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Common Fixed Points for Two Mappings with Implicit-linear Contractions on Partially Ordered 2-metric Spaces
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作者 PIAO YONG-JIE 《Communications in Mathematical Research》 CSCD 2019年第3期225-234,共10页
In this paper, we introduce a new class U of 3-dimensional real functions, use U and a 2-dimensional real function ? to construct a new implicit-linear contractive condition and obtain some existence theorems of commo... In this paper, we introduce a new class U of 3-dimensional real functions, use U and a 2-dimensional real function ? to construct a new implicit-linear contractive condition and obtain some existence theorems of common fixed points for two mappings on partially ordered 2-metric spaces and give a sufficient condition under which there exists a unique common fixed point. The obtained results goodly generalize and improve the corresponding conclusions in references. 展开更多
关键词 2-metric space class U of functions implicit-linear contraction common fixed point
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Numerical simulation of size contraction of Typhoon Cempaka(2021)
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作者 Lingfeng Sun Qingqing Li 《Atmospheric and Oceanic Science Letters》 2025年第2期29-35,共7页
In 2021,Cempaka,a tiny tropical cyclone,made landfall in China.As the TC intensified prior to landfall,the tropical cyclone size measured with precipitation decreased significantly.A numerical simulation was conducted... In 2021,Cempaka,a tiny tropical cyclone,made landfall in China.As the TC intensified prior to landfall,the tropical cyclone size measured with precipitation decreased significantly.A numerical simulation was conducted to examine the possible processes modulating the storm size.Azimuthally mean potential vorticity(PV)was found to decrease mainly in the middle to upper troposphere between 50-and 80-km radii.The PV budget results indicate that the advection and generation of mean PV associated with asymmetric processes,rather than the symmetric processes,primarily contributed to the decrease in mean PV.These asymmetric processes leading to a negative PV tendency were likely associated with inactive outer rainbands.In contrast,the tangential winds simultaneously expanded radially outward,possibly related to inner-core diabatic heating.The findings here emphasize the importance of outer rainband activity in tropical cyclone size change. 展开更多
关键词 Typhoon cempaka Vortex size contraction Potential vorticity budget Asymmetric structure Outer rainband
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Controlled proximal contractions with an application to a class of integral equations
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作者 Mudasir Younis Haroon Ahmad 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期645-665,共21页
In this study,we explore some of the best proximity point results for generalized proximal contractions in the setting of double-controlled metric-type spaces.A non-trivial example is given to elucidate our analysis,a... In this study,we explore some of the best proximity point results for generalized proximal contractions in the setting of double-controlled metric-type spaces.A non-trivial example is given to elucidate our analysis,and some novel results are derived.The discovered results generalize previously known results in the context of a double controlled metric type space environment.This article’s proximity point results are the first of their kind in the realm of controlled metric spaces.To build on the results achieved in this article,we present an application demonstrating the usability of the given results. 展开更多
关键词 integral equation double controlled metric type space proximal contractive mappings coincidence best proximity point
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Efficacy of combining posterior scleral contraction and intravitreal C_(3)F_(8)injection in high myopia with macular hole retinal detachment
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作者 Si Chen Jie Ye +6 位作者 Qin-Tuo Pan Fang Huang Lin-Yan Zheng Hui-Fang Ye Yan-Feng Su Yan Li Shuang-Qian Zhu 《International Journal of Ophthalmology(English edition)》 2025年第6期1077-1084,共8页
AIM:To evaluate the efficacy and safety of combining posterior scleral contraction(PSC)with intravitreal perfluoropropane(C_(3)F_(8))injection in high myopia with macular hole retinal detachment(MHRD).METHODS:A total ... AIM:To evaluate the efficacy and safety of combining posterior scleral contraction(PSC)with intravitreal perfluoropropane(C_(3)F_(8))injection in high myopia with macular hole retinal detachment(MHRD).METHODS:A total of 22 participants(22 eyes)with high myopia[axial length(AL)≥26.5 mm]and MHRD who underwent PSC combined with intravitreal C_(3)F_(8)injection,with at least 6mo of follow-up were retrospectively recruited.Outcome measures included best-corrected visual acuity(BCVA),AL,optical coherence tomography(OCT)findings,and adverse events.Retinal recovery was categorized as type Ⅰ(macular hole bridging with retinal reattachment)or type Ⅱ(reattachment without hole bridging).RESULTS:The mean age of participants was 62.1±8.8y and mean follow-up duration was 9.18±4.21mo.Complete retinal reattachment was observed in 11 eyes(50%)at postoperative day 1,19 eyes(86.3%)at week 1,and all 22 eyes at month 1.Ten eyes(45.5%)achieved type Ⅰ recovery and 12 eyes(54.5%)achieved type Ⅱ.Mean BCVA improved from 1.68±0.84 logMAR before surgery to 1.21±0.65 logMAR after surgery(P<0.001),and AL was significantly reduced compared to baseline(29.07±2.05 vs 30.8±2.2 mm;P<0.001).No serious complications were reported.CONCLUSION:PSC combined with intravitreal C_(3)F_(8)injection is a safe and effective treatment for MHRD in highly myopic eyes,especially for retinal detachment limited within the vascular arcade. 展开更多
