采后贮藏中的... 油菜素内酯(BR)作为一种新型、高效的植物激素,在植物的生长发育以及响应生物、非生物胁迫过程中发挥着不可或缺的作用。它能够通过提高植物的光合作用和抗逆性促进植物的生长发育,影响果实产量和品质形成,提高园艺产品在采后贮藏中的品质。本文综述了油菜素内酯的结构和生物学功能、生物合成和信号转导途径,尤其在调控园艺植物生长发育、品质形成、采后贮藏和抗逆方面的研究进展,并探讨了其研究方向和应用前景,旨在为油菜素内酯的进一步研究提供借鉴。 展开更多
关键词 油菜素内酯 园艺作物 生物学功能 生物合成 信号转导
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生长抑制因子4在子宫内膜癌中的表达及生物学功能研究
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作者 张婷 卫元 +5 位作者 来梦杰 李君盈 陈陈 杜艳敏 郭永真 曾宪旭 《临床肿瘤学杂志》 2026年第1期1-8,共8页
目的探讨生长抑制因子4(ING4)在子宫内膜癌(EC)中的表达及其对癌细胞生物学功能的影响。方法收集138例子宫内膜组织标本,包括30例正常子宫内膜(NE)、31例不伴非典型性子宫内膜增生(EHA)、30例非典型性子宫内膜增生(EAH)及47例EC组织,通... 目的探讨生长抑制因子4(ING4)在子宫内膜癌(EC)中的表达及其对癌细胞生物学功能的影响。方法收集138例子宫内膜组织标本,包括30例正常子宫内膜(NE)、31例不伴非典型性子宫内膜增生(EHA)、30例非典型性子宫内膜增生(EAH)及47例EC组织,通过免疫组化检测ING4、肿瘤蛋白53(p53)、细胞周期蛋白依赖性激酶抑制剂1A(p21)及细胞周期蛋白依赖性激酶抑制剂2A(p16)的蛋白表达。通过慢病毒转染构建稳定过表达ING4(Ad-ING4组)及阴性对照(NC组)的Ishikawa和HEC-1B细胞株。通过实时荧光定量PCR检测ING4、p53、含半胱氨酸的天冬氨酸蛋白水解酶-3(CASP3)、B细胞淋巴瘤-2(Bcl-2)及Bcl-2相关X蛋白(Bax)的mRNA表达水平,并采用蛋白质印迹检测ING4、p53、p21、p16、CASP3、Bcl-2、Bax、信号转导与转录激活因子3(STAT3)及其磷酸化形式(p-STAT3)的蛋白表达水平。利用细胞计数试剂盒-8(CCK-8)实验、克隆形成实验、划痕愈合实验、Transwell侵袭实验评估细胞增殖、迁移及侵袭能力;通过流式细胞术定量检测细胞凋亡与周期分布。采用过表达ING4的HEC-1B细胞构建裸鼠皮下移植瘤模型,观察ING4过表达对体内肿瘤生长的影响。结果在EC组织中,ING4蛋白表达水平(平均光密度值:0.288±0.056)显著低于NE(0.480±0.077)、EHA(0.506±0.084)及EAH(0.406±0.096)组织(P<0.001),并与p21(r=0.353,P=0.015)和p16(r=0.451,P=0.002)的表达呈显著正相关。在细胞实验中,与NC组相比,Ad-ING4组的Ishikawa和HEC-1B细胞表现出增殖、迁移和侵袭能力受到抑制。具体表现为:Ad-ING4组的EC细胞增殖活力(72 h、96 h)、克隆形成能力、划痕愈合率及Transwell侵袭细胞数均显著降低,同时G1期细胞比例与早期凋亡比例升高。Ad-ING4组细胞中p53/p21/p16信号通路被激活,CASP3表达上调且Bax/Bcl-2比值增加,而p-STAT3的蛋白表达则受到抑制。在体内动物实验中,Ad-ING4组裸鼠的皮下移植瘤体积显著小于NC组[(89.00±7.55)mm^(3)vs.(206.70±8.51)mm^(3),P<0.01],且瘤体内ING4、p53、p16的蛋白表达水平更高。结论ING4在EC中低表达,其过表达可通过激活p53/p21/p16通路、促进凋亡并抑制STAT3磷酸化,有效抑制肿瘤细胞的增殖、侵袭及体内成瘤,提示ING4具有肿瘤抑制功能。 展开更多
