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Monitoring seismicity in the southern Sichuan Basin using a machine learning workflow
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作者 Kang Wang jie zhang +2 位作者 ji zhang zhangyu Wang Huiyu Zhu 《Earthquake Research Advances》 CSCD 2024年第1期59-66,共8页
Monitoring seismicity in real time provides significant benefits for timely earthquake warning and analyses.In this study,we propose an automatic workflow based on machine learning(ML)to monitor seismicity in the sout... Monitoring seismicity in real time provides significant benefits for timely earthquake warning and analyses.In this study,we propose an automatic workflow based on machine learning(ML)to monitor seismicity in the southern Sichuan Basin of China.This workflow includes coherent event detection,phase picking,and earthquake location using three-component data from a seismic network.By combining Phase Net,we develop an ML-based earthquake location model called Phase Loc,to conduct real-time monitoring of the local seismicity.The approach allows us to use synthetic samples covering the entire study area to train Phase Loc,addressing the problems of insufficient data samples,imbalanced data distribution,and unreliable labels when training with observed data.We apply the trained model to observed data recorded in the southern Sichuan Basin,China,between September 2018 and March 2019.The results show that the average differences in latitude,longitude,and depth are 5.7 km,6.1 km,and 2 km,respectively,compared to the reference catalog.Phase Loc combines all available phase information to make fast and reliable predictions,even if only a few phases are detected and picked.The proposed workflow may help real-time seismic monitoring in other regions as well. 展开更多
关键词 Earthquake monitoring Machine learning Local seismicity Gaussian waveform Sparse stations
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Supplementation with yak (Bos grunniens) bone collagen hydrolysate altered the structure of gut microbiota and elevated short-chain fatty acid production in mice 被引量:1
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作者 Zitao Guo Dalong Yi +9 位作者 Bo Hu Lingyu Zhu ji zhang Yuliang Yang Chunyu Liu Yi Shi Zhenghua Gu Yu Xin Huaigao Liu Liang zhang 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1637-1645,共9页
In this study, yak bone collagen hydrolysate(YBCH)was produced by mixed proteases and provided to standard-diet mice at a different dose(low dose(LD), medium dose(MD), and high dose(HD))to investigate its effects on t... In this study, yak bone collagen hydrolysate(YBCH)was produced by mixed proteases and provided to standard-diet mice at a different dose(low dose(LD), medium dose(MD), and high dose(HD))to investigate its effects on the composition of gut microbiota and short-chain fatty acids(SCFA)production. It was found that YBCH was mainly composed of small molecular peptides whose molecular weight below 2 000 Da. Notably, supplementation with different doses of YBCH could significantly downregulate the ratio of Firmicutes to Bacteroidetes in the fecal microbiota. At the family level, the Lachnospiraceae abundance was significantly reduced in the YBCH gavage groups(mean reduction ratio 41.7 %, 35.2%, and 36.4% for LD, MD, and HD group, respectively). The predicted functions of gut microbes in the MD group were significantly increased at “lipid metabolism” and “glycan biosynthesis and metabolism”. Moreover, the SCFA production in the YBCH groups was elevated. Especially, the concentration of acetic acid, propionic acid, and butyric acid in the MD group was separately increased 79.7%, 89.2%, and 78.8% than that in the NC group. These results indicated that YBCH might be applied in the development of functional food for intestinal microecological regulation. 展开更多
关键词 Yak bone collagen hydrolysate PEPTIDES Gut microbiota Short-chain fatty acid Lachnospiraceae
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非金属掺杂石墨烯异核双原子催化剂氮还原特性研究
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作者 张季 俞爱民 孙成华 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第9期263-270,共8页
