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MULTIPLE POSITIVE SOLUTIONS OF SINGULAR THIRD-ORDER PERIODIC BOUNDARY VALUE PROBLEM 被引量:21
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作者 孙经先 刘衍胜 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期81-88,共8页
This paper deals with the singular nonlinear third-order periodic boundary value problem u'' + p(3)u = f (t, u), 0 less than or equal to t less than or equal to 2pi, with u((i)) (0) = u((i)) (2pi), i = 0, 1, 2... This paper deals with the singular nonlinear third-order periodic boundary value problem u'' + p(3)u = f (t, u), 0 less than or equal to t less than or equal to 2pi, with u((i)) (0) = u((i)) (2pi), i = 0, 1, 2, where p is an element of (Graphics) and f is singular at t = 0, t = 1 and u = 0. Under suitable weaker conditions than those of [1], it is proved by constructing a special cone in C[0, 2pi] and employing the fixed point index theory that the problem has at least one or at least two positive solutions. 展开更多
关键词 singular boundary value problem third-order differential system positive solution
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EXISTENCE AND UNIQUENESS FOR THIRD ORDER NONLINEAR BOUNDARY VALUE PROBLEMS 被引量:5
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作者 WANG GUOCAN Department of Basic Science, Dalian Institute of Railway Technology, Dalian 116022 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第1期7-16,共10页
In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower soluti... In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower solutions. Our results improve someknown works. 展开更多
关键词 third order nonlinear boundary value problem existence and uniqueness Volterra type operator upper and lower solutions.
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Existence and iteration of monotone positive solutions for a third-order two-point boundary value problem 被引量:5
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作者 SUN Yong-ping 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期413-419,共7页
The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″(t) + q(t)f(t,u(t),u′(t)) = 0, 0 〈 t 〈 1, u(0) = u″(0) = u′(1) = 0 is studied.... The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″(t) + q(t)f(t,u(t),u′(t)) = 0, 0 〈 t 〈 1, u(0) = u″(0) = u′(1) = 0 is studied. The iterative schemes for approximating the solutions are obtained by applying a monotone iterative method. 展开更多
关键词 third-order two-point boundary value problem monotone iterative method positive solution existence iterative scheme
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On the Existence of Positive Solution for a Nonlinear Third-order Three-point Boundary Value Problem 被引量:6
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作者 姚庆六 《Northeastern Mathematical Journal》 CSCD 2003年第3期244-248,共5页
An existence theorem of positive solution is established for a nonlinear third-order three-point boundary value problem. Here, we concentrated on the case that the nonlinear term is neither superlinear nor sublinear, ... An existence theorem of positive solution is established for a nonlinear third-order three-point boundary value problem. Here, we concentrated on the case that the nonlinear term is neither superlinear nor sublinear, and is not asymptotic at zero and infinity. 展开更多
关键词 third-order ordinary differential equation three-point boundary value problem positive solution EXISTENCE
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Triple Positive Solutions for a Third-order Three-point Boundary Value Problem 被引量:1
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作者 WU Hong-ping 《Chinese Quarterly Journal of Mathematics》 2019年第3期283-289,共7页
In this paper,we study the existence of triple positive solutions for the nonlinear third-order three-point boundary value problem ■where η∈[0,1/2) is a constant,by using a fixed-point theorem due to Avery and Pete... In this paper,we study the existence of triple positive solutions for the nonlinear third-order three-point boundary value problem ■where η∈[0,1/2) is a constant,by using a fixed-point theorem due to Avery and Peterson,we establish results of triple positive solutions to the boundary value problem,and an example is given to illustrate the importance of result obtained. 展开更多
关键词 third-ORDER three-point boundary value problem POSITIVE solutions FIXED-POINT THEOREM
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Numerical Treatment of Nonlinear Third Order Boundary Value Problem 被引量:1
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作者 Pankaj Kumar Srivastava Manoj Kumar 《Applied Mathematics》 2011年第8期959-964,共6页
