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31.
随着细胞组织工程学的发展,骨形态发生蛋白(bone morphogenetic protein,BMP)越来越多的应用在骨科领域,而骨形态发生蛋白-2(bone morphogenetic protein,BMP-2)在治疗骨缺损,骨不愈合等方面的效果已经在基础实验和临床实践上均得到了证实[1-3],其作用机制可能是BMP-2可诱导间充质干细胞向软骨方向分化,并通过Smad通路及MAPK通路传导,并对骨组织的形成、生长和损伤的修复具有促进作用[4]。基于这一作用机制,越来越多的学者把研究重点放在治疗股骨头坏死领域,文章就近年来BMP-2治疗股骨头坏死研究进展。  相似文献   
32.

Aim:

The aim of study was to: 1) examine the relationship between ABO blood groups and extent of coronary atherosclerosis in patients with chronic coronary artery disease (CAD), 2) compare ABO blood groups distribution in CAD patients and general population, 3) examine possible differences in traditional risk factors frequency in CAD patients with different ABO blood groups.

Materials and methods:

In the 646 chronic CAD patients (72.4% males) coronary angiograms were scored by quantitative assessment using multiple angiographic scoring system, Traditional risk factors were self reported or measured by standard methods. ABO blood distribution of patients was compared with group of 651 healthy blood donors (74.6% males).

Results:

Among all ABO blood group patients there was no significant difference between the extent of coronary atherosclerosis with regard to all the three scoring systems: number of affected coronary arteries (P = 0.857), Gensini score (P = 0.818), and number of segments narrowed > 50% (P = 0.781). There was no significant difference in ABO blood group distribution between CAD patients and healthy blood donors. Among CAD patients, men with blood group AB were significantly younger than their pairs with non-AB blood groups (P = 0.008). Among CAD patients with AB blood group, males < 50 yrs were significantly overrepresented when compared with the non-AB groups (P = 0.003).

Conclusions:

No association between ABO blood groups and the extent of coronary atherosclerosis in Croatian CAD patients is observed. Observation that AB blood group might possibly identify Croatian males at risk to develop the premature CAD has to be tested in larger cohort of patients.  相似文献   
33.
传统教学模式以教师课堂讲授为主,无法激发学生探究知识的热情,难以取得令人满意的教学效果。“行动学习法”是克服传统教学模式弊端的重要方式,是现代教学方法改革的新趋势。将以“行动学习法”为中心的教学模式应用到股骨头坏死临床实践教学中,可以激发规培生对骨科的兴趣,提高他们在骨科规培时的实践能力。  相似文献   
34.
The dysfunction of coronary microcirculation is an important cause of coronary artery disease (CAD). The index of microcirculatory resistance (IMR) is a quantitative evaluation of coronary microcirculatory function, which provides a significant reference for the prediction, diagnosis, treatment, and prognosis of CAD. IMR also plays a key role in investigating the interaction between epicardial and microcirculatory dysfunctions, and is closely associated with coronary hemodynamic parameters such as flow rate, distal coronary pressure, and aortic pressure, which have been widely applied in computational studies of CAD. However, there is currently a lack of consensus across studies on the normal and pathological ranges of IMR. The relationships between IMR and coronary hemodynamic parameters have not been accurately quantified, which limits the application of IMR in computational CAD studies. In this paper, we discuss the research gaps between IMR and its potential applications in the computational simulation of CAD. Computational simulation based on the combination of IMR and other hemodynamic parameters is a promising technology to improve the diagnosis and guide clinical trials of CAD.  相似文献   
35.
ABSTRACT