关键词 子宫内膜癌 生长抑制因子4 生物学功能 信号转导与转录激活因子3
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齐多夫定通过促进脂肪酸氧化改善高脂饮食
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作者 张靖 金子爱 +2 位作者 王紫悦 林君谦 王涛 《中国药科大学学报》 北大核心 2026年第2期256-265,共10页
探讨齐多夫定(AZT)对高脂饮食(HFD)诱导大鼠代谢紊乱的改善作用及其潜在机制。通过建立HFD大鼠模型,设置正常对照组、模型组及AZT低剂量(25 mg/kg)和高剂量(50 mg/kg)干预组,评价AZT对代谢表型、肝脏脂质沉积、氧化应激、线粒体功能以... 探讨齐多夫定(AZT)对高脂饮食(HFD)诱导大鼠代谢紊乱的改善作用及其潜在机制。通过建立HFD大鼠模型,设置正常对照组、模型组及AZT低剂量(25 mg/kg)和高剂量(50 mg/kg)干预组,评价AZT对代谢表型、肝脏脂质沉积、氧化应激、线粒体功能以及过氧化物酶体增殖物激活受体(PPAR)信号通路的影响。结果显示,与模型组相比,AZT显著抑制体重增长,降低腹股沟白色脂肪组织及附睾白色脂肪组织的重量和细胞体积,增强代谢灵活性,并改善葡萄糖耐量且不引起血乳酸升高。高剂量AZT能进一步降低肝脏甘油三酯水平,减轻脂肪变性,并通过提高超氧化物歧化酶(SOD)活性、降低丙二醛(MDA)水平以缓解肝脏氧化应激。蛋白免疫印迹实验结果显示,AZT可上调肝脏PPARα及肉碱棕榈酰转移酶1α(CPT1α)蛋白表达,下调PPARγ表达。综上,AZT能有效改善HFD诱导的代谢紊乱且未引起线粒体毒性,其作用可能与促进脂肪酸氧化、减轻氧化应激、调控PPAR通路和嘧啶代谢有关。 展开更多
关键词 齐多夫定 高脂饮食 代谢紊乱 脂肪酸氧化 氧化应激 线粒体功能 PPAR信号通路
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糖尿病肾病患者肠道菌群状态与AKT/NF-κB信号通路所介导炎性反应的相关性
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作者 魏萌 王萌 +1 位作者 何荃 魏丽敏 《河北医药》 2026年第3期362-366,共5页
目的探讨糖尿病肾病(DKD)患者肠道菌群状态与丝氨酸苏氨酸蛋白激酶(AKT)/核转录因子-κB(NF-κB)信号通路介导的炎性反应的相关性。方法选取2021年5月至2023年8月收治的75例DKD患者为DKD组,另选取同期75例单纯2型糖尿病(T2DM)患者为T2D... 目的探讨糖尿病肾病(DKD)患者肠道菌群状态与丝氨酸苏氨酸蛋白激酶(AKT)/核转录因子-κB(NF-κB)信号通路介导的炎性反应的相关性。方法选取2021年5月至2023年8月收治的75例DKD患者为DKD组,另选取同期75例单纯2型糖尿病(T2DM)患者为T2DM组、75例健康体检者为对照组,比较3组肠道菌群状态、Akt/NF-κB信号通路分子(Akt mRNA、NF-κB mRNA)表达及炎性因子[白介素-6(IL-6)、白介素-1β(IL-1β)、肿瘤坏死因子α(TNF-α)]、糖脂代谢指标[空腹胰岛素(FINS)、空腹血糖(FPG)、低密度脂蛋白胆固醇(LDL-C)、总胆固醇(TC)]、肾功能指标[β2微球蛋白(β2-MG)、血肌酐(Scr)、血尿酸(UA)、血尿素氮(BUN)];分析DKD患者肠道菌群状态与糖脂代谢、肾功能指标、Akt/NF-κB信号通路分子表达及炎性因子的相关性,并分析肠道菌群状态对T2DM进展为DKD的预测价值。