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Bipartite consensus problems of Lurie multi-agent systems over signed graphs: A contraction approach
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作者 张晓娇 吴祥 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期137-145,共9页
This paper examines the bipartite consensus problems for the nonlinear multi-agent systems in Lurie dynamics form with cooperative and competitive communication between different agents. Based on the contraction theor... This paper examines the bipartite consensus problems for the nonlinear multi-agent systems in Lurie dynamics form with cooperative and competitive communication between different agents. Based on the contraction theory, some new conditions for the nonlinear Lurie multi-agent systems reaching bipartite leaderless consensus and bipartite tracking consensus are presented. Compared with the traditional methods, this approach degrades the dimensions of the conditions, eliminates some restrictions of the system matrix, and extends the range of the nonlinear function. Finally, two numerical examples are provided to illustrate the efficiency of our results. 展开更多
关键词 contraction theory virtual system bipartite consensus Lurie multi-agent systems
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Allocation of Public Service Facilities in Villages and Towns from the Perspective of Smart Contraction: A Case Study of Zixi County, Jiangxi Province
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作者 ZHANG Xiaoli 《Journal of Landscape Research》 2024年第5期56-58,共3页
The limitation of traditional layout system and the continuous contraction of villages and towns have brought challenges to the layout of public service facilities.It is an imperative task against this background to i... The limitation of traditional layout system and the continuous contraction of villages and towns have brought challenges to the layout of public service facilities.It is an imperative task against this background to integrate space resources and allocate public service facilities scientifically and reasonably.This paper took the system and method of rural public service facility allocation from the perspective of smart contraction as the theoretic support,and Zixi County in Jiangxi Province for example,built the four-level life circle of“county-fundamental-basic-routine”based on the influence factors of facility allocation,village and town contraction strength,rural comprehensive assessment results,residents’trip willingness and demands on public service facilities,finally proposed the suggestions for optimizing the allocation of village and town public service facilities. 展开更多
关键词 Smart contraction Village and town Public service facility Allocation research Zixi County
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Revisiting the Electron Radius in Light of Length Contraction
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作者 Julie Marty 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1743-1748,共6页
In previous work, the electron radius was identified as the “actual electron radius.” However, this is more accurately described as the electron radius at rest. This study reexamines the electron with an emphasis on... In previous work, the electron radius was identified as the “actual electron radius.” However, this is more accurately described as the electron radius at rest. This study reexamines the electron with an emphasis on the electron radius under motion, incorporating the effects of length contraction. The findings suggest that the radius is subject to Lorentz contraction, which has interesting implications for relativistic effects at the subatomic level. 展开更多
