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Risk factors for recurrence of common bile duct stones after surgical treatment and effect of ursodeoxycholic acid intervention
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作者 Wei-Hong Yuan Zheng Zhang +2 位作者 Qi Pan Bo-Neng Mao Tao Yuan 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期103-112,共10页
BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)is an accurate diagnostic method for choledocholithiasis and treatment option for stone removal.Additionally,ursodeoxycholic acid(UDCA)can dissolve choles... BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)is an accurate diagnostic method for choledocholithiasis and treatment option for stone removal.Additionally,ursodeoxycholic acid(UDCA)can dissolve cholesterol stones and prevent their development and reappearance by lowering the cholesterol concen-tration in bile.Despite these treatment options,there are still patients who experience stone recurrence.The clinical data of 100 patients with choledochal stones who were hospitalized at the Yixing People’s Hospital and underwent ERCP for successful stone extraction between June 2020 and December 2022 were retrospectively collected.According to the post-ERCP treatment plan,100 patients were classified into UDCA(n=47)and control(n=53)groups.We aimed to assess the clinical efficacy and rate of relapse in the two patient populations.We then collected information(basic demographic data,clinical characteristics,and serum biochemical indicators)and determined the factors contributing to relapse using logistic regression analysis.Our secondary goal was to determine the effects of UDCA on liver function after ERCP.Compared to the control group,the UDCA group demonstrated a higher clinical effectiveness rate of 92.45%vs 78.72%(P<0.05).No significant differences were observed in liver function indices,including total bilirubin,direct bilirubin,gamma-glutamyl transpeptidase,alanine aminotransferase,alkaline phosphatase,and aspartate aminotransferase,between the two groups before treatment.After treatment,all liver function indices were significantly reduced.Comparing the control vs UDCA groups,the UDCA group exhibited significantly lower levels of all indices(55.39±6.53 vs 77.31±8.52,32.10±4.62 vs 45.39±5.69,142.32±14.21 vs 189.63±16.87,112.52±14.25 vs 149.36±15.36,122.61±16.00 vs 171.33±22.09,96.98±10.44 vs 121.35±11.57,respectively,all P<0.05).The stone recurrence rate was lower in the UDCA group(13.21%)in contrast with the control group(44.68%).Periampullary diverticula(OR:6.00,95%CI:1.69-21.30),maximum stone diameter(OR:1.69,95%CI:1.01-2.85),stone quantity>3(OR:4.23,95%CI:1.17-15.26),and positive bile culture(OR:7.61,95%CI:2.07-27.91)were independent factors that influenced the relapse of common bile duct stones after ERCP(P<0.05).Furthermore,postoperative UDCA was identified as a preventive factor(OR:0.07;95%CI:0.08-0.09).CONCLUSION The intervention effect of UDCA after ERCP for common bile duct stones is adequate,providing new research directions and references for the prevention and treatment of stone recurrence. 展开更多
关键词 Endoscopic retrograde cholangiopancreatography RECURRENCE Ursodeoxycholic acid Common bile duct stones Clinical effective rate Risk factors
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Clinical Study on Respiratory Medicine Treatment of Chronic Obstructive Pulmonary Disease Combined with Respiratory Failure
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作者 Jianhua Yu 《Journal of Clinical and Nursing Research》 2024年第5期293-298,共6页