关键词 posterior scleral contraction retinal detachment macular hole MYOPIA C_(3)F_(8)
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Suzuki-Type(μ,v)-Weak Contraction for the Hesitant Fuzzy Soft Set Valued Mappings with Applications in Decision Making
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作者 Muhammad Sarwar Rafiq Alam +2 位作者 Kamaleldin Abodayeh Saowaluck Chasreechai Thanin Sitthiwirattham 《Computer Modeling in Engineering & Sciences》 2025年第5期2213-2236,共24页
In this manuscript,the notion of a hesitant fuzzy soft fixed point is introduced.Using this notion and the concept of Suzuki-type(μ,ν)-weak contraction for hesitant fuzzy soft set valued-mapping,some fixed point res... In this manuscript,the notion of a hesitant fuzzy soft fixed point is introduced.Using this notion and the concept of Suzuki-type(μ,ν)-weak contraction for hesitant fuzzy soft set valued-mapping,some fixed point results are established in the framework of metric spaces.Based on the presented work,some examples reflecting decision-making problems related to real life are also solved.The suggested method’s flexibility and efficacy compared to conventional techniques are demonstrated in decision-making situations involving uncertainty,such as choosing the best options in multi-criteria settings.We noted that the presented work combines and generalizes two major concepts,the idea of soft sets and hesitant fuzzy set-valued mapping from the existing literature. 展开更多
关键词 Hesitant fuzzy soft set valued mapping Suzuki-type(μ ν)-weak contraction fixed point decision making problem
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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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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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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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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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Ge-Gen Decoction attenuates oxytocin-induced uterine contraction and writhing response: potential application in primary dysmenorrhea therapy 被引量:19
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作者 YANG Lu CHAI Cheng-Zhi +4 位作者 YUE Xin-Yi YAN Yan KOU Jun-Ping CAO Zheng-Yu YU Bo-Yang 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第2期124-132,共9页
The uterine tetanic contraction and uterine artery blood flow reduction are possible reasons for primary dysmenorrhea(PD). In the present study, we aimed to evaluate the uterine relaxant effect and the influence on ut... The uterine tetanic contraction and uterine artery blood flow reduction are possible reasons for primary dysmenorrhea(PD). In the present study, we aimed to evaluate the uterine relaxant effect and the influence on uterine artery blood velocity of Ge-Gen Decoction(GGD), a well-known Chinese herbal formula. In female ICR mice, uterine contraction was induced by oxytocin exposure following estradiol benzoate pretreatment, and the uterine artery blood velocity was detected by Doppler ultrasound. Histopathological examination of the uterine tissue samples were performed by H&E staining. Ex vivo studies demonstrated that oxytocin, posterior pituitary, or acetylcholine induced contractions in isolated mouse uterus. GGD inhibited both spontaneous and stimulated contractions. In vivo study demonstrated that GGD significantly reduced oxytocin-induced writhing responses with a maximal inhibition of 87%. Further study demonstrated that GGD normalized oxytocin-induced abnormalities of prostaglandins F_2 alpha(PGF_(2α)) and Ca^(2+) in mice. In addition, injection of oxytocin induced a decrease in uterine artery blood flow velocity. Pretreatment with GGD reversed the oxytocin response on blood flow velocity. Histopathological examination showed pretreatment with GGD alleviated inflammation and edema in the uterus when compared with the model group. Both ex vivo and in vivo results indicated that GGD possessed a significant spasmolytic effect on uterine tetanic contraction as well as improvement on uterine artery blood velocity which may involve PGF_(2α) and Ca^(2+) signaling, suggesting that GGD may have a clinic potential in PD therapy. 展开更多
关键词 Primary dysmenorrheal Spasmolytic and analgesic effect Uterine contraction Uterine artery blood flow Ge-Gen Decoction
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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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Effect of burden and origin sites of premature ventricular contractions on left ventricular function by 7-day Holter monitor 被引量:4
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作者 Wenhua Xu Mingfang Li +12 位作者 Minglong Chen Bing Yang Daowu Wang Xiangqing Kong Hongwu Chen Weizhu Ju Kai Gu Kejiang Cao Hailei Liu Qi Jiang Jiaojiao Shi Yan Cui Hong Wang 《The Journal of Biomedical Research》 CAS CSCD 2015年第6期465-474,共10页