关键词 Electron Radius Length contraction Lorentz Factor Relativistic Effects Subatomic Particles Compton Scattering
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DIRECTED HYPERGRAPH THEORY AND DECOMPOSITION CONTRACTION METHOD
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作者 黄汝激 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1995年第2期123+114-123,共11页
A new branch of hypergraph theory-directed hyperaph theory and a kind of new methods-dicomposition contraction(DCP, PDCP and GDC) methods are presented for solving hypernetwork problems.lts computing time is lower tha... A new branch of hypergraph theory-directed hyperaph theory and a kind of new methods-dicomposition contraction(DCP, PDCP and GDC) methods are presented for solving hypernetwork problems.lts computing time is lower than that of ECP method in several order of magnitude. 展开更多
关键词 directed hypergraph theory decomposition contraction method hypernetwork
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论农业适度规模经营视野下的承包地细碎化治理
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作者 高圣平 《武汉大学学报(哲学社会科学版)》 北大核心 2025年第1期160-171,共12页
发展农业适度规模经营是中国式农业农村现代化的必由之路,而承包地细碎化治理是发展农业适度规模经营中的关键一环。承包地细碎化治理模式中,“承包权不动,经营权连片”在法律上的技术路径是三权分置之下的土地经营权流转;“承包权互换... 发展农业适度规模经营是中国式农业农村现代化的必由之路,而承包地细碎化治理是发展农业适度规模经营中的关键一环。承包地细碎化治理模式中,“承包权不动,经营权连片”在法律上的技术路径是三权分置之下的土地经营权流转;“承包权互换,承包地连片”在法律上的技术路径是两权分离之下的土地承包经营权互换。农村集体经济组织在承包地细碎化治理中发挥着统筹协调、组织服务等功能,按照法定的程序形成集体意志,还可以充当承包农户在土地经营权外部流转时的代理人,以破除集体行动困境。承包地的调整仅限于个别农户之间,并在符合法定条件的前提之下按照法定程序进行,不得以承包地细碎化治理为由扩大承包地调整的适用范围而进行“打乱重分”。 展开更多
关键词 农业适度规模经营 承包地细碎化 农村集体经济组织 承包地调整 农地“三权分置” 土地承包经营权 党的二十届三中全会精神
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农村地区高血压患者服药情况及影响因素研究:基于家庭医生签约服务
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作者 马晓燕 崔恩慈 +5 位作者 薛群 刘荣 张学武 王浅 王德斌 沈兴蓉 《中国全科医学》 CAS 北大核心 2025年第3期365-371,共7页
背景高血压是心血管疾病主要的危险因素,降压用药不仅要考虑患者血压特征,也要考虑患者合并症情况。现阶段,基于家庭医生签约服务对高血压患者的服药状况及影响因素研究比较缺乏。目的调查安徽省界首市家庭医生签约服务的高血压患者服... 背景高血压是心血管疾病主要的危险因素,降压用药不仅要考虑患者血压特征,也要考虑患者合并症情况。现阶段,基于家庭医生签约服务对高血压患者的服药状况及影响因素研究比较缺乏。目的调查安徽省界首市家庭医生签约服务的高血压患者服药现状,描述患者服药行为与患者特征之间的关联,探索患者用药调整的影响因素,并分析基层高血压患者用药的合理性。方法采用整群抽样的方法,于2021年7—8月从安徽省界首市随机抽取48个行政村,通过面对面调查法采用自制问卷收集患者特征和服药数据,参照《国家基层高血压防治管理指南2020版》将问卷中患者提到的降压药分为如下5类:A类为血管紧张素转换酶抑制剂(ACEI)和血管紧张素受体阻滞剂(ARB),B类为β受体阻滞剂,C类为钙通道阻滞剂(CCB),D类为利尿剂,E类为单片复方制剂。通过科大讯飞智能语音血压计的后台获取患者上传的近1年血压数据,分析不同特征患者的服药行为。采用多因素Logistic回归分析探讨高血压患者用药调整的影响因素。本研究中联合用药是指服用复方制剂或2种以上降压药,用药调整是指患者过去服用其他降压药。结果本研究共纳入高血压患者3005例,其中男1291例(43.0%)、女1714例(57.0%),平均年龄为(65.5±9.8)岁,高血压服药率为79.1%,联合用药率为40.2%。2376例服用降压药的患者中,不同类型降压药服用率从高到低依次为(部分患者存在联合用药):E类(39.6%)、C类(35.1%)、D类(20.3%)、A类(20.1%)、B类(3.7%);服用最多的降压药为复方利血平(33.7%)。对于年均血压≥160/100mm Hg的患者,仍有12.2%和4.9%未服用降压药。患者联合用药以E类降压药为主。年均“舒张压≥100 mm Hg”且“患合并症”的患者,调整后A类和C类降压药的服用率增加相对较多,年均“收缩压≥160 mm Hg”且“未患合并症”的患者,调整后E类降压药的服用率增加相对较多。多因素Logistic回归结果显示,服药年数长(OR=1.042,95%CI=1.031~1.053,P<0.001)、初中以上文化程度(OR=1.488,95%CI=1.195~1.853,P<0.001)、合并高脂血症(OR=1.267,95%CI=1.052~1.525,P=0.013)、合并心血管疾病(OR=1.394,95%CI=1.166~1.667,P<0.001)、合并脑血管疾病(OR=1.258,95%CI=1.040~1.522,P=0.018)是患者用药调整的促进因素,高龄(OR=0.980,95%CI=0.971~0.990,P<0.001)是用药调整的抑制因素。结论界首市农村地区高血压患者的服药率较高,主要服用E类和C类降压药。服药年数长、初中以上文化程度、合并高脂血症、合并心脑血管疾病是患者用药调整的促进因素,高龄是用药调整的抑制因素。 展开更多
关键词 高血压 抗高血压药 合并症 联合用药 农村地区 界首 家庭医生签约服务
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基于混合语义的切片级智能合约重入漏洞检测
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作者 江姝晨 牛保宁 高彦 《计算机工程与应用》 北大核心 2025年第1期321-329,共9页
针对现有基于深度学习的漏洞检测方法主要集中在源代码的单一表现形式上,无法完全捕获源代码中包含的丰富语义信息和结构信息,以及大多数方法基于函数粒度,检测样本存在大量与漏洞无关的冗余代码导致检测精度下降的问题,聚焦于智能合约... 针对现有基于深度学习的漏洞检测方法主要集中在源代码的单一表现形式上,无法完全捕获源代码中包含的丰富语义信息和结构信息,以及大多数方法基于函数粒度,检测样本存在大量与漏洞无关的冗余代码导致检测精度下降的问题,聚焦于智能合约最严重的漏洞之一,即重入漏洞,提出一种基于混合语义的切片级智能合约重入漏洞检测方法SCHyVulDect。根据漏洞特征关键字对智能合约进行切片操作,获得合约切片;构建合约切片的代码图,通过图注意力网络(graph attention network,GAT)提取其深层语义信息。并使用双向长短期记忆网络(bidirectional long-short term memory,Bi-LSTM)和注意力机制,提取切片代码的上下文序列特征,将提取的图结构特征和序列特征进行融合,从而进行漏洞检测。实验结果表明,SCHyVulDect检测重入漏洞的精确率、召回率和F1值分别为96.36%、94.45%、91.70%,比现有的基于深度学习的智能合约漏洞检测方法的精确率提高13.03~18.00个百分点,具有较好的检测效果。 展开更多
