The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local and nonlocal balance equations for micromorphic continuum mechanics and couple stress theor...The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local and nonlocal balance equations for micromorphic continuum mechanics and couple stress theory. The desired results for micromorphic continuum mechanics and couple stress theory are naturally obtained via direct transitions and reductions from the coupled conservation law of energy for micropolar continuum theory, respectively. The basic balance laws and equations for micromorphic continuum mechanics and couple stress theory are constituted by combining these results derived here and the traditional conservation laws and equations of mass and microinertia and the entropy inequality. The incomplete degrees of the former related continuum theories are clarified. Finally, some special cases are conveniently derived.展开更多
A set of basic deformation modes for hybrid stress finite elements are directly derived from the element displacement field. Subsequently, by employing the so-called united orthogonal conditions, a new orthogonalizati...A set of basic deformation modes for hybrid stress finite elements are directly derived from the element displacement field. Subsequently, by employing the so-called united orthogonal conditions, a new orthogonalization method is proposed. The result- ing orthogonal basic deformation modes exhibit simple and clear physical meanings. In addition, they do not involve any material parameters, and thus can be efficiently used to examine the element performance and serve as a unified tool to assess different hybrid elements. Thereafter, a convenient approach for the identification of spurious zero-energy modes is presented using the positive definiteness property of a flexibility matrix. More- over, based on the orthogonality relationship between the given initial stress modes and the orthogonal basic deformation modes, an alternative method of assumed stress modes to formulate a hybrid element free of spurious modes is discussed. It is found that the orthogonality of the basic deformation modes is the sufficient and necessary condition for the suppression of spurious zero-energy modes. Numerical examples of 2D 4-node quadrilateral elements and 3D 8-node hexahedral elements are illustrated in detail to demonstrate the efficiency of the proposed orthogonal basic deformation mode method.展开更多
Four weeks of uncertain stress was used to establish an animal model of chronic stress. Basic fibroblast growth factor was injected daily for 15 days following stress induction. Cell morphology in the hippocampal CA3 ...Four weeks of uncertain stress was used to establish an animal model of chronic stress. Basic fibroblast growth factor was injected daily for 15 days following stress induction. Cell morphology in the hippocampal CA3 region of chronic stress mice revealed cell damage. Nitric oxide content and calcium concentration were significantly increased in the hippocampus, and learning and memory functions were significantly decreased. After basic fibroblast growth factor intervention, Ca2~ overload was decreased and neuronal damage was relieved in hippocampal neurons, which improved learning and memory functions in chronic stress mice. Latency was prolonged and the number of errors was decreased in a passive avoidance test.展开更多
Stress urinary incontinence(SUI)is a common disorder that affects a large number of women and their quality of life.The aim of SUI therapy is to restore the existing urethral function via physical therapy,biofeedback,...Stress urinary incontinence(SUI)is a common disorder that affects a large number of women and their quality of life.The aim of SUI therapy is to restore the existing urethral function via physical therapy,biofeedback,pelvic floor rehabilitation,pharmacological therapy,bulking agents and surgical approaches.Currently,the gold standard for the management of SUI is the tensionfree vaginal sling,which provides structural support to the female urethra.However,even