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A new cellular automaton model for traffic flow considering realistic turn signal effect 被引量:3
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作者 SHANG HuaYan PENG Yu 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第6期1624-1630,共7页
In real traffic,any vehicle must give lane-changing signal(i.e.the turn signal) before changing lanes;at this time,the vehicles behind the lane-changing vehicle will be hindered and may form "plugs" due to t... In real traffic,any vehicle must give lane-changing signal(i.e.the turn signal) before changing lanes;at this time,the vehicles behind the lane-changing vehicle will be hindered and may form "plugs" due to the turn signal effect.However,few studies focus on exploring the effect.In this paper,the turn signal effect was taken into account by proposing a new symmetric two-lane cellular automaton(T-STCA) model,and the new model was set to compare with the STCA,H-STCA and A-STCA models.Numerical results show that using the T-STCA model to describe lane-changing or overtaking,the process appeared in several consecutive time steps;while using the other three models,the process appeared only in one time step.In addition,the T-STCA model could describe the mixed traffic flow more realistically and the turn signal effect could help the plugs to dissolve more quickly. 展开更多
关键词 turn signal effect cellular automaton mixed traffic flow
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Green supply chain management and low-carbon innovation spillover effects
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作者 Xueqin Li Chenyang Meng Daqian Shi 《Chinese Journal of Population,Resources and Environment》 2025年第4期480-493,共14页
Supply chain partnerships are an essential component of business innovations.This study uses data on A-share listed companies on the Shanghai and Shenzhen stock exchanges from 2012 to 2022 to conduct a multi-period di... Supply chain partnerships are an essential component of business innovations.This study uses data on A-share listed companies on the Shanghai and Shenzhen stock exchanges from 2012 to 2022 to conduct a multi-period difference-in-differences analysis based on a list of green supply chain management(GSM)companies.We find that GSM significantly promotes low-carbon technology innovations(LCT)of upstream enterprises.The mechanism analysis indicates that GSM has a resource effect and signal effect that generate LCT spillovers.In terms of the resource effect,GSM companies offer green credit and support green procurement,thereby providing financial support for green investments in upstream LCT.In terms of a signaling effect,GSM strengthens the effectiveness of institutional investors,the public,and online media in supervising upstream suppliers’green credentials,thereby promoting upstream LCT.A heterogeneity analysis shows that when midstream companies are state-owned enterprises or industry leaders,and when the concentration and stability of supply chain purchase relationships are higher,the LCT spillover effects of GSM are more pronounced.Further analysis reveals that GSM has bidirectional horizontal spillover effects and that upstream unidirectional vertical spillover effects are limited to first-level suppliers.Additionally,under the premise of not compromising economic benefits and stability,GSM shows an emerging trend of transitioning from environmentally compliant“light green”supply chains to“deep green”supply chains focused on pollution reduction,carbon reduction,and energy conservation. 展开更多
关键词 Green supply chain management(GSM) Low-carbon technology innovation(LCT) Resource effect signal effect Difference-in-differences model(DID)
