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Something about random normed modules 被引量:1
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作者 Linhu Zhu Cangyi Liu 《Chinese Science Bulletin》 SCIE EI CAS 1998年第7期560-562,共3页
The fourth axiom in the definition of real random normed module is superfluous. A necessary and sufficient condition is given that continuous random linear functionals over complex random normed spaces are a.s. bounde... The fourth axiom in the definition of real random normed module is superfluous. A necessary and sufficient condition is given that continuous random linear functionals over complex random normed spaces are a.s. bounded, and furthermore, in the sense of isometrical isomorphism it is proved the fourth axiom in the complex random normed module is superfluous. 展开更多
关键词 RANDOM NORMED space RANDOM NORMED MODULE isometrical isomorphism.
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METRICS,PROBABILISTIC METRICS AND RANDOM METRICS 被引量:1
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作者 GUO Tiexin(Department of Mathematics,Xiamen University, Fujian Xiamen 361005,China) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1995年第2期182-186,共5页
METRICS,PROBABILISTICMETRICSANDRANDOMMETRICSGUOTiexin(DepartmentofMathematics,XiamenUniversity,FujianXiamen3... METRICS,PROBABILISTICMETRICSANDRANDOMMETRICSGUOTiexin(DepartmentofMathematics,XiamenUniversity,FujianXiamen361005,China)Abstr... 展开更多
关键词 Largest weak T-NORM isometrical isomorphism METRIC space-system PROBABILISTIC METRIC space-system RANDOM METRIC space-system
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Minimal Surfaces and Gauss Curvature of Conoid in Fins-ler Spaces with (<i>α</i>, <i>β</i>)-Metrics
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作者 Dinghe Xie Qun He 《Advances in Pure Mathematics》 2012年第4期220-225,共6页
In this paper, minimal submanifolds in Finsler spaces with (α, β)-metrics are studied. Especially, helicoids are also minimal in (α, β)-Minkowski spaces. Then the minimal surfaces of conoid in Finsler spaces with ... In this paper, minimal submanifolds in Finsler spaces with (α, β)-metrics are studied. Especially, helicoids are also minimal in (α, β)-Minkowski spaces. Then the minimal surfaces of conoid in Finsler spaces with (α, β)-metrics are given. Last, the Gauss curvature of the conoid in the 3-dimension Randers-Minkowski space is studied. 展开更多
关键词 isometrical IMMERSION Minimal SUBMANIFOLD β)-Metric Conoid Surface GAUSS Curvature
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Star-shaped Differentiable Functions and Star-shaped Differentials
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作者 PAN SHAO-RONG ZHANG HONG-WEI ZHANG LI-WEI 《Communications in Mathematical Research》 CSCD 2010年第1期41-52,共12页
