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71.
目的 探讨不同剂量多巴酚丁胺对脓毒症休克兔急性肺损伤(acute lung injury,ALI)的保护作用及其可能机制.方法 采用盲肠结扎穿孔联合静脉注射内毒素制备脓毒症休克模型,将70只新西兰雄性大白兔随机(随机数字法)均分为假手术组(A组)、ALI模型组(B组)、多巴酚丁胺低剂量组(C组)、多巴酚丁胺中剂量组(D组)和多巴酚丁胺高剂量组(E组),分别于造模后3h和6h点处死,留取肺组织标本.ELISA法检测环磷酸腺苷(cyclicadenosine monophosphate,cAMP)浓度;Western-blot法检测水通道蛋白5(Aquaporin 5,AQP5)蛋白浓度;计算肺湿/干重(wet to dry weight,W/D)比值;光镜和电镜下观察各组小鼠肺组织病理学改变,并对肺组织病理损伤进行评分.多组间差异比较采用单因素方差分析,组间两两比较采用LSD法.结果 与A组相比,B组cAMP、AQP5蛋白浓度在3h及6h明显降低(3.53±0.43)pmol/mL vs.(21.18±0.62)pmol/mL; (0.44±0.04)pmol/mLvs.(0.99 ±0.06)pmol/mL;(2.71 ±0.56) pmol/mL vs.(21.78±0.62) pmol/mL; (0.29±0.05) pmol/mLvs.(0.91±0.06) pmol/mL;P<0.001,W/D比值则明显升高P<0.00.与B组相比,C组cAMP及AQP5蛋白水平在6h明显增加(8.48±0.61) pmol/mLvs.(2.71 ±0.56) pmol/mL,P<0.001; (0.49 ±0.04)pmol/mLvs.(0.29±0.05) pmol/mL,(P=0.001),D、E组cAMP及AQP5蛋白水平在3h、6h明显增加(10.86±0.66) pmol/mLvs.(3.53±0.43) pmol/mL;(0.60 ±0.05) pmol/mLvs.(0.44±0.04) pmol/mL; (13.80 ±0.49) pmol/mLvs.(2.71 ±0.56) pmol/mL; (0.64 ±0.03) pmol/mLvs.(0.29±0.05) pmol/mL; (15.57 ±0.60) pmol/mLvs.(3.53±0.43) pmol/mL; (0.91 ±0.05)pmol/mLvs.(0.44±0.04)pmol/mL; (19.30±0.42)pmol/mLvs.(2.71±0.56)pmol/mL;(0.89±0.08) pmol/mLvs.(0.29±0.05)pmol/mL;P<0.01,E组W/D比值明显降低(P=0.002;P=0.001).与C、D组相比,E组cAMP及AQP5水平在3h、6h均有所增加(P<0.01).光镜及电镜下,B组肺的病理形态及超微结构损伤均较重,肺病理学评分明显升高(P<0.01);多巴酚丁胺干预后,肺的病理形态及超微结构损伤有所减轻,肺组织病理学评分明显降低(P<0.01).结论 多巴酚丁胺对内毒素诱导的急性肺损伤有一定程度保护作用,其机制可能与提高肺组织cAMP水平,上调AQP5蛋白表达量有关,且大剂量多巴酚丁胺效果更佳. 相似文献
72.
目的 探讨速度向量成像结合多巴酚丁胺负荷试验在左室射血分数(LVEF)值正常的糖尿病患者左室长轴心肌应变功能评价中的价值.方法 30例排除冠心病、瓣膜性心脏病、高血压、先天性心脏病,并且经常规的超声心动图检查LVEF值>50%的糖尿病患者,另选20例性别、年龄相匹配的健康志愿者作为对照,分别在静息状态、各级多巴酚丁胺负荷状态存储心尖四腔观、两腔观及左室长轴观的动态二维图像.用Sygno VVI软件进行脱机分析,获得左室各节段的长轴最大收缩速度(Vs)、应变(ε)、应变率(SR).结果 对照组和糖尿病组组内比较,左室各壁Vs、e、SR自基底段至心尖段均呈递减趋势,且差异均具有统计学意义.对照组和糖尿病组组间各相应节段(18节段)配对比较,静息状态下,糖尿病组7个节段的SR、4个节段的ε、3个节段的Vs较对照组显著减低(P<0.05);多巴酚丁胺最大负荷后,糖尿病组各指标均较对照组显著减低(P<0.05).其中,静息状态下,糖尿病组心尖段67%的指标低于对照组,而中间段11%的指标低于对照组,基底段各参数与对照组无明显差异.结论 左室长轴的Vs、ε、SR从基底段向心尖段逐渐减弱;糖尿病患者早期长轴心肌Vs、e、SR减退最早表现在心尖段的心肌组织;多巴酚丁胺负荷能提高VVI各参数检出心肌收缩功能障碍的敏感性. 相似文献
73.