In this paper, the boundary value problems for nonlinear third order differential equations are treated. A generic approach based on nonpolynomial quintic spline is developed to solve such boundary value problem. We s... In this paper, the boundary value problems for nonlinear third order differential equations are treated. A generic approach based on nonpolynomial quintic spline is developed to solve such boundary value problem. We show that the approximate solutions of such problems obtained by the numerical algorithm developed using nonpolynomial quintic spline functions are better than those produced by other numerical methods. The algorithm is tested on a problem to demonstrate the practical usefulness of the approach. 展开更多
关键词 NONLINEAR third Order BOUNDARY value Problem Nonpolynomial Quintic SPLINE Draining and Coating FLOWS
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Existence of Multiple Positive Solutions for Third-Order Three-Point Boundary Value Problem 被引量:1
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作者 Qiufeng Chen Jianli Li 《Journal of Applied Mathematics and Physics》 2019年第7期1463-1472,共10页
In this paper, we study the existence of positive solutions for a class of third-order three-point boundary value problem. By employing the fixed point theorem on cone, some new criteria to ensure the three-point boun... In this paper, we study the existence of positive solutions for a class of third-order three-point boundary value problem. By employing the fixed point theorem on cone, some new criteria to ensure the three-point boundary value problem has at least three positive solutions are obtained. An example illustrating our main result is given. Moreover, some previous results will be improved significantly in our paper. 展开更多
关键词 third-ORDER Three-Point BOUNDARY value Problem Fixed Point THEOREM Three POSITIVE Solutions
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Triple Positive Solutions to a Third-order Three-point Boundary Value Problem with p-Laplacian Operator 被引量:1
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作者 谭惠轩 封汉颍 +1 位作者 冯杏芳 杜亚涛 《Chinese Quarterly Journal of Mathematics》 2015年第1期55-65,共11页
In this paper, we consider the three-point boundary value problem (φp(uˊˊ(t)))ˊ +a(t)f(t, u(t), uˊ(t), uˊˊ(t)) = 0, t ∈ [0, 1] subject to the boundary conditions u(0) =βuˊ(0), uˊ(1) =... In this paper, we consider the three-point boundary value problem (φp(uˊˊ(t)))ˊ +a(t)f(t, u(t), uˊ(t), uˊˊ(t)) = 0, t ∈ [0, 1] subject to the boundary conditions u(0) =βuˊ(0), uˊ(1) = αuˊ(η), uˊˊ(0) = 0, where φp(s) = |s|p?2s with p 〉 1, 0 〈 α, η 〈 1 and 0 ≤ β 〈 1. Applying a fixed point theorem due to Avery and Peterson, we study the existence of at least three positive solutions to the above boundary value problem. 展开更多
关键词 third-order three-point boundary value problem positive solution fixed point theorem
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THIRD-ORDER NONLINEAR SINGULARLY PERTURBED BOUNDARY VALUE PROBLEM 被引量:1
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作者 WANG Guo-can(王国灿) +1 位作者 JIN Li(金丽) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第6期670-677,共8页
Third order singulary perturbed boundary value problem by means of differential inequality theories is studied. Based on the given results of second order nonlinear boundary value problem, the upper and lower solution... Third order singulary perturbed boundary value problem by means of differential inequality theories is studied. Based on the given results of second order nonlinear boundary value problem, the upper and lower solutions method of third order nonlinear boundary value problems by making use of Volterra type integral operator was established. Specific upper and lower solutions were constructed, and existence and asymptotic estimates of solutions under suitable conditions were obtained. The result shows that it seems to be new to apply these techniques to solving these kinds of third order singularly perturbed boundary value problem. An example is given to demonstrate the applications. 展开更多
关键词 third order boundary value problem upper and lower solutions Volterra type integral operator existence and asymptotic estimates
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The Third Initial-boundary Value Problem for a Class of Parabolic Monge-Ampère Equations
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作者 LU BO-QIANG LI FENG-QUAN 《Communications in Mathematical Research》 CSCD 2012年第1期75-90,共16页
For the more general parabolic Monge-Ampère equations defined by the operator F (D2u + σ(x)), the existence and uniqueness of the admissible solution to the third initial-boundary value problem for the equa... For the more general parabolic Monge-Ampère equations defined by the operator F (D2u + σ(x)), the existence and uniqueness of the admissible solution to the third initial-boundary value problem for the equation are established. A new structure condition which is used to get a priori estimate is established. 展开更多