Based on the isomorphism between the space of star-shaped sets and the space of continuous positively homogeneous real-valued functions, the star-shaped differential of a directionally differentiable function is defin... Based on the isomorphism between the space of star-shaped sets and the space of continuous positively homogeneous real-valued functions, the star-shaped differential of a directionally differentiable function is defined. Formulas for star-shaped differential of a pointwise maximum and a pointwise minimum of a finite number of directionally differentiable functions, and a composite of two directionaUy differentiable functions are derived. Furthermore, the mean-value theorem for a directionaUy differentiable function is demonstrated. 展开更多
关键词 The space of star-shaped sets gauge function isometrical isomorphism directionally differentiable function star-shaped differential mean-value theorem
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模糊度量空间中的伪度量结构及等距同构 被引量:3
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作者 杨浩 吴健荣 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2021年第6期95-100,共6页
由于模糊度量在彩色图像滤波等方面的成功应用,近年来该领域的研究引起了人们的重视.在将经典度量空间中的重要结论推广到模糊度量空间中的同时,研究方法上的创新显得特别重要.其中,将模糊度量分解为一族经典度量,建立模糊度量的分解定... 由于模糊度量在彩色图像滤波等方面的成功应用,近年来该领域的研究引起了人们的重视.在将经典度量空间中的重要结论推广到模糊度量空间中的同时,研究方法上的创新显得特别重要.其中,将模糊度量分解为一族经典度量,建立模糊度量的分解定理无疑是十分有意义的.已有的分解定理主要是针对取小算子的模糊度量展开的,在应用上具有很大的局限性.本文引入了星伪度量族的概念作为对伪度量族概念的推广,利用这一概念,建立了针对取一般连续t-模的模糊度量的分解定理.同时,本文给出了模糊度量空间与伪度量族空间等距同构的充分条件和必要条件,由此建构起模糊度量与伪度量族之间的联系,为一般意义下的模糊度量的研究提供了一种新的有效途径. 展开更多
关键词 模糊集 模糊度量 伪度量 分解 等距同构
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波动方程的解与再生核空间的关系 被引量:2
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作者 邢佳 邓彩霞 倪金霞 《数学的实践与认识》 CSCD 北大核心 2008年第6期203-206,共4页
从线性变换入手,应用再生核空间理论,建立了波动方程的解与再生核空间的关系.得到了波动方程的解的反演公式及等距等式,为再生核理论的应用提供了新的思路.
关键词 再生核 等距等式 反演公式
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内侧髌股韧带重建术中骨骺闭合与否对股骨侧定位方法选择的影响
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作者 贾熠辰 徐斌 郭瑞鹏 《实用骨科杂志》 2023年第4期315-319,共5页
目的 探讨在内侧髌股韧带重建手术过程中骨骺闭合与否对股骨侧定位方法选择的影响。方法 选取2018年9月至2022年5月安徽医科大学第一附属医院运动创伤与关节镜外科收治的复发性髌骨脱位患者共88例,骨骺未闭合组48例,其中男性20例,女性28... 目的 探讨在内侧髌股韧带重建手术过程中骨骺闭合与否对股骨侧定位方法选择的影响。方法 选取2018年9月至2022年5月安徽医科大学第一附属医院运动创伤与关节镜外科收治的复发性髌骨脱位患者共88例,骨骺未闭合组48例,其中男性20例,女性28例;年龄12~15岁,平均(12.72±1.62)岁。骨骺闭合患者40例,男性14例,女性26例;年龄16~24岁,平均(19.25±1.58)岁。行患侧膝关节三维CT及X线检查,并分别于三维CT影像上标记出Schottle点为S点;内收肌结节与股骨内侧髁中点为A点;Fujino定位点为F点。分别测量SA、SF之间的距离。随机采用内收肌结节辅助定位法及中心定位法两种定位方法进行术中定位,最后通过比较青少年患者末次随访的Kujala评分、Lysholm评分等方法评价上述两种定位法在治疗青少年髌骨脱位中的临床疗效。结果 相较于骨骺闭合的患者,临床上常用的解剖学定位方法:中点定位法,确定的股骨侧定位点(A点)与S点之间距离差异有统计学意义(P<0.05),而以内收肌结节辅助定位法为代表的解剖学定位法,其运用于骨骺未闭合患者中的“等长性”效果更佳,同时其术后随访的临床疗效显著优于前者。结论 相较于成人MPFL重建手术中股骨侧的定位方法,中点定位法在骨骺未闭合的患者中并非最优选择,而内收肌结节辅助定位法更加适用于儿童或骨骺未闭合的青少年。 展开更多
关键词 股骨远端骨骺 青少年 髌骨脱位 内侧髌股韧带重建 股骨等距点
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CAXA的等距缩放在模具设计和制造中的应用
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作者 吕小莲 程新平 吕小荣 《组合机床与自动化加工技术》 北大核心 2004年第9期78-78,80,共2页
介绍了对任意平面二维图形进行放大、缩小的程序—OFFSET程序的实现方法 。
关键词 模具 CAXA 等距缩放 压力中心
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关于概率准度量族空间的等距同构(英文)
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作者 刘明学 郭铁信 《数学研究》 CSCD 1998年第4期381-387,共7页
引入了带指标的准度量族空间的概念,讨论了带指标的准度族空间与概率准度量族空间和随机准度量族空间之间的关系,建立了这些空间的一些性质,研究了这些空间的等矩同构.
