• 【Grieshaber空气系统在维持气管导管袖带压力中的应用。】 复制标题 收藏 收藏
    DOI:10.1016/0952-8180(90)90050-d 复制DOI
    作者列表:Vitkun SA,Lagasse RS,Kyle KT,Poppers PJ
    BACKGROUND & AIMS: :The Grieshaber Air System was designed to maintain intraocular pressure during ophthalmologic surgery. It also has been used to maintain pressure in leaking endotracheal tube cuffs. It is a very useful device, especially if the intubation is difficult or the patient's position precludes replacement of the endotracheal tube. Two patients are presented in whom the system was used to maintain endotracheal tube cuff pressure.
    背景与目标: : Grieshaber空气系统旨在在眼科手术期间保持眼内压。它也已用于维持气管导管袖口泄漏的压力。这是一种非常有用的设备,尤其是在插管困难或患者的位置无法更换气管插管的情况下。介绍了两名患者,其中该系统用于维持气管导管袖带压力。
  • 【血液透析患者踝臂指数随时间的下降和心血管结局。】 复制标题 收藏 收藏
    DOI:10.1097/MAJ.0b013e31825141bf 复制DOI
    作者列表:Chen SC,Chang JM,Liu WC,Huang JC,Chen YY,Yang TK,Su HM,Chen HC
    BACKGROUND & AIMS: INTRODUCTION:Abnormal ankle-brachial index (ABI) is associated with increased morbidity and mortality in hemodialysis patients. However, whether the decrease in ABI over time carries the prognostic value is unknown. The aim of this study was to assess whether the decrease in ABI over time was a good predictor of poor cardiovascular (CV) prognosis in hemodialysis patients. METHODS:This study enrolled 234 routine hemodialysis patients and 173 patients completed the follow-up. The ABI was measured by an ABI-form device at baseline and at the first year follow-up. The ΔABI was defined as ABI measured at the first year follow-up minus ABI measured at baseline. Progressors of ABI were defined as patients with ΔABI < -0.3. CV events were defined as CV death, hospitalization for unstable angina, nonfatal myocardial infarction, hospitalization for arrhythmia, hospitalization for congestive heart failure and stroke. RESULTS:The follow-up period was 37.8 ± 11.1 months. In the multivariate analysis, progressors of ABI (hazard ratio, 2.71; 95% confidence interval, 1.10-6.68, P = 0.03), decreased albumin and increased high-sensitivity C-reactive protein were associated with increased CV events. CONCLUSIONS:This longitudinal study showed ΔABI < -0.3 was independently associated with an increase in CV events. Hence, a great decrease in ABI over time might be a useful indicator of poor CV prognosis in hemodialysis patients.
    背景与目标:
  • 【模拟牙髓压力对牙本质多合一粘合强度的影响。】 复制标题 收藏 收藏
    DOI:10.1016/j.jdent.2006.08.001 复制DOI
    作者列表:Hosaka K,Nakajima M,Yamauti M,Aksornmuang J,Ikeda M,Foxton RM,Pashley DH,Tagami J
    BACKGROUND & AIMS: OBJECTIVES:To evaluate the durability of all-in-one adhesive systems bonded to dentine with and without simulated hydrostatic pulpal pressure (PP). METHODS:Flat dentine surfaces of extracted human molars were prepared. Two all-in-one adhesive systems, One-Up Bond F (OBF) (Tokuyama Corp., Tokyo, Japan), and Fluoro Bond Shake One (FBS) (Shofu Co., Kyoto, Japan) were applied to the dentine surfaces under either a PP of 0 or 15cm H(2)O. Then, resin composite build-ups were made. The specimens bonded under pressure were stored in 37 degrees C water for 24h, 1 and 3 months under 15cm H(2)O PP. Specimens not bonded under pressure were stored under zero PP. After storage, the specimens were sectioned into slabs that were trimmed to hourglass shapes and subjected to micro-tensile bond testing (muTBS). The data were analysed using two-way ANOVA and Holm-Sidak HSD multiple comparison tests (alpha=0.05). RESULTS:The muTBS of OBF fell significantly (p<0.05) when PP was applied during bonding and storage, regardless of storage time. In contrast, although the muTBS of OBF specimens bonded and stored without hydrostatic pressure storage fell significantly over the 3 months period, the decrease was less than half as much as specimens stored under PP. In FBS bonded specimens, although there was no significant difference between the muTBS with and without hydrostatic pulpal pressure at 24h, by 1 and 3 months of storage under PP, significant reductions were seen compared with the control group without PP. CONCLUSION:The muTBS of OBF bonded specimens was lowered more by simulated PP than by storage time; specimens bonded with FBS were not sensitive to storage time in the absence of PP, but showed lower bond strengths at 1 and 3 months in the presence of PP.