关键词 区块链 智能合约 漏洞检测 图注意力网络 混合语义
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中医药诊治室性早搏研究进展
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作者 黄一婷 曾建斌 《亚太传统医药》 2025年第1期223-227,共5页
室性早搏是最常见的心律失常之一,患者可有心悸、胸闷、乏力、心跳停搏感,甚至黑矇晕厥、诱发心绞痛,严重者发生心源性猝死。通过查阅、整理与分析中医药诊治室性早搏的文献,可将其归属于中医学“心悸”“惊悸”“怔忡”等范畴,室性早... 室性早搏是最常见的心律失常之一,患者可有心悸、胸闷、乏力、心跳停搏感,甚至黑矇晕厥、诱发心绞痛,严重者发生心源性猝死。通过查阅、整理与分析中医药诊治室性早搏的文献,可将其归属于中医学“心悸”“惊悸”“怔忡”等范畴,室性早搏病位在心,与肾、肝、脾、肺关系密切,病机不外乎虚实两端,气血阴阳亏虚,心失所养;痰饮瘀火扰心,心神不宁。室性早搏的分型虽尚未统一,但主要可分为气阴两虚证、肝郁气滞证、气阴两虚夹瘀证、气血两虚证等。中医药治疗室性早搏采用口服中药为主,针刺、揿针、穴位贴敷等中医特色疗法为辅,使其阴平阳秘,心神安宁。 展开更多
关键词 室性早搏 中医药 心悸
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我国农村家庭医生签约服务老年人健康管理实践影响因素:一项范围综述
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作者 刘海燕 宁艳花 +5 位作者 孔维娟 郭亚红 史晶 柳玲娜 吕兄兄 李美曼 《中国全科医学》 CAS 北大核心 2025年第4期482-490,共9页
背景以家庭医生签约服务为载体的健康管理服务是我国农村老年人实现健康老龄化的必要途径,而该项服务在实践中受到多种因素影响。目的对影响我国农村家庭医生签约服务老年人健康管理实践的因素进行范围综述,为提高该项服务的可及性和有... 背景以家庭医生签约服务为载体的健康管理服务是我国农村老年人实现健康老龄化的必要途径,而该项服务在实践中受到多种因素影响。目的对影响我国农村家庭医生签约服务老年人健康管理实践的因素进行范围综述,为提高该项服务的可及性和有效性提供参考依据。方法于2023年1—4月,遵循范围综述报告规范清单,于Web of Science、PubMed、Embase、Medline、CINAHL、中国知网、万方数据知识服务平台、维普网和中国生物医学文献数据库检索有关家庭医生签约服务老年人健康管理的文献,检索时限为建库至2022-12-31。根据纳入和排除标准,基于社会生态学模型审查、总结和分析影响农村家庭医生签约服务老年人健康管理实践的因素。结果共纳入27篇文献,提取了与农村家庭医生签约服务老年人健康管理相关的个人、人际、组织、社区及政策5个层面的影响因素。结论农村家庭医生签约服务老年人健康管理实践受到多层面、多因素影响,推动农村地区签约服务老年人健康管理发展需综合考虑其影响因素,明确各责任部门、主体的权利和义务,合力促进以家庭医生签约服务为载体的健康管理服务提质增效。 展开更多
关键词 全科医生 家庭医生签约服务 乡村卫生服务 老年人 人口健康管理
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基于数据流图和混合网络模型的智能合约漏洞检测
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作者 丁诗琪 陈正奎 黄海 《软件工程》 2025年第1期52-56,共5页
智能合约控制着区块链上巨额资产的流动,因此确保其安全性至关重要。基于此,提出一种基于数据流图和混合深度学习模型的方法,即DFG-HDP,用于检测智能合约的漏洞。该方法首先对智能合约源码进行清洗和变量规范;其次从源码中提取数据流特... 智能合约控制着区块链上巨额资产的流动,因此确保其安全性至关重要。基于此,提出一种基于数据流图和混合深度学习模型的方法,即DFG-HDP,用于检测智能合约的漏洞。该方法首先对智能合约源码进行清洗和变量规范;其次从源码中提取数据流特征,将其与源码结合作为输入;最后将不同的词嵌入模型与不同的深度学习模型结合,对输入进行学习检测。实验结果表明,该方法在智能合约漏洞检测中的F1值高达89.90%,优于之前的漏洞检测方法CBGRU。这一结果证明了该方法的有效性和优越性。 展开更多
关键词 智能合约 漏洞检测 数据流图 混合模型
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A Graphlike Manifold Whose Contraction is 被引量:1
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作者 刘晓真 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期76-77,共2页
For a graphlike manifold whose contraction is a generalized cuneate figure,we deribve a formula in this paper to compute the number of homeomorphism classes of it by using twist operations and the combinatorial theory.
关键词 contraction negative edges twist operation
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Thick-skinned Contractional Salt Structures in the Kuqa Depression,the Northern Tarim Basin:Constraints from Physical Experiments 被引量:17
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作者 YU Yixin TANG Liangjie +3 位作者 YANG Wenjing JIN Wenzheng PENG Gengxin LEI Ganglin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第2期327-333,共7页
Thick-skinned contractional salt structures are widely developed in the western Kuqa depression, northern Tarim basin. To understand the mechanisms that govern the development of these structures, physical experiments... Thick-skinned contractional salt structures are widely developed in the western Kuqa depression, northern Tarim basin. To understand the mechanisms that govern the development of these structures, physical experiments are conducted and the results show that they are largely governed by the activities of basement faults and the forming of paleo-uplifts and basement slopes. The model materials in this study are dry sand, vaseline and plasticene (or hard foam), simulating the suprasalt, salt, and