关键词 等距同构 概率 空间 随机 度量 性质 指标 标的 概念
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膝关节屈肌和伸肌等速向心、等速离心及等长测试的研究 被引量:72
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作者 吴毅 杨晓冰 +2 位作者 李云霞 范振华 胡永善 《中国运动医学杂志》 CAS CSCD 北大核心 1996年第3期193-196,199,共5页
本文通过运用Cybex-6000型等速测力系统对25名健康男青年膝屈肌和伸肌进行等速向心、等速离心及等长测试,来比较膝肌肉向心收缩、离心收缩和等长收缩的功能,并探讨其相互间的关系。结果表明:等速测试时,膝屈肌和伸肌离... 本文通过运用Cybex-6000型等速测力系统对25名健康男青年膝屈肌和伸肌进行等速向心、等速离心及等长测试,来比较膝肌肉向心收缩、离心收缩和等长收缩的功能,并探讨其相互间的关系。结果表明:等速测试时,膝屈肌和伸肌离心收缩的肌力明显大于向心收缩。在膝屈曲60°时,离心收缩和等长收缩的肌力同样明显大于向心收缩,但离心收缩与等长收缩相比无显著性差异。随运动速度增加,屈肌和伸肌向心收缩的肌力明显下降,而离心收缩的肌力无明显变化。 展开更多
关键词 向心收缩 离心收缩 等长收缩 肌肉收缩 膝关节
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Patterns of above-and belowground biomass allocation in China's grasslands:Evidence from individual-level observations 被引量:56
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作者 WANG Liang NIU KeChang +1 位作者 YANG YuanHe ZHOU Peng 《Science China(Life Sciences)》 SCIE CAS 2010年第7期851-857,共7页
Above-and belowground biomass allocation not only influences growth of individual plants,but also influences vegetation structures and functions,and consequently impacts soil carbon input as well as terrestrial ecosys... Above-and belowground biomass allocation not only influences growth of individual plants,but also influences vegetation structures and functions,and consequently impacts soil carbon input as well as terrestrial ecosystem carbon cycling.However,due to sampling difficulties,a considerable amount of uncertainty remains about the root:shoot ratio(R/S),a key parameter for models of terrestrial ecosystem carbon cycling.We investigated biomass allocation patterns across a broad spatial scale.We collected data on individual plant biomass and systematically sampled along a transect across the temperate grasslands in Inner Mongolia as well as in the alpine grasslands on the Tibetan Plateau.Our results indicated that the median of R/S for herbaceous species was 0.78 in China's grasslands as a whole.R/S was significantly higher in temperate grasslands than in alpine grasslands(0.84 vs.0.65).The slope of the allometric relationship between above-and belowground biomass was steeper for temperate grasslands than for alpine.Our results did not support the hypothesis that aboveground biomass scales isometrically with belowground biomass.The R/S in China's grasslands was not significantly correlated with mean annual temperature(MAT) or mean annual precipitation(MAP).Moreover,comparisons of our results with previous findings indicated a large difference between R/S data from individual plants and communities.This might be mainly caused by the underestimation of R/S at the individual level as a result of an inevitable loss of fine roots and the overestimation of R/S in community-level surveys due to grazing and difficulties in identifying dead roots.Our findings suggest that root biomass in grasslands tended to have been overestimated in previous reports of R/S. 展开更多
关键词 aboveground biomass ALLOMETRY alpine grassland belowground biomass Inner Mongolia isometric relationship root:shoot ratio temperate grassland Tibetan Plateau
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The 1-Lipschitz mapping between the unit spheres of two Hilbert spaces can be extended to a real linear isometry of the whole space 被引量:48
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作者 定光桂 《Science China Mathematics》 SCIE 2002年第4期479-483,共5页
Let E and F be Hilbert spaces with unit spheres S1(E) and S1(F). Suppose that V0 S1(E)→S1(F) is a Lipschitz mapping with Lipschitz constant k=1 such that -V0[S1(E)] V0[S1(E)]. Then V0 can be extended to a real linear... Let E and F be Hilbert spaces with unit spheres S1(E) and S1(F). Suppose that V0 S1(E)→S1(F) is a Lipschitz mapping with Lipschitz constant k=1 such that -V0[S1(E)] V0[S1(E)]. Then V0 can be extended to a real linear isometric mapping V from E into F. In particular, every isometric mapping from S1(E) onto S1(F) can be extended to a real linear isometric mapping from E onto F. 展开更多
关键词 isometrIC mapping STRICTLY convex SMOOTH point.
