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Effects of restrictions on maternal feed intake on the immune indexes of umbilical cord blood and liver Toll-like receptor signaling pathways in fetal goats during pregnancy 被引量:3
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作者 Wenxun Chen Qiongxian Yan +2 位作者 Hong Yang Xiaoling Zhou Zhiliang Tan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第3期736-744,共9页
Background: Liver has important immune function during fetal development and after birth.However,the effect of maternal malnutrition on immune function of the fetal liver is rarely reported.In this study,twelve pregna... Background: Liver has important immune function during fetal development and after birth.However,the effect of maternal malnutrition on immune function of the fetal liver is rarely reported.In this study,twelve pregnant goats(Xiangdong black goat,at d 45 of gestation) were assigned to the control group(fed 100% of nutritional requirements) and the restriction group(fed 60% of the intake of the control group) during gestation from d 55 to100.Fetal goats were harvested at d 100 of gestation and immune indexes and amino acid profiles of the umbilical cord blood and liver Toll-like receptors(TLRs) signaling pathways were measured.Results: Maternal body weight in the restriction group was lower than the control group(P < 0.05).Maternal feed intake restriction decreased(P < 0.05) heart weight,heart index,alkaline phosphatase and serum amyloid protein A in the umbilical cord blood(UCB).Moreover,only histidine was decreased in the restricted group(P = 0.084),and there were no differences in other amino acids contents in the UCB between the two groups(P > 0.05).The TLR2 and TLR4 mRNA expression in the fetal liver in the restriction group was greater(P < 0.05) than that in the control group.Furthermore,the mRNA expression levels of myeloid differentiation primary response 88(MyD88),TNF receptor associated factor 6,nuclear factor kappa B subunit 1,NFKB inhibitor alpha,IFN-β,TGF-β,TNF-α and IL-1β in the restricted group were upregulated(P < 0.05),and the expression of TLR3(P = 0.099) tended to be higher in the restricted group.However,protein levels of TLR2,TLR4,IκBα,phosphorylated IκBα,phosphorylated IκBα/total IκBα,TRIF and MyD88 were not affected(P > 0.05) by maternal intake restriction.Conclusions: These results revealed that the restriction of maternal feed intake influenced the development of heart and hepatic protein synthesis at the acute phase of fetal goats and upregulated the mRNA expression of genes involved in MyD88-dependent signaling pathways and of target cytokines. 展开更多
关键词 Feed intake RESTRICTION FETAL goats Immune cell LIVER TLRS signaling pathway
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LRP6 Bidirectionally Regulates Insulin Sensitivity through Insulin Receptor and S6K Signaling in Rats with CG-IUGR
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作者 Xue-mei XIE Qiu-li CAO +10 位作者 Yu-jie SUN Jie ZHANG Kai-li LIU Ying-fen QIN Wen-jun LONG Zuo-jie LUO Xiao-wei LI Xing-huan LIANG Guan-dou YUAN Xiao-ping LUO Xiu-ping XUAN 《Current Medical Science》 SCIE CAS 2023年第2期274-283,共10页