subsalt layers respectively. The experiments show that, due to the activities of basement faults and the forming of the paleo-uplifts, salt bodies usually accumulate and thicken significantly on the middle top of the paleo-uplifts which are constrained by the pre-exiting boundary faults. The development of large-scale thrust faults and salt nappes is favored by the basement slops with larger dips. The experiments also conclude that differential structural deformation could occur between the subsalt and suprasalt layers because of the presence of salt layers. Their geometries and the locations of structural highs are different, despite of the great similarities in the uplifted areas. The pierced salt diapir is not observed in the experiments, which indicates that the contractional shortening does not effectively accelerate the development of the salt diapir. 展开更多
关键词 thick-skinned contraction basement structures salt structures physical modeling Kuqa depression
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Effect of areca on contraction of colonic muscle strips in rats 被引量:20
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作者 Dong-Ping Xie Lian-Bi Chen,Department of Physiology,Medical College,Shandong University,Jinan 250012,Shandong Province,China Wei Li Song-Yi Qu Tian-Zhen Zheng,Department of Physiology,Lanzhou Medical College,Lanzhou 730000,Gansu Province,China Ying-Li Yang,Northwest Normal University,Lanzhou 730070,Gansu Province,China Yong-Hui Ding Yu-Ling Wei,Drug Control Institute of Gansu Province,Lanzhou 730000,Gansu Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期350-352,共3页
AIM: To investigate the effects of areca on the contractile activity of isolated colonic muscle strips in rats and mechanism involved. METHODS: Each strip (LMPC, longitudinal muscle of proximal colon; CMPC, circular m... AIM: To investigate the effects of areca on the contractile activity of isolated colonic muscle strips in rats and mechanism involved. METHODS: Each strip (LMPC, longitudinal muscle of proximal colon; CMPC, circular muscle of proximal colon; LMDC, longitudinal muscle of distal colon; CMDC, circular muscle of distal colon.) was suspended in a tissue chamber containing 5 mL Krebs solution (37 degrees C), bubbled continuously with 950 mL.L(-1) O(2) and 50 mL.L(-1) CO(2). The mean contractile amplitude (A), the resting tension (T), and the contractile frequency (F) were simultaneously recorded on recorders. RESULTS: Areca dose dependently increased the mean contractile amplitude, the resting tension of proximal and distal colonic smooth muscle strips in rats (P【0.05). It also partly increased the contractile frequency of colonic smooth muscle strips in rats (P【0.05). The effects were partly inhibited by atropine (the resting tension of LMPC decreased from 0.44 +/- 0.12 to 0.17 +/- 0.03; the resting tension of LMDC decreased from 0.71 +/- 0.14 to 0.03 +/- 0.01; the mean contractile amplitude of LMPC increased from -45.8 +/- 7.2 to -30.5 +/- 2.9; the motility index of CMDC decreased from 86.6 +/- 17.3 to 32.8 +/- 9.3; P【0.05 vs areca), but the effects were not inhibited by hexamethonium (P】0.05). CONCLUSION: Areca stimulated the motility of isolated colonic smooth muscle strips in rats. The stimulation of areca might be relevant with M receptor partly. 展开更多
关键词 ARECA Animals ATROPINE Colon Female Hexamethonium In Vitro Male Muscle contraction Nicotinic Antagonists Parasympatholytics Plant Extracts RATS Rats Wistar Research Support Non-U.S. Gov't
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Metformin attenuates motility,contraction,and fibrogenic response of hepatic stellate cells in vivo and in vitro by activating AMP-activated protein kinase 被引量:11
