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131.
Summary The monocrofaline-induced structural changes of small pulmonary arteries in rat and their relationship with pulmonary hypertension
and right ventricular hypertrophy were observed by determining the right ventricular systolic pressure, and by light and electron
microscope and morphometry. One to 38 days after last injection of monocrotaline (MCT), a medial thickening and lumen marrrowing
of the circular muscular arteries (CMA), accompanying terminal (TB) and respiratory bronchioles (RB), were found. And there
after the lumen of CMA, accompanying TB, became dilated, and its medial thickness (MT) decreased, whereas the histopathologic
changes of the partially muscular arteries (PMA), accompanying RB, became severe, their MT increased continuously, and finally
reached the peak value on Day 50. At the first day after last MCT treatment, inflammation and muscularization were found in
PMA and nonmuscular arteries (NMA), and became more severe with the cause of disease. Therefore, the intra-acinar pulmonary
arteries, both CMA and PMA, increased in number while the NMA decreased in number significantly because of the structural
remodeling. Four days after MCT treatment, the right ventricular systolic pressure began to rise, and reached its peak value
on Day 50. Eight days after MCT injection, right ventricular hypertrophy developed, and became most significant from Day 23
to Day 30. The results suggest that structural remodeling, i.e. muscularization, of intra-acinar pulmonary arteries plays
an important role in the development of pulmonary hypertension and right ventricular hypertrophy. 相似文献
132.
非体外循环冠状动脉搭桥手术的麻醉方法及血液动力学和氧代谢的变化 总被引:18,自引:0,他引:18
目的 观察非体外循环冠状动脉搭桥手术的麻醉方法、术中病人血液动力学和氧代谢的变化以及术后病人的早期.非体外循环冠状动脉搭桥手术闰人20例,麻醉用咪唑安定0.1-0.2mg/kg、芬太尼15-30μg/kg及0.5%-2%的吸入麻醉药等,在切皮前、开心包后、心脏操作中、操作完成后10min及术毕观察血液动力学指标及脑氧饱和度,同时采集桡动脉和肺动脉血,测定血气及动脉血乳酸(ABL),计算氧供DO2)、氧耗(VO2)和氧摄取率(ERO2)。术后早期观察术后拔除气管插管、ICU停留及术后住院时间、并发症及死亡等情况。结果 心脏操作中MAP、SV、SI下降,HR、CVP升高,MAP下降以搭回旋支时最明显(P<0.01),HR升高以搭右冠时最明显(P<0.01);心脏操作中DO2降低(P<0.05),VO2无变化,ERO2升高(P<0.01);操作后DO2、ERO2恢复至操作前水平;操作后ABL升高(P<0.01)。结论 本组麻醉方法使病人完全度过非体外循环搭桥术,在心脏操作期易出现血压、每搏量、心指数下降,伴心率、静脉压升高,但时间短暂无严重后果,氧代谢紊乱及缺氧程度较轻。 相似文献
133.
目的 总结冠状动脉旁路移植术治疗冠心病的体会。 方法 回顾性分析 3 0 6例冠状动脉旁路移植术。男 2 49例 ,女 5 7例。应用体外循环 2 3 4例 ,非体外循环 72例。搭桥数 1~ 6支 人 ,平均 (3 .45± 1.2 5 )支 人。对手术方法、主要并发症和术后处理进行分析总结。结果 二次开胸 5例 (1.6% ) ,低心排综合征 10例 (3 .3 % ) ,应用IABP4例 (1.3 % ) ,肝功能不全 6例 (2 .0 % )。肾功能不全 7例 (2 .3 % ) ,反复发作房颤 2 3例 (7.5 % ) ,肺功能不全 6例(2 .0 % ) ,脑合并症 3例 (1.0 % ) ,胸腔积液 41例 (13 .4% )。死亡 7例 (2 .3 % ) ,其余病人康复出院。结论 合理的选择病人 ,成熟的手术技术 ,良好的心肌保护及术后处理的加强是提高冠状动脉旁路移植术疗效的重要措施。 相似文献
134.
目的 探讨冠心病患者与颈动脉粥样硬化之间的发生关系。方法 主要应用彩色多普勒超声技术检测 10 2例冠心病患者的颈动脉 ,对其中 34例进行冠状动脉造影检查。结果 为各组冠心病患者颈动脉管壁内 -中膜厚度 ,斑块指数均显著增高 ,其中心肌梗死患者伴有明显的血流参数异常 ,34例患者冠状动脉造影与颈动脉超声检查符合率为 75 % ,而且冠状动脉病变越重 ,颈动脉硬化发生率越高。结论 颈动脉粥样硬化程度可间接反映冠状动脉病变程度。 相似文献
135.