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Autophagy-Inducing Effect of Compound Berberine on CNE2 NPC Cells via Interference with the Targets in P13K/AKT/mTOR Signaling Pathway 被引量:1
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作者 Yuqin Liu Suhua Yu +7 位作者 Ting Lin Shijie Huang Zhenfeng Zhou Shuhua Chen Xiang Liu Yingchun He Jingying Fan Daofa Tian 《International Journal of Clinical Medicine》 2020年第4期163-181,共19页
Objective: To investigate the autophagy-inducing effect of Compound Berberine (CBBR) on CNE2 nasopharyngeal carcinoma (NPC) cells and its possible targets in P13K/AKT/mTOR signaling pathway. Methods: CNE2 cells at exp... Objective: To investigate the autophagy-inducing effect of Compound Berberine (CBBR) on CNE2 nasopharyngeal carcinoma (NPC) cells and its possible targets in P13K/AKT/mTOR signaling pathway. Methods: CNE2 cells at exponential growth phase were taken as the target cells in this study. Firstly, IC50 concentration for CBBR was determined by MTT assay. Then, 3 different concentrations of CBBR, 0.25 mg&sdot;mL&minus;1, 0.50 mg&sdot;mL&minus;1 and 1.00 mg&sdot;mL&minus;1, around the concentration of IC50, were taken for followed intervention experiments respectively. Fluorescein labeling method was utilized to assay the inducing effect of CBBR on the autophagic activity of CNE2 cells, followed by Western blot procedure to explore the changes of key messenger molecules in the autophagy-related signaling pathway of P13K/AKT/mTOR, both combined with 3-MA block test in a comparative way and carried out by detecting the expressive levels of Beclin 1, LC3-II and LC3-I as well as the ratio of LC3-II:LC3-I. Results: IC50 of CBBR was determined at the level of 0.5 mg&sdot;mL&minus;1. The inducing effect of CBBR on autophagy of CNE2 cells was shown occurring in various modes, not a simple concentration-dependent tendency, with its effect minimal at the concentration of 0.25 mg&sdot;mL&minus;1 and maximal at the concentration of 0.50 mg&sdot;mL&minus;1, while only slightly higher at the concentration of 1.00 mg&sdot;mL&minus;1 than that of 0.5 mg&sdot;mL&minus;1. Although its inducing effect was weakened a little following the pretreatment by 3-MA, the effect combined with CBBR was still significantly higher than that of simply blocked by 3-MA. Moreover, changes in the expressive levels of Beclin1, LC3-II and LC3-I as well as LC3-II:LC3-I all showed a tendency corresponding to the changed autophagic features of CNE2 cells (P Conclusions: CBBR can bring about inhibiting effect on the proliferating activity of CNE2 cells through inducing increased autophagic activity via intervening targets in P13K/AKT/mTOR signaling pathway, and this effect could not be completely blocked by the antagonist 3-MA. 展开更多
关键词 NPC CELLS COMPOUND BERBERINE AUTOPHAGY signaling Pathway Intervening effect
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Signal modulating noise effect in bistable stochastic resonance systems and its analog simulation
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作者 肖方红 闫桂荣 谢世成 《Journal of Central South University of Technology》 EI 2006年第5期595-597,共3页
The effect of signal modulating noise in bistable stochastic resonance systems was studied theoretically and experimentally. A mathematical analysis was made on the bistable stochastic resonance model with small syste... The effect of signal modulating noise in bistable stochastic resonance systems was studied theoretically and experimentally. A mathematical analysis was made on the bistable stochastic resonance model with small system parameters. An analogue circuit was designed to perform the effect. The effect of signal modulating noise was shown in the analog simulation experiment. The analog experiment was conducted for two sinusoidal signals with different frequencies. The results show that there are a sinusoidal component corresponding to the input sinusoidal signal and a noise component presented as a Wiener process corresponding to the input white noise in the system output. By properly selecting system parameters, the effect of signal modulating noise can be manifested in the system output. 展开更多