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作者 Zhen Li Qian Ding +4 位作者 Li-Ping Ling Ying Wu Dong-Xiao Meng Xiao Li Chun-Qing Zhang 《World Journal of Gastroenterology》 SCIE CAS 2018年第7期819-832,共14页
AIM To investigate the effect of metformin on activated hepatic stellate cells(HSCs) and the possible signaling pathways involved. METHODS A fibrotic mouse model was generated by intraperitoneal injection of carbon te... AIM To investigate the effect of metformin on activated hepatic stellate cells(HSCs) and the possible signaling pathways involved. METHODS A fibrotic mouse model was generated by intraperitoneal injection of carbon tetrachloride(CCl_4) and subsequent treatment with or without metformin. The level of fibrosis was detected by hematoxylin-eosin staining, Sirius Red staining, and immunohistochemistry. The HSC cell line LX-2 was used for in vitro studies. The effect of metformin on cell proliferation(CCK8 assay),motility(scratch test and Transwell assay), contraction(collagen gel contraction assay), extracellular matrix(ECM) secretion(Western blot), and angiogenesis(ELISA and tube formation assay) was investigated. We also analyzed the possible signaling pathways involved by Western blot analysis.RESULTS Mice developed marked liver fibrosis after intraperitoneal injection with CCl_4 for 6 wk. Metformin decreased the activation of HSCs, reduced the deposition of ECM, and inhibited angiogenesis in CCl_4-treated mice. Platelet-derived growth factor(PDGF) promoted the fibrogenic response of HSCs in vitro, while metformin inhibited the activation, proliferation, migration, and contraction of HSCs, and reduced the secretion of ECM. Metformin decreased the expression of vascular endothelial growth factor(VEGF) in HSCs through inhibition of hypoxia inducible factor(HIF)-1α in both PDGF-BB treatment and hypoxic conditions, and it down-regulated VEGF secretion by HSCs and inhibited HSC-based angiogenesis in hypoxic conditions in vitro. The inhibitory effects of metformin on activated HSCs were mediated by inhibiting the Akt/mammalian target of rapamycin(m TOR) and extracellular signal-regulated kinase(ERK) pathways via the activation of adenosine monophosphate-activated protein kinase(AMPK).CONCLUSION Metformin attenuates the fibrogenic response of HSCs in vivo and in vitro, and may therefore be useful for the treatment of chronic liver diseases. 展开更多
关键词 hepatic stellate cell INTRAHEPATIC vascular resistance angiogenesis contraction liver fibrosis ADENOSINE monophosphate-activated protein kinase
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Mechanisms mediating CCK-8S-induced contraction of proximal colon in guinea pigs 被引量:8
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作者 Zhu, Jie Chen, Ling +1 位作者 Xia, Hong Luo, He-Sheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第9期1076-1085,共10页
AIM:To investigate the effects of sulfated cholecystokinin octapeptide (CCK-8S) on the contractile activity of guinea-pig proximal colon.METHODS:Proximal colonic smooth muscle (PCSM) strips were obtained from adult fe... AIM:To investigate the effects of sulfated cholecystokinin octapeptide (CCK-8S) on the contractile activity of guinea-pig proximal colon.METHODS:Proximal colonic smooth muscle (PCSM) strips were obtained from adult female guinea pigs and contractile response of PCSM strips was recorded using a polyphysiograph.PCSM cells were isolated by enzymatic digestion.Resting potential (RP),action potential (AP),large conductance potassium channel currents (IBKCa) and L-type calcium currents (ICa-L) were recorded by patch-clamp techniques.RESULTS:(1) CCK-8S (10-7 mol/L) enhanced the mean contractile amplitude of colonic circular muscle and longitudinal muscle (LM) strips by 56.53% ± 11.92%(P=0.038) and 