Objective Intrauterine growth restriction followed by postnatal catch-up growth(CG-IUGR)increases the risk of insulin resistance-related diseases.Low-density lipoprotein receptor-related protein 6(LRP6)plays a substan... Objective Intrauterine growth restriction followed by postnatal catch-up growth(CG-IUGR)increases the risk of insulin resistance-related diseases.Low-density lipoprotein receptor-related protein 6(LRP6)plays a substantial role in glucose metabolism.However,whether LRP6 is involved in the insulin resistance of CG-IUGR is unclear.This study aimed to explore the role of LRP6 in insulin signaling in response to CG-IUGR.Methods The CG-IUGR rat model was established via a maternal gestational nutritional restriction followed by postnatal litter size reduction.The mRNA and protein expression of the components in the insulin pathway,LRP6/β-catenin and mammalian target of rapamycin(mTOR)/S6 kinase(S6K)signaling,was determined.Liver tissues were immunostained for the expression of LRP6 andβ-catenin.LRP6 was overexpressed or silenced in primary hepatocytes to explore its role in insulin signaling.Results Compared with the control rats,CG-IUGR rats showed higher homeostasis model assessment for insulin resistance(HOMA-IR)index and fasting insulin level,decreased insulin signaling,reduced mTOR/S6K/insulin receptor substrate-1(IRS-1)serine307 activity,and decreased LRP6/β-catenin in the liver tissue.The knockdown of LRP6 in hepatocytes from appropriate-for-gestational-age(AGA)rats led to reductions in insulin receptor(IR)signaling and mTOR/S6K/IRS-1 serine307 activity.In contrast,LRP6 overexpression in hepatocytes of CG-IUGR rats resulted in elevated IR signaling and mTOR/S6K/IRS-1 serine307 activity.Conclusion LRP6 regulated the insulin signaling in the CG-IUGR rats via two distinct pathways,IR and mTOR-S6K signaling.LRP6 may be a potential therapeutic target for insulin resistance in CG-IUGR individuals. 展开更多
关键词 intrauterine growth restriction followed by postnatal catch-up growth insulin signaling lipoprotein receptor-related protein 6 Wnt signaling mammalian target of rapamycin/S6 kinase signaling
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Acquisition Practice of High Signal-to-Noise Ratio in YTB Block of Sichuan Basin
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作者 Jun Wu Jiangli Chen +5 位作者 Zhong Li Zengyou Wu Hong Liu Yiwei Li Yong Tang Junguo Du 《Journal of Geoscience and Environment Protection》 2023年第6期229-236,共8页
YTB block in Sichuan basin is a favorable area to exploit oil and gas in shallow tight rock. 3D seismic project of this zone has two characteristics. Firstly, it has high requirements for the tolerance rate of the con... YTB block in Sichuan basin is a favorable area to exploit oil and gas in shallow tight rock. 3D seismic project of this zone has two characteristics. Firstly, it has high requirements for the tolerance rate of the construction process and the acquisition of high signal-to-noise ratio seismic data;Second, there are widely obstacles and noises that lead to difficult acquisition construction organization. In acquisition practice, high signal-to-noise ratio seismic data was obtained by reasonable design of construction scheme, optimization of excitation parameters, improvement of receiving conditions and optimization of obstacle crossing observation system. . 展开更多
关键词 Tight Oil and Gas Tolerance Rate High signal-to-Noise Ratio obstacle
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Diet restriction and exercise alleviate cognitive reduction of high fat diet (HFD)-induced obese mice by rescuing inflammation-mediated compromised insulin signaling pathway through activating AMPK/SIRT1 signal pathway and suppressing TLR4 signal pathway