Objective:To explore the respiratory medicine treatment methods for treating chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:70 cases of COPD patients with combined respiratory fai... Objective:To explore the respiratory medicine treatment methods for treating chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:70 cases of COPD patients with combined respiratory failure admitted to our hospital from January 2021 to January 2023 were selected as the study subjects,and randomly divided into the control group and the experimental group,each with 35 cases.The control group received only conventional treatment,and the experimental group received non-invasive positive pressure ventilation,and the treatment effects and changes in the levels of IL-18,hs-CRP,and CES2 inflammatory factors were observed and evaluated in the two groups.Results:There was no significant difference between the general data of the two groups(P>0.05);after treatment,the total effective rate of clinical efficacy of the observation group(91.43%)was significantly higher than that of the control group(71.43%),and the difference showed a significant correlation(P<0.05);after treatment,the level of inflammatory factor of the observation group was significantly reduced compared with that of the control group,and the difference showed a highly significant correlation(P<0.001).Conclusion:The non-invasive positive pressure ventilation treatment program significantly improves the therapeutic effect,effectively controls the level of inflammatory factors,and improves the health status of patients when dealing with patients with chronic obstructive pulmonary disease accompanied by respiratory failure,showing a good clinical application prospect. 展开更多
关键词 Chronic obstructive pulmonary disease Respiratory failure Non-invasive positive pressure ventilation therapeutic effect Inflammatory factor
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Laser-assisted Simulation of Dose Rate Effects of Wide Band Gap Semiconductor Devices
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作者 TANG Ge XIAO Yao +3 位作者 SUN Peng LIU Jingrui ZHANG Fuwang LI Mo 《原子能科学技术》 EI CAS CSCD 北大核心 2023年第12期2314-2325,共12页
Laser-assisted simulation technique has played a crucial role in the investigation of dose rate effects of silicon-based devices and integrated circuits,due to its exceptional advantages in terms of flexibility,safety... Laser-assisted simulation technique has played a crucial role in the investigation of dose rate effects of silicon-based devices and integrated circuits,due to its exceptional advantages in terms of flexibility,safety,convenience,and precision.In recent years,wide band gap materials,known for their strong bonding and high ionization energy,have gained increasing attention from researchers and hold significant promise for extensive applications in specialized environments.Consequently,there is a growing need for comprehensive research on the dose rate effects of wide band gap materials.In response to this need,the use of laser-assisted simulation technology has emerged as a promising approach,offering an effective means to assess the efficacy of investigating these materials and devices.This paper focused on investigating the feasibility of laser-assisted simulation to study the dose rate effects of wide band gap semiconductor devices.Theoretical conversion factors for laser-assisted simulation of dose rate effects of GaN-based and SiC-based devices were been provided.Moreover,to validate the accuracy of the conversion factors,pulsed laser and dose rate experiments were conducted on GaN-based and SiC-based PIN diodes.The results demonstrate that pulsed laser radiation andγ-ray radiation can produce highly similar photocurrent responses in GaN-based and SiC-based PIN diodes,with correlation coefficients of 0.98 and 0.974,respectively.This finding reaffirms the effectiveness of laser-assisted simulation technology,making it a valuable complement in studying the dose rate effects of wide band gap semiconductor devices. 展开更多