65.93% ± 12.98% (P=0.019),respectively,as well as the mean frequency of LM by 31.69% ± 13.58% (P=0.023),which were significantly attenuated by pretreating strips with devazepide,nifedipine,iberiotoxin,thapsigargin (TG) and BAPTA-AM (BA) respectively;(2) CCK-8S (10-7 mol/L) increased the AP amplitude by 38.6% ± 3.2% (P=0.015),decreased AP duration by 36.9% ± 8.7% (P=0.026),and depolarized the RP from-61.3 ± 2.7 mV to-29.8 ± 5.9 mV (P=0.032);and (3) Compared with the normal control group,CCK-8S (10-7 mol/L) enhanced the peak current of IBKCa by 18.7% ± 2.1% (from 916 ± 183 pA to 1088 ± 226 pA;at +60 mV;P=0.029),which was inhibited by respective pretreatment with iberiotoxin and devazepide.Additionally,CCK-8S (10-7 mol/L) intensif ied the peak current of ICa-L by 40% (from 60 ± 8 pA to 84 ± 11 pA;at +10 mV;P=0.012),compared to the normal control group,which was apparently suppressed by respective pretreatment with nifedipine,devazepide,TG and BA.In the respective presence of heparin and staurosporine,CCK-8S did not signif icantly enhance IBKCa and ICa-L.CONCLUSION:The results suggest that CCK-8S promotes guinea-pig proximal colon contraction by CCK1 receptors,following activation of the inositol triphosphate-protein kinase C signal transduction pathway. 展开更多
关键词 Muscle contraction Potassium CHANNELS Calcium CHANNELS COLON CHOLECYSTOKININ OCTAPEPTIDE
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Rapid bilateral anterior capsule contraction following high myopic cataract surgeries:a case report 被引量:9
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作者 Wei Xiao Dai-Xin Zhao and Long-Quan Xue 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2011年第2期207-209,共3页
We describe a rapid anterior capsule contraction following phacoemulsifiction and intraocular lens(IOL) implantation in an old woman with high myopia. The patient with high myopia complicated with cataract received ph... We describe a rapid anterior capsule contraction following phacoemulsifiction and intraocular lens(IOL) implantation in an old woman with high myopia. The patient with high myopia complicated with cataract received phacoemulcification and IOL implantation bilaterally .The best-corrected visual acuity (BCVA) improved from 0.1 to 0.4 in the right eye and 0.5 in the left eye 1 week after surgeries.5 weeks after surgery of the right eye and 4 weeks after surgery of the left eye, the patient complained blurred vision in the right eye. BCVA of the right eye was 0.06 and that of the left was 0.1. Slit-lamp examination revealed anterior capsule contraction in both eyes and a fully closed capsulorhexis opening in the right eye. The IOLs were centered but almost completely enclosed, with numerous linear fibrous folds radiating from the hick central fibrosis. We surgically excised the central part of the anterior capsule of the eyes with microscissors, resulting again in BCVA of 0.4 and 0.5 in the right and left eyes respectively. Anterior capsule contraction might appear much earlier than three months after phacoemulsification and IOL implantation surgery in case of high myopia complicated with cataract. Patients with high myopia receive cataract and IOL surgery should be monitored carefully for the rapid development of anterior capsule contraction. 展开更多
关键词 high myopia CATARACT PHACOEMULSIFICATION anterior capsule contraction
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sEMG Feature Analysis on Forearm Muscle Fatigue During Isometric Contractions 被引量:9
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作者 明东 王欣 +6 位作者 徐瑞 邱爽 赵欣 綦宏志 周鹏 张力新 万柏坤 《Transactions of Tianjin University》 EI CAS 2014年第2期139-143,共5页