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作者 Hu Zhang Ye Zhang +7 位作者 Jiling Liang Jiahang Li Miao He Xin Liu Jielun Huang Minghui Wang Jingjing Fan Ning Chen 《Food Science and Human Wellness》 SCIE CAS 2024年第6期3171-3180,共10页
Obesity,caused by excessive energy,leads to body weight gain and various diseases,including cognitive impairment.Current studies suggest that diet restriction such as optimal fasting and regular exercise are crucial f... Obesity,caused by excessive energy,leads to body weight gain and various diseases,including cognitive impairment.Current studies suggest that diet restriction such as optimal fasting and regular exercise are crucial for improving cognitive capacity.However,further exploration is needed to understand the specific mechanisms of high fat diet(HFD)-induced cognitive decline in obesity.In the present study,4-month-old mice were subjected to HFD feeding for 18 weeks,followed by aerobic exercise and high-intensity intermittent exercise,regular diet feeding,and intermittent fasting for 8 weeks,and then used to evaluate cognitive capacity,inflammation,compromised insulin signaling pathway,and apoptosis in hippocampal tissue,as well as AMPK/SIRT1 and TLR4 signal pathways.Obese mice revealed impaired cognitive capacity as compared with mice fed with regular diets.In contrast,aerobic exercise,high-intensity intermittent exercise,regular diet,and intermittent fasting could inhibit apoptosis caused by inflammation-mediated compromised insulin signaling pathway in hippocampal tissues through activating the AMPK/SIRT1 signal pathway and suppressing the TLR4 signal pathway,thereby rescuing the cognitive impairment of obese mice.Therefore,diet restriction and exercise interventions may play a positive role in reverting obesity-induced cognitive impairment. 展开更多
关键词 Cognitive capacity Exercise intervention Diet restriction Inflammation Insulin signaling pathway Obesity
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STABLE RECOVERY OF SPARSELY CORRUPTED SIGNALS THROUGH JUSTICE PURSUIT DE-NOISING
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作者 Ningning Li Wengu Chen Huanmin Ge 《Journal of Computational Mathematics》 SCIE CSCD 2024年第1期271-288,共18页
This paper considers a corrupted compressed sensing problem and is devoted to recover signals that are approximately sparse in some general dictionary but corrupted by a combination of interference having a sparse rep... This paper considers a corrupted compressed sensing problem and is devoted to recover signals that are approximately sparse in some general dictionary but corrupted by a combination of interference having a sparse representation in a second general dictionary and measurement noise.We provide new restricted isometry property(RIP)analysis to achieve stable recovery of sparsely corrupted signals through Justice Pursuit De-Noising(JPDN)with an additional parameter.Our main tool is to adapt a crucial sparse decomposition technique to the analysis of the Justice Pursuit method.The proposed RIP condition improves the existing representative results.Numerical simulations are provided to verify the reliability of the JPDN model. 展开更多
关键词 Justice Pursuit De-Noising Restricted isometry property Corrupted compressed sensing signal recovery