AIMS: This study investigated the functional outcome of wall-thinned,akinetic myocardium after revascularization and evaluated theaccuracy of dobutamine echocardiography in predicting post-revascularizationfunctional recovery with the assessment of end-diastolic wallthickness in chronic ischaemic patients. METHODS AND RESULTS: Fifty-three patients underwent dobutamine echocardiography beforecoronary revascularization. End-diastolic wall thickness wasalso evaluated before and after revascularization. The sensitivityand specificity of dobutamine echocardiography to predict post-revascularizationfunctional recovery were 69% and 100% in 58 akinetic/dyskineticsegments, and 86% and 57% in 96 hypokinetic segments. Of 19akinetic/dyskinetic segments with a preserved end-diastolicwall thickness, 17 (89%) showed functional recovery after revascularization,and dobutamine detected 14 (83%) of these 17 segments. Of 39akinetic/dyskinetic segments with a thinned end-diastolic wallthickness, 15 (38%) achieved functional recovery, whereas dobutamineechocardiography detected recovery in only eight (53%). Further,of these 15 viable, wall-thinned segments, 12 (80%) showed anincreased end-diastolic wall thickness after revascularization(mean±SD were from 5·6±0·7 mm atbaseline to 7·4±1·3 mm and 9·7±1mm after 1 week and after 3 months, respectively), and only5 (42%) of these responded to dobutamine. CONCLUSION: Dobutamine echocardiography showed a lessened sensitivity topredict post-revascularization functional recovery in akinetic/dyskineticsegments with a thinned end-diastolic wall thickness that subsequentlyincreased in size. 相似文献
74.
75.
Avgeropoulou C Andreadou I Markantonis-Kyroudis S Demopoulou M Missovoulos P Androulakis A Kallikazaros I 《European journal of heart failure》2005,7(5):882-887
AIM: To investigate the effect of a new inotropic drug, levosimendan compared with dobutamine on levels of brain natriuretic peptide (BNP), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-alpha), and malondialdehyde (MDA) in patients with severe decompensated heart failure. METHODS AND RESULTS: Twenty-nine consecutive patients (22 males and 7 females), mean age 70.5+/-9.9 years, with decompensated heart failure on standard medical therapy, were randomised to receive either a 24 h infusion of levosimendan (n=15) or dobutamine (n=14). Blood samples were drawn at baseline, 48 h and 5 days post infusion. Levosimendan produced a significant reduction in BNP compared to baseline, at both 48 h (744.1+/-100 vs 1136.3+/-93.7 pg/ml, p=0.04) and 5 days (446+/-119.3 vs 1136.3+/-93.7 pg/ml, p=0.03), while IL-6 values decreased after 5 days (4.8+/-1.3 vs 8.6+/-1.5 pg/ml, p=0.01). MDA levels were significantly lower 5 days after levosimendan compared to baseline (2.3+/-0.2 vs 3+/-0.3 microM, p=0.01). TNF-alpha levels did not differ between the groups. The comparison of percentage alteration compared to baseline showed that BNP (-44.5+/-7.6% vs 4.8+/-18.7%, p=0.025), MDA (-21.8+/-5.1% vs 14.9+/-8.5%, p=0.001) and IL-6 (-38.8+/-12.5% vs 70.2+/-24%, p=0.001) levels were significantly lower in the levosimendan group 5 days after treatment compared to the dobutamine group. CONCLUSIONS: Treatment with levosimendan in advanced decompensated heart failure exerts a beneficial hemodynamic, anti-inflammatory and antioxidant effect. These findings may give an insight into the favourable impact on mortality that levosimendan appears to have in published multicenter trials. 相似文献
76.
药物负荷超声心动图与双核素心肌显像对比检测存活心肌 总被引:9,自引:1,他引:9
Yang YJ Yang WX Shi RF Hu FH You SJ Tian YQ He ZX Wang YW Ye L Chen JL Gao RL Chen ZJ 《中华心血管病杂志》2005,33(4):323-327
目的 比较99mTc 甲氧基异丁腈(MIBI) /18F 脱氧葡萄糖(FDG)双核素同时采集法(DISA)单光子发射型断层显像(SPECT)和药物负荷二维超声心动图(2DE)试验,识别冠心病左心室收缩功能严重减低患者[左室射血分数(LVEF)≤45% ]存活心肌的准确性。方法 陈旧性心肌梗死患者26例,平均LVEF(38. 6±4 .9 )%,在一周内分别进行小剂量多巴酚丁胺10μg·kg-1·min-1(Dob10μg)、亚硝酸异山梨酯合用Dob5μg·kg-1·min-1 (ISDN Dob5μg)的2DE试验,以及DISASPECT心肌显像。所有患者在冠状动脉血管重建(CRV)术后(6 .8±2 .9)个月完成了2DE复查。采用16节段半定量法分别分析图像,以CRV术后收缩功能改善节段为存活标准,比较两种方法检测存活心肌的敏感性、特异性和准确性。结果 26例患者272个运动异常节段中,术后156个( 57. 4% )有收缩运动改善。DISASPECT检测出72 .4% (134 /254)存活心肌节段,显著高于术后实际改善率(P<0 .001)。Dob10μg2DE的存活心肌检出率为65 5% (163 /249 ),ISDN Dob5μg2DE的为65 .7%(176 /268),均与术后实际改善率一致(P均>0 .05)。DISASPECT检测存活心肌的敏感性、特异性和准确性分别为93%, 55%和76. 8%;Dob10μg2DE的分别为88 .6%, 64 .2%和77. 9%,两种方法检测效果相当(P均>0 .05)。ISDN Dob5μg 相似文献
77.