关键词 laser-assisted simulation dose rate effect wide band gap semiconductor conversion factor
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Experimental investigation of rigid confinement effects of radial strain on dynamic mechanical properties and failure modes of concrete 被引量:4
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作者 Pengfei Liu Xiaoping Zhou Qihu Qian 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期939-951,共13页
In this study,to confirm the effect of confining pressure on dynamic mechanical behavior and failure modes of concrete,a split Hopkinson pressure bar dynamic loading device was utilized to perform dynamic compressive ... In this study,to confirm the effect of confining pressure on dynamic mechanical behavior and failure modes of concrete,a split Hopkinson pressure bar dynamic loading device was utilized to perform dynamic compressive experiments under confined and unconfined conditions.The confining pressure was achieved by applying a lateral metal sleeve on the testing specimen which was loaded in the axial direction.The experimental results prove that dynamic peak axial stress,dynamic peak lateral stress,and peak axial strain of concrete are strongly sensitive to the strain rate under confined conditions.Moreover,the failure patterns are significantly affected by the stress-loading rate and confining pressure.Concrete shows stronger strain rate effects under an unconfined condition than that under a confined condition.More cracks are created in concrete subjected to uniaxial dynamic compression at a higher strain rate,which can be explained by a thermal-activated mechanism.By contrast,crack generation is prevented by confinement.Fitting formulas of the dynamic peak stress and dynamic peak axial strain are established by considering strain rate effects(50–250 s-1)as well as the dynamic confining increase factor(DIFc). 展开更多
关键词 Strain rate effect Multiaxial loading Dynamic peak axial stress thermo-activated mechanism Dynamic increase factor
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Numerical Derivation of Strain Rate Effects on Material Properties of Masonry with Solid Clay Bricks 被引量:4
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作者 WEI Xueying HAO Hong 《Transactions of Tianjin University》 EI CAS 2006年第B09期147-151,共5页
In this paper, numerical method is used to study the strain rate effect on masonry materials. A typical unit of masonry is selected to serve as a representative volume element (RVE). Numerical model of RVE is establis... In this paper, numerical method is used to study the strain rate effect on masonry materials. A typical unit of masonry is selected to serve as a representative volume element (RVE). Numerical model of RVE is established with detailed distinctive modeling of brick and mortar with their respective dynamic material properties obtained from laboratory tests. The behavior of brick and mortar are characterized by a dynamic damage model that accounts for rate-sensitive and pressuredependent properties of masonry materials. Dynamic loads of different loading rates are applied to RVE. The equivalent homogenized uniaxial compressive strength, threshold strain and elastic modulus in three directions of the masonry are derived from the simulated responses of the RVE. The strain rate effect on the masonry material with clay brick and mortar, such as the dynamic increase factor (DIF) of the ultimate strength and elastic modulus as a function of strain rate are derived from the numerical results. 展开更多
关键词 圬工结构 应变速率 动力增量因子 弹性模数 极限强度
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Reliability analysis of k-out-of-n system with load-sharing and failure propagation effect