minimally invasive surgical procedure such as"slings"carries risks for the patients,lost efficacy over the time and has long-term complications.For this reason,new therapeutic modalities are needed.Cell therapy has been emerged as an alternative to be used on the treatment of different diseases.The use of stem cells as a therapeutic option for SUI is an attractive alternative because,theoretically,injected cells could restore functional muscle cells and aid in sphincter closure in women with sphincterassociated incontinence.This study aims to review the current literature regarding evidences for using stem cell therapy on stress urinary incontinence in women.展开更多
目的:探讨水凝胶递送碱性成纤维细胞生长因子(bFGF)对氧糖剥夺(OGD)后小鼠成纤维NIH3T3细胞功能的影响,并阐明负载bFGF的水凝胶对OGD条件下成纤维细胞氧化应激反应的改善作用。方法:制备bFGF明胶水凝胶,将对数生长期NIH3T3细胞分为空白...目的:探讨水凝胶递送碱性成纤维细胞生长因子(bFGF)对氧糖剥夺(OGD)后小鼠成纤维NIH3T3细胞功能的影响,并阐明负载bFGF的水凝胶对OGD条件下成纤维细胞氧化应激反应的改善作用。方法:制备bFGF明胶水凝胶,将对数生长期NIH3T3细胞分为空白组、20%明胶组和20%明胶+戊二醛组,采用CCK-8法检测6、12和24 h水凝胶浸出液共培养的NIH3T3细胞活性。将NIH3T3细胞分为对照组、OGD组和OGD+不同质量bFGF负载组(OGD+1 ng bFGF组、OGD+10 ng bFGF组和OGD+100 ng bFGF组)。采用Western blotting法检测各组细胞中α-平滑肌肌动蛋白(α-SMA)、Ⅰ型胶原蛋白和Ⅲ型胶原蛋白表达水平。检测各组细胞中丙二醛(MDA)水平和乳酸脱氢酶(LDH)及超氧化物歧化酶(SOD)活性。采用酶联免疫吸附试验(ELISA)法检测bFGF体外释放率。结果:CCK-8法检测,与空白组比较,不同浸出时间20%明胶组和20%明胶+戊二醛组NIH3T3细胞活性差异无统计学意义(P>0.05)。Western blotting法检测,与对照组比较,OGD组NIH3T3细胞中α-SMA和Ⅰ型胶原蛋白表达水平明显升高(P<0.05或P<0.01);与OGD组比较,OGD+1 ng bFGF组、OGD+10 ng bFGF组和OGD+100 ng bFGF组NIH3T3细胞中α-SMA蛋白表达水平均明显降低(P<0.01),Ⅰ型胶原蛋白表达水平均明显降低(P<0.05或P<0.01),并呈剂量依赖性。与对照组比较,OGD组NIH3T3细胞中MDA水平和LDH活性升高(P<0.05),SOD活性降低(P<0.05)。与OGD组比较,OGD+1 ng bFGF组NIH3T3细胞中MDA水平和LDH活性降低(P<0.05),SOD活性升高(P<0.05)。ELISA法检测,在4 h内约10%bFGF由水凝胶中释放,在12 h内约15%bFGF由水凝胶中释放,在24 h内约21%bFGF由水凝胶中释放。结论:负载bFGF的水凝胶可以调控OGD条件下成纤维细胞的转化,抑制成纤维细胞Ⅰ型胶原蛋白表达,并改善细胞氧化应激反应,且该系统具有一定的持续释药能力。展开更多
文摘The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local and nonlocal balance equations for micromorphic continuum mechanics and couple stress theory. The desired results for micromorphic continuum mechanics and couple stress theory are naturally obtained via direct transitions and reductions from the coupled conservation law of energy for micropolar continuum theory, respectively. The basic balance laws and equations for micromorphic continuum mechanics and couple stress theory are constituted by combining these results derived here and the traditional conservation laws and equations of mass and microinertia and the entropy inequality. The incomplete degrees of the former related continuum theories are clarified. Finally, some special cases are conveniently derived.
基金Project supported by the National Natural Science Foundation of China(No.10972188)the Fundamental Research Funds for the Central Universities of China(No.2010121073)the Scientific Program of Fujian Province of China(No.2007F3096)
文摘A set of basic deformation modes for hybrid stress finite elements are directly derived from the element displacement field. Subsequently, by employing the so-called united orthogonal conditions, a new orthogonalization method is proposed. The result- ing orthogonal basic deformation modes exhibit simple and clear physical meanings. In addition, they do not involve any material parameters, and thus can be efficiently used to examine the element performance and serve as a unified tool to assess different hybrid elements. Thereafter, a convenient approach for the identification of spurious zero-energy modes is presented using the positive definiteness property of a flexibility matrix. More- over, based on the orthogonality relationship between the given initial stress modes and the orthogonal basic deformation modes, an alternative method of assumed stress modes to formulate a hybrid element free of spurious modes is discussed. It is found that the orthogonality of the basic deformation modes is the sufficient and necessary condition for the suppression of spurious zero-energy modes. Numerical examples of 2D 4-node quadrilateral elements and 3D 8-node hexahedral elements are illustrated in detail to demonstrate the efficiency of the proposed orthogonal basic deformation mode method.