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慕强还是畏强?知识可达性与技术合作创新质量
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作者 侯雪茹 刘明霞 《科技进步与对策》 CSSCI 北大核心 2024年第19期118-127,共10页
知识可达性作为一种优势表征在创新研究中未受到足够重视,可能会影响潜在合作者的评价反馈。基于信号理论考察知识可达性对创新价值的有用性以及对高管连锁网络、知识侵权风险的调节作用,运用2008—2020年汽车制造业上市公司数据进行实... 知识可达性作为一种优势表征在创新研究中未受到足够重视,可能会影响潜在合作者的评价反馈。基于信号理论考察知识可达性对创新价值的有用性以及对高管连锁网络、知识侵权风险的调节作用,运用2008—2020年汽车制造业上市公司数据进行实证检验,结果发现:①知识可达性对焦点企业技术合作创新质量发挥慕强效应,具有正向影响;②高管连锁多样性和连锁密度作为诱发畏强效应的关键要素,负向调节知识可达性与技术合作创新质量关系;③知识侵权风险作为诱发畏强效应的不确定性因素,负向调节知识可达性与技术合作创新质量关系,使高管连锁多样性和连锁密度对知识可达性与技术合作创新质量的负向调节作用在知识侵权风险大的环境中更显著。研究结论可为提升企业知识优势信号吸引力提供理论参考。 展开更多
关键词 技术合作创新质量 知识可达性 高管连锁网络 信号理论 知识侵权风险
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血流限制抗阻训练通过抑制TGF-β1/Smad3信号通路减轻2型糖尿病大鼠肾纤维化
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作者 林秋苹 查宇喆 +3 位作者 刘怡然 喻乾 谭朝文 赵彦 《中国病理生理杂志》 CAS CSCD 北大核心 2024年第8期1470-1478,共9页
目的:探究血流限制抗阻训练对2型糖尿病(T2DM)大鼠肾纤维化的影响及其通过抑制转化生长因子-β1(TGF-β1)/Smad家族成员3(Smad3)信号通路减轻肾纤维化的潜在机制。方法:采用高脂饲料和链脲佐菌素(STZ)联合制备大鼠T2DM模型,造模成功后... 目的:探究血流限制抗阻训练对2型糖尿病(T2DM)大鼠肾纤维化的影响及其通过抑制转化生长因子-β1(TGF-β1)/Smad家族成员3(Smad3)信号通路减轻肾纤维化的潜在机制。方法:采用高脂饲料和链脲佐菌素(STZ)联合制备大鼠T2DM模型,造模成功后随机分为T2DM对照(CON,n=5)组、低负荷抗阻训练(LRT,n=5)组、高负荷抗阻训练(HRT,n=5)组、血流限制(BFR,n=5)组和血流限制抗阻训练(BFRT,n=5)组,进行为期8周的运动训练。记录各组大鼠肾脏指数、空腹血糖(FBG)、血清肌酐(SCr)和血尿素氮(BUN)水平;通过HE和Masson染色观察肾脏形态学变化,并计算胶原容积分数(CVF);RT-qPCR检测肾脏组织中Klotho、TGF-β1和α-平滑肌肌动蛋白(α-SMA)的mRNA表达水平;Western blot检测肾脏组织中Klotho、TGF-β1、Smad3、磷酸化Smad3(p-Smad3)、α-SMA和结缔组织生长因子(CTGF)的蛋白水平。结果:对比其他各组,血流限制抗阻训练组大鼠FBG、SCr、BUN和肾脏CVF显著下降(P<0.05),Klotho表达水平显著上升(P<0.05),TGF-β1、p-Smad3、CTGF和α-SMA表达水平显著下降(P<0.05),Smad3表达水平无显著变化(P>0.05)。结论:血流限制抗阻训练可减轻T2DM大鼠肾纤维化程度,其机制可能与上调Klotho表达,阻断TGF-β1/Smad3信号通路,从而抑制细胞外基质的沉积有关。 展开更多
关键词 2型糖尿病 肾纤维化 血流限制抗阻训练 KLOTHO TGF-β1/Smad3信号通路
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A sharp recovery condition for block sparse signals by block orthogonal multi-matching pursuit 被引量:5
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作者 CHEN WenGu GE HuanMin 《Science China Mathematics》 SCIE CSCD 2017年第7期1325-1340,共16页
We consider the block orthogonal multi-matching pursuit(BOMMP) algorithm for the recovery of block sparse signals.A sharp condition is obtained for the exact reconstruction of block K-sparse signals via the BOMMP algo... We consider the block orthogonal multi-matching pursuit(BOMMP) algorithm for the recovery of block sparse signals.A sharp condition is obtained for the exact reconstruction of block K-sparse signals via the BOMMP algorithm in the noiseless case,based on the block restricted isometry constant(block-RIC).Moreover,we show that the sharp condition combining with an extra condition on the minimum l_2 norm of nonzero blocks of block K-sparse signals is sufficient to ensure the BOMMP algorithm selects at least one true block index at each iteration until all true block indices are selected in the noisy case.The significance of the results we obtain in this paper lies in the fact that making explicit use of block sparsity of block sparse signals can achieve better recovery performance than ignoring the additional structure in the problem as being in the conventional sense. 展开更多
关键词 compressed sensing block sparse signal block restricted isometry property block orthogonal multimatching pursuit
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EXECUTER2 modulates the EXECUTER1 signalosome through its singlet oxygen-dependent oxidation 被引量:3