Recent studies have shown that premature ventricular contractions (PVCs) could enlarge the heart, but its risk factors are incompletely understood as a single 24-hour recording cannot reflect the true PVC burden due... Recent studies have shown that premature ventricular contractions (PVCs) could enlarge the heart, but its risk factors are incompletely understood as a single 24-hour recording cannot reflect the true PVC burden due to day-to-day variability. Our purpose was to investigate the effect of burden and origin sites on left ventricular (LV) function in patients with PVCs by 7-day Holter electrocardiography (ECG). From May 2012 to August 2013, 112 consecutive patients with PVCs were recruited from the authors' affiliated hospital. All patients received 2-dimensional transthoracic echocardiography, 12-lead routing ECG and 7-days Holter ECG. Serum N-terminal pro- brain natriuretic peptide (NT-proBNP) levels were measured. A total of 102 participants with PVCs were included in the final analysis. Origin of PVCs from the tricuspid annulus had the highest burden and NT-proBNP level. LV papillary muscle had a higher LV ejection fraction (EF) level and a lower LV end-systolic dimension (ESD) than other PVC foci (P〈0.05). The high burden group had a higher LV end-diastolic dimension (EDD) and LVESD but lower LVEF than the other two groups (P〈0.05). Female, older age, physical work, and history of PVCs had a significantly positive correlation with symptoms. Male, older age, physical work, and high burden were positive predictors of enlarged LVEDD, LVESD and higher serum NT-proBNP level, but lower LVEF. Seven-day dynamic ECG Holter monitor showed the true PVC burden on patients with PVCs. PVCs with a lower burden or origin from the LV papillary muscle and the fascicle were relatively benign, while PVCs with a higher burden or origin from the tricuspid annulus may lead to cardiac dysfunction. 展开更多
关键词 premature ventricular contractions BURDEN origin sites left ventricular function
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Biomechanical response of skeletal muscle to eccentric contractions 被引量:3
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作者 Richard L.Lieber 《Journal of Sport and Health Science》 SCIE 2018年第3期294-309,共16页
The forced lengthening of an activated skeletal muscle has been termed an eccentric contraction(EC).This review highlights the mechanically unique nature of the EC and focuses on the specific disruption of proteins wi... The forced lengthening of an activated skeletal muscle has been termed an eccentric contraction(EC).This review highlights the mechanically unique nature of the EC and focuses on the specific disruption of proteins within the cell known as cytoskeletal proteins.The major intermediate filament cytoskeletal protein,desmin,has been the focus of work in this area because changes to desmin occur within minutes of ECs and because desmin has been shown to play both a mechanical and biologic role in a muscle's response to EC.It is hoped that these types of studies will assist in decreasing the incidence of muscle injury in athletes and facilitating the development of new therapies to treat muscle injuries. 展开更多
关键词 CYTOSKELETON ECCENTRIC contraction Inflammation MUSCLE INJURY MUSCLE mechanics
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Effects of anti-hypertensive drugs on esophageal body contraction 被引量:6
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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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Developmental changes in contraction of gastric smooth muscle cells in rats correlate with their differences in RhoA/ROCK pathway 被引量:2
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作者 Othman Al-Shboul Mahmoud Alfaqih +6 位作者 Ayman Mustafa Ahmed Al-Dwairi Mohammad Alqudah Saja Haifawi Mohanad Alebbini Mohammad Al-Zaareer Khobaib Alahmar 《The Journal of Biomedical Research》 CAS CSCD 2019年第5期289-296,共8页
Previous research has shown that smooth muscle of the stomach undergoes developmental changes in the intracellular regulatory mechanism responsible for the contractile process. Whether these developmental changes rela... Previous research has shown that smooth muscle of the stomach undergoes developmental changes in the intracellular regulatory mechanism responsible for the contractile process. Whether these developmental changes relate to differences in the expression and/or activity of the key enzymes regulating smooth muscle contraction has not been previously evaluated. Therefore, we aimed to examine the expression and activation of the small monomeric G protein "Rho A" and Rho kinase(ROCK) as well as their correlation with the contraction of gastric smooth muscle cells(GSMCs) in newborn vs. adult rats. Freshly isolated single GSMCs from Sprague-Dawley rats at 1 week(newborn) and 3 months(adult) of age were used in the study. Protein and m RNA expression levels of both ROCK2 and total Rho A were higher in adult compared to newborn rats. Moreover, acetylcholine(ACh)-induced contractions of GSMCs in adult rats were significantly higher than that in newborn animals. Meanwhile,ROCK and Rho activation was higher in adult stomach cells compared to newborn ones. Pretreatment of GSMCs with Y-27632, the ROCK inhibitor, significantly reduced ACh-induced contraction in both groups of cells and greatly abolished contractile differences. In conclusion, our results indicate that Rho A/ROCK pathway and contraction of stomach muscle cells are under developmental regulation. 展开更多