基金the "Eleventh Five-Year" Scientific and Technological Research Projects of the Education Department of Jilin Province, No. [2008]137
文摘Four weeks of uncertain stress was used to establish an animal model of chronic stress. Basic fibroblast growth factor was injected daily for 15 days following stress induction. Cell morphology in the hippocampal CA3 region of chronic stress mice revealed cell damage. Nitric oxide content and calcium concentration were significantly increased in the hippocampus, and learning and memory functions were significantly decreased. After basic fibroblast growth factor intervention, Ca2~ overload was decreased and neuronal damage was relieved in hippocampal neurons, which improved learning and memory functions in chronic stress mice. Latency was prolonged and the number of errors was decreased in a passive avoidance test.
文摘Stress urinary incontinence(SUI)is a common disorder that affects a large number of women and their quality of life.The aim of SUI therapy is to restore the existing urethral function via physical therapy,biofeedback,pelvic floor rehabilitation,pharmacological therapy,bulking agents and surgical approaches.Currently,the gold standard for the management of SUI is the tensionfree vaginal sling,which provides structural support to the female urethra.However,even minimally invasive surgical procedure such as"slings"carries risks for the patients,lost efficacy over the time and has long-term complications.For this reason,new therapeutic modalities are needed.Cell therapy has been emerged as an alternative to be used on the treatment of different diseases.The use of stem cells as a therapeutic option for SUI is an attractive alternative because,theoretically,injected cells could restore functional muscle cells and aid in sphincter closure in women with sphincterassociated incontinence.This study aims to review the current literature regarding evidences for using stem cell therapy on stress urinary incontinence in women.
文摘目的:探讨水凝胶递送碱性成纤维细胞生长因子(bFGF)对氧糖剥夺(OGD)后小鼠成纤维NIH3T3细胞功能的影响,并阐明负载bFGF的水凝胶对OGD条件下成纤维细胞氧化应激反应的改善作用。方法:制备bFGF明胶水凝胶,将对数生长期NIH3T3细胞分为空白组、20%明胶组和20%明胶+戊二醛组,采用CCK-8法检测6、12和24 h水凝胶浸出液共培养的NIH3T3细胞活性。将NIH3T3细胞分为对照组、OGD组和OGD+不同质量bFGF负载组(OGD+1 ng bFGF组、OGD+10 ng bFGF组和OGD+100 ng bFGF组)。采用Western blotting法检测各组细胞中α-平滑肌肌动蛋白(α-SMA)、Ⅰ型胶原蛋白和Ⅲ型胶原蛋白表达水平。检测各组细胞中丙二醛(MDA)水平和乳酸脱氢酶(LDH)及超氧化物歧化酶(SOD)活性。采用酶联免疫吸附试验(ELISA)法检测bFGF体外释放率。结果:CCK-8法检测,与空白组比较,不同浸出时间20%明胶组和20%明胶+戊二醛组NIH3T3细胞活性差异无统计学意义(P>0.05)。Western blotting法检测,与对照组比较,OGD组NIH3T3细胞中α-SMA和Ⅰ型胶原蛋白表达水平明显升高(P<0.05或P<0.01);与OGD组比较,OGD+1 ng bFGF组、OGD+10 ng bFGF组和OGD+100 ng bFGF组NIH3T3细胞中α-SMA蛋白表达水平均明显降低(P<0.01),Ⅰ型胶原蛋白表达水平均明显降低(P<0.05或P<0.01),并呈剂量依赖性。与对照组比较,OGD组NIH3T3细胞中MDA水平和LDH活性升高(P<0.05),SOD活性降低(P<0.05)。与OGD组比较,OGD+1 ng bFGF组NIH3T3细胞中MDA水平和LDH活性降低(P<0.05),SOD活性升高(P<0.05)。ELISA法检测,在4 h内约10%bFGF由水凝胶中释放,在12 h内约15%bFGF由水凝胶中释放,在24 h内约21%bFGF由水凝胶中释放。结论:负载bFGF的水凝胶可以调控OGD条件下成纤维细胞的转化,抑制成纤维细胞Ⅰ型胶原蛋白表达,并改善细胞氧化应激反应,且该系统具有一定的持续释药能力。