Petru Liuba Jerker Persson Jukka Luoma Seppo Yl?-Herttuala Erkki Pesonen 《European heart journal》2003,24(6):515-521
BACKGROUND: Atherosclerosis begins early in life. Infections might contribute to the pathogenesis of atherosclerosis. In this study, we investigated whether acute infections in children could alter the carotid wall morphology and the lipid profile. METHODS: Mean carotid intima-media thickness (IMT) was measured by high-resolution ultrasound in 28 hospitalised children (mean age: 5+/-2 years), who fulfilled the diagnostic criteria of acute infections (body temperature, >38 degrees C; C-reactive protein, >15mg/ml, and clinical), and in 20 age- and gender-matched controls. Antibodies against oxidised low-density lipoprotein (anti-oxLDL antibodies), as well as total and high-density lipoprotein cholesterol (HDL-C) were analysed in all children. The infection group was investigated both during the acute illness and 3 months after clinical recovery (post-infection). RESULTS: During the acute illness, the infection group had elevated anti-oxLDL antibodies and decreased HDL-C, as compared to those obtained at 3 months and in controls (p<0.05). These changes in the infection group were followed, at 3 months, by thickening of carotid intima-media. Those who received antibiotics during their acute illness had less carotid thickening than those who were not treated with antibiotics (p<0.05). CONCLUSION: Acute infections in children seem to be accompanied by enhanced oxidative modification of LDL and by decrease in HDL-C. These lipid changes may be followed by thickening of carotid artery intima-media. These findings suggest that, in childhood, acute infections could be associated with increased risk of atherosclerosis, and warrant further studies on this topic. 相似文献
136.
4 背景
强化降脂使低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C)低于指南推荐的水平将使急性冠脉综合征患者获益。但强化降脂使稳定性冠心病患者的LDL-C低于100mg/dL是否安全和有效尚不清楚。 相似文献
137.
颈动脉分叉血液动力状态的计算流体力学初步研究 总被引:3,自引:2,他引:1
目的应用计算流体力学(CFD)方法结合血管影像显示在体颈动脉分叉的血流动力状态.方法选取1例志愿者,采用Siemens多层螺旋CT机行左侧颈动脉CT血管成像检查(CTA),扫描所得原始图像经计算机后处理后,用CFD方法计算并显示血液动力学各项指标.结果(1)该血管血液流率均值范围为0.04~0.36 m/s,颈外和颈内动脉的内侧壁(均以分叉顶点为参照)可见一高血流速区,球部可见较大片低血流速区;颈动脉分叉及颈内、外动脉近端均可见血液涡流与回流.(2)血液绝对压、静态压和动态压的均值范围分别为100 266.70~101 615.90 Pa、-10 58.34~290.88 Pa、6.12~553.25 Pa;(3)管壁切应力均值范围为0.59~5.35 Pa,在颈动脉球部及颈内动脉后壁显示大范围的低切应力区,最低约为0.25 Pa,颈外动脉前外侧壁存在一小范围低切应力区.结论CFD方法结合血管影像能计算并显示在体颈动脉分叉的个体化血液动力学指标. 相似文献
138.
Haemodynamic studies in early stroke 总被引:2,自引:0,他引:2
Summary We investigated prospectively a consecutive series of 81 patients suffering from acute middle cerebral artery (MCA) ischaemia by transcranial Doppler ultrasonography (TCD) within 24 h of the onset of symptoms. To monitor the haemodynamic changes follow-up recordings were carried out at short intervals during the next 2–3 weeks until stable haemodynamic status was achieved. In order to estimate the value of early TCD examinations in predicting the extent of brain damage seen later on, initial MCA flow reduction was correlated with infarction size and pattern on computed tomography. Fifty-three cases showed sufficient ultrasound penetration through the temporal bone. MCA flow asymmetries were recorded in 45 patients (85%); occlusion was observed in 17. Recanalization occurred in 11 patients followed by transient hyperaemia in 3, leaving residual stenosis in 2. Initial increase of flow velocities normalized within days or weeks in 7 out of 9 patients, while 2 developed residual MCA stenosis. Nineteen patients showed a considerable flow reduction on admission, which returned to normal in 9; transient hyperaemia was detected in 5 of these. Eight patients did not show any MCA flow asymmetry. Our study revealed very variable haemodynamic changes in acute stroke, which influenced further diagnostic and therapeutic management. The high rate of spontaneous recanalizations of MCA occlusions followed by transient hyperaemia in many cases has an important bearing on thrombolytic or theological therapy. Flow velocity differences could be related to infarction pattern rather than to infarction volume. Early MCA flow asymmetry recorded by TCD within the first 24 h could not reliably predict the extent of persistent brain damage or clinical outcome. 相似文献
139.
采用血管灌注和透明切片,在立体解剖显微镜下对30例脑桥内部动脉的分群,经行分支和供应范围进行了观察。并应用图像分析系统测算了脑桥内部主要神经核团和纤维束的毛细血管密度。脑桥内部前正中群有三组长动脉,分别由脚间窝下端,基底沟中部和盲孔处穿入,这些动脉在向脑桥被盖部经行和分布的过程中,可形成多级直角分支,使之呈“垂柳状”外观。脑桥内部的毛细血管构筑,在透明切片上,可显示出神经结构的轮廓。其中上橄榄核的毛细血管密度最高,小脑上脚的毛细血管密度最低。 相似文献
140.
支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 总被引:1,自引:1,他引:0
目的 研究支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 (NSCLC)的可行性及临床价值。方法 76例NSCLC患者随机分成A、B 2组 ,A组先行 2次支气管动脉灌注化疗 (BAI) ,第 2次BAI 1~ 2周后再行直线加速器放射治疗 (RT) ;B组单纯行 2次BAI (对照组 )。结果 临床疗效 ,A组 (BAI RT)和B组 (BAI)分别为 89.47%和 60 .5 3% (Ρ <0 .0 1) ;1、3年生存率 ,A、B组分别为 81.5 8%、5 0 .0 0 %和 60 .5 3%、2 1.0 5 % ( 0 .0 1<Ρ <0 .0 5 )。结论 支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌的临床疗效和患者 1、3年生存率均显著提高 相似文献