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作者 CHEN Ying MA Qichao +1 位作者 WANG Ze LI Yingyi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第5期1221-1231,共11页
In complex systems,functional dependency and physical dependency may have a coupling effect.In this paper,the reliability of a k-out-of-n system is analyzed considering load-sharing effect and failure mechanism(FM)pro... In complex systems,functional dependency and physical dependency may have a coupling effect.In this paper,the reliability of a k-out-of-n system is analyzed considering load-sharing effect and failure mechanism(FM)propagation.Three types of FMs are considered and an accumulative damage model is proposed to illustrate the system behavior of the k-out-of-n system and the coupling effect between load-sharing effect and FM propagation effect.A combinational algorithm based on Binary decision diagram(BDD)and Monte-Carlo simulation is presented to evaluate the complex system behavior and reliability of the k-out-of-n system.A current stabilizing system that consists of a 3-out-of-6 subsystem with FM propagation effect is presented as a case to illustrate the complex behavior and to verify the applicability of the proposed method.Due to the coupling effect change,the main mechanism and failure mode will be changed,and the system lifetime is shortened.Reasons are analyzed and results show that different sensitivity factors of three different FMs lead to the change of the development rate,thus changing the failure scenario.Neglecting the coupling effect may lead to an incomplete and ineffective measuring and monitoring plan.Design strategies must be adopted to make the FM propagation insensitive to load-sharing effect. 展开更多
关键词 k-out-of-n system load-sharing effect failure mechanism propagation damage factor model combinational algorithm
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CONTRACEPTIVE PREVALENCE AND USE-EFFECTIVENESS OF MARRIED WOMEN OF REPRODUCTIVE AGE IN THE RURAL AREAS OF SHAANXI PROVINCE
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作者 高万珍 冯忠蕙 《Journal of Pharmaceutical Analysis》 CAS 1994年第2期153-158,共6页
In order to study women's fertility and behavior in shaanxi Province, we used PPS method to sample Weinan, Nanzheng and Yan'an counties which represent the centre, south and north of Shaanxi respectively from ... In order to study women's fertility and behavior in shaanxi Province, we used PPS method to sample Weinan, Nanzheng and Yan'an counties which represent the centre, south and north of Shaanxi respectively from February to March in 1990. 3253 qualified married women of reproductive age were available. Because contraception is one of the most imPOrtant proximate determinants in inhibiting fertility, we just measured contraceptive prevalence and use-effectiveness among different subgroups in this dissertation. The results indicated that the prevalence rate of contraception was 75. 9 %, prevalence of different contraceptive methods varied widely: it was 43. 5% in IUD, 27. 7% in women'sterilization, 2. 0% in pill, 1.9% in men's sterilization, 0. 2% in condom and 0. 7 % in other methods, The average use-effectiveness of three methods was 0. 9965 for sterilization,0. 8792 for IUD and 0. 8520 for other methods and total average use-effectiveness was 0. 9251. 展开更多
关键词 CONTRACEPTION contraceptive prevalence rate contraceptive use-effectiveness 1-yearcumulative failure rate of contraception multiple decrement life table
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Risk factors for secondary infection after liver failure and effect of comprehensive nursing intervention
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作者 Wen-Wen Zhang Li Chen Yu-Fang Wu 《World Journal of Clinical Cases》 SCIE 2024年第22期4956-4964,共9页