关键词 signal modulating noise effect bistable system stochastic resonance analog simulation
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SIGNAL SAMPLING DEPTH-INDUCED SKEW EFFECT IN SIMS DEPTH PROFILING
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作者 Ye Hongzhen Microelectronics Center, Academia Sinica, P. O. Box: 650, 100010, Beijing Yu Chunfu Shanghai Institute of Testing Technology, 200233, Shanghai 《真空科学与技术学报》 EI CAS CSCD 1992年第Z1期171-174,共4页
The effect of signal sampling depth in SIMS on profile was not reported We have found that the maximum sampling depth in SIMS is considerably bigger than the mean penetration range of primary ions and can skew the pro... The effect of signal sampling depth in SIMS on profile was not reported We have found that the maximum sampling depth in SIMS is considerably bigger than the mean penetration range of primary ions and can skew the profile of secondary ion counts for implanted samples on the more deeper direction from the surface. The effect of maximum sampling depth is true not only for implanted samples but also for the samples in the middle of which there is an other impurity-rich layer. The action principle of signal sampling depth effect and the method of decreasing the error produced by the effect are discussed in this 展开更多
关键词 SIMS signal SAMPLING DEPTH-INDUCED SKEW effect IN SIMS DEPTH PROFILING
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Effects of Omethoate on Liver Insulin Signaling in Mice
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作者 WANG Yuan LI Yu Ling +4 位作者 MENG Fan Zhu HOU Bao Lian ZHUANG Chuan Ning XIONG Shu Han REN Shu Ping 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第8期627-631,共5页
According to the report of the International Diabetes Federation, there were 382 million people affected with diabetes in 2013 and it is expected that this number will increase to 592 million by the year 2035;. Diabet... According to the report of the International Diabetes Federation, there were 382 million people affected with diabetes in 2013 and it is expected that this number will increase to 592 million by the year 2035;. Diabetes is caused due to the interaction between environmental and genetic factors;. 展开更多
关键词 Akt PI effects of Omethoate on Liver Insulin signaling in Mice PGC IRS
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Detection of the anthropogenic signal and urbanization effects in extreme temperature changes in eastern China
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作者 Ying Sun Ting Hu 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第2期55-62,共8页
作为中国经济最发达的地区,中国东部受到城市热岛效应和温室气体排放等人类活动的明显影响.本文利用最新的观测和全球气候模式资料,对极端温度强度,频率和持续时间等16个极端温度指数进行了检测归因分析,研究了人为强迫和城市化效应对... 作为中国经济最发达的地区,中国东部受到城市热岛效应和温室气体排放等人类活动的明显影响.本文利用最新的观测和全球气候模式资料,对极端温度强度,频率和持续时间等16个极端温度指数进行了检测归因分析,研究了人为强迫和城市化效应对中国东部极端温度变化的影响.结果表明,近年来极端温度持续增暖,极端暖事件增加,极端冷事件减少.新一代全球气候模式能够合理地反映这些变暖特征,但是部分模式可能高估或低估了观测到的变化.基于最优指纹方法的双信号检测表明,人为信号和城市化效应只能在暖夜和冷夜两个频率指标上同时被检测并分离,其变化约三分之二可归因于人类活动,剩余的三分之一可归因于城市化效应.而在极端温度其他指数的变化中,只有人类活动的影响能够被检测到. 展开更多
关键词 城市化效应 人为信号 极端温度 检测 CMIP6
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Signal transducer and activator of transcription 3 promotes the Warburg effect possibly by inducing pyruvate kinase M2 phosphorylation in liver precancerous lesions 被引量:10