In order to detect and assess the muscle fatigue state with the surface electromyography(sEMG) characteristic parameters,this paper carried out a series of isometric contraction experiments to induce the fatigue on th... In order to detect and assess the muscle fatigue state with the surface electromyography(sEMG) characteristic parameters,this paper carried out a series of isometric contraction experiments to induce the fatigue on the forearm muscles from four subjects,and recorded the sEMG signals of the flexor carpi ulnaris.sEMG's median frequency(MDF) and mean frequency(MF) were extracted by short term Fourier transform(STFT),and the root mean square(RMS) of wavelet coefficients in the frequency band of 5—45 Hz was obtained by continuous wavelet transform(CWT).The results demonstrate that both MDF and MF show downward trends within 1 min; however,RMS shows an upward trend within the same time.The three parameters are closely correlated with absolute values of mean correlation coefficients greater than 0.8.It is suggested that the three parameters above can be used as reliable indicators to evaluate the level of muscle fatigue during isometric contractions. 展开更多
关键词 muscle fatigue isometric contraction time-frequency spectrum analysis median frequency mean frequency root mean square CORRELATION
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Effects of anti-hypertensive drugs on esophageal body contraction 被引量:5
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作者 Koichi Yoshida Kenji Furuta +7 位作者 Kyoichi Adachi Shunji Ohara Terumi Morita Takashi Tanimura Shuji Nakata Masaharu Miki Kenji Koshino Yoshikazu Kinoshita 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第8期987-991,共5页
AIM:To clarify the effects of anti-hypertensive drugs on esophageal contraction and determine their possi-ble relationship with gastro-esophageal reflux disease.METHODS:Thirteen healthy male volunteers were enrolled. ... AIM:To clarify the effects of anti-hypertensive drugs on esophageal contraction and determine their possi-ble relationship with gastro-esophageal reflux disease.METHODS:Thirteen healthy male volunteers were enrolled. Esophageal body peristaltic contractions and lower esophageal sphincter (LES) pressure were measured using high resolution manometry. All subjects were randomly examined on four separate occasions following administrations of nifedipine,losartan,and atenolol,as well as without any drug administration.RESULTS:Peristaltic contractions by the esophageal body were separated into three segments by two troughs. The peak peristaltic pressures in the mid and lower segments of the esophageal body under atenolol administration were signifi cantly higher than those without medication in a supine position. On the other hand,peristaltic pressures under nifedipine administration were lower than those observed without drug ad-ministration. Losartan did not change esophageal body peristalsis. Atenolol elevated LES pressure and slowed peristaltic wave transition,while the effects of nifedip-ine were the opposite. CONCLUSION:Among the anti-hypertensive drugs tested,atenolol enhanced esophageal motor activity,which was in contrast to nifedipine. 展开更多
关键词 Anti-hypertensive drug High-resolution manometry Lower esophageal sphincter Esophageal body contraction Calcium-channel blocker β1 blocker
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Microcrystallization and lattice contraction of NiFe LDHs for enhancing water electrocatalytic oxidation 被引量:6
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作者 Zhicheng Zheng Dan Wu +4 位作者 Gen Chen Ning Zhang Hao Wan Xiaohe Liu Renzhi Ma 《Carbon Energy》 SCIE CAS 2022年第5期901-913,共13页