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前交叉韧带重建术中隧道定位对移植物等距特性影响的研究 被引量:34
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作者 Aljaberi Mohammed 曾炳芳 +1 位作者 赵金忠 张经伟 《中华创伤骨科杂志》 CAS CSCD 2006年第7期663-667,共5页
目的探讨前交义韧带(ACL)重建术中股骨和胫骨隧道定位变化对移植物等距特性的影响。方法选用10具正常新鲜冷冻尸体膝关节标本,在股骨取3个定位点,第一个定位点位于右膝11点(左膝1点)过顶点前方5~6 mm处,作为前束点;第二点位于前束点前... 目的探讨前交义韧带(ACL)重建术中股骨和胫骨隧道定位变化对移植物等距特性的影响。方法选用10具正常新鲜冷冻尸体膝关节标本,在股骨取3个定位点,第一个定位点位于右膝11点(左膝1点)过顶点前方5~6 mm处,作为前束点;第二点位于前束点前5 mm处,作为误差点;第三点位于屈膝90°时,ACL附着区长轴与经股骨-胫骨接触点的垂直线的交点,作为后束点。在ACL胫骨附着区的前后径上取3个定位点,一个位于原ACL附着区中心,称为中心点;一个位于中心点后5 mm处,称为5 mm后点;一个位于中心点后10 mm处,称为10 mm后点。模拟ACL重建步骤,经各个股骨和胫骨定位点分别钻直径为2 mm的骨隧道,通过测量钢丝和等距测量仪来检测膝关节屈曲过程中各个股骨隧道内口相对于各个胫骨隧道内口的距离变化。结果相对于某一个固定的股骨隧道内口,胫骨隧道内口的前后移位变化对移植物等距特性的影响差异无显著性意义(P>0.05);相对于某一个固定的胫骨隧道内口,股骨隧道内口位置的变化对移植物等距特性的影响差异有极显著性意义(P<0.01)。从膝关节完全伸直到极度屈曲的过程中,如果股骨隧道内口选择在前束点,则两内口间移植物长度变化在生理等距范围内;若选择在误差点,则两内口间移植物长度变化表现为超出生理等距范围的延长;若选择在后束点,则两内口间移植物长度变化表现为超出生理等距范围的短缩。结论ACL重建时,胫骨隧道内口在ACL附着区中心与棘间区后缘之间的前后移位对移植物等距特性无明显影响,股骨隧道内口的移位对移植物的等距特性有明显影响。 展开更多
关键词 前交叉韧带 骨隧道 重建 等距性
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中国青年踝关节跖屈、背屈肌群力量的研究 被引量:33
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作者 王向东 刘学贞 +2 位作者 仰红慧 胡水清 卢德明 《中国运动医学杂志》 CAS CSCD 北大核心 2003年第6期569-572,共4页
目的 :(1 )通过测试健康青年踝关节背屈、跖屈肌群的力量 ,为运动训练、损伤和康复提供实验依据 ;(2 )探讨健康青年踝关节跖屈、背屈肌群工作的生物力学规律。方法 :利用CYBEX -60 0 0型测力系统对 70例健康青年 (男 35人 ,女 35人)踝... 目的 :(1 )通过测试健康青年踝关节背屈、跖屈肌群的力量 ,为运动训练、损伤和康复提供实验依据 ;(2 )探讨健康青年踝关节跖屈、背屈肌群工作的生物力学规律。方法 :利用CYBEX -60 0 0型测力系统对 70例健康青年 (男 35人 ,女 35人)踝关节背屈、跖屈肌群进行等长和等速测试。结果发现 :在等长测试中 ,男、女踝关节背屈肌群峰力矩均随测试角度的增加而增加 ,跖屈峰力矩随测试角的增加而减小。在等速向心测试中 ,男、女踝关节背屈、跖屈肌群峰力矩随测试角速度的增加而减小。两种测试均表明 ,跖屈肌群峰力矩大于背屈肌群峰力矩 (P <0 0 5)。男性与女性相比 ,绝对力矩较大(P <0 0 5) ;但去除体重因素后 ,男、女相对力矩间差距缩小。结果表明 ,用相对峰力矩比较男、女肌力的差别更为合理。通过对踝关节背屈 /跖屈肌群峰力矩比值的研究 ,发现我国健康青年普遍踝关节背屈肌群力量比较薄弱 。 展开更多