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作者 Yang-Hui Bi Wen-Qi Han +4 位作者 Ruo-Fei Li Yun-Jiao Wang Zun-Shu Du Xue-Jiang Wang Ying Jiang 《World Journal of Gastroenterology》 SCIE CAS 2019年第16期1936-1949,共14页
BACKGROUND Study shows that signal transducer and activator of transcription 3(STAT3) can increase the Warburg effect by stimulating hexokinase 2 in breast cancer and upregulate lactate dehydrogenase A and pyruvate de... BACKGROUND Study shows that signal transducer and activator of transcription 3(STAT3) can increase the Warburg effect by stimulating hexokinase 2 in breast cancer and upregulate lactate dehydrogenase A and pyruvate dehydrogenase kinase 1 in myeloma. STAT3 and pyruvate kinase M2(PKM2) can also be activated and enhance the Warburg effect in hepatocellular carcinoma. Precancerous lesions are critical to human and rodent hepatocarcinogenesis. However, the underlying molecular mechanism for the development of liver precancerous lesions remains unknown. We hypothesized that STAT3 promotes the Warburg effect possibly by upregulating p-PKM2 in liver precancerous lesions in rats.AIM To investigate the mechanism of the Warburg effect in liver precancerous lesions in rats.METHODS A model of liver precancerous lesions was established by a modified Solt-Farber method. The liver pathological changes were observed by HE staining and immunohistochemistry. The transformation of WB-F344 cells induced with Nmethyl-N'-nitro-N-nitrosoguanidine and hydrogen peroxide was evaluated by the soft agar assay and aneuploidy. The levels of glucose and lactate in the tissue and culture medium were detected with a spectrophotometer. The protein levels of glutathione S-transferase-π, proliferating cell nuclear antigen(PCNA), STAT3,and PKM2 were examined by Western blot and immunofluorescence.RESULTS We found that the Warburg effect was increased in liver precancerous lesions in rats. PKM2 and p-STAT3 were upregulated in activated oval cells in liverprecancerous lesions in rats. The Warburg effect, p-PKM2, and p-STAT3 expression were also increased in transformed WB-F344 cells. STAT3 activation promoted the clonal formation rate, aneuploidy, alpha-fetoprotein expression,PCNA expression, G1/S phase transition, the Warburg effect, PKM2 phosphorylation, and nuclear translocation in transformed WB-F344 cells.Moreover, the Warburg effect was inhibited by stattic, a specific inhibitor of STAT3, and further reduced in transformed WB-F344 cells after the intervention for PKM2.CONCLUSION The Warburg effect is initiated in liver precancerous lesions in rats. STAT3 activation promotes the Warburg effect by enhancing the phosphorylation of PKM2 in transformed WB-F344 cells. 展开更多
关键词 WARBURG effect Hepatic PROGENITOR cell signal transducer and activator of transcription 3 PYRUVATE kinase M2 LIVER PRECANCEROUS lesion
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Radio Frequency Environment Effect Algorithms and Implementation in Signal-level Radar System Simulation
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作者 WANG Quanmin WANG Chuncai GUO Gang HUANG Kedi 《系统仿真技术》 2009年第1期45-54,共10页