氨是化肥、涂料等领域中重要的化工原料,是产量第二高的商用化学品.目前,90%以上的氨均来自Haber-Bosch法,该工艺需要高温高压,能耗高,且依赖化石燃料的使用,排放大量CO_(2),在倡导节能环保的新时代,该工艺面临严重的能耗及环保问题.电... 氨是化肥、涂料等领域中重要的化工原料,是产量第二高的商用化学品.目前,90%以上的氨均来自Haber-Bosch法,该工艺需要高温高压,能耗高,且依赖化石燃料的使用,排放大量CO_(2),在倡导节能环保的新时代,该工艺面临严重的能耗及环保问题.电催化氮还原合成氨(e NRR)是一种在常温常压条件下,采用电能作为驱动,以水和大气中的氮作为原料的新型绿色环保的合成氨方法,有望替代传统合成氨工艺.在eNRR过程中,电催化剂的催化活性和选择性是提高电催化合成氨的关键.目前,单原子催化剂(SAC)因其高原子利用率、高选择性等优点,在氧还原反应(ORR)、二氧化碳还原反应(CO_(2)RR)等方面得到广泛研究,但其在eNRR反应中表现不佳,因为单个金属原子位不能贡献足够多的电荷来活化惰性极强的N≡N键.据此,本文利用第一性原理计算,通过高通量筛选,系统研究了以非金属掺杂石墨烯为基质,以异核金属原子为反应位的双原子催化剂的氮还原特性及其微观催化机理.本文以B,S,P和N四种非金属元素与Fe,Co,Mo,W和Ru五种金属元素随机组成的40种催化剂M1M2-X做为催化剂模型,根据两步筛选,得到FeMo-S,RuMo-B,RuMo-P,RuMo-S和Ru W-S五种双原子催化剂,表现出优良的氮还原特性.与现有研究相比,五种双原子催化剂不但具有高催化活性(过电位为:FeMo-S(–0.18 V),RuMo-B(–0.25 V),RuMo-P(–0.27 V),RuMo-S(–0.29 V)和RuW-S(–0.24 V)),较高的热力学稳定性,而且可以有效抑制析氢(HER)反应.为了进一步与相应的单原子催化剂做比较,将单个金属原子键合于非金属元素掺杂的石墨烯基质上,形成17种M-X单原子催化剂.在同样的筛选机制下,只有Mo-P催化剂具有好的催化活性,但与HER的竞争劣势使其无法成为良好的催化剂.非金属原子调制的异核双原子催化剂对氮还原表现出良好的催化特性有其本质的原因.对双原子催化剂的电子特性进行研究,如Bader电荷、态密度、轨道哈密顿布居和电子差分密度等,结果表明,双原子催化剂的优良催化特性与下面几个方面有关:(1)金属双原子作为催化位点,可以提供更多的d电子,使其转移到氮气分子的反键轨道,从而活化N≡N键,两套d轨道也可以接纳更多的来自氮分子的孤对电子以增强吸附;(2)双原子的协同作用有效的调整了伴随金属原子的d带中心位置,中间吸附质的吸附自由能因此得到调节,从而改善了催化剂的催化性能;(3)不同种类的非金属元素的引入丰富了金属反应位的配体结构,使得催化剂对中间吸附质的吸附强度得到调节,从而降低了初始电位.综上,本文不仅分析了异核双原子催化剂性能,还从电子结构层面分析了NRR催化机理,为设计高性能催化剂提供一定借鉴.目前,电子结构的计算广泛应用于催化剂设计领域,它从电子结构层面深入理解催化机理,为催化剂设计,催化性能调控给出优化趋势.电催化是一个由多种因素共同影响的复杂化学过程,希望今后能够通过电子结构计算更加深入理解化学反应细节,能够对反应过程给出动力学分析,发现一般规律,设计出高性能NRR催化剂. 展开更多
关键词 电催化 双原子催化剂 石墨烯 氮还原反应 第一性原理
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The benefits of being smaller:Consistent pattern for climate-induced range shift and morphological difference of three falconiforme species
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作者 Aichun Xu ji zhang +2 位作者 Qian Li Zhongqiu Li Qin Zhu 《Avian Research》 SCIE CSCD 2023年第1期13-24,共12页
Climate exerts a dominant control over the distribution of species.Generally,species migrate to higher elevations to track thermal niches,but variations in morphological traits can result in trait-specific responses t... Climate exerts a dominant control over the distribution of species.Generally,species migrate to higher elevations to track thermal niches,but variations in morphological traits can result in trait-specific responses to climate change.Here we attempted to explore how three sympatrically distributed raptor species(the Upland Buzzard Buteo hemilasius,UB;the Common Kestrel,also called Eurasian Kestrel Falco tinnunculus,EK;and the Saker Falcon Falco cherrug,SF)would respond to climate change over time,and whether their responses would bias by different morphology.We tested the alternative hypotheses for Allen’s rule for UB,EK,and SF in Qinghai Province,China,by modeling their current and future habitat suitability and confirming whether a consistent pattern exists between climate-induced range shifts and morphological differences among species.The extent of the projected distribution range within protected areas was also calculated for each species.We identified the future downward elevation shift for all the species,but with the notable northeastward shifting of the suitable climate space for UB and SF.Climate change would induce range contraction in the future,and the most acute influence is always the result of the pessimistic SSP585 scenario.No obvious pattern in climate-induced range shift was found for EK,for whom the morphological traits were significantly smaller all the time.More seriously,the ratios of highly suitable habitats being protected for our three raptor species were almost at a deficient level(below 1%).This study firstly tested the alternative hypothesis of Allen’s rule among raptors in Qinghai Province unprecedently,confirmed the morphological basis for different responses to changing climate across species,and demonstrated the protection deficiency under the current protected area design.We advocate more related studies in the future to verify our findings across more taxa. 展开更多
关键词 Allen's rule Climate change Morphalogy Qinghai Province RAPTORS Range contraction
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Synthesis and Antioxidant Activity of(E)ω-Formylcamphene-Based Thiazole Hydrazone Derivatives
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作者 jiayu Chang Qingying Ding +9 位作者 Chong Zhong Yao Long Zhuanquan Xiao Hai Luo Yuling Yang Zongde Wang Shengliang Liao jinzhu Chen Shangxing Chen ji zhang 《Journal of Renewable Materials》 SCIE EI 2023年第1期379-391,共13页
(E)ω-formylcamphene was synthesized fromα-pinene,the main component of turpentine,and then reacted with thiosemicarbazide to obtain(E)ω-formylcamphene thiosemicarbazide 3,which was reacted with 14α-bromoace-tophen... (E)ω-formylcamphene was synthesized fromα-pinene,the main component of turpentine,and then reacted with thiosemicarbazide to obtain(E)ω-formylcamphene thiosemicarbazide 3,which was reacted with 14α-bromoace-tophenone compounds to obtain 14(E)ω-formylcamphene thiazole hydrazone compounds 5a–5n;the yields were all above 80%.The structures of the target compounds were characterized by IR,^(1)H-NMR,^(13)C-NMR,and HR-MS analyses.Then,500,250,125,62.5,and 31.25 mg/L drug solutions were prepared.Free radical scavenging experi-ments of 1,1-diphenyl-2-picrylhydrazyl(DPPH)and 2,2-bis(3-ethyl-benzothiazole-6-sulfonic acid)diammonium salt(ABTS)were carried out with Trolox and L-ascorbic acid as the control samples.The scavenging rates of 14 compounds for DPPH and ABTS free radicals were obtained;the IC_(50) values of scavenging free radicals were fitted using SPSS software.The results show that 14(E)ω-formylcamphene-based thiazole hydrazone compounds exhibited good scavenging effects on the two free radicals,especially when the concentration of the drug solution was 125 and 62.5 mg/L;most compounds exceeded the scavenging efficiency of Trolox and L-ascorbic acid. 展开更多