关键词 parabolic Monge-Ampere equation admissible solution the third initial-boundary value problem
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Solution of the Third Kind Boundary Value Problem of Laplace’s Equation Based on Conformal Mapping
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作者 Fuqian Wang 《Journal of Applied Mathematics and Physics》 2019年第3期536-546,共11页
In order to overcome the difficulty in solving the boundary value problem of electrostatic field with complex boundary and to give a new method for solving the third boundary value problem of Laplace’s equation, in t... In order to overcome the difficulty in solving the boundary value problem of electrostatic field with complex boundary and to give a new method for solving the third boundary value problem of Laplace’s equation, in this paper, the third boundary value problem of Laplace’s equation is studied by combining conformal mapping with theoretical analysis, the several analytical solutions of third boundary value problems of Laplace’s equation are gives, the correctness of its solution is verified through computer numerical simulation, and a new idea and method for solving the third boundary value problem of Laplace’s equation is obtained. In this paper, the boundary condition of the solving domain is changed by the appropriate conformal mapping, so that the boundary value problem on the transformed domain is easy to be solved or be known, and then the third kind boundary value of the Laplace’s equation can be solved easily;its electric potential distribution is known. Furthermore, the electric field line and equipotential line are plotted by using the MATLAB software. 展开更多
关键词 The third KIND BOUNDARY value Problem Laplace’s EQUATION CONFORMAL Mapping The Electric Potential Distribution
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UNIQUENESS OF SOLUTIONS OF SINGULARLY PERTURBED BOUNDARY VALUE PROBLEMS FOR THIRD QRDER NONLINEAR ORDINARY DIFFERENTIAL EQUATIONS
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作者 赵为礼 《Acta Mathematica Scientia》 SCIE CSCD 1992年第3期304-307,共4页
By making use of the differential inequalities, in this paper we study the uniqueness of solutions of the two kinds of the singularly perturbed boundary value problems for the nonlinear third order ordinary differenti... By making use of the differential inequalities, in this paper we study the uniqueness of solutions of the two kinds of the singularly perturbed boundary value problems for the nonlinear third order ordinary differential equation with a small parameter ε>0: where i=1, 2; a(?)(ε), β(ε) and γ(ε) are functions defined on (0, ε_o], while ε_o>0 is a constant.This paper is the continuation of our works [4, 6]. 展开更多
关键词 UNIQUENESS OF SOLUTIONS OF SINGULARLY PERTURBED BOUNDARY value PROBLEMS FOR third QRDER NONLINEAR ORDINARY DIFFERENTIAL EQUATIONS BVP
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Efficient Decomposition Shooting Method for Solving Third-Order Boundary Value Problems
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作者 Nawal Al-Zaid Kholoud Alzahrani +1 位作者 Huda Bakodah Mariam Al-Mazmumy 《International Journal of Modern Nonlinear Theory and Application》 2023年第3期81-98,共18页
The present paper proposes a mathematical method to numerically treat a class of third-order linear Boundary Value Problems (BVPs). This method is based on the combination of the Adomian Decomposition Method (ADM) and... The present paper proposes a mathematical method to numerically treat a class of third-order linear Boundary Value Problems (BVPs). This method is based on the combination of the Adomian Decomposition Method (ADM) and, the modified shooting method. A complete derivation of the proposed method has been provided, in addition to its numerical implementation and, validation via the utilization of the Runge-Kutta method and, other existing methods. The method has been applied to diverse test problems and turned out to perform remarkably. Lastly, the simulated numerical results have been graphically illustrated and, also supported by some absolute error comparison tables. 展开更多
关键词 Linear third Order BVPs Shooting Method Adomian Decomposition Method Two-Point Boundary value Problem
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Existence Results of Third Order Multi-Point Boundary Value Problem at Resonance 被引量:3
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作者 杜增吉 白占兵 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期449-452,共4页