In radar system simulation,the reliability of simulation results depends not only on radar and target models,but also on radio frequency (RF) environment models,including clutter,multipath,diffraction,atmosphere refra... In radar system simulation,the reliability of simulation results depends not only on radar and target models,but also on radio frequency (RF) environment models,including clutter,multipath,diffraction,atmosphere refraction and attenuation.In traditional radar function simulation,all of these factors are grouped into a single pattern-propagation factor and can only give limited information for radar models.In signal-level simulation,radar models require simulated echoes should include information such as delay,doppler frequency,polarization,etc.By discussing and analyzing the principles and algorithms of RF environment effects (clutter,multipath,diffraction,atmosphere refraction and attenuation),this paper is supposed to provide a general RF environment model in signal-level.Algorithms for the Weibull clutter with Gaussian power spectral density (PSD) is discussed;A standard multipath and diffraction algorithm is analyzed,and the spherical earth and knife edge(SEKE)diffraction algorithm is introduced;The ray-tracing algorithm and the effective earth model are discussed;Algorithms for the absorption of oxygen and vapor are introduced;For certain algorithms,some practical advice is given.Finally,an object-oriented RF environment effects model is implemented,which has been dedicatedly designed for signal-level simulations and can provide relatively authentic simulated RF environment for the signal-level simulation of radar systems.Two simulation examples including clutter model and multipath and diffraction model are carried out and analyzed. 展开更多
关键词 雷达 系统仿真技术 偏振 射线追踪算法 计算方法
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5G Oriented Exponential Effective Signal to Interference plus Noise Ratio Mapping Algorithm Based on Channel Classification
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作者 WU Haoran YE Jianfang 《Journal of Donghua University(English Edition)》 EI CAS 2018年第2期160-162,共3页
In the future the fifth generation( 5 G) communication systems,channel models may be very complicated and it is difficult to calculate equivalent signal to interference plus noise ratio( SINR)of a random fading channe... In the future the fifth generation( 5 G) communication systems,channel models may be very complicated and it is difficult to calculate equivalent signal to interference plus noise ratio( SINR)of a random fading channel. Therefore,methods for the calculation of equivalent SINR of a random fading channel are very necessary.In this paper,an enhanced algorithm on the exponential effective SINR mapping( EESM) model for random fading channels was proposed. First, the optimal adjustment parameters of typical channel fading models including extended pedestrian A( EPA)model,extended vehicular A( EVA) model and extended typical urban( ETU) model were obtained by simulation. Then the proposed solution was used to actualize channel classification according to the maximum multipath delay and the average power of the random channel. The solution can determine the typical channel closest to random channel for obtaining the optimal adjustment value of EESM. The evaluation results indicate that the proposed one can improve the whole system throughput significantly and meanwhile the accuracy of the link prediction algorithm is also guaranteed. 展开更多
关键词 the fifth generation (5G) signal to INTERFERENCE PLUS noiseratio (SINR) EXPONENTIAL effectIVE SINR mapping (EESM) channel classification
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Protective effects of panax notoginseng saponin on dextran sulfate sodium-induced colitis in rats through phosphoinositide-3-kinase protein kinase B signaling pathway inhibition 被引量:6
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作者 Qing-Ge Lu Li Zeng +4 位作者 Xiao-Hai Li Yu Liu Xue-Feng Du Guo-Min Bai Xin Yan 《World Journal of Gastroenterology》 SCIE CAS 2020年第11期1156-1171,共16页
BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many c... BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many complications.AIM To explore the protective effects of panax notoginseng saponin(PNS) against dextran sulfate sodium(DSS)-induced intestinal inflammatory injury through phosphoinositide-3-kinase protein kinase B(PI3K/AKT) signaling pathway inhibition in rats.METHODS Colitis rat models were generated via DSS induction, and rats were divided into control(no modeling), DSS, DSS + PNS 50 mg/k, and DSS + PNS 100 mg/kg groups. Then, the intestinal injury, oxidative stress parameters, inflammatory indices, tight junction proteins, apoptosis, macrophage polarization, and TLR4/AKT signaling pathway in colon tissues from rats in each of the groups were detected. The PI3 K/AKT signaling pathway in the colon tissue of rats was blocked using the PI3K/AKT signaling pathway inhibitor, LY294002.RESULTS Compared with rats in the control group, rats in the DSS group showed significantly shortened colon lengths, and significantly increased disease activity indices, oxidative stress reactions and inflammatory indices, as well as significantly decreased expression of tight junction-associated proteins. In addition, the DSS group showed significantly increased apoptotic cell numbers,and showed significantly increased M1 macrophages in spleen and colon tissues.They also showed significantly decreased M2 macrophages in colon tissues, as well as activation of the PI3K/AKT signaling pathway(all P < 0.05). Compared with rats in the DSS group, rats in the DSS + PNS group showed significantly lengthened colon lengths, decreased disease activity indices, and significantly alleviated oxidative stress reactions and inflammatory responses. In addition, this group showed significantly increased expression of tight junction-associated proteins, significantly decreased apoptotic cell numbers, and significantly decreased M1 macrophages in spleen and colon tissues. This group further showed significantly increased M2 macrophages in colon tissues, and significantly suppressed activation of the PI3K/AKT signaling pathway, as well as a dose dependency(all P < 0.05). When the PI3K/AKT signaling pathway was inhibited, the apoptosis rate of colon tissue cells in the DSS + LY294002 group was significantly lower than that of the DSS group(P < 0.05).CONCLUSION PNS can protect rats against DSS-induced intestinal inflammatory injury by inhibiting the PI3K/AKT signaling pathway, and therefore may be potentially used in the future as a drug for colitis. 展开更多
关键词 Panax notoginseng SAPONIN Phosphoinositide-3-kinase protein KINASE B signaling pathway Dextran sulfate sodium COLITIS Rat intestine Protective effect
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考虑电感变化的永磁同步电动机MTPA控制方法
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作者 李峰 宋佳星 《微特电机》 2026年第1期76-81,共6页
现有基于虚拟正弦信号注入(virtual sine signal injection,VSSI)的最大转矩电流比(maximum torque per ampere,MTPA)控制方法以理想永磁同步电动机(permanent magnet synchronous machine,PMSM)数学模型为理论基础,未考虑电感变化带来... 现有基于虚拟正弦信号注入(virtual sine signal injection,VSSI)的最大转矩电流比(maximum torque per ampere,MTPA)控制方法以理想永磁同步电动机(permanent magnet synchronous machine,PMSM)数学模型为理论基础,未考虑电感变化带来的不利影响。为了提升MTPA控制效果,增加考虑磁路交叉耦合效应,提出在线电感辨识方法和改进的MTPA控制方法。基于帕德逼近与变步长神经网络的电感辨识方法,不仅可以解决辨识模型欠秩问题,而且能够在线更新变化的电感参数,结合改进的基于VSSI的MTPA控制,可以有效降低电流矢量角误差,减小定子铜损耗,实现更准确的MTPA控制。通过仿真实验对所提方法的准确性进行了验证。 展开更多
关键词 永磁同步电动机 MTPA控制 虚拟正弦信号注入 交叉耦合效应 电感辨识
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BANCR/miR-145-5p-Reg3A/DMBT1轴驱动AKT-GLUT1/HK2介导的胃癌Warburg效应
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作者 王亮 梁育飞 +1 位作者 赵艳 林杉 《肿瘤防治研究》 2026年第2期112-120,共9页