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作者 Vivek Dogra Rahul Mohan Singh +3 位作者 Mengping Li Mingyue Li Somesh Singh Chanhong Kim 《Molecular Plant》 SCIE CAS CSCD 2022年第3期438-453,共16页
Oxidative post-translational modifications of specific chloroplast proteins contribute to the initiation of retrograde signaling.The Arabidopsis thaliana EXECUTER1(EX1)protein,a chloroplast-localized singlet oxygen(^(... Oxidative post-translational modifications of specific chloroplast proteins contribute to the initiation of retrograde signaling.The Arabidopsis thaliana EXECUTER1(EX1)protein,a chloroplast-localized singlet oxygen(^(1)O_(2))sensor,undergoes tryptophan(Trp)643 oxidation by^(1)O_(2),a chloroplast-derived and light-dependent reactive oxygen species.The indole side chain of Trp is vulnerable to^(1)O_(2),leading to the generation of oxidized Trp variants and priming EX1 for degradation by a membrane-bound FtsH protease.The perception of^(1)O_(2)via Trp643 oxidation and subsequent EX1 proteolysis facilitate chloroplast-to-nucleus retrograde signaling.In this study,we discovered that the EX1-like protein EX2 also undergoes^(1)O_(2)-dependent Trp530 oxidation and FtsH-dependent turnover,which attenuates^(1)O_(2)signaling by decelerating EX1-Trp643 oxidation and subsequent EX1 degradation.Consistent with this finding,the loss of EX2 function reinforces EX1-dependent retrograde signaling by accelerating EX1-Trp643 oxidation and subsequent EX1 proteolysis,whereas overexpression of EX2 produces molecular phenotypes opposite to those observed in the loss-of-function mutants of EX2.Intriguingly,phylogenetic analysis suggests that EX2 may have emerged evolutionarily to attenuate the sensitivity of EX1 toward^(1)O_(2).Collectively,these results suggest that EX2 functions as a negative regulator of the EX1 signalosome through its own^(1)O_(2)-dependent oxidation,providing a new mechanistic insight into the regulation of EX1-mediated^(1)O_(2)signaling. 展开更多
关键词 EXECUTER1 EXECUTER2 singlet oxygen retrograde signaling Trp oxidation FtsH protease
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1O2-Mediated and EXECUTER-Dependent Retrograde Plastid-to-Nucleus Signaling in Norflurazon-Treated Seedlings of Arabidopsis thaliana 被引量:1
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作者 Chanhong Kim Klaus Apel 《Molecular Plant》 SCIE CAS CSCD 2013年第5期1580-1591,共12页
Chloroplast development depends on the synthesis and import of a large number of nuclear-encoded pro- teins. The synthesis of some of these proteins is affected by the functional state of the plastid via a process kno... Chloroplast development depends on the synthesis and import of a large number of nuclear-encoded pro- teins. The synthesis of some of these proteins is affected by the functional state of the plastid via a process known as retrograde signaling. Retrograde plastid-to-nucleus signaling has been often characterized in seedlings of Arabidopsis thaliana exposed to norflurazon (NF), an inhibitor of carotenoid biosynthesis. Results of this work suggested that, throughout seedling development, a factor is released from the plastid to the cytoplasm that indicates a perturbation of plastid homeostasis and represses nuclear genes required for normal chloroplast development. The identity of this factor is still under debate. Reactive oxygen species (ROS) were among the candidates discussed as possible retrograde signals in NF-treated plants. In