BACKGROUND In patients with liver failure(LF),the high rate of secondary infections,which are associated with poor prognosis,highlights the clinical significance of understanding the underlying risk factors and implem... BACKGROUND In patients with liver failure(LF),the high rate of secondary infections,which are associated with poor prognosis,highlights the clinical significance of understanding the underlying risk factors and implementing targeted intervention programs.AIM To investigate risk factors for secondary infections in patients with LF and evaluate the effectiveness of comprehensive nursing interventions.METHODS This retrospective study included 64 patients with LF,including 32 with and 32 without secondary infections.A questionnaire was used to collect data on age;laboratory parameters,including total and direct bilirubin,prothrombin time,blood ammonia,and other biochemical parameters;invasive procedures;and complications.Patients with secondary infections received comprehensive nursing intervention in addition to routine nursing care,whereas those without secondary infections received only routine nursing care to compare the effect of nursing intervention on outcomes.RESULTS The infection rate,which was not associated with age or complications,was significantly associated with biochemical parameters and invasive procedures(P<0.05).The infection rate was 61.6%in patients who had undergone invasive procedures and 32.1%in those who had not undergone invasive procedures during the hospital stay.The infection rate was also significantly associated with the type of LF(P<0.05),with the lowest rate observed in patients with acute LF and the highest rate observed in those with subacute LF.The nursing satisfaction rate was 58.3%in the uninfected group and 91.7%in the infected group,indicating significantly higher satisfaction in the infected group(P<0.05).CONCLUSION In patients with LF,the rate of secondary infections was high and associated with biochemical parameters and type of LF.Comprehensive nursing intervention can improve patient satisfaction. 展开更多
关键词 Liver failure Secondary infection Comprehensive nursing Risk factors Intervention effect
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The Optimization of Preventive Maintenance Scheduling for Production Machine of Production System in Finite Time Horizon
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作者 韩帮军 潘军 +1 位作者 范秀敏 马登哲 《Journal of Donghua University(English Edition)》 EI CAS 2004年第1期112-116,共5页
The recursion relation of preventive maintenance (PM) cycle is built up concerning the concept of effective age and age setback factor proposed in this paper, which illustrates the dynamic relationship between failure... The recursion relation of preventive maintenance (PM) cycle is built up concerning the concept of effective age and age setback factor proposed in this paper, which illustrates the dynamic relationship between failure rate and preventive maintenance activity. And the nonlinear optimal PM policy model satisfying the reliability constraints in finite time horizon following Weibull distribution is proposed. The model built in this paper avoids the shortcoming of steady analytical PM model in infinite time horizon and can be used to aid scheduling the maintenance plan and providing decision supporting for job shop scheduling. 展开更多
关键词 预防性维护 故障因子 非线性优化 制造机床 有限时间层位
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Numerical study on dynamic properties of rubberised concrete with different rubber contents
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作者 Lei Pan Hong Hao +1 位作者 Jian Cui Thong M.Pham 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期228-240,共13页