结果DKD组双歧杆菌数、真杆菌数低于T2DM组和对照组,大肠杆菌数、粪肠球菌数高于T2DM组和对照组(P<0.05);DKD组Akt mRNA、NF-κB mRNA、IL-6、IL-1β、TNF-α水平均高于T2DM组和对照组(P<0.05);DKD组FPG、FINS、LDL-C、TC、BUN、Scr、β2-MG、UA水平均高于T2DM组和对照组(P<0.05);DKD患者双歧杆菌数、真杆菌数与Akt mRNA、NF-κB mRNA、IL-6、IL-1β、TNF-α、FPG、FINS、LDL-C、TC、BUN、Scr、β2-MG、UA均呈负相关,大肠杆菌数、粪肠球菌数与Akt/NF-κB信号通路分子表达及炎性因子、糖脂代谢及肾功能指标均呈正相关(P<0.05);双歧杆菌数、真杆菌数、大肠杆菌数、粪肠球菌数联合预测的AUC最大,为0.925,具有较高预测价值(P<0.05)。结论DKD患者肠道菌群与糖脂代谢、肾功能及AKT/NF-κB信号通路介导的炎性反应密切相关,检测肠道菌群状态对T2DM进展为DKD有较高的预测价值。 展开更多
关键词 肠道菌群 糖尿病肾病 2型糖尿病 AKT/NF-κB信号通路 糖脂代谢 肾功能
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墨西哥钝口螈尾部再生过程中MyD88介导的Toll样受体信号的功能
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作者 李喆 匡晓旋 +1 位作者 朱玲 梁宇君 《中国海洋大学学报(自然科学版)》 北大核心 2026年第1期146-152,共7页
针对免疫系统在再生过程中具体调控机制不明及Toll样受体(Toll-like receptors,TLR)信号基因与再生速率关联性尚不清楚的问题,本研究以再生模式动物墨西哥钝口螈(Ambystoma mexicanum)为研究对象,旨在揭示MyD88介导的TLR信号基因在其尾... 针对免疫系统在再生过程中具体调控机制不明及Toll样受体(Toll-like receptors,TLR)信号基因与再生速率关联性尚不清楚的问题,本研究以再生模式动物墨西哥钝口螈(Ambystoma mexicanum)为研究对象,旨在揭示MyD88介导的TLR信号基因在其尾部再生过程中的时空表达模式与功能,以解析该信号通路对再生进程的调控作用。本研究综合运用原位杂交、实时定量PCR、药物化学及细胞标记技术。结果表明:TLRs及MyD88在再生过程中表达上调,且呈现再生部位特异表达模式;抑制MyD88介导的TLR信号后,墨西哥钝口螈尾部再生速度快于正常对照组;进一步研究发现,TLR信号的抑制会促进细胞增殖,这在一定程度上解释了本研究中的再生加速现象。本研究明确了MyD88介导的TLR信号基因在再生过程中呈现特异的动态表达模式,推测其可能作为负调控或平衡器发挥作用,为免疫系统参与再生调控的机制研究提供了新视角与关键实验依据。 展开更多
关键词 墨西哥钝口螈 再生 MyD88介导的Toll样受体信号 表达模式 功能 免疫系统
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α-稳定非高斯噪声下基于Arctan-CFRFT的线性调频信号参数估计方法
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作者 兰峰 郭勇 杨立东 《探测与控制学报》 北大核心 2026年第1期98-106,共9页