关键词 STOMACH smooth muscle contraction RHO KINASE
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Role of intracellular calcium in contraction of internal anal sphincter 被引量:2
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作者 NIU Wei Xin 1, QIN Xin Yu 1, LU Ying Qing 2, SHI Nian Ci 2 and WANG Cheng Pei 1 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第2期95-96,共2页
INTRODUCTIONInternalanalsphincter(IAS)isacontinuationofthesmoothcircularmusclelayerthickenedattherectum,inne... INTRODUCTIONInternalanalsphincter(IAS)isacontinuationofthesmoothcircularmusclelayerthickenedattherectum,innervatedbyvegetativ... 展开更多
关键词 INTRACELLULAR CALCIUM INTERNAL ANAL SPHINCTER ryanodine muscle contraction
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Experimental Study of Assessment on Ventricular Activation Origin and Contraction Sequence by Doppler Tissue Imaging 被引量:4
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作者 冀瑞平 王新房 +3 位作者 郑宗锷 刘望彭 李治安 刘俐 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第1期52-57,共6页
To evaluate the possibility and accuracy of Doppler tissue image (DTI) on assessment of normal and abnormal ventricular activation and contraction sequence, 9 open chest canine hearts were analyzed by acceleration mod... To evaluate the possibility and accuracy of Doppler tissue image (DTI) on assessment of normal and abnormal ventricular activation and contraction sequence, 9 open chest canine hearts were analyzed by acceleration mode, M mode, and spectrum mode DTI. Our results showed that: (1) Acceleration mode DTI could show the origin of activation and conduction sequence on line; (2) M mode DTI revealed that the activation in mid interventricular septum was earlier than that in mid left ventricular posterior wall at sinus activation; (3) Spectrum DTI showed the ventricular endocardium was activated earlier than the ventricular epicardium in all segments at sinus rhythm. The earliest site of activation of the normal ventricular wall was at middle interventricular septum; the latest site was at basal posterior wall; the contraction sequence was different at the different walls; (4) During abnormal ventricular activation, mid left ventricular posterior wall was activated earliest in accordance with the pacing sites. Abnormal ventricular activation was slower than sinus activation, and the contraction sequence varied at different sites of ventricular wall. It is concluded that DTI can be used to localize the origin of normal or abnormal myocardial activation and to assess the contraction sequence conveniently, accurately and non invasively. 展开更多
关键词 Doppler tissue imaging sinus activation abnormal ventricular activation contraction sequence
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Effects of adenosine triphosphate concentration on motor force regulation during skeletal muscle contraction 被引量:2
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作者 J. Wei C. Dong B. Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第2期243-249,共7页
We employ a mechanical model of sarcomere to quantitatively investigate how adenosine triphosphate (ATP) concentration affects motor force regulation during skeletal muscle contraction. Our simulation indicates that t... We employ a mechanical model of sarcomere to quantitatively investigate how adenosine triphosphate (ATP) concentration affects motor force regulation during skeletal muscle contraction. Our simulation indicates that there can be negative cross-bridges resisting contraction within the sarcomere and higher ATP concentration would decrease the resistance force from negative cross-bridges by promoting their timely detachment. It is revealed that the motor force is well regulated only when ATP concentration is above a certain level. These predictions may provide insights into the role of ATP in regulating coordination among multiple motors. 展开更多
关键词 Motor force regulation ATP Muscle contraction MYOSIN
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Effects of Amrinone on Cardiac Contraction and Relaxation in Isolated,Perfused Rat Heart 被引量:3
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作者 马业新 赵华月 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1994年第3期165-168,共4页
The effects of amrinone on cardiac contraction and relaxation were assessed in isolated, perfused rat hearts. It was found that the left ventricular developed pressure (LVDP), dp/dtmax and -da/dtmax did not significan... The effects of amrinone on cardiac contraction and relaxation were assessed in isolated, perfused rat hearts. It was found that the left ventricular developed pressure (LVDP), dp/dtmax and -da/dtmax did not significantly increase . and the time constant (τ) did not markedly shorten with perfusion of low concentration ( 1 nmol/L , 100 nmol/L) of amrinone. The perfusion with higher concentration (1000 nmol/L) of amrinone reduced LVDP (P<0. 01 ) ,dp/dtmax (P<0.01) , -dp/dtmax (P<0. 01). and prolonged τ(P< 0. 05) significaiatly. It was assumed that amrinone has no direct positive inotropic effect. and can not improve cardiac relaxation. On the contrary, the cardiac contraction and relax ation will be inhibited at higher concentration of amrinone. 展开更多
关键词 an amrinone cardiac contraction cardiac relaxation
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