A kind of third order multi-point boundary value problems, x'''( ι) = f( t, x ( t ), x" ( t ), x''' ( t ) ) + m 2 e(t),t∈(0, 1),x(0)=ax(ξ),x'(0)-0,x(l)= ^m2∑j=1 βjx(ηj), fεC[0,... A kind of third order multi-point boundary value problems, x'''( ι) = f( t, x ( t ), x" ( t ), x''' ( t ) ) + m 2 e(t),t∈(0, 1),x(0)=ax(ξ),x'(0)-0,x(l)= ^m2∑j=1 βjx(ηj), fεC[0, 1]×R^3, e(t)∈L^1[0, 1],a≥0, is considered, all theβj's have not the same sign, 0〈ξ〈 l, 0〈η1〈 η2〈… 〈ηm.2〈 1. By using the coincidence degree theory, some existence theorems for the problems at resonance are obtained. 展开更多
关键词 multi-point boundary value problem RESONANCE coincidence degree theory
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SINGULAR PERTURBATION OF BOUNDARY VALUE PROBLEM FOR QUASILINEAR THIRD-ORDER ORDINARY DIFFERENTIAL EQUATIONS INVOLVING TWO SMALL PARAMETERS 被引量:2
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作者 林苏榕 田根宝 林宗池 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第2期229-236,共8页
The singularly perturbed boundary value problem for quasilinear third-order ordinary differential equation involving two small parameters has been considered. For the three cases epsilon/mu (2) --> 0(mu --> 0), ... The singularly perturbed boundary value problem for quasilinear third-order ordinary differential equation involving two small parameters has been considered. For the three cases epsilon/mu (2) --> 0(mu --> 0), mu (2)/epsilon --> 0(epsilon --> 0) and epsilon = mu (2), the formal asymptotic solutions are constructed by the method of two steps expansions and the existences of solution are proved by using the differential inequality method. In addition, the uniformly valid estimations of the remainder term are given as well. 展开更多
关键词 two-parameters singular perturbation boundary value problem asymptotic expansion
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Multiple Positive Solutions of Boundary Value Problems for Systems of Nonlinear Third-Order Differential Equations 被引量:2
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作者 Yaohong LI Xiaoyan ZHANG 《Journal of Mathematical Research with Applications》 CSCD 2013年第3期321-329,共9页
In this paper, we consider boundary value problems for systems of nonlinear third- order differential equations. By applying the fixed point theorems of cone expansion and compression of norm type and Leggett-Williams... In this paper, we consider boundary value problems for systems of nonlinear third- order differential equations. By applying the fixed point theorems of cone expansion and compression of norm type and Leggett-Williams fixed point theorem, the existence of multiple positive solutions is obtained. As application, we give some examples to demonstrate our results. 展开更多
关键词 boundary value problem multiple positive solutions fixed-point theorem.
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SOME NECESSARY AND SUFFICIENT CONDITIONS FOR EXISTENCE OF POSITIVE SOLUTIONS FOR THIRD ORDER SINGULAR SUBLINEAR MULTI-POINT BOUNDARY VALUE PROBLEMS 被引量:5
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作者 韦忠礼 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1795-1810,共16页
We mainly study the existence of positive solutions for the following third order singular multi-point boundary value problem{x^(3)(t) + f(t, x(t), x′(t)) = 0, 0 〈 t 〈 1,x(0)-∑i=1^m1 αi x(ξi) = 0... We mainly study the existence of positive solutions for the following third order singular multi-point boundary value problem{x^(3)(t) + f(t, x(t), x′(t)) = 0, 0 〈 t 〈 1,x(0)-∑i=1^m1 αi x(ξi) = 0, x′(0)-∑i=1^m2 βi x′(ηi) = 0, x′(1)=0,where 0 ≤ ai≤∑i=1^m1 αi 〈 1, i = 1, 2, ···, m1, 0 〈 ξ1〈 ξ2〈 ··· 〈 ξm1〈 1, 0 ≤βj≤∑i^m2=1βi〈1,J=1,2, ···, m2, 0 〈 η1〈 η2〈 ··· 〈 ηm2〈 1. And we obtain some necessa βi 〈=11, j = 1,ry and sufficient conditions for the existence of C^1[0, 1] and C^2[0, 1] positive solutions by constructing lower and upper solutions and by using the comparison theorem. Our nonlinearity f(t, x, y)may be singular at x, y, t = 0 and/or t = 1. 展开更多
关键词 boundary value problems positive solutions lower and upper solutions comparison theorem
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Solvability of Third-order Three-point Boundary Value Problems with Caratheodory Nonlinearity 被引量:1
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作者 YAO QING-LIU 《Communications in Mathematical Research》 CSCD 2012年第3期209-217,共9页
A class of third-order three-point boundary value problems is considered, where the nonlinear term is a Caratheodory function. By introducing a height function and considering the imtegration of this height function, ... A class of third-order three-point boundary value problems is considered, where the nonlinear term is a Caratheodory function. By introducing a height function and considering the imtegration of this height function, an existence theorem of solution is proved when the limit growth function exists. The main tools are the Lebesgue dominated convergence theorem and the Schauder fixed point theorem. 展开更多