As a green environmentally-friendly material,rubberised concrete(Ru C),which has the characteristics of low elastic modulus,large deformation capacity,high damping,good energy dissipation and good crack resistance,has... As a green environmentally-friendly material,rubberised concrete(Ru C),which has the characteristics of low elastic modulus,large deformation capacity,high damping,good energy dissipation and good crack resistance,has attracted extensive attention and research in the civil engineering discipline.However,most of existing studies are based on experimental tests on Ru C material properties,and there has been no numerical study based on meso-scale modelling of Ru C yet.To more comprehensively investigate the Ru C dynamic material properties without conducting intensive experimental tests,this study developed a high-fidelity meso-scale model considering coarse and fine aggregates and rubber crumbs to numerically investigate the mechanical properties of rubberised concrete under different strain rates.The meso-scale model was verified against both quasi-static compressive testing data and Split Hopkinson Pressure Bar(SHPB)dynamic testing data.Using the verified numerical model,the dynamic properties of rubberised concrete with various rubber content(0%-30%)under different strain rates were studied.The numerical results show that the developed meso-scale model can use to predict the static and dynamic properties of rubberised concrete with high accuracy.The dynamic compressive strength of the rubberised concrete increases with the increment of the strain rate,and the strain rate sensitivity increases with the rubber content ranging from 0 to 30%.Based on intensive numerical simulation data,empirical DIFs is used as a function of strain rate and rubber content to predict the dynamic strength of rubberised concrete. 展开更多
关键词 Rubberised concrete Meso-scale model Numerical simulation Strain rate effect Dynamic increase factor
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Study on Multi-effect Time Parameters of Ergonomic Validity Index in Low-carbon Residential Kitchen
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作者 Jun Ji Hong Jin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第5期52-58,共7页
In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts... In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts of human factors on quantitative study,it proposes a method of building a parameter of ergonomic validity—multi-effect time by using cardiotachometer to record heart rate change,being used to evaluate the functional low-carbon ergonomic validity targeting at the ontological characteristics of kitchen. This method is used to determine the physical consumption intensity( multi-effect) through heart rate incremental relation based on the principles of physiology and ergonomics,and to confirm the ergonomic validity of environmental factors by the time to complete standard work as well as multi-effect quantitative analysis. The test results show that,under the kitchen operating conditions,the multi-effect( ME) can properly reflect the real-time status of the operator and is easily operated; the parameters obtained are not significantly related to the physiological status of the operator,and multi-effect time( MT) is sensitive to the physical consumption brought about to the operator due to kitchen environmental factors; thus,it can be taken as an objective index,which is simple and easy to operate in residential kitchen functional low-carbon evaluation. 展开更多
关键词 functional low-carbon human factors ergonomic validity index basal heart rate increment ratio multi-effect time of kitchen work
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An assessment of Charter airline benefits for Port Elizabeth and the Eastern Cape