关键词 中国青年 踝关节跖屈 背屈肌群 力量 运动训练 损伤 康复 等速向心测试 等长测试 峰力矩
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The Representation Theorem of onto Isometric Mappings between Two Unit Spheres of l^1(Г) Type Spaces and The Application to the Isometric Extension Problem 被引量:30
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作者 Guang Gui DING 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2004年第6期1089-1094,共6页
In this paper,we first derive the representation theorem of onto isometric mappings in theunit spheres of l~1(F) type spaces,and then conclude that such mappings can be extended to the wholespace as real linear isomet... In this paper,we first derive the representation theorem of onto isometric mappings in theunit spheres of l~1(F) type spaces,and then conclude that such mappings can be extended to the wholespace as real linear isometrics by using a previous result of the author. 展开更多
关键词 isometric mapping isometric extension
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The representation theorem of onto isometric mappings between two unit spheres of l∞-type spaces and the application on isometric extension problem 被引量:30
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作者 DING Guanggui 《Science China Mathematics》 SCIE 2004年第5期722-729,共8页
In this paper, we first derive the representation theorem of onto isometric mappings in the unit spheres of real l∞-type spaces, then we conclude that such mappings can be extended to the whole space as (real) linear... In this paper, we first derive the representation theorem of onto isometric mappings in the unit spheres of real l∞-type spaces, then we conclude that such mappings can be extended to the whole space as (real) linear isometries. 展开更多
关键词 isometrIC mapping isometrIC extension.