关键词 (E)ω-formylcamphene THIOSEMICARBAZONE thiazohydrazone structural analysis antioxidant activity
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UAMP-Based Delay-Doppler Channel Estimation for OTFS Systems
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作者 Zhongjie Li Weijie Yuan +2 位作者 Qinghua Guo Nan Wu ji zhang 《China Communications》 SCIE CSCD 2023年第10期70-84,共15页
Orthogonal time frequency space(OTFS)technique,which modulates data symbols in the delay-Doppler(DD)domain,presents a potential solution for supporting reliable information transmission in highmobility vehicular netwo... Orthogonal time frequency space(OTFS)technique,which modulates data symbols in the delay-Doppler(DD)domain,presents a potential solution for supporting reliable information transmission in highmobility vehicular networks.In this paper,we study the issues of DD channel estimation for OTFS in the presence of fractional Doppler.We first propose a channel estimation algorithm with both low complexity and high accuracy based on the unitary approximate message passing(UAMP),which exploits the structured sparsity of the effective DD domain channel using hidden Markov model(HMM).The empirical state evolution(SE)analysis is then leveraged to predict the performance of our proposed algorithm.To refine the hyperparameters in the proposed algorithm,we derive the update criterion for the hyperparameters through the expectation-maximization(EM)algorithm.Finally,Our simulation results demonstrate that our proposed algorithm can achieve a significant gain over various baseline schemes. 展开更多
关键词 orthogonal time frequency space(OTFS) channel estimation hidden Markov model(HMM) unitary approximate message passing(UAMP)
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Double-tract reconstruction is superior to esophagogastrostomy in controlling reflux esophagitis and enhancing quality of life after proximal gastrectomy:Results from a prospective randomized controlled clinical trial in China
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作者 Yinan zhang Hongtao zhang +10 位作者 Yan Yan Ke ji Ziyu jia Heli Yang Biao Fan Anqiang Wang Xiaojiang Wu ji zhang jiafu ji Xin ji Zhaode Bu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2023年第6期645-659,共15页
Objective:The aim of this study was to prospectively compare double-tract reconstruction(DTR)and esophagogastrostomy(EG)after proximal gastrectomy(PG)regarding the incidence of reflux esophagitis,quality of life(QOL),... Objective:The aim of this study was to prospectively compare double-tract reconstruction(DTR)and esophagogastrostomy(EG)after proximal gastrectomy(PG)regarding the incidence of reflux esophagitis,quality of life(QOL),nutritional status and surgical safety.Methods:This study was a randomized controlled trial.Patients eligible for PG were enrolled and randomly assigned to the EG group and DTR group.The characteristics of patients,parameters for surgical safety,incidence of reflux esophagitis,nutrition status and QOL were collected and compared between the two groups.Univariate analysis and multivariate analysis were performed to determine the significant factors affecting the incidence of reflux esophagitis after PG.Results:Thirty-seven patients of the EG group and 36 patients of the DTR group were enrolled.The incidence of reflux esophagitis was significantly lower in the DTR group than in the EG group(8.3%vs.32.4%,P=0.019).The DTR group demonstrated a more favorable QOL than the EG group after PG.The nutritional status was balanced within the EG group and the DTR group.The operation time was longer in the DTR group than in the EG group(191 min vs.221 min,P=0.001),while surgical safety was similar in the two groups.Conclusions:Our research demonstrated that DTR is superior to EG after PG in terms of the incidence of reflux esophagitis and provides a more satisfactory QOL without increasing surgical complications or sacrificing nutritional status. 展开更多
关键词 Double-tract reconstruction proximal gastrectomy quality of life reflux esophagitis
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使用内窥镜辅助眼眶骨折手术的疗效 被引量:5
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作者 张积 季晓燕 +3 位作者 解未青 张文 钱思程 徐国旭 《国际眼科杂志》 CAS 北大核心 2019年第4期687-689,共3页