面对典型的非高斯噪声脉冲噪声,现有线性调频(LFM)信号的参数估计方法大多存在着精度下降甚至是失效的问题,提出一种α-稳定非高斯噪声下基于arctan-CFRFT的LFM信号参数估计方法。首先,构造了一种多参数arctan非线性变换函数,证明该非... 面对典型的非高斯噪声脉冲噪声,现有线性调频(LFM)信号的参数估计方法大多存在着精度下降甚至是失效的问题,提出一种α-稳定非高斯噪声下基于arctan-CFRFT的LFM信号参数估计方法。首先,构造了一种多参数arctan非线性变换函数,证明该非线性变换能有效抑制大幅值的脉冲噪声,且基本不改变信号的时域特征;其次,利用CFRFT建立了信号的分数谱,基于分数谱特征构建LFM信号参数估计的数学模型,并结合浣熊优化算法搜索峰值点;最后,结合噪声修正算法来修正非标准α稳定分布噪声,分析实测脉冲噪声下的参数估计性能。仿真实验表明,该方法能够有效抑制脉冲噪声,能够在脉冲噪声下建立准确的LFM信号分数谱。与现有的基于非线性变换的方法相比,该方法在低GSNR下仍然具有较高的估计精度,实现实测脉冲噪声环境下的LFM信号参数估计。 展开更多
关键词 脉冲噪声 线性调频信号 Arctan函数、简明分数阶傅里叶变换 参数估计
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电力系统宽频振荡信号高可靠性检测研究
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作者 王泽斌 汪芙平 +2 位作者 裴茂林 黄松岭 赵伟 《电测与仪表》 北大核心 2026年第1期45-55,共11页
针对新型电力系统宽频测量中2.5 Hz~300 Hz范围内多目标振荡信号检测问题,研究以高可靠性(极低误检率)作为核心性能的检测算法。采用加窗离散时间傅里叶变换(discrete-time Fourier transform,DTFT)谱峰搜索检测方法,对窗函数的优化设... 针对新型电力系统宽频测量中2.5 Hz~300 Hz范围内多目标振荡信号检测问题,研究以高可靠性(极低误检率)作为核心性能的检测算法。采用加窗离散时间傅里叶变换(discrete-time Fourier transform,DTFT)谱峰搜索检测方法,对窗函数的优化设计进行深入研究。通过理论分析提出高可靠性检测对窗函数频谱特性的约束条件,由此定义窗函数技术指标,并建立窗函数最优化选取准则。基于宽频测量信号检测的信号环境和性能需求,分别针对次/超同步振荡频带(2.5 Hz~100 Hz)和高频振荡频带(100 Hz~300 Hz)给出窗函数优化选取的具体实例。仿真实验结果表明,基于优选窗的DTFT检测算法实际性能与预期设计指标接近,具有高可靠性和适应复杂信号环境能力,在宽频测量中具有重要工程实用价值。 展开更多
关键词 宽频测量 信号检测 傅里叶变换 窗函数设计
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铁路云信号系统软件构件技术及评估方法研究
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作者 王龙生 高筱 +1 位作者 徐中伟 梅萌 《铁道通信信号》 2026年第1期23-29,共7页
近年来,随着全球铁路信号系统数字化转型加速,铁路信号系统云化技术作为重要发展方向已在国际范围内得到广泛关注。相关铁路组织及企业已启动信号系统云化试点工作,初步展示了云平台在铁路信号领域的应用潜力。然而,铁路信号系统作为安... 近年来,随着全球铁路信号系统数字化转型加速,铁路信号系统云化技术作为重要发展方向已在国际范围内得到广泛关注。相关铁路组织及企业已启动信号系统云化试点工作,初步展示了云平台在铁路信号领域的应用潜力。然而,铁路信号系统作为安全苛求系统,其云平台部署面临重大挑战。云环境下计算节点庞大、通信实时性要求高、计算任务汇聚,使得传统软件研发模式难以适应,尤其在实时性保障、分布式节点一致性和虚拟化环境确定性等方面问题突出。为此提出基于软件构件技术的云信号系统软件开发方法,主要包括:基于COMO构件技术的软件架构设计,使系统具有良好的可靠性;利用反射编程技术实现系统运行状态实时监测;建立基于深度学习的数据分析模型,处理云环境中产生的海量监测数据,动态评估系统可靠性。试验表明,将开源COMO构件技术应用于云环境下铁路信号控制系统,可以有效解决虚拟化环境中云信号系统软件开发面临的问题,有利于保证软件质量、增强系统灵活性和可维护性。 展开更多