关键词 nonliaear ordinary differential equation multi-point boundary value problem EXISTENCE
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Existence of Positive Solutions for a Third-Order Multi-Point Boundary Value Problem 被引量:2
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作者 A. Guezane-Lakoud L. Zenkoufi 《Applied Mathematics》 2012年第9期1008-1013,共6页
By using Leray-Schauder nonlinear alternative, Banach contraction theorem and Guo-Krasnosel’skii theorem, we discuss the existence, uniqueness and positivity of solution to the third-order multi-point nonhomogeneous ... By using Leray-Schauder nonlinear alternative, Banach contraction theorem and Guo-Krasnosel’skii theorem, we discuss the existence, uniqueness and positivity of solution to the third-order multi-point nonhomogeneous boundary value problem (BVP1): where for The interesting point lies in the fact that the nonlinear term is allowed to depend on the first order derivative . 展开更多
关键词 Guo’s Fixed POINT THEOREM Three POINT Boundary value Problem Positive Solution LERAY SCHAUDER Non-Linear Alternative CONTRACTION Principle
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Significance and prognostic value of lysosomal enzyme activities measured in surgically operated adenocarcinomas of the gastroesophageal junction and squamous cell carcinomas of the lower third of esophagus 被引量:1
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作者 Aron Altorjay Balazs Paal +3 位作者 Nicolette Sohar Janos Kiss Imre Szanto Istvan Sohar 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第37期5751-5756,共6页
AIM: To establish whether there are fundamental differences in the biochemistries of adenocarcinomas of the gastroesophageal junction (GEJ) and the squamous cell carcinomas of the lower third of the esophagus (LTE... AIM: To establish whether there are fundamental differences in the biochemistries of adenocarcinomas of the gastroesophageal junction (GEJ) and the squamous cell carcinomas of the lower third of the esophagus (LTE). METHODS: Between February 1, 1997 and February 1, 2000, we obtained tissue samples at the moment of resection from 54 patients for biochemical analysis. The full set of data could be comprehensively analyzed in 47 of 54 patients' samples (81%). Of these, 29 were adenocarcinomas of the GEJ Siewert type Ⅰ (n = 8), type Ⅱ (n = 12), type Ⅲ (n = 9), and 18 presented as squamous cell carcinomas of the LTE. We evaluated the mean values of 11-lysosomal enzyme and 1-cytosol protease activities of the tumorous and surrounding mucosae as well as their relative activities, measured as the ratio of activity in tumor and normal tissues from the same patient. These data were further analyzed to establish the correlation with tumor localization, TNM stage (lymph-node involvement), histological type (papillary, signet-ring cell, tubular), state of differentiation (good, moderate, poor), and survival (≤24 or ≥24 mo). RESULTS: In adenocarcinomas, the activity of α-mannosidase (AMAN), cathepsin B (CB) and dipeptidyl-peptidase Ⅰ (DPP Ⅰ) increased significantly as compared to the normal gastric mucosa. In squamous cell carcinomas of the esophagus, we also found a significant difference in the activity of cathepsin L and tripeptidyl-peptidase Ⅰ in addition to these three. There was a statistical correlation of AMAN, CB, and DPP Ⅰ activity between the level of differentiation of adenocarcinomas of the GEJ and lymph node involvement,because tumors with no lymph node metastases histologically confirmed as well-differentiated, showed a significantly lower activity. The differences in CB and DPP Ⅰ activity correlated well with the differences in survival rates, since the CB and DPP Ⅰ values of those who died within 24 mo following surgical intervention were significantly higher than of those who survived for 2 years or more. CONCLUSION: Adenocarcinomas of the GEJ form a homogenous group from a tumor-biochemical aspect, and differ from the biochemical characteristics of squamous cell carcinomas of the LTE on many points. When adenocarcinomas of the GEJs are examined at the preoperative phase, the ratio of the performed AMAN, CB, and DPP Ⅰ enzymatic activity of the tissue sample from the tumor and adjacent intact mucosa within 2 cm of the tumor may have a prognostic value even in the preoperative examination period, and may indicate that ranking of these patients into the neo-adjuvant treatment group should be considered. 展开更多
关键词 Prognostic value Lysosomal enzymes Cardiac adenocarcinomas Siewert classification Esophageal squamous cell carcinoma
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