目的:探讨内窥镜辅助下眼眶骨折手术整复效果。方法:回顾性分析2013-08/2016-08期间入我院就诊的眼眶骨折患者800例800眼,按照手术方式不同分为两组。其中354眼行鼻外径路手术,纳入对照组;446眼行内窥镜辅助下眼眶骨折手术,纳入观察组... 目的:探讨内窥镜辅助下眼眶骨折手术整复效果。方法:回顾性分析2013-08/2016-08期间入我院就诊的眼眶骨折患者800例800眼,按照手术方式不同分为两组。其中354眼行鼻外径路手术,纳入对照组;446眼行内窥镜辅助下眼眶骨折手术,纳入观察组。所有患者均完成术后6mo随访,观察患者术后临床疗效、复视分级、眼球凹陷改善情况,并评估患者术后随访对颜面部外形美观满意度。结果:术后3mo观察组总有效率为92.8%,对照组为90.4%(P>0.05);两组患者术前复视分级情况无差异(P>0.05),术后1mo观察组复视0级患者占70.9%,对照组占66.7%(P>0.05);术后6mo观察组复视0级所占比例显著高于对照组(97.1%vs 76.0%,P<0.05)。术前组间眼球内陷深度比较无差异(P>0.05);术后1mo眼球内陷深度≤1cm者:观察组占89.5%,对照组占85.9%(P>0.05);术后6mo,眼球内陷深度≤1cm,观察组97.3%明显高于对照组80.8%(P<0.05)。术后6mo时观察组对颜面部外观满意度为97.8%,明显高于对照组94.6%(P<0.05)。结论:内窥镜技术应用于眼眶骨折手术中可有效改善复视及眼球内陷情况,且长远疗效较好,术后恢复更符合现代人的审美要求。 展开更多
关键词 眼眶骨折 内窥镜辅助下手术 整复效果
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新冠肺炎疫情与百年未有之大变局下的国际秩序变革 被引量:14
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作者 张骥 《中央社会主义学院学报》 2020年第3期73-77,共5页
新冠疫情不仅仅是一次公共卫生危机,它还对世界各国和人类社会产生了全方位的重要影响。新冠疫情对国际关系和国际秩序的影响是在百年未有之大变局的国际格局下产生的,它不仅使得百年未有之大变局的特征在各个领域更加凸显出来,更是通... 新冠疫情不仅仅是一次公共卫生危机,它还对世界各国和人类社会产生了全方位的重要影响。新冠疫情对国际关系和国际秩序的影响是在百年未有之大变局的国际格局下产生的,它不仅使得百年未有之大变局的特征在各个领域更加凸显出来,更是通过疫情诱发的政治经济社会危机大大加剧和催化了百年未有之大变局。本文从权力结构、秩序结构、观念结构三个层面分析新冠疫情对国际秩序造成的重大影响,并前瞻在新冠疫情影响下国际秩序变革的未来走向。 展开更多
关键词 新冠疫情 百年未有之大变局 国际秩序
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铁路超长隧道安全风险管控及隐患排查治理监管 被引量:8
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作者 刘常军 傅鹤林 +3 位作者 翟筱松 张彦春 纪张 谢凤武 《中国安全科学学报》 CAS CSCD 北大核心 2020年第S01期21-26,共6页
为实现铁路超长隧道安全风险管理关口前移、风险隐患源头治理,在分析铁路超长隧道工程特征及主要安全风险的基础上,提出铁路超长隧道工程安全风险分级管控及隐患排查治理双重预防机制,创新构建"三单两线一平台"监管体系,并提... 为实现铁路超长隧道安全风险管理关口前移、风险隐患源头治理,在分析铁路超长隧道工程特征及主要安全风险的基础上,提出铁路超长隧道工程安全风险分级管控及隐患排查治理双重预防机制,创新构建"三单两线一平台"监管体系,并提出出台风险分级管控规范、安全风险管控监督指导意见、隐患排查治理实施细则、监督检查指南等制度建设措施。结果表明:建立双重预防机制有利于斩断风险因素传递链条,遏制重特大事故发生;完善政府监督体系及配套制度,有助于监督参建各方开展安全风险分级管控和隐患排查治理。 展开更多
关键词 铁路超长隧道 安全风险 隐患排查治理 风险分级管控 监管体系
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Neuroprotective effects of rutaecarpine on cerebral ischemia reperfusion injury 被引量:20
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作者 Chunlin Yan ji zhang +2 位作者 Shu Wang Guiping Xue Yong Hou 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第22期2030-2038,共9页
Rutaecarpine,an active component of the traditional Chinese medicine Tetradium ruticarpum,has been shown to improve myocardial ischemia reperfusion injury.Because both cardiovascular and cerebrovascular diseases are f... Rutaecarpine,an active component of the traditional Chinese medicine Tetradium ruticarpum,has been shown to improve myocardial ischemia reperfusion injury.Because both cardiovascular and cerebrovascular diseases are forms of ischemic vascular disease,they are closely related.We hypothesized that rutaecarpine also has neuroprotective effects on cerebral ischemia reperfusion injury.A cerebral ischemia reperfusion model was established after 84,252 and 504 μg/kg rutaecarpine were given to mice via intraperitoneal injection,daily for 7 days.Results of the step through test,2,3,5-triphenyl tetrazolium chloride dyeing and oxidative stress indicators showed that rutaecarpine could improve learning and memory ability,neurological symptoms and reduce infarction volume and cerebral water content in mice with cerebral ischemia reperfusion injury.Rutaecarpine could significantly decrease the malondialdehyde content and increase the activities of superoxide dismutase and glutathione peroxidase in mouse brain.Therefore,rutaecarpine could improve neurological function following injury induced by cerebral ischemia reperfusion,and the mechanism of this improvement may be associated with oxidative stress.These results verify that rutaecarpine has neuroprotective effects on cerebral ischemia reperfusion in mice. 展开更多
关键词 缺血再灌注损伤 神经保护作用 吴茱萸次碱 脑血管病 谷胱甘肽过氧化物酶 脑缺血再灌注 超氧化物歧化酶 心脑血管疾病
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Moxibustion eases chronic inflammatory visceral pain through regulating MEK, ERK and CREB in rats 被引量:12
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作者 Zhi-Yuan Li Yan Huang +9 位作者 Yan-Ting Yang Dan zhang Yan Zhao Jue Hong jie Liu Li-jie Wu Cui-Hong zhang Huan-Gan Wu ji zhang Xiao-Peng Ma 《World Journal of Gastroenterology》 SCIE CAS 2017年第34期6220-6230,共11页