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作者 Radu Mihailescu 《Chinese Business Review》 2010年第2期34-45,共12页
关键词 成本效益分析 航空公司 伊丽莎白 飞机租赁 世界杯足球赛 经济利益 组成部分 经济发展
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基于F-J-M法的桥梁温度与地震作用效应组合研究
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作者 王力 潘启仁 +2 位作者 周晓夫 杨喜娟 唐智勇 《防灾减灾工程学报》 CSCD 北大核心 2024年第2期273-282,共10页
目前铁路桥梁设计逐渐由容许应力法向极限状态法转变,而《铁路桥涵设计规范(极限状态法)》(Q/CR 9300—2018)并未提及地震作用与温度等可变作用的联合作用,给高寒高烈度区桥梁结构抗震设计带来了较大困难。为了推进桥梁以更经济的抗力... 目前铁路桥梁设计逐渐由容许应力法向极限状态法转变,而《铁路桥涵设计规范(极限状态法)》(Q/CR 9300—2018)并未提及地震作用与温度等可变作用的联合作用,给高寒高烈度区桥梁结构抗震设计带来了较大困难。为了推进桥梁以更经济的抗力方式抵御外荷载作用,通过目标可靠度指标确定其最优地震设计状况荷载组合分项系数,从而对现行桥梁设计规范抗震设计进行优化。建立了高寒地区某桥温度作用效应概率模型,使用Ferry Borges荷载组合理论探究地震和环境温度作用的效应分布特征,并基于JC法和多灾害荷载系数设计法(MH-LRFD)建立地震、温度作用荷载系数的表达式。依托某桥梁工程实例分别探究了地震、温度以及两者共同作用下的桥梁的失效概率。研究结果表明:环境温度引起的桥梁温度内力响应、主要构件材料特性变异均能显著影响桥梁的失效概率;对于高寒大温差地区,现行规范忽略环境温度效应将显著低估桥梁在地震作用下的失效概率。本文提出的F-J-M(Ferry Borges+JC+MH-LRFD)方法计算地震、温度作用组合系数,可为高寒地区桥梁抗震设计提供必要理论依据。 展开更多
关键词 温度效应概率模型 失效概率 Ferry Bordge法 MH-LRFD 荷载系数
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磁电弹性材料含正六边形纳米缺陷的表面效应研究
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作者 徐燕 杨娟 《力学季刊》 CAS CSCD 北大核心 2024年第2期519-530,共12页
在磁电弹性材料断裂力学框架下,利用表面弹性理论和解析函数边值理论,解析研究了反平面机械载荷、面内电载荷和磁载荷耦合作用下磁电弹性体中正六边形孔边均布六条等长裂纹的Ⅲ型断裂力学问题,确定了考虑表面效应时纳米尺寸裂纹问题的... 在磁电弹性材料断裂力学框架下,利用表面弹性理论和解析函数边值理论,解析研究了反平面机械载荷、面内电载荷和磁载荷耦合作用下磁电弹性体中正六边形孔边均布六条等长裂纹的Ⅲ型断裂力学问题,确定了考虑表面效应时纳米尺寸裂纹问题的精确解.基于以上解析解,通过数值算例揭示了表面效应、缺陷几何参数及所施加的损坏载荷分别在两种理想裂纹面电磁条件假设下对断裂参数的影响规律.研究发现:考虑表面效应时影响裂纹扩展的因素与经典弹性理论解答明显不同.各个物理分量呈现出显著的尺寸依赖效应,但随着缺陷尺寸的增加,表面效应的影响呈下降趋势,并趋于经典弹性理论值.研究可为该材料应用于微纳米结构和微机电系统提供理论指导. 展开更多
关键词 磁电弹性材料 纳米尺度 表面效应 场强度因子 能量释放率
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托伐普坦片联合托拉塞米片治疗对老年心力衰竭患者心功能的影响分析
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作者 丁伟红 《中外医疗》 2024年第15期107-110,共4页
目的 探讨托伐普坦片与托拉塞米片联合治疗对老年心力衰竭患者心功能的影响。方法 方便选取厦门市中医院于2021年9月—2023年11月收治96例老年心力衰竭患者作为研究对象,采取随机数表法分为两组,各48例。对照组患者接受托拉塞米片治疗,... 目的 探讨托伐普坦片与托拉塞米片联合治疗对老年心力衰竭患者心功能的影响。方法 方便选取厦门市中医院于2021年9月—2023年11月收治96例老年心力衰竭患者作为研究对象,采取随机数表法分为两组,各48例。对照组患者接受托拉塞米片治疗,研究组予托伐普坦片联合托拉塞米片治疗,比较两组患者治疗前后的心功能指标、临床相关指标,治疗后的临床疗效及不良反应发生率。结果 治疗后,研究组患者心功能指标水平与临床相关指标均优于对照组,差异有统计学意义(P均<0.05);研究组患者的临床治疗总有效率为97.92%高于对照组的81.25%,差异有统计学意义(χ^(2)=7.144,P<0.05);研究组不良反应总发生率低于对照组,差异有统计学意义(P<0.05)。结论 托伐普坦片联合托拉塞米片治疗老年心力衰竭患者,其心功能和临床相关指标显著改善,且临床治疗效果显著,安全性较高。 展开更多
关键词 托伐普坦片 托拉塞米片 老年心力衰竭 心功能 脑钠肽 有效率
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扩心方治疗慢性心力衰竭临床观察 被引量:1
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作者 吴琼 王佑华 +6 位作者 李广浩 马梦娇 周茂琳 安世英 毛美娇 曹敏 周端 《辽宁中医杂志》 CAS 北大核心 2024年第1期106-109,共4页
目的观察扩心方对慢性心力衰竭(chronic heart failure,CHF)患者心衰症状、心脏功能、心室重构及炎症因子的影响。方法纳入120例CHF患者,随机分为规范化西药治疗组(对照组)和扩心方联合规范化西药组(观察组),两组各60例,治疗12周,观察... 目的观察扩心方对慢性心力衰竭(chronic heart failure,CHF)患者心衰症状、心脏功能、心室重构及炎症因子的影响。方法纳入120例CHF患者,随机分为规范化西药治疗组(对照组)和扩心方联合规范化西药组(观察组),两组各60例,治疗12周,观察两组患者治疗前后心衰症状及心功能改善情况、明尼苏达心力衰竭生活质量量表(MLHFQ)评分、六分钟步行试验(6MWT)、心超、血清脑钠肽(BNP)、白细胞介素-2(IL-2)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、转化生长因子-β(TGF-β)、血管内皮生长因子(VEGF)水平变化。结果①治疗后,对照组、观察组临床总有效率分别为56.7%、83.3%,观察组改善优于对照组(P<0.05)。②治疗后,观察组在MLHFQ评分、6MWT、BNP变化上改善均优于对照组(P<0.05)。③治疗后,观察组在左室舒张末期内径(LVEDD)、左室射血分数(LVEF)改善优于对照组(P<0.05),两组在左室收缩末期内径(LVESD),室间隔厚度(IVS)、左室后壁厚度(LVPWT)差异无统计学意义(P>0.05)。④治疗后,观察组在血清IL-6、TNF-α、TGF-β、VEGF水平低于对照组(P<0.05),血清IL-2水平两组差异无统计学意义(P>0.05)。结论扩心方可改善CHF患者临床症状,提高心功能,其机制可能与改善心室重构、抑制炎性细胞因子相关。 展开更多
关键词 慢性心力衰竭 扩心方 临床疗效 心室重构 炎症因子
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直流输电用特高压晶闸管大气中子失效率评估和损伤机理
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作者 彭超 周杨 +5 位作者 陈中圆 雷志锋 马腾 张战刚 张鸿 何玉娟 《原子能科学技术》 EI CSCD 北大核心 2024年第1期248-256,共9页