Current evidence suggests that chronic inflammation contributes to the development of coronary artery disease (CAD). Interestingly, exercise may constitute a method of reducing inflammation in this patient population. As such, this systematic review and meta-analysis examined the evidence generated by randomised studies that investigated the effect of exercise on inflammatory biomarkers in CAD. Literature was sought from various sources. Outcomes were pooled in a random-effects model to calculate standardised mean differences (SMD) with 95% confidence intervals (CI). Twenty-five studies were reviewed; post-intervention C-reactive protein (SMD: ?0.55 (95% CI: ?0.93, ?0.16), P = 0.005), fibrinogen (SMD: ?0.52 (95% CI: ?0.74, ?0.29, P = <0.00001)), and von Willebrand factor (SMD: ?1.57 (95% CI: ?2.23, ?0.92), P = <0.00001) values were significantly lower in exercise groups compared to controls. In addition, qualitative analyses identified evidence that supports a beneficial effect of exercise on these acute-phase reactants. However, the impact of exercise on anti–inflammatory cytokines, adhesion molecules, and chemokines is equivocal, which may be attributed to a paucity of research. Nevertheless, the findings of this review suggest that exercise induces an anti–inflammatory effect in CAD patients. Although, the quality of evidence needs to be improved by further randomised studies with high methodological qualities and large sample sizes.  相似文献   
36.
摘要:目的:探讨褪黑素(melatonin, MT)在有氧运动改善自发性高血压大鼠(SHR)肠系膜动脉功能中的作用及可能的外周血管机制。方法:选用雄性SHR 16只,随机分为高血压安静组(SHR-SED)和高血压运动组(SHR-EX),后者进行8周有氧跑台运动。另选用同龄雄性WKY大鼠8只作为正常血压对照组。8周后,取肠系膜动脉,采用离体微血管环实验测定二级肠系膜动脉的舒缩特性、western blot和免疫荧光共染法检测肠系膜动脉的褪黑素受体MT1、MT2和eNOS蛋白的表达和分布。结果:1)SHR-SED组基础收缩压(SBP)显著高于WKY组,经过有氧运动训练后SBP显著下降;2)有氧运动可增加肠系膜动脉对乙酰胆碱(ACh)的舒张反应,其pIC50值为WKY>SHR-EX>SHR-SED; MT (10?4 mol/L)预孵育微血管环20 min,可明显增加ACh(10-9~10-5 mol/L)的舒张反应,但对外源一氧化氮供体硝普钠(SNP,10-9~10-5 mol/L)诱发的舒张反应无明显效果; 且MT1/MT2非选择性拮抗剂luzindole(2×10?6 mol/L)预孵育微血管环20 min,可阻断MT对ACh舒张反应的加强效果;3)SHR-EX组MT1、MT2和eNOS表达均显著高于SHE-SED组,有氧运动显著抑制MT1、MT2和eNOS表达的下调;4)免疫荧光共定位检测MT2蛋白位于整个肠系膜动脉内,包括细胞外膜、血管平滑肌细胞层和内皮细胞层,eNOS蛋白主要存在于肠系膜动脉的内皮细胞层,MT2和eNOS蛋白二者共定位于肠系膜动脉的内皮细胞层。结论:长期有氧运动可有效降低SHR的基础血压,增强肠系膜动脉血管舒张作用,其中褪黑素是其重要机制之一。褪黑素可能是通过血管褪黑素受体及内皮途径起作用。  相似文献   
37.
不同强度运动对大鼠冠状动脉CGRP、ET- 1 和NOS 表达的影响   总被引:1,自引:0,他引:1  
目的:探讨运动对大鼠冠状动脉降钙素基因相关肽(CGRP)、内皮素(ET-1)和一氧化氮合酶(NOS)表达的影响.方法:健康雄性SD3月龄大鼠24只,分为安静对照组、小强度运动组和大强度运动组,运动组采用大鼠跑台运动方式,建立大鼠不同强度运动模型,运用免疫组织化学SABC法研究不同强度运动对大鼠冠状动脉CGRP、ET-1、神经型一氧化氮合酶(nNOS)、诱导型一氧化氮合酶(iNOS)和内皮型一氧化氮合酶(eNOS)表达的影响.结果:与安静对照组比较,小强度运动组和大强度运动组CGRP、nNOS、iNOS和eNOS均显著性升高,小强度运动组ET-1显著降低,大强度运动组ET-1显著性升高.与小强度运动组比较,大强度运动组CGRP、ET-1、nNOS、iNOS和eNOS的表达变化均有显著性差异.小强度运动组和大强度运动组ET-1/CGRP和ET-1/NOS比值均低于安静对照组.结论:运动可引起大鼠冠状动脉CGRP、ET-1及NOS的表达变化,且与运动强度关系密切.因此认为,不同强度运动引起ET-1/CGRP和ET-1/NOS比值的变化可能是运动引起心血管生物功能改变的因素之一.  相似文献   
38.
举重、摔跤运动员心室及肺动脉内径的测定与分析   总被引:1,自引:0,他引:1  
为了进一步探讨以无氧供能为主的举重、摔跤运动对心血管系统的影响,实验测定分析了10名举重运动员、10名摔跤运动员和10名无训练者安静时左右心室舒张末内径及肺动脉内径。结果发现举重运动员的LVIDd、RVIDd和肺动脉内径与对照组比较,指数值增大并有显著性意义;摔跤运动员仅LVIDd较举重组和对照组有统计学意义,表明举重运动的缺氧程度比摔跤运动高,体现了专项特点。  相似文献   
39.
提出了基于侧抑制理论和细胞神经网络(CNN)的数字式非循环侧抑制网络,给出其用于数字图象联想记忆的算法,并给出了仿真结果。  相似文献   
40.
对蕉城区交通干道进行车流量和噪声的实地监测,结果表明,区内交通干交通干道平均等效A声级Leq=69.64dB(A),符合国家标准.分析城区交通噪声污染的原因,并对此提出了相关建议.  相似文献   
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