AIM To investigate the effects of herb-partitioned moxibustion(HPM) on phosphorylation of mitogen-activated extracellular signal-regulated kinase(MEK)1, extracellular signal-regulated kinase(ERK)1/2 and c AMP response... AIM To investigate the effects of herb-partitioned moxibustion(HPM) on phosphorylation of mitogen-activated extracellular signal-regulated kinase(MEK)1, extracellular signal-regulated kinase(ERK)1/2 and c AMP response element binding protein(CREB) in spinal cord of rats with chronic inflammatory visceral pain(CIVP), and to explore the central mechanism of HPM in treating CIVP.METHODS Male Sprague-Dawley rats were randomized into normal, model, HPM, sham-HPM, MEK-inhibitor and dimethyl sulfoxide(DMSO) groups. The CIVP model was established using an enema mixture of trinitrobenzene sulfonic acid and ethanol. HPM was applied at bilateral Tianshu(ST25) and Qihai(CV6) acupoints in the HPM group, while in the sham-HPM group, moxa cones and herb cakes were only placed on the same points but not ignited. The MEK-inhibitor and DMSO groups received L5-L6 intrathecal injection of U0126 and 30% DMSO, respectively. Abdominal withdrawal reflex(AWR), mechanical withdrawal threshold(MWT) and thermal withdrawal latency(TWL) were applied for the assessment of pain behavior. The colonic tissue was observed under an optical microscope after hematoxylin-eosin staining. Expression of phosphor(p)MEK1, p ERK1/2 and p CREB in rat spinal cord was detected using Western blotting. The levels of MEK, ERK and CREB m RNA in rat spinal cord were detected using real-time polymerase chain reaction. RESULTS Compared with the normal group, the AWR scores were increased significantly(P < 0.01) and the MWT and TWL scores were decreased significantly(P < 0.05) in the model, sham-HPM and DMSO groups. Compared with the model group, the AWR scores were decreased significantly(P < 0.01) and the MWT and TWL scores were increased significantly in the HPM and MEK-inhibitor groups(P < 0.05). Compared with the sham-HPM and DMSO groups, the AWR scores were decreased significantly(P < 0.01) and the MWT and TWL scores were increased significantly(P < 0.05) in the HPM and MEK-inhibitor groups. Compared with the normal group, the expression of p MEK1, p ERK1/2 and p CREB proteins and the levels of MEK, ERK and CREB m RNA in rat spinal cord were increased significantly in the model, sham-HPM and DMSO groups(P < 0.01 or < 0.05). Compared with the model group, the expression of p MEK1, p ERK1/2 and p CREB proteins and the levels of MEK, ERK and CREB m RNA in rat spinal cord were reduced significantly in the HPM and MEK-inhibitor groups(P < 0.01 or < 0.05). Compared with the sham-HPM and DMSO groups, expression of p MEK1, p ERK1/2 and p CREB proteins and the levels of MEK, ERK and CREB m RNA in rat spinal cord were reduced significantly in the HPM and MEK-inhibitor groups(P < 0.01 or < 0.05). CONCLUSION HPM down-regulates protein phosphorylation of MEK1, ERK1/2 and CREB, and m RNA expression of MEK, ERK and CREB, inhibiting activation of the MEK/ERK/CREB signaling pathway in the spinal cord of CIVP rats, which is possibly a critical central mechanism of the analgesic effect of HPM. 展开更多
关键词 划分植物的艾灸 长期的煽动性的内脏的疼痛 疼痛行为 痛觉缺失 MEK 细胞外的调整信号的 kinase 营地反应元素绑定蛋白质 发信号的小径
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Construction and external validation of a nomogram that predicts lymph node metastasis in early gastric cancer patients using preoperative parameters 被引量:12
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作者 Yinan zhang Yiqiang Liu +7 位作者 ji zhang Xiaojiang Wu Xin ji Tao Fu Ziyu Li Qi Wu Zhaode Bu jiafu ji 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2018年第6期623-632,共10页
Objective: To create a nomogram to predict the incidence of lymph node metastasis(LNM) in early gastric cancer(EGC) patients and to externally validate the nomogram.Methods: To construct the nomogram,we retrospectivel... Objective: To create a nomogram to predict the incidence of lymph node metastasis(LNM) in early gastric cancer(EGC) patients and to externally validate the nomogram.Methods: To construct the nomogram,we retrospectively analyzed a primary cohort of 272 EGC patients.Univariate analysis and a binary logistic regression were performed.A nomogram predicting the incidence of LNM in EGC patients was created.The discrimination ability of the nomogram was measured using the concordance index(c-index),and the nomogram was also calibrated.Then,another prospective cohort of 81 patients was analyzed to validate the nomogram.Results: In the primary cohort,LNM was pathologically confirmed in 37(13.6%) patients.In multivariate analysis,the presence of an ulcer,the maximum lesion diameter observed via gastroscopy,the thickness of the lesion observed via endoscopic ultrasonography,and the presence of enlarged lymph nodes on computed tomography(CT) were independent risk factors for LNM.A nomogram was then created based on the regression model with the c-index of 0.905,and the calibration curve of the nomogram fell approximately on the ideal 45-degree line.The cut-off score of the nomogram was 110,and the sensitivity,specificity,positive predictive and negative predictive values of the nomogram in the primary cohort were 81.1%,86.0%,47.6% and 96.7%,respectively,and in the prospective validation cohort were 75.0%,91.0%,60.0% and 95.5%,respectively.The calibration curve of the external validation cohort was almost on the 45-degree line.Conclusions: We developed an effective nomogram predicting the incidence of LNM for EGC patients. 展开更多