目的探究BANCR/miR-145-5p轴通过下游靶点Reg3A/DMBT1调控AKT-GLUT1/HK2通路介导胃癌Warburg效应的分子机制。方法采用RT-qPCR、Western blot检测胃癌组织及细胞系中BANCR、miR-145-5p、Reg3A/DMBT1的表达;双荧光素酶报告基因实验验证... 目的探究BANCR/miR-145-5p轴通过下游靶点Reg3A/DMBT1调控AKT-GLUT1/HK2通路介导胃癌Warburg效应的分子机制。方法采用RT-qPCR、Western blot检测胃癌组织及细胞系中BANCR、miR-145-5p、Reg3A/DMBT1的表达;双荧光素酶报告基因实验验证靶向调控关系;葡萄糖摄取检测评估糖酵解能力;免疫组织化学分析60对临床样本分子表达;Kaplan-Meier和Cox回归评估BANCR/miR-145-5p-Reg3A/DMBT1轴关键分子的预后价值。结果胃癌组织中BANCR显著高表达而miR-145-5p低表达,与TNM分期晚、淋巴结转移及低分化显著相关。Reg3A和DMBT1被证实为miR-145-5p直接靶标。敲低BANCR或过表达miR-145-5p可显著抑制Reg3A/DMBT1表达,降低AKT磷酸化及GLUT1/HK2水平,从而抑制糖酵解过程。临床分析显示Reg3A/DMBT1高表达与糖酵解标志物呈正相关,且是胃癌不良预后的独立危险因素。结论BANCR/miR-145-5p轴通过靶向Reg3A/DMBT1激活AKT信号通路,促进GLUT1/HK2/LDHA介导的糖酵解,驱动胃癌Warburg效应。该轴可作为胃癌治疗的潜在靶点及预后评估标志物。 展开更多
关键词 胃癌 Warburg效应 BANCR/miR-145-5p轴 糖酵解调控 AKT信号通路
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痰瘀互结证炎症机制及中药对其调控作用的研究进展
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作者 侯晔 胡镜清 《时珍国医国药》 北大核心 2026年第1期2-13,共12页
系统回顾了痰瘀互结证炎症机制与中药调控研究进展。提出炎症是贯穿痰瘀互结证重要生物学基础,并将痰瘀互结证早期(痰瘀相兼期)、中期(痰瘀互结期)和后期(痰瘀互结变化期)与以NF-κB为核心,p38 MAPK、ERK、PI3K/Akt、NLRP3炎症小体等多... 系统回顾了痰瘀互结证炎症机制与中药调控研究进展。提出炎症是贯穿痰瘀互结证重要生物学基础,并将痰瘀互结证早期(痰瘀相兼期)、中期(痰瘀互结期)和后期(痰瘀互结变化期)与以NF-κB为核心,p38 MAPK、ERK、PI3K/Akt、NLRP3炎症小体等多条通路交织形成的动态的、复杂的炎症网络关联起来,绘制痰瘀互结证炎症机制分子网络图;梳理了中药通过多靶点、多通路调控痰瘀互结证炎症网络的关键节点与作用机制,为探索痰瘀互结证的现代科学内涵提供借鉴。 展开更多
关键词 痰瘀互结证 炎症 信号通路 中药调控
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基于SIRT3/PGC-1α/VDAC1信号通路探讨人参-丹参药对对心肌缺血再灌注损伤大鼠的保护作用
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作者 冉清智 陈恒文 《中国中药杂志》 北大核心 2026年第1期221-231,共11页
基于沉默信息调节因子2相关酶类3(SIRT3)/过氧化物酶体增殖物激活受体γ-辅激活因子-1α(PGC-1α)/电压依赖性阴离子通道1(VDAC1)信号通路探讨人参-丹参(RSDS)调节心肌缺血再灌注损伤(MIRI)的机制及作用靶点。该研究通过构建大鼠MIRI模... 基于沉默信息调节因子2相关酶类3(SIRT3)/过氧化物酶体增殖物激活受体γ-辅激活因子-1α(PGC-1α)/电压依赖性阴离子通道1(VDAC1)信号通路探讨人参-丹参(RSDS)调节心肌缺血再灌注损伤(MIRI)的机制及作用靶点。该研究通过构建大鼠MIRI模型,随机分为对照组,模型组,福辛普利组,人参-丹参低、中、高剂量组。通过心脏超声检查、细胞凋亡(TUNEL)染色、苏木素-伊红(HE)与马松(Masson)染色等方法评估心脏功能、细胞凋亡、心肌纤维化等指标。此外,采用ELISA、Western blot及RT-qPCR技术分析血清因子及心肌组织中SIRT3、PGC-1α、VDAC1等关键蛋白和基因的变化,并基于SIRT3/PGC-1α/VDAC1信号通路研究其作用机制。实验结果表明,与模型组相比,人参-丹参显著改善了心脏功能,尤其是人参-丹参高剂量表现出最强的心脏保护作用,显著升高左心室射血分数(LVEF),显著减小左心室舒张末期内径(LVESD),显著提高左心室短轴缩短率(LVFS)。TUNEL染色显示,人参-丹参能够减少心肌细胞的凋亡。Masson染色结果表明,人参-丹参能够显著减轻心肌纤维化。血清中的白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、C反应蛋白(CRP)、肌酸激酶同工酶MB(CK-MB)因子显著下降,而超氧化物歧化酶(SOD)水平显著提高,提示人参-丹参具有较强的抗炎和抗氧化作用。Western blot和RT-qPCR结果表明,人参-丹参通过调节SIRT3/PGC-1α/VDAC1信号通路,显著改善线粒体功能,抑制氧化应激,保护心肌细胞。该研究表明,人参-丹参通过调节SIRT3/PGC-1α/VDAC1信号通路,在多方面显著改善MIRI引起的心脏功能衰竭,减轻心肌细胞凋亡、心肌纤维化及炎症反应。 展开更多
关键词 人参-丹参 心肌缺血再灌注损伤(MIRI) SIRT3/PGC-1α/VDAC1信号通路 心脏保护作用 抗炎抗氧化
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基于磁感电动势考虑磁场角度的钢结构柱检测方法
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作者 何连昇 陈猛 《沈阳工业大学学报》 北大核心 2026年第1期120-127,共8页
【目的】钢结构长期服役过程中,钢构件的应力状态是评估结构安全与健康状态的关键参数。现有基于磁感电动势效应的应力检测方法未考虑磁场方向的影响,磁场角度变化会降低检测结果准确性。因此,通过理论分析和试验研究,量化磁场角度对钢... 【目的】钢结构长期服役过程中,钢构件的应力状态是评估结构安全与健康状态的关键参数。现有基于磁感电动势效应的应力检测方法未考虑磁场方向的影响,磁场角度变化会降低检测结果准确性。因此,通过理论分析和试验研究,量化磁场角度对钢结构柱磁感电动势-应力关系的影响程度。【方法】设计Q235B H型钢短柱轴心受压试验,将锰锌铁氧体U型电磁传感器固定于钢翼缘中心并改变其角度。分级加载过程中,同步采集不同应力水平、不同磁场角度下的磁感电动势信号,所有试验重复两次以保证数据可重复性。基于试验数据,建立不同磁场角度下H型钢柱的磁感电动势-应力关系曲线,分析磁场角度对H型钢柱应力与磁感电动势关系的具体影响规律,明确磁感电动势与应力、磁场角度的定量关系,同时通过磁感电动势梯度均值量化磁场角度对钢结构柱磁感电动势-应力关系的影响程度。【结果】在弹性范围内,磁感电动势与压应力呈显著线性负相关。随着磁场角度的增大,磁感电动势-应力关系曲线的斜率变化显著;磁场方向与主压应力方向平行时,信号灵敏度最高;随着磁场角度的增大,灵敏度呈非线性递减,垂直时灵敏度最低,且不同角度下的关系曲线互不相交。【结论】不同磁场角度下,磁感电动势梯度随应力增加趋于定值,且其均值随磁场方向与加载方向偏离角度的增大而减小,表明磁场角度会影响应力检测结果。基于试验结果建立的磁感电动势-应力数学表达式拟合度较好,且磁感电动势梯度均值与磁场角度符合余弦函数关系。 展开更多
关键词 钢结构柱 磁感电动势 磁场角度 应力 角度效应 磁信号梯度 定量模型 无损检测
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白术通过PI3K/Akt信号通路保护药物诱导的早孕流产模型大鼠作用研究
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作者 唐让让 陶红 +3 位作者 苏晴 李丽丽 黄琪 胡雨 《现代中药研究与实践》 2026年第1期40-46,共7页