本文基于散裂中子源开展了直流输电用8.5 kV/5 kA晶闸管的加速辐照试验。试验证实了大气中子导致的晶闸管单粒子烧毁失效现象,同时基于加速辐照试验结果计算了大气中子导致的晶闸管失效率。晶闸管的反向偏置电压和结温是影响晶闸管器件... 本文基于散裂中子源开展了直流输电用8.5 kV/5 kA晶闸管的加速辐照试验。试验证实了大气中子导致的晶闸管单粒子烧毁失效现象,同时基于加速辐照试验结果计算了大气中子导致的晶闸管失效率。晶闸管的反向偏置电压和结温是影响晶闸管器件失效的关键因素。大气中子失效率随着反向偏置电压的增加呈指数增加。此外,失效率随温度的降低而增加。对应器件偏置在50%额定电压下的情况,5℃时的失效率较25℃时增加了近6倍。基于TCAD仿真进一步验证了辐照导致晶闸管失效的机理。仿真表明,单粒子烧毁失效与辐射粒子入射诱发的雪崩击穿效应直接相关。雪崩击穿效应与晶闸管反向偏置电压正相关,而与结温负相关,这与大气中子失效率随电压和结温的变化关系一致。 展开更多
关键词 晶闸管 单粒子效应 大气中子 失效率
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碳纤维复合材料层合板的动态力学性能及失效机制
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作者 林作泓 高玉波 卢涛 《中北大学学报(自然科学版)》 CAS 2024年第4期550-556,共7页
为了进一步明确碳纤维增强复合材料(CFRP)在冲击加载下的动态力学行为,采用电子万能试验机和霍普金森压杆(SHPB)试验装置,研究了铺层方式为[-45°/90°/45°/0°]的CFRP在厚度和面内方向的静/动态力学性能。结果表明,C... 为了进一步明确碳纤维增强复合材料(CFRP)在冲击加载下的动态力学行为,采用电子万能试验机和霍普金森压杆(SHPB)试验装置,研究了铺层方式为[-45°/90°/45°/0°]的CFRP在厚度和面内方向的静/动态力学性能。结果表明,CFRP复合材料主要发生脆性破坏,在不同方向纤维铺层之间相互纠缠,有效支撑基体,可避免材料发生瞬间坍塌失效。受微裂纹扩展和加载速率关系的影响,复合材料呈现出明显的正相关应变率效应,虽然加入了不同铺层纤维,但材料失效破坏仍主要由基体决定。沿厚度方向加载,裂纹主要以沿45°角扩展的剪切破坏为主,断面在剪应力作用下出现了大量纤维的拔出和断裂。沿面内加载方向,纤维间的粘结层发生脆性断裂,与加载方向一致的纤维发生了屈曲失稳,裂纹穿透纤维层导致脱层。 展开更多
关键词 碳纤维增强复合材料层合板 力学性能 失效机理 应变率效应
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基于失效模式与效应分析的闭环管理在住院患者结肠镜检查肠道准备中的应用
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作者 申明 张铭光 +1 位作者 任宏飞 刘素珍 《中国医药导报》 CAS 2024年第17期103-105,112,共4页
目的 探究基于失效模式与效应分析(FMEA)的闭环管理对行结肠镜检查的住院患者的影响。方法 选取四川大学华西医院2022年7月至2023年8月收治的行结肠镜检查的住院患者156例,根据随机数字表法将其分为观察组和对照组,每组78例。对照组实... 目的 探究基于失效模式与效应分析(FMEA)的闭环管理对行结肠镜检查的住院患者的影响。方法 选取四川大学华西医院2022年7月至2023年8月收治的行结肠镜检查的住院患者156例,根据随机数字表法将其分为观察组和对照组,每组78例。对照组实施常规管理,观察组实施基于FMEA的闭环管理。比较两组肠道准备合格率、结肠镜检查时间、镜检舒适度(疼痛状态、镇静效果评分)。比较两组入院时及检查前结肠镜检查认知水平评分和不良反应总发生率。结果 观察组肠道准备合格率高于对照组,差异有统计学意义(P<0.05)。观察组结肠镜进镜时间、整体检查时间短于对照组,差异有统计学意义(P<0.05)。观察组疼痛状态、镇静效果评分低于对照组,差异有统计学意义(P<0.05)。入院时,两组肠镜检查认知水平评分比较,差异无统计学意义(P>0.05);检查前,两组结肠镜检查认知水平评分高于入院时,且观察组高于对照组,差异有统计学意义(P<0.05)。观察组不良反应总发生率低于对照组,差异有统计学意义(P<0.05)。结论 基于FMEA的闭环管理能显著提高住院患者肠道准备合格率,且能够缩短检查时间,提高患者舒适度。 展开更多
关键词 结肠镜检查 肠道准备 失效模式与效应分析 闭环管理 肠道准备合格率
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SGLT2抑制剂联合新活素治疗高血压伴心力衰竭的疗效及对患者TLR4/NF-κB信号通路指标的影响 被引量:1
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作者 彭娜娜 王小雅 +1 位作者 贾启华 张金生 《海南医学》 CAS 2024年第6期761-766,共6页
目的研究钠-葡萄糖协同转运蛋白2(SGLT2)抑制剂(达格列净)联合新活素治疗高血压伴心力衰竭(心衰)的临床效果及对患者外周血单核细胞Toll样受体4/核转录因子-κB(TLR4/NF-κB)信号通路指标的影响。方法前瞻性选取2021年5月至2023年6月郑... 目的研究钠-葡萄糖协同转运蛋白2(SGLT2)抑制剂(达格列净)联合新活素治疗高血压伴心力衰竭(心衰)的临床效果及对患者外周血单核细胞Toll样受体4/核转录因子-κB(TLR4/NF-κB)信号通路指标的影响。方法前瞻性选取2021年5月至2023年6月郑州大学第一附属医院收治的138例高血压伴心衰患者作为研究对象,采用随机数表法分为对照组、单一组和联合组各46例。对照组接受常规基础治疗,单一组在此基础上接受新活素治疗,联合组在此基础上接受达格列净联合新活素治疗。治疗7 d后比较三组患者的临床疗效,以及治疗前后的心功能[左室收缩末期内径(LVESD)、左室射血分数(LVEF)、心率(HR)]、运动耐力[6 min步行试验距离(6 MWT)]、血压[收缩压(SBP)、舒张压(DBP)]、氧化应激指标[丙二醛(MDA)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)]和TLR4/NF-κB信号通路相关指标[TLR4、NF-κB、白细胞介素-1β(IL-1β)、IL-6、肿瘤坏死因子-α(TNF-α)],同时比较三组患者的不良反应发生情况。结果联合组患者的治疗总有效率为95.65%,明显高于单一组的86.96%和对照组的73.91%,差异均有统计学意义(P<0.05);治疗后,联合组患者的LVEF、6 MWT分别为(43.28±3.16)%、(336.48±32.49)m,明显高于单一组的(40.54±2.68)%、(306.45±40.26)m和对照组的(38.07±2.89)%、(280.69±36.98)m,LVESD、HR分别为(35.29±4.26)mm、(71.34±3.62)次/min,明显低于单一组的(38.75±3.64)mm、(74.25±3.59)次/min和对照组的(42.36±4.05)mm、(76.46±3.98)次/min,且单一组变化幅度大于对照组,差异均有统计学意义(P<0.05);治疗后,联合组患者的SBP、DBP分别为(110.36±5.02)mmHg、(81.42±2.56)mmHg,明显低于单一组的(114.83±4.76)mmHg、(84.39±2.88)mmHg和对照组的(117.25±5.18)mmHg、(86.05±2.62)mmHg,且单一组低于对照组,差异均有统计学意义(P<0.05);治疗后,联合组患者的GSH-Px、CAT分别为(105.24±20.29)U/g·Hb、(148.35±32.46)U/mL,明显高于单一组的(90.35±19.45)U/g·Hb、(125.64±26.49)U/mL和对照组的(84.49±17.32)U/g·Hb、(103.29±25.38)U/mL,MDA为(7.39±2.56)mmol/L,明显低于单一组的(11.35±2.95)mmol/L和对照组的(13.08±2.72)mmol/L,且单一组变化幅度大于对照组,差异均有统计学意义(P<0.05);治疗后,联合组患者的TLR4 mRNA、NF-κB mRNA、IL-1βmRNA、IL-6 mRNA、TNF-αmRNA明显低于单一组和对照组,且单一组低于对照组,差异均有统计学意义(P<0.05);三组患者的不良反应总发生率比较差异无统计学意义(P>0.05)。结论SGLT2抑制剂联合新活素治疗高血压伴心衰能有效改善患者的氧化应激水平,调节TLR4/NF-κB信号通路,恢复患者血压与心功能,临床应用效果显著,且安全性较高。 展开更多
关键词 高血压伴心力衰竭 新活素 达格列净 氧化应激 外周血单核细胞Toll样受体4/核转录因子-κB信号通路 临床效果
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