关键词 Early GASTRIC cancer LYMPH NODE METASTASIS NOMOGRAM validation
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Herb-partitioned moxibustion alleviates colon injuries in ulcerative colitis rats 被引量:11
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作者 Dan zhang Yan-Bo Ren +7 位作者 Kai Wei Jue Hong Yan-Ting Yang Li-jie Wu ji zhang Zheng Shi Huan-Gan Wu Xiao-Peng Ma 《World Journal of Gastroenterology》 SCIE CAS 2018年第30期3384-3397,共14页
AIM To observe the effect of herb-partitioned moxibustion(HPM) on expression of colonic cytokines in ulcerative colitis(UC) rats.METHODS A UC rat model was established by protein immunization in combination with topic... AIM To observe the effect of herb-partitioned moxibustion(HPM) on expression of colonic cytokines in ulcerative colitis(UC) rats.METHODS A UC rat model was established by protein immunization in combination with topical chemical stimulation.Rats in the HPM group(n = 8) received HPM at bilateral Tianshu(ST25) points.The gross injury and pathological scores of the colon were recorded.The expression profile of colonic cytokines was assayed using the protein microarray technique.Specific differential cytokines were selected and verified by ELISA.The corresponding Uni Prot Accessions of the differentially expressed cytokines were retrieved in the Uni Prot database.The pathways involved were analyzed with the help of the KEGG PATHWAY database.The DAVID database was used for functional cluster and pathway analysis.RESULTS HPM improved colon injuries in UC rats,manifested by accelerated repair of ulcers and alleviation of inflammation,and the gross injury and pathological scores both significantly decreased(P < 0.01).Fold change > 1.3 or < 0.77 was taken as the screening standard.There were 77 down-regulated and 9 up-regulated differentially expressed colonic cytokines in the HPM group compared with the model group,and expression of 20 differed significantly(P < 0.05).Twelve of the 20 significantly differentially expressed cytokines [β-catenin,interleukin-1 receptor 6(IL-1 R6),IL-1β,B7-1,nerve growth factor receptor,AMP-activated protein kinase-α1,neuropilin-2,orexin A,adipocyte differentiation-related protein,IL-2,Fas and Fas L] were up-regulated in the model group(n = 3,compared with the normal group) but downregulated in the HPM group(n = 3,compared with the model group).Functional cluster analysis showed that the differentially expressed colonic cytokines in the HPM group regulated apoptosis and protein phosphorylation.KEGG pathway analysis showed that 52 down-regulated and 7 up-regulated differentially expressed colonic cytokines in the HPM group had pathways.The pathways that interacted between the cytokines and their receptors accounted for the largest proportion(28 of the downregulated and 5 of the up-regulated cytokines).CONCLUSION HPM promotes the repair of colon injuries in UC rats,which is related to the regulation of several abnormally expressed cytokines. 展开更多
关键词 Cytokine expression profile ULCERATIVE COLITIS Protein microarray RATS Herb-partitioned MOXIBUSTION
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Distribution and drug resistance of pathogenic bacteria isolated from cancer hospital in 2013 被引量:10
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作者 Linjuan Liu Qi Li +3 位作者 Qingyun zhang Guohong Wang Guobin Xu ji zhang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2014年第6期698-704,共7页
Objective: To understand distribution and drug resistance of pathogenic bacteria from a specialized cancer hospital in 2013 in order to provide a basis for rational clinical antimicrobial agents. Methods: Pathogenic b... Objective: To understand distribution and drug resistance of pathogenic bacteria from a specialized cancer hospital in 2013 in order to provide a basis for rational clinical antimicrobial agents. Methods: Pathogenic bacteria identification and drug sensitivity tests were performed with a VITEK 2 compact automatic identification system and data were analyzed using WHONET5.6 software.Results: Of the 1,378 strains tested, 980 were Gram-negative bacilli, accounting for 71.1%, in which Klebsiella pneumonia, Escherichia coli and Pseudomonas aeruginosa were the dominant strains. We found 328 Gram-positive coccus, accounting for 23.8%, in which the amount of Staphylococcus aureus was the highest. We identified 46 fungi, accounting for 4.1%. According to the departmental distribution within the hospital, the surgical departments isolated the major strains, accounting for 49.7%. According to disease types, lung cancer, intestinal cancer and esophagus cancer were the top three, accounting for 20.9%, 17.3% and 14.2%, respectively. No strains were resistant to imipenem, ertapenem or vancomycin.Conclusions: Pathogenic bacteria isolated from the specialized cancer hospital have different resistance rates compared to commonly used antimicrobial agents; therefore antimicrobial agents to reduce the morbidity and mortality of infections should be used. 展开更多