目的研究白术保护药物诱导早孕流产模型大鼠作用及其潜在机制。方法取同一天受孕的雌性大鼠灌胃米非司酮(11.5 mg/kg)和米索前列醇(125μg/kg)建立早孕流产大鼠模型,将流产大鼠分为模型组,白术水提液低(0.6 g/kg)、中(1.2 g/kg)、高(2.4... 目的研究白术保护药物诱导早孕流产模型大鼠作用及其潜在机制。方法取同一天受孕的雌性大鼠灌胃米非司酮(11.5 mg/kg)和米索前列醇(125μg/kg)建立早孕流产大鼠模型,将流产大鼠分为模型组,白术水提液低(0.6 g/kg)、中(1.2 g/kg)、高(2.4 g/kg)剂量组及阳性对照组(地屈孕酮片,3.02mg/kg);另取10只正常受孕大鼠仅灌胃生理盐水作为假手术组;机制验证研究部分,以LY294002为抑制剂组。末次给药30 min后,各大鼠以戊巴比妥钠(40 mg/kg)麻醉,计算各大鼠体质量、胚胎数目和胚胎吸收率。腹主动脉取血,取大鼠子宫组织,HE染色法观察大鼠子宫胎盘组织病理变化。酶联免疫吸附试验(ELISA)检测大鼠血清及子宫组织中孕酮(Progesterone,P)、人绒毛膜促性腺激素(β-Human Chorionic Gonadotropin,β-HCG)的水平;ELISA法检测大鼠子宫组织中白介素10(IL-10)、白介素17(IL-17)、转化生长因子-β(TGF-β)的水平。转录组学测定不同组别相关基因表达,KEGG和GO富集分析预测白术可能作用途径。Western Blot法测定相关蛋白表达。结果与假手术组相比,流产大鼠体质量明显下降,胚胎个体小、颜色呈黑褐色且部分出血坏死,胚胎吸收率显著升高,子宫胎盘组织组结构紊乱,相关细胞排列混乱,组织边界模糊,胎盘迷路受损,血管网血窦减少;此外模型组大鼠子宫及血清中P、β-HCG激素水平明显降低,血清中IL-10水平明显降低,血清中IL-17、TGF-β水平明显升高。与模型组相比,白术水提液各剂量组可明显升高大鼠体质量,明显降低胚胎吸收率,改善子宫组织损伤,明显升高P、β-HCG等激素水平及IL-10的水平,降低IL-17、TGF-β等炎性因子水平。转录组学分析结果显示,PI3K/Akt信号通路为白术潜在作用途径。Western Blot验证实验结果显示,与模型组相比,白术水提液可明显升高p-PI3K/PI3K及p-AKT/AKT比值水平,然而此种作用可被PI3K特异性抑制剂LY294002所抑制。结论白术水提液具有保护早孕流产模型大鼠作用,其作用与调控PI3K/Akt有关信号通路有关。 展开更多
关键词 早孕流产 白术 保护作用 PI3K/AKT信号通路
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复方黄芪汤调控VEGF-AKT信号通路抑制血管新生的抗肺癌机制
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作者 钟怡 尹春燕 +6 位作者 廉源沛 蔡佳丽 王地均 聂雪珂 刘产明 申春悌 颜晓静 《中药新药与临床药理》 北大核心 2026年第1期70-81,共12页
目的基于网络药理学、分子对接及动物实验验证揭示复方黄芪汤抗肺癌分子机制。方法通过网络药理学预测复方黄芪汤抗肺癌的核心成分、靶基因和关键信号通路并进行分子对接;构建Lewis荷瘤小鼠模型,设立空白对照组、荷瘤对照组、Pd^(-1)抗... 目的基于网络药理学、分子对接及动物实验验证揭示复方黄芪汤抗肺癌分子机制。方法通过网络药理学预测复方黄芪汤抗肺癌的核心成分、靶基因和关键信号通路并进行分子对接;构建Lewis荷瘤小鼠模型,设立空白对照组、荷瘤对照组、Pd^(-1)抗体组(10 mg·kg^(-1))及复方黄芪汤低、高剂量组(30、60 g·kg^(-1)),统计肿瘤质量和抑瘤率;苏木精-伊红(HE)染色法检测肿瘤及肺组织病理变化,免疫组化法检测肿瘤组织中微血管密度蛋白(FactorⅧ)表达,酶联免疫吸附测定法(ELISA)检测血清中血管内皮生长因子(VEGF)含量,Western Blot法检测肿瘤组织中磷酸化蛋白激酶B(p-AKT)和蛋白激酶B(AKT)蛋白表达。结果从数据库筛选出复方黄芪汤活性成分56个,交集靶点181个,核心靶点9个,对应活性成分8个;基因本体(GO)分析及基因组百科全书(KEGG)信号通路富集分析结果显示,其主要通过调控PI3K-AKT、JAK-STAT、EGFR酪氨酸激酶抑制剂耐药等信号通路抗肺癌。分子对接提示黄芪紫檀烷苷与VEGF及山柰酚、熊竹素、异鼠李素与蛋白激酶Bα(AKT1)具有良好结合力。动物实验验证结果显示,与荷瘤对照组比较,复方黄芪汤高剂量组能显著抑制肿瘤生长,降低肿瘤质量(P<0.01)。HE染色结果显示肿瘤细胞的细胞核大且核分裂相明显,而复方黄芪汤干预后肿瘤细胞排列松散,细胞间隙大,细胞活跃度低。与荷瘤对照组比较,复方黄芪汤高剂量组能显著降低FactorⅧ水平(P<0.001)及VEGF含量(P<0.01);Western Blot结果显示其能显著下调p-AKT/AKT比值(P<0.01)。结论复方黄芪汤可能通过干预VEGF-AKT信号通路,抑制肿瘤血管生成,进而发挥抑瘤作用。 展开更多
关键词 复方黄芪汤 肺癌 抑瘤网络药理学 VEGF-AKT信号通路 血管新生 实验验证 小鼠
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趋肤效应对石油井随钻电磁响应函数的影响研究
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作者 王一安 程瑞雪 王连俊 《石油工业技术监督》 2026年第2期15-21,共7页
针对随钻电磁信号在石油井复杂媒质中的传播特性,研究了不同传输媒质耦合方式对趋肤效应的影响,进而揭示其对信号传播路径及地面接收强度的作用规律。首先,基于电磁波传播特性,结合井下低频无线传输系统,构建了一个“套管-地层-工作液... 针对随钻电磁信号在石油井复杂媒质中的传播特性,研究了不同传输媒质耦合方式对趋肤效应的影响,进而揭示其对信号传播路径及地面接收强度的作用规律。首先,基于电磁波传播特性,结合井下低频无线传输系统,构建了一个“套管-地层-工作液”三维复合结构模型。研究表明,随钻电磁信号在金属套管与导电地层中存在显著的趋肤效应,这使得电流趋向集中在介质表层,进一步加剧了信号的衰减,并复杂化了传播路径。基于此,利用COMSOL Multiphysics仿真平台,模拟了不同耦合方式下电磁场的空间分布及地面接收特性,并提出一种适用于趋肤效应下的随钻电磁响应函数。通过系统分析地层电导率、套管参数、趋肤效应强度及结构耦合方式等关键因素的影响规律,揭示了地层与金属套管在信号传播过程中的阻碍与屏蔽作用,趋肤效应导致的电流密度在套管表面显著集中。实验结果表明,井下电磁信号空间分布特征和接收响应强度变化与所提出的响应函数变化趋势相似,验证了该响应函数的有效性和实用性,为随钻电磁信号传输特性研究提供了理论依据。 展开更多
关键词 石油井 随钻电磁信号 趋肤效应 随钻电磁响应函数 变化趋势
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基于里德伯原子的Loran-C信号接收
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作者 谢奕鹏 雷名威 石猛 《物理学报》 北大核心 2026年第3期243-250,共8页
Loran-C系统凭借其低频信号在抗干扰和穿透能力方面的优势,可作为全球卫星导航系统GNSS(global navigation satellite system)的有效备份,然而,传统Loran-C接收机存在灵敏度低、体积庞大等固有缺陷.本文提出一种基于里德伯原子传感器的L... Loran-C系统凭借其低频信号在抗干扰和穿透能力方面的优势,可作为全球卫星导航系统GNSS(global navigation satellite system)的有效备份,然而,传统Loran-C接收机存在灵敏度低、体积庞大等固有缺陷.本文提出一种基于里德伯原子传感器的Loran-C信号接收机,利用参比电极将Loran-C低频电场耦合至内置平行电极板的原子气室中,并使用直流电场辅助优化,通过电磁感应透明效应结合斯塔克频移效应,实现对电场强度与相位信息的直接高灵敏度测量.研究构建了基于FPGA的硬件采集与MATLAB的信号处理平台,成功实现了天地波识别、时间差提取与定位解算和授时解码,实验验证了该里德伯原子Loran-C接收机的定位以及授时功能.研究表明,里德伯原子传感器有望显著提升Loran-C信号的低频探测灵敏度与动态范围,为发展下一代高可靠、高性能的导航授时系统开辟了量子传感技术的新途径. 展开更多
关键词 里德伯原子 斯塔克效应 电磁感应透明 Loran-C信号
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