the present work, this proposed role of ROS has been analyzed. In seedlings grown from the very beginning in the presence of NF, ROS-dependent signaling was not detectable, whereas, in seedlings first exposed to NF after light-dependent chloroplast formation had been completed, enhanced ROS production occurred and, among oth- ers, 1O2-mediated and EXECUTER-dependent retrograde signaling was induced. Hence, depending on the developmental stage at which plants are exposed to NF, different retrograde signaling pathways may be activated, some of which are also active in non-treated plants under light stress. 展开更多
关键词 retrograde signaling singlet oxygen Executer NORFLURAZON programmed cell death photo-oxidative stress.
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美国信号情报活动的最新指导:第14086号行政命令解析
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作者 李星煜 邓娥荣 《情报杂志》 CSSCI 北大核心 2024年第7期34-40,共7页
[研究目的]拜登于2022年10月发布了第14086号行政命令《加强对美国信号情报活动的防护》,对该文件进行细致梳理和研究,可以更加全面地理解美国信号情报工作的指导思想和原则。[研究方法]以第14086号行政命令文本为基础,采用文献研读和... [研究目的]拜登于2022年10月发布了第14086号行政命令《加强对美国信号情报活动的防护》,对该文件进行细致梳理和研究,可以更加全面地理解美国信号情报工作的指导思想和原则。[研究方法]以第14086号行政命令文本为基础,采用文献研读和比较研究的方法,剖析了该行政命令出台的时代背景,系统梳理了其主要内容和创新之处,并进行了较全面的评价。[研究结论]第14086号行政命令是美国对信号情报工作的最新指导,提出了更加具体的工作规范。它继续坚持以美国国家安全利益为优先的理念,秉持区分国籍确定公民保护措施的原则,其内容既体现了应对当前形势的调整,又为未来信号情报工作保留了主动作为的空间。 展开更多
关键词 情报工作 拜登政府 信号情报 行政命令 美国
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脑白质高信号患者执行功能与脑血流量的相关性分析
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作者 常文轩 王婷 +2 位作者 刘伟 李洪义 朱敏 《中国当代医药》 CAS 2024年第14期4-7,36,共5页
目的应用三维动脉自旋标记技术(3D-ASL)探究脑白质高信号患者执行功能的脑灌注机制。方法选取2021年3月至2022年12月就诊于牡丹江医学院附属红旗医院神经内科,存在脑白质高信号的患者104例为病例组,同期与之匹配的健康人群52例为对照组... 目的应用三维动脉自旋标记技术(3D-ASL)探究脑白质高信号患者执行功能的脑灌注机制。方法选取2021年3月至2022年12月就诊于牡丹江医学院附属红旗医院神经内科,存在脑白质高信号的患者104例为病例组,同期与之匹配的健康人群52例为对照组。根据Fazekas分级,将病例组分为轻度组(0~2分)和中重度组(3~6分)。收集两组人群的基线资料,神经心理学评估,包括蒙特利尔评估表、画钟测试、连线测试。所有受试者进行常规序列及3D-ASL检查,同时获得各个脑叶感兴趣区的脑血流量(CBF)值。进行病例组与对照组间执行功能、各个脑叶皮层CBF值差异比较,并分析皮层CBF值与执行功能的相关性。结果轻度组在双侧额叶、丘脑的CBF值低于对照组,中重度组在双侧额叶、顶叶、颞叶、丘脑的CBF均低于其他两组,差异有统计学意义(P<0.05)。轻度组的左侧额叶CBF值与执行功能呈正相关(P<0.05);中重度组的左侧额叶、颞叶CBF值与执行功能呈正相关(P<0.05)。结论执行功能早期下降可能与左侧额叶CBF下降有关,为预测认知功能下降提供了影像学依据。 展开更多
关键词 执行功能 脑白质高信号 动脉自旋标记 认知障碍
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过表达M2型肿瘤相关巨噬细胞TIA1基因通过调控PI3K/AKT信号通路抑制胃癌细胞侵袭和迁移
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作者 钟裕昌 阮笃激 +3 位作者 戴霖 王彪 曲颜 杨雪峰 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第8期1658-1664,共7页
目的:探讨过表达M2型肿瘤相关巨噬细胞(M2-TAMs)T淋巴细胞内抗原1(TIA1)基因对胃癌BGC-823细胞侵袭和迁移的影响及其机制。方法:从胃癌组织中提取原代TAMs,采用IL-4和IL-13刺激TAMs诱导分化成M2-TAMs,再将TIA1基因过表达质粒(oe-TIA1)... 目的:探讨过表达M2型肿瘤相关巨噬细胞(M2-TAMs)T淋巴细胞内抗原1(TIA1)基因对胃癌BGC-823细胞侵袭和迁移的影响及其机制。方法:从胃癌组织中提取原代TAMs,采用IL-4和IL-13刺激TAMs诱导分化成M2-TAMs,再将TIA1基因过表达质粒(oe-TIA1)及其空载质粒(Vector)转染至M2-TAMs中,采用qRT-PCR和Western blot检测细胞中TIA1 mRNA和蛋白表达水平;流式细胞术检测细胞中CD206和CD163表达水平;ELISA检测细胞培养上清液中IL-10、TGF-β、VEGF-A和Arg-1水平。通过Transwell共培养体系将转染后的M2-TAMs与胃癌BGC-823细胞共培养,并联用PI3K激动剂740Y-P进行干预,采用划痕实验检测细胞迁移能力;Transwell实验检测细胞侵袭能力;Western blot检测细胞中PI3K、p-PI3K、AKT、p-AKT、MMP-2和MMP-9等蛋白表达水平。结果:①与原代TAMs比较,M2-TAMs中CD206和CD163表达水平及细胞培养上清液中IL-10、TGF-β、VEGF-A和Arg-1水平均显著升高(P<0.05),而TIA1 mRNA和蛋白表达水平显著降低(P<0.05)。TIA1基因过表达可显著降低M2-TAMs中CD206和CD163表达水平及细胞培养上清液中IL-10、TGF-β、VEGF-A和Arg-1水平(P<0.05)。②M2-TAMs中过表达TIA1基因可显著降低BGC-823细胞迁移和侵袭能力及p-PI3K/PI3K、p-AKT/AKT、MMP-2和MMP-9等蛋白表达水平(P<0.05)。③740Y-P可显著逆转M2-TAMs中过表达TIA1基因对BGC-823细胞迁移、侵袭及PI3K/AKT信号通路的抑制作用。结论:过表达M2-TAMs中TIA1基因表达可通过阻断PI3K/AKT信号通路影响胃癌细胞侵袭和迁移。 展开更多