关键词 病原菌分离 肿瘤医院 耐药性 金黄色葡萄球菌 自动识别系统 革兰阴性杆菌 铜绿假单胞菌 抗菌药物
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绝缘纸特性和极性反转对油纸绝缘空间电荷效应的影响 被引量:14
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作者 李长云 冀章 闫宏伟 《中国电机工程学报》 EI CSCD 北大核心 2020年第14期4708-4718,共11页
油纸绝缘系统的空间电荷效应将畸变绝缘介质内部的电场,进一步影响其老化和击穿等电气特性。在直流电场、复合电场及极性反转等复杂工况下,换流变压器内绝缘系统的空间电荷效应将更为突出。基于双极性电荷输运模型,通过数值模拟方法探... 油纸绝缘系统的空间电荷效应将畸变绝缘介质内部的电场,进一步影响其老化和击穿等电气特性。在直流电场、复合电场及极性反转等复杂工况下,换流变压器内绝缘系统的空间电荷效应将更为突出。基于双极性电荷输运模型,通过数值模拟方法探究绝缘材料厚度、老化状态和极性反转等关键因素对空间电荷效应的影响。研究表明,绝缘纸厚度的变化不改变空间电荷密度曲线中正/负电荷区的极性偏移特性,但厚度变小缩短或消除了零电荷区;绝缘纸老化程度的加深,其电荷陷阱及深陷阱数目均会增多,这一方面加强了空间电荷效应的极性偏移,另一方面使得正电荷区呈变小趋势,从而使绝缘纸内电场畸变加剧;极性反转工况下,绝缘纸中陷阱电荷的脱陷或复合均需一定的时间滞后,使得净空间电荷密度曲线的负/正电荷区呈现初值不对称和沿介质厚度方向分布均不对称的特征,致使绝缘纸内部电场畸变愈发严重。研究结果可以为换流变压器油纸绝缘设计与防护提供参考。 展开更多
关键词 空间电荷效应 油纸绝缘 极性反转 陷阱理论 电场畸变
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Postoperative chemotherapy with S-1 plus oxaliplatin versus S-1alone in locally advanced gastric cancer(RESCUE-GC study): a protocol for a phase Ⅲ randomized controlled trial 被引量:5
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作者 Xiang Hu Lin Chen +29 位作者 Yian Du Biao Fan Zhaode Bu Xin Wang Yingjiang Ye Zhongtao zhang Gang Xiao Fei Li Qingsi He Guoli Li Xian Shen Bin Xiong Liming Zhu jiwei Liui Lian Liu Tao Wu jing Zhou Jun zhang Gang Zhao Xulin Wang Pin Liang Xinxin Wang Yan zhang Xiaojiang Wu ji zhang Xin ji Xianglong Zong Tao Fu Ziyu jia jiafu ji 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2017年第2期144-148,共5页
Background:The ACTS-GC study had shown postoperative adjuvant therapy with S-1 improved survival of patients with locally advanced gastric cancer.Addition of oxaliplatin to S-1 is considered to be acceptable as one of... Background:The ACTS-GC study had shown postoperative adjuvant therapy with S-1 improved survival of patients with locally advanced gastric cancer.Addition of oxaliplatin to S-1 is considered to be acceptable as one of the treatment options for gastric cancer patients after radical gastrectomy with D2 lymph node excision.Methods:We have commenced a randomized phase III trial in December 2016 to evaluate S-1 plus oxaliplatin compared with S-1 alone in the adjuvant setting for locally advanced gastric cancer.A total of 564 patients will be accrued from 13 Chinese institutions in two years.The primary endpoint is 3-year relapse-free survival.The secondary endpoints are 5-year overall survival,proportion of patients who complete the postoperative chemotherapy and incidence of adverse events.Ethic and dissemination:The trial has been approved by the institutional review board of each participating institution and it was activated on December,2016.The enrollment will be finished in December,2018.Patient’s follow-up will be ended until December,2023.Trial registration:Clinical Trials.gov,identifier:NCT02867839.Registered on August 4,2016. 展开更多
关键词 随机对照试验 奥沙利铂 S-1 III 胃癌 晚期 化疗 协议
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Epidemiologic characteristics of oral cancer:single-center analysis of 4097 patients from the Sun Yat-sen University Cancer Center 被引量:7
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作者 ji zhang Fan Gao +7 位作者 An-Kui Yang Wen-Kuan Chen Shu-Wei Chen Huan Li Xing zhang Zhong-Yuan Yang Xin-Lin Chen Ming Song 《Chinese Journal of Cancer》 SCIE CAS CSCD 2016年第4期190-195,共6页
Background:Oral cancer is a common type of head and neck cancers.Knowing its epidemiologic characteristics is crucial to preventing,diagnosing,and treating this cancer.This study aimed to explore the epidemiologic cha... Background:Oral cancer is a common type of head and neck cancers.Knowing its epidemiologic characteristics is crucial to preventing,diagnosing,and treating this cancer.This study aimed to explore the epidemiologic characteristics of oral cancer in South China.Methods:We retrospectively analyzed data from 4097 oral cancer patients treated at the Sun Yat-sen University Cancer Center between 1960 and 2013.We compared the age of onset,sex ratio,pathologic type,and primary tumor location among three subcultural areas(Guangfu,Hakka,and Chaoshan) and between an economically developed region and a less-developed one in Guangdong.Results:Overall,oral cancer had a male-to-female ratio of approximately 2:1,and this ratio decreased