关键词 云计算 铁路信号系统 功能安全 分布式系统 软件可靠性 COMO构件技术
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中医药改善多囊卵巢综合征子宫内膜容受性的研究进展
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作者 冷亚文 王宇 吴效科 《时珍国医国药》 北大核心 2026年第4期732-737,共6页
多囊卵巢综合征(PCOS)是导致育龄期女性不孕的重要因素,当前治疗以促排卵和辅助生殖技术(ART)为核心。然而,PCOS患者因性激素失衡、糖脂代谢紊乱、子宫内膜局部炎症等因素导致的子宫内膜容受性障碍,仍是影响妊娠成功的关键难题。近年研... 多囊卵巢综合征(PCOS)是导致育龄期女性不孕的重要因素,当前治疗以促排卵和辅助生殖技术(ART)为核心。然而,PCOS患者因性激素失衡、糖脂代谢紊乱、子宫内膜局部炎症等因素导致的子宫内膜容受性障碍,仍是影响妊娠成功的关键难题。近年研究表明,中医药疗法可通过多途径提高PCOS子宫内膜容受性:通过改善子宫内膜血供、调节蜕膜化过程及肠道菌群组成,优化子宫内膜形态与功能;调控PI3K/AKT、TLR4/NF-κB/NLRP3、Wnt/β-catenin、MAPK/ERK等信号通路,促进子宫内膜血管生成并改善免疫微环境;同时减轻ART中激素及促排卵药物对子宫内膜的潜在损伤。文章系统综述了中医药改善PCOS子宫内膜容受性的研究及其作用机制,以期为提升PCOS患者生育能力提供新思路。 展开更多
关键词 多囊卵巢综合征 子宫内膜容受性 中医药 作用机制 信号通路
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可重构信号激励生成设备设计与实现
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作者 顾鹏程 田晓 +1 位作者 陈港 刘鸽 《计算机测量与控制》 2026年第3期301-308,共8页
针对半实物射频仿真测试验证中的复杂电磁环境构建需求,为提供小型多功能信号激励类设备,对雷达及通信信号建模及产生,以及信号回放实现方法进行研究;基于RFSoC芯片,提出了一种可重构功能的信号激励生成设备设计与实现方案;实测结果表明... 针对半实物射频仿真测试验证中的复杂电磁环境构建需求,为提供小型多功能信号激励类设备,对雷达及通信信号建模及产生,以及信号回放实现方法进行研究;基于RFSoC芯片,提出了一种可重构功能的信号激励生成设备设计与实现方案;实测结果表明,信号激励生成设备可通过设置参数方式,实现超宽带雷达、通信激励信号的产生,也可通过信号回放的方式输出事先采集的信号,为室内环境下复杂电磁环境的构建提供有力支撑。 展开更多
关键词 复杂电磁环境 信号模型 雷达信号 通信信号 信号回放 功能可重构
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银杏内酯B调控血小板活化分子机制的研究进展
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作者 何盈 冯文秋 +1 位作者 秦萍 朱培元 《临床输血与检验》 2026年第1期146-152,共7页