关键词 M2型肿瘤相关巨噬细胞 T淋巴细胞内抗原1 胃癌细胞 PI3K/AKT信号通路
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面向机器人导航的双目立体视觉处理器综述
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作者 陈卓宇 安丰伟 《集成电路与嵌入式系统》 2024年第11期15-28,共14页
随着机器人产业的快速发展,机器人技术已成为推动生产力提升的新动力,特别是三维重建、避障导航等技术的重要性日益凸显。基于飞行时间(Time of Flight,ToF)和结构光等主动式三维成像技术受限于自身分辨率较低、缺乏色彩信息和易受环境... 随着机器人产业的快速发展,机器人技术已成为推动生产力提升的新动力,特别是三维重建、避障导航等技术的重要性日益凸显。基于飞行时间(Time of Flight,ToF)和结构光等主动式三维成像技术受限于自身分辨率较低、缺乏色彩信息和易受环境光干扰等因素,表现不够理想。因此,能够实时精确输出稠密深度和色彩信息(RGB D)的被动式双目立体视觉传感器在自主移动机器人、汽车和微型无人机等领域得到了广泛应用。然而,双目立体视觉技术通过模仿人类双眼计算视差来提供深度信息,计算复杂度高且依赖于通用计算平台,导致双目立体视觉处理器面临着高能耗和高延迟等问题,这限制了该技术在高速场景、小型机器人和边缘计算等领域的应用。近年来,那些集成了立体视觉算法专用硬件加速器的双目立体视觉处理器在学术界和产业界引起了广泛关注。本文首先系统阐述了双目三维立体视觉的理论基础及其在机器人立体视觉的应用实例,接着介绍了双目立体视觉处理器的组成结构,包括图像获取、相机标定与校正、立体匹配等核心部分。为便于立体视觉硬件开发者参考,本文根据双目立体视觉系统的核心组成结构,分别综述了基本概念、研究现状和难点与挑战,并特别关注和对比了新型硬件计算架构。 展开更多
关键词 机器人 立体视觉 视觉避障导航 图像信号处理器 硬件架构 硬件加速
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THE EXACT RECOVERY OF SPARSE SIGNALS VIA ORTHOGONAL MATCHING PURSUIT
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作者 Anping Liao Jiaxin Xie +1 位作者 Xiaobo Yang PengWang 《Journal of Computational Mathematics》 SCIE CSCD 2016年第1期70-86,共17页
This paper aims to investigate sufficient conditions for the recovery of sparse signals via the orthogonal matching pursuit (OMP) algorithm. In the noiseless case, we present a novel sufficient condition for the exa... This paper aims to investigate sufficient conditions for the recovery of sparse signals via the orthogonal matching pursuit (OMP) algorithm. In the noiseless case, we present a novel sufficient condition for the exact recovery of all k-sparse signals by the OMP algorithm, and demonstrate that this condition is sharp. In the noisy case, a sufficient condition for recovering the support of k-sparse signal is also presented. Generally, the computation for the restricted isometry constant (RIC) in these sufficient conditions is typically difficult, therefore we provide a new condition which is not only computable but also sufficient for the exact recovery of all k-sparse signals. 展开更多
关键词 Compressed sensing Sparse signal recovery Restricted orthogonality constant(ROC) Restricted isometry constant (RIC) Orthogonal matching pursuit (OMP).
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STABLE AND ROBUST RECOVERY OF APPROXIMATELY k-SPARSE SIGNALS WITH PARTIAL SUPPORT INFORMATION IN NOISE SETTINGS VIA WEIGHTED ℓ_(p)(0
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作者 Biao Du Anhua Wan 《Journal of Computational Mathematics》 SCIE CSCD 2023年第6期1137-1170,共34页
In the existing work,the recovery of strictly k-sparse signals with partial support information was derived in theℓ2 bounded noise setting.In this paper,the recovery of approximately k-sparse signals with partial supp... In the existing work,the recovery of strictly k-sparse signals with partial support information was derived in theℓ2 bounded noise setting.In this paper,the recovery of approximately k-sparse signals with partial support information in two noise settings is investigated via weightedℓp(0<p≤1)minimization method.The restricted isometry constant(RIC)conditionδt k<1 pη2 p−1+1 on the measurement matrix for some t∈[1+2−p 2+pσ,2]is proved to be sufficient to guarantee the stable and robust recovery of signals under sparsity defect in noisy cases.Herein,σ∈[0,1]is a parameter related to the prior support information of the original signal,andη≥0 is determined by p,t andσ.The new results not only improve the recent work in[17],but also include the optimal results by weightedℓ1 minimization or by standardℓp minimization as special cases. 展开更多