over time.Oral cancer occurred mostly in patients of 45-64 years old(54.5%),and the percentage of older patients gradually increased over time.The most common tumor location was the tongue.Squamous cell carcinoma was the predominant pathologic type.The percentage of blood type O in oral cancer patients was lower than that in the healthy population.The male-to-female ratio in the Chaoshan area was higher than that in the Guangfu and Hakka areas,whereas the age of disease onset in Guangfu was higher than that in Hakka and Chaoshan.The male-to-female ratio was lower and the age of disease onset was higher in the economically developed region than in the less-developed region.Conclusion:The incidence of oral cancer in South China presents typical characteristics to which doctors should pay attention when diagnosing and treating oral cancer patients. 展开更多
关键词 ORAL CANCER EPIDEMIOLOGY GUANGDONG
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Chrysophanol attenuates lead exposure-induced injury to hippocampal neurons in neonatal mice 被引量:4
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作者 ji zhang Chunlin Yan +3 位作者 Shu Wang Yong Hou Guiping Xue Li zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第9期924-930,共7页
Previous studies have shown that chrysophanol protects against learning and memory impairments in lead-exposed adult mice. In the present study, we investigated whether chrysophanol can alleviate learning and memory d... Previous studies have shown that chrysophanol protects against learning and memory impairments in lead-exposed adult mice. In the present study, we investigated whether chrysophanol can alleviate learning and memory dysfunction and hippocampal neuronal injury in lead-exposed neonatal mice. At the end of lactation, chrysophanol(0.1, 1.0, 10.0 mg/kg) was administered to the neonatal mice by intraperitoneal injection for 15 days. Chrysophanol significantly alleviated injury to hippocampal neurons and improved learning and memory abilities in the lead-poisoned neonatal mice. Chrysophanol also significantly decreased lead content in blood, brain, heart, spleen, liver and kidney in the lead-exposed neonatal mice. The levels of malondialdehyde in the brain, liver and kidney were significantly reduced, and superoxide dismutase and glutathione peroxidase activities were significantly increased after chrysophanol treatment. Collectively, these findings indicate that chrysophanol can significantly reduce damage to hippocampal neurons in lead-exposed neonatal mice. 展开更多
关键词 海马神经元 神经元损伤 成年小鼠 大黄酚 铅暴露 新生 学习记忆能力 谷胱甘肽过氧化物酶
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Molecular interaction mechanism in the separation of a binary azeotropic system by extractive distillation with ionic liquid 被引量:4
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作者 Hong Li Guanlun Sun +5 位作者 Dongyang Li Li Xi Peng Zhou Xingang Li ji zhang Xin Gao 《Green Energy & Environment》 SCIE CSCD 2021年第3期329-338,共10页
Ionic liquids(ILs)have shown excellent performance in the separation of binary azeotropes through extractive distillation[1].But the role of the ionic liquid in azeotropic system is not well understood.In this paper,C... Ionic liquids(ILs)have shown excellent performance in the separation of binary azeotropes through extractive distillation[1].But the role of the ionic liquid in azeotropic system is not well understood.In this paper,COSMO-RS model was applied to screen an appropriate IL to separate the binary azeotrope of ethyl acetate(EA)and ethanol and 1-octyl-3-methylimidazolium tetrafluoroborate([OMIM][BF4])was selected.The Quantum Mechanics(QM)calculations and molecular dynamics(MD)simulation are performed to study the interactions between the solvent molecules and[OMIM][BF4],in order to investigate the separation mechanism at the molecular level.The nature of the interactions is studied through the reduced density gradient(RDG)function and quantum theory of Atom in Molecule(QTAIM).Hydrogen bonds and van der Waals interactions are the key interactions in the complexes.The results of MD simulations indicate that the introduction of ILs has a prominent effect on the interaction between the solvent molecules,especially on reducing the number of hydrogen bonds among the solvent molecules.The radial distribution function(RDF)reveals that the interaction between the cation and solvent molecules will increase while the concentration of ILs increases.This paper provides important information for understanding the role of ILs in the separation of the azeotropic system,which is valuable to the development of new entrainers. 展开更多
关键词 Ionic liquids AZEOTROPE Density functional theory SEPARATION Extractive distillation
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