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The isometric extension problem in the unit spheres of l^p(Г)(p >1) type spaces 被引量:24
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作者 定光桂 《Science China Mathematics》 SCIE 2003年第3期333-338,共6页
In this paper, we first derive the representation theorem of onto isometric mappings in the unit spheres of l p (Г) (@#@(p >) 1,p ≠ 2 type spaces, and then we conclude that such mappings can be extended to the wh... In this paper, we first derive the representation theorem of onto isometric mappings in the unit spheres of l p (Г) (@#@(p >) 1,p ≠ 2 type spaces, and then we conclude that such mappings can be extended to the whole space as real linear isometries by using the previous result of the author. 展开更多
关键词 isometric mapping strictly convex
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Extension of Isometries Between the Unit Spheres of Normed Space E and C(Ω) 被引量:18
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作者 Xi Nian FANG Jian Hua WANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第6期1819-1824,共6页
In this paper, we study the extension of isometries between the unit spheres of normed space E and C(Ω). We obtain that any surjective isometry between the unit spheres of normed space E and C(Ω) can be extended... In this paper, we study the extension of isometries between the unit spheres of normed space E and C(Ω). We obtain that any surjective isometry between the unit spheres of normed space E and C(Ω) can be extended to be a linear isometry on the whole space E and give an affirmative answer to the corresponding Tingley's problem (where Ω be a compact metric space). 展开更多
关键词 isometric mapping isometric extension Tingley's problem
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不同运动疗法对膝骨性关节炎的治疗作用 被引量:21
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作者 吴玉玲 吴敏魁 +2 位作者 沈良册 叶宏 林建强 《颈腰痛杂志》 2013年第4期335-338,共4页
目的探讨不同运动疗法对膝骨性关节炎的治疗效果。方法 100例膝骨性关节炎患者随机分为治疗组(n=50例)和对照组(n=50例),两组均采用超短波电疗、关节活动度训练、有氧运动、ADL指导;治疗组在此基础上加等速训练,对照组在此基础上加徒手... 目的探讨不同运动疗法对膝骨性关节炎的治疗效果。方法 100例膝骨性关节炎患者随机分为治疗组(n=50例)和对照组(n=50例),两组均采用超短波电疗、关节活动度训练、有氧运动、ADL指导;治疗组在此基础上加等速训练,对照组在此基础上加徒手等长、等张肌力训练。结果两组患者治疗4周后,视觉模拟评分、Lysholm膝关节评分、膝关节伸直位最大负荷量均比治疗前明显改善(P<0.01);治疗组的疗效明显优于对照组(P<0.01和P<0.05)。结论等速训练在膝关节骨性关节炎的康复中有明显的治疗作用。 展开更多
关键词 超短波 等速训练 等长 等张训练 膝骨性关节炎
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Opiate-induced constipation related to activation of small intestine opioid μ2-receptors 被引量:20
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作者 Wency Chen Hsien-Hui Chung Juei-Tang Cheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第12期1391-1396,共6页
AIM: To investigate the role of opioid p-receptor subtype in opiate-induced constipation (OIC).METHODS: The effect of Ioperamide on intestinal transit was investigated in mice. Ileum strips were isolated from 12-w... AIM: To investigate the role of opioid p-receptor subtype in opiate-induced constipation (OIC).METHODS: The effect of Ioperamide on intestinal transit was investigated in mice. Ileum strips were isolated from 12-wk-old male BALB/c mice for identification of isometric tension. The ileum strips were precontracted with 1 μmol/L acetylcholine (ACh). Then, decrease in muscle tone (relaxation) was characterized after cumu- lative administration of 0.1-10μ~mol/L Ioperamide into the organ bath, for a concentration-dependent study. Specific blockers or antagonists were used for pretreat- ment to compare the changes in Ioperamide-induced relaxation.RESULTS: In addition to the delay in intestinal transit, Ioperamide produced a marked relaxation in isolated ileum precontracted with ACh, in a dose-dependent manner. This relaxation was abolished by cyprodime,a selective opioid p-receptor antagonist, but not modified by naloxonazine at a dose sufficient to block opioid μ-1 receptors. Also, treatment with opioid μ-1 receptor agonist failed to modify the muscle tone. Moreover, the relaxation by Ioperamide was attenuated by glibenclamide at a dose sufficient to block ATP-sensitive K^+ (KATP) channels, and by protein kinase A (PKA) inhibitor, but was enhanced by an inhibitor of phosphodiesterase for cyclic adenosine monophosphate (cAMP).CONCLUSION: Loperamide induces intestinal relaxa- tion by activation of opioid μ-2 receptors via the cAMP- PKA pathway to open KATp channels, relates to OIC. 展开更多
关键词 ATP-sensitive K^+ channels isometric tension LOPERAMIDE Opioid p-receptors Small intestine
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