银杏内酯B(ginkgolide B,GB)为中药银杏叶中提取的典型二萜内酯类活性成分,具有高效拮抗血小板活化因子(platelet-activating factor,PAF)的作用,可以抑制血小板活化、抗氧化、对抗血栓形成以及保护血管等,尤其在调控血小板活化功能方... 银杏内酯B(ginkgolide B,GB)为中药银杏叶中提取的典型二萜内酯类活性成分,具有高效拮抗血小板活化因子(platelet-activating factor,PAF)的作用,可以抑制血小板活化、抗氧化、对抗血栓形成以及保护血管等,尤其在调控血小板活化功能方面展示出良好的应用前景。机制上,GB可通过多条信号通路发挥作用,包括Ca2+信号通路、PI3K信号通路、花生四烯酸(arachidonic acid,AA)代谢通路及整合素αⅡbβ3介导的信号通路,从而发挥调控血小板活化功能。 展开更多
关键词 银杏内酯B 血小板功能 信号通路 血小板活化
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基于Nrf2/HO-1信号通路探讨黄精多糖对慢性间歇缺氧大鼠认知功能的改善作用 被引量:1
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作者 陆连第 郭琦 +2 位作者 王义义 苗轩 张维维 《中成药》 北大核心 2026年第2期439-446,共8页
目的探讨黄精多糖改善慢性间歇缺氧(CIH)大鼠认知功能损伤的作用机制。方法30只SD大鼠随机分为正常组、模型组和黄精多糖低、中、高剂量组(100、200、400 mg/kg),每组6只。使用间歇低氧箱循环低氧/复氧方法建立CIH大鼠模型,各组灌胃给药... 目的探讨黄精多糖改善慢性间歇缺氧(CIH)大鼠认知功能损伤的作用机制。方法30只SD大鼠随机分为正常组、模型组和黄精多糖低、中、高剂量组(100、200、400 mg/kg),每组6只。使用间歇低氧箱循环低氧/复氧方法建立CIH大鼠模型,各组灌胃给药4周后,测定大鼠体质量;Morris水迷宫实验评估大鼠行为学变化;试剂盒检测大鼠血清及海马组织中炎症因子(IL-1β、TNF-α)和氧化应激指标(SOD、MDA)水平;HE染色观察海马CA1区神经元形态学变化;免疫组化(IHC)染色观察海马CA1区神经元cleaved-Caspase3表达;DCFH-DA荧光探针检测海马组织ROS表达;RT-qPCR和Western blot法检测海马组织Nrf2、HO-1、HIF-1α、NF-κB、NLRP3 mRNA和蛋白表达。结果与正常组比较,模型组大鼠体质量降低(P<0.05),逃避潜伏期延长(P<0.05),穿越平台次数和目标象限停留时间减少(P<0.05);海马CA1区神经细胞排列紊乱,间隙增大;cleaved-Caspase3蛋白阳性率升高(P<0.01);血清和海马组织中MDA、IL-1β、TNF-α和HIF-1α水平升高(P<0.05,P<0.01),SOD活性降低(P<0.05,P<0.01);海马组织中ROS水平升高(P<0.05),Nrf2、HO-1 mRNA和蛋白表达降低(P<0.05),NF-κB、NLRP3、HIF-1αmRNA和蛋白表达升高(P<0.05)。与模型组比较,黄精多糖中、高剂量组大鼠体质量升高(P<0.05),逃避潜伏期缩短(P<0.05),穿越平台次数和目标象限停留时间增加(P<0.05);海马CA1区组织损伤减轻,神经细胞排列较为整齐;cleaved-Caspase3蛋白阳性率降低(P<0.01);血清和海马组织中MDA、IL-1β、TNF-α和HIF-1α水平降低(P<0.05,P<0.01),SOD活性升高(P<0.05,P<0.01);海马组织中Nrf2、HO-1 mRNA和蛋白表达升高(P<0.05),NF-κB、NLRP3、HIF-1αmRNA和蛋白表达降低(P<0.05)。结论黄精多糖可改善CIH大鼠学习及记忆认知功能,减轻海马区神经元损伤,其机制可能与激活Nrf2/HO-1信号通路,拮抗HIF-1α发挥抗氧化应激及抗炎作用有关。 展开更多
关键词 黄精多糖 慢性间歇缺氧 Nrf2/HO-1信号通路 氧化应激 认知功能 HIF-1Α
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