The lattice-oxygen-mediated mechanism is considered as a reasonable mechanism for the electrochemical catalytic oxygen evolution reaction(OER)of NiFe layered double hydroxides(LDHs).A NiFe LDH with distinct lattice co... The lattice-oxygen-mediated mechanism is considered as a reasonable mechanism for the electrochemical catalytic oxygen evolution reaction(OER)of NiFe layered double hydroxides(LDHs).A NiFe LDH with distinct lattice contraction and microcrystallization was synthesized via a simple one-step method using sodium gluconate.The lattice contraction is attributed to the interaction of carbon in sodium gluconate and iron in NiFe LDH.The NiFe LDH with optimized microcrystallization and lattice contraction shows a low overpotential of 217 mV at a current density of 10 mA cm^(−2) and excellent durability of 20 h at a high current density of 100 mA cm^(−2).The results revealed that a contractive metal–oxygen bond could boost the intrinsic activity of active sites and the microcrystallization promotes an increase in the number of active sites in terms of unit area.The chemical environment of oxygen elemental characterization and resistance at different chronopotentiometry times confirm that the lattice oxygen element is indeed involved in the process of OER,supporting the lattice-oxygen-mediated mechanism of NiFe LDH.Density functional theory calculations reveal that contractive metal–oxygen bonds induced a reduction of the adsorption energy barrier of intermediate products,thus improving the intrinsic catalytic activity.The special characteristics of microcrystallization and lattice contraction of NiFe LDH provide a strategy to improve both the number and the intrinsic activity of active sites in a versatile manner. 展开更多
关键词 lattice contraction lattice-oxygen-mediated mechanism microcrystallization NiFe LDH oxygen evolution reaction
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Effects of ghrelin on interdigestive contractions of the rat gastrointestinal tract 被引量:10
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作者 Hiroshi Taniguchi Hajime Ariga +1 位作者 Kirk Ludwig Toku Takahashi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第41期6299-6302,共4页
Ghrelin causes interdigestive contractions of the stom- ach in rats. However, it remains unknown whether ghrelin causes interdigestive contractions in the small intestine. Four strain gauge transducers were implanted ... Ghrelin causes interdigestive contractions of the stom- ach in rats. However, it remains unknown whether ghrelin causes interdigestive contractions in the small intestine. Four strain gauge transducers were implanted on the antrum, duodenum, proximal and distal jejunum. After an overnight fast, gastrointestinal (GI) contrac- tions were recorded in freely moving conscious rats. Spontaneous phase m-like contractions were observed at every 13-16 min in rat GI tract. The fasted motor patterns were replaced by the fed motor pattern imme- diately after food intake. Two minutes after finishing the spontaneous phase Ill-like contractions in the antrum, acyl ghrelin (0.8, 2.4 and 8.0 μg/kg per min) was con- tinuously infused for 30 min. Three-five minutes after the starting ghrelin infusion, augmented phase Ⅲ-like contractions were observed at the antrum, duodenum, and jejunum. Ghrelin infusion (0.8, 2.4 and 8.0μg/kg per min) significantly increased motility index of phase Ⅲ-like contractions at the antrum and jejunum in a dose dependent manner, compared to that of saline in- jection. Thus, it is likely that exogenously administered ghrelin causes phase Ⅲ-like contraction at the antrum, which migrates to the duodenum and jejunum. The possible role of 5-HT, in addition to ghrelin, in mediating intestinal migrating motor complex (MMC), is discussed. 展开更多
关键词 Phase Ⅲ-like contractions Strain gage transducers Motility index
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