关键词 signal recovery weightedℓp minimization Approximately k-sparse signal Noise setting Reconstruction error bound Restricted isometry property
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自适应速度调整的限制人工驾驶模式应用研究
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作者 王钰 马铮 李业兴 《科学与信息化》 2024年第19期166-168,共3页
近年来,我国城市轨道交通蓬勃发展,信号系统作为城市轨道交通运营中的关键核心系统,一旦发生故障并降级运行,将严重降低运行效率、拉大运营间隔,如不能快速恢复正常运营模式或提高故障情况下的运营效率,将极大地影响运营质量,降低乘客... 近年来,我国城市轨道交通蓬勃发展,信号系统作为城市轨道交通运营中的关键核心系统,一旦发生故障并降级运行,将严重降低运行效率、拉大运营间隔,如不能快速恢复正常运营模式或提高故障情况下的运营效率,将极大地影响运营质量,降低乘客出行体验。因此,本文重点研究了一种自适应速度调整的限制人工驾驶模式(RM模式),其可在故障情况下以RM模式驾驶,在保证安全的前提下,快速提高列车运行速度,提高运营效率。 展开更多
关键词 限制人工驾驶模式 信号系统 城市轨道交通
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REQUIRED NUMBER OF ITERATIONS FOR SPARSE SIGNAL RECOVERY VIA ORTHOGONAL LEAST SQUARES
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作者 Haifeng Li Jing Zhang +1 位作者 Jinming Wen Dongfang Li 《Journal of Computational Mathematics》 SCIE CSCD 2023年第1期1-17,共17页
In countless applications,we need to reconstruct a K-sparse signal x∈R n from noisy measurements y=Φx+v,whereΦ∈R^(m×n)is a sensing matrix and v∈R m is a noise vector.Orthogonal least squares(OLS),which selec... In countless applications,we need to reconstruct a K-sparse signal x∈R n from noisy measurements y=Φx+v,whereΦ∈R^(m×n)is a sensing matrix and v∈R m is a noise vector.Orthogonal least squares(OLS),which selects at each step the column that results in the most significant decrease in the residual power,is one of the most popular sparse recovery algorithms.In this paper,we investigate the number of iterations required for recovering x with the OLS algorithm.We show that OLS provides a stable reconstruction of all K-sparse signals x in[2.8K]iterations provided thatΦsatisfies the restricted isometry property(RIP).Our result provides a better recovery bound and fewer number of required iterations than those proposed by Foucart in 2013. 展开更多
关键词 Sparse signal recovery Orthogonal least squares(OLS) Restricted isometry property(RIP)
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压缩感知中测量矩阵构造综述 被引量:24
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作者 王强 张培林 +2 位作者 王怀光 杨望灿 陈彦龙 《计算机应用》 CSCD 北大核心 2017年第1期188-196,共9页
压缩感知测量矩阵构造方式多样并不断发展,为梳理现有研究成果,掌握测量矩阵发展动态,对压缩感知测量矩阵构造进行系统介绍。首先,针对传统信号采集理论存在的信息冗余问题,阐述了压缩感知理论在信号采集过程中资源利用率高、存储空间... 压缩感知测量矩阵构造方式多样并不断发展,为梳理现有研究成果,掌握测量矩阵发展动态,对压缩感知测量矩阵构造进行系统介绍。首先,针对传统信号采集理论存在的信息冗余问题,阐述了压缩感知理论在信号采集过程中资源利用率高、存储空间小的优势;其次,以压缩感知理论框架为基础,从测量矩阵构造原则、测量矩阵产生方法、测量矩阵结构设计、测量矩阵优化方法四个方面,对压缩感知测量矩阵构造进行分析,讨论了测量矩阵构造过程中不同原则、结构、方法的优势;最后,在总结现有研究成果的基础上,对测量矩阵的发展方向进行了展望。 展开更多
关键词 压缩感知 测量矩阵 有限等距性质 信号重构 信号采集
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基于深度限制波尔兹曼机的辐射源信号识别 被引量:31
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作者 周东青 王玉冰 +2 位作者 王星 程相东 肖吉阳 《国防科技大学学报》 EI CAS CSCD 北大核心 2016年第6期136-141,共6页
针对电子侦察中使用常规参数难以有效识别复杂体制雷达信号的问题,提出利用深度限制波尔兹曼机对辐射源识别的模型。模型由多个限制波尔兹曼机组成,通过逐层自底向上无监督学习获得初始参数,并用后向传播算法对整个模型进行有监督的参... 针对电子侦察中使用常规参数难以有效识别复杂体制雷达信号的问题,提出利用深度限制波尔兹曼机对辐射源识别的模型。模型由多个限制波尔兹曼机组成,通过逐层自底向上无监督学习获得初始参数,并用后向传播算法对整个模型进行有监督的参数微调,利用Softmax进行分类识别。通过仿真实验表明该模型能对辐射源进行有效的特征提取和分类识别,具有较高的识别精度和较强的鲁棒性。 展开更多
关键词 辐射源信号识别 深度学习 限制波尔兹曼机
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