78.
目的 应用速度向量成像结合多巴酚丁胺负荷试验评价射血分数(EF)正常的糖尿病 DM)患者左室短轴收缩功能.方法 30例排除冠心病、高血压、瓣膜性心脏病、先天性心脏病,并且经常规的超声心动图检查EF值>50%的DM患者,另选20例性别、年龄相匹配的健康志愿者作为对照,分别在静息状态、多巴酚丁胺负荷(10、20、30、40μg·kg-1·min 1)状态存储胸骨旁左室短轴基底段、中间段及心尖段动态二维图像.应用Sygno VVI软件进行脱机分析,获得各个节段的心肌最大收缩速度 Vs)、应变 ε)、应变率 SR).结果 对照组和DM组组内比较,自基底段至心尖段Vs、ε、SR均呈递减趋势.对照组和DM组间比较,静息状态下,DM组心尖段SR较对照组显著减低 P<0.05),其余各指标与对照组的差异均无统计学意义;10 μg·kg-1·min-1多巴酚丁胺负荷后,DM组中间段和心尖段的SR均较对照组显著减低 P<0.05);心尖段的Vs和ε亦较对照组显著减低(P<0.05);20μg·kg-1·min-多巴酚丁胺负荷后,DM组基底段、中间段和心尖段的SR均较对照组显著减低(P<0.05);中间段和心尖段的Vs和ε亦较对照组显著减低(P<0.05).多巴酚丁胺最大负荷后,DM组各指标均较对照组显著减低(P<0.05).结论 DM患者早期收缩功能的减退最早表现在心尖段的心肌组织;SR比Vs、ε更为敏感;多巴酚丁胺负荷试验与速度向量成像相结合,可以明显增加各指标检出糖尿病心肌收缩功能障碍的敏感性. 相似文献
79.
Denis Pellerin Alain Berdeaux Laurent Cohen Jean-François Giudicelli Serge Witchitz Colette Veyrat 《Ultrasound in medicine & biology》1998,24(9):1271-1283
Duration of the pre-ejection period is a sensitive index of myocardial function. Our purpose was to document normal pre-ejectional left ventricular (LV) wall motions at rest and under dobutamine using Doppler myocardial imaging (DMI), and to correlate posterior wall velocities with indices of LV systolic function. M-mode recordings of both walls were imaged on eight conscious dogs chronically instrumented. Subendocardial pre-ejectional velocities were digitized and measured every 3.8 ms. DMI analysis consisted of sign recognition, velocity measurement, duration and timing from the Q wave of the electrocardiogram. Isovolumic contraction time (Ict) was represented by the time interval from onset to peak of the first derivative of LV pressure. Conventional Doppler labelling of velocity signs, positive toward and negative away from the transducer, was applied to the direction of encoded wall motions. For physiological understanding, wall motions of both walls were also labelled inward and outward with respect to the left ventricular cavity center. In each wall, PEP was shown as several colored strips, each strip representing the period of time that the wall was moving in one direction. Changes in velocity sign corresponding to changes in direction of motion were opposed in each wall (p < 0.001), featuring successive inward and outward wall motions. There was a markedly sustained inward motion during Ict. Its velocity amplitude increased with dobutamine. There was a positive correlation between velocities of the inward motion contemporaneous of Ict and ejection fraction (r = 0.72, p < 0.003). Values of Ict respectively drawn from DMI and from hemodynamics were also significantly correlated (r = 0.85, p < 0.007). Thus, the inward motion evidenced by DMI during Ict appears promising to assess myocardial function and effect of drugs. 相似文献
80.
目的:评价小剂量多巴酚丁胺超声心动图负荷试验(DSE)和放射性核素心肌灌注显像(SPECT)预测心肌存活性的价值。方法:以15例成功的PCI患者术后6个月室壁运动改善为检验标准,进行小剂量多巴酚丁胺超声心动图负荷试验及SPECT检查,比较两者检测心肌存活性的准确性。结果:DSE峰剂量期与低剂量期在预测心肌存活敏感性、阴性预测准确性方面差异具有统计学意义;与DSE相比,SPECT具有较高的敏感性但其特异性较低。结论:在预测心肌存活性的价值方面,DSE和SPECT各有优缺点,但DSE更具实用性。 相似文献