    背景与目标:
  • 【短暂的右心室压力超负荷后,右心室功能障碍持续存在。】 复制标题 收藏 收藏
    DOI:10.1016/s0008-6363(97)00038-2 复制DOI
    作者列表:Greyson C,Xu Y,Cohen J,Schwartz GG
    BACKGROUND & AIMS: OBJECTIVE:Acute pulmonary hypertension may cause right ventricular (RV) contractile failure. While it has been assumed that restoration of normal loading conditions after acute pulmonary hypertension is sufficient for complete recovery of RV function, this has not been rigorously examined. The purpose of this study was to test the hypothesis that acute RV pressure overload produces RV contractile dysfunction that persists following restoration of control loading conditions. METHODS:We subjected 18 autonomically-blocked, chloralose-anesthetized, open-chest pigs to 1 h of pulmonary artery constriction to increase RV systolic pressure from 35 +/- 1 to 55 +/- 1 mmHg, followed by 2 h of measurements after pulmonary artery constriction release. We determined regional RV free wall function from pressure-segment length loops and preload recruitable stroke work relations, and global RV function from stroke work vs. end-diastolic pressure relations. RESULTS:As expected, RV free wall systolic shortening diminished during pulmonary artery constriction, but the endo/epi blood flow ratio, lactate uptake, and coronary venous pH were not significantly changed. Following release of pulmonary artery constriction, RV systolic and diastolic pressure returned to control values. Nonetheless, contractile dysfunction persisted, with depressed RV free wall systolic shortening (70 +/- 22% of control), RV regional external work (59 +/- 11% of control at control end-diastolic length), and global RV stroke work (56 +/- 14% of control at control end-diastolic pressure). Depressed regional work was due to a parallel, rightward shift of the preload recruitable stroke work relation. Five pigs identically instrumented but not subjected to pulmonary artery constriction showed no significant over 3 h. CONCLUSIONS:Acute pulmonary hypertension causes RV contractile dysfunction that persists at least 2 h after restoration of control loading conditions. Contractile dysfunction is not attributable to RV ischemia during pressure overload.
    背景与目标:
  • 【三维导航门控全心脏MR冠状动脉造影的评估: 高心率受试者的收缩期成像的重要性。】 复制标题 收藏 收藏
    DOI:10.1016/j.ejrad.2006.08.013 复制DOI
    作者列表:Wu YW,Tadamura E,Yamamuro M,Kanao S,Nakayama K,Togashi K
    BACKGROUND & AIMS: PURPOSE:To evaluate the influence of heart rate (HR) on magnetic resonance coronary angiography (MRCA) image quality in diastolic and systolic phases. MATERIALS AND METHODS:Twenty-seven healthy volunteers (9 men; 33+/-9 years, HR 53-110 bpm), were evaluated with the electrocardiography and three-dimensional navigator-gating MRCA in a 1.5-T MR scanner (Avanto, Siemens) in diastolic and systolic phases (steady-state free precession; TR/TE/flip angle=3.2 ms/1.6 ms/90 degrees). The timing of scanning was individually adapted to the cardiac rest periods obtained in the prescanning, by visually identifying when the movement of right coronary artery was minimized during diastole and systole. Images of two phases were side-by-side compared on a four-point scale (from 1=poor to 4=excellent visibility; score of 3 or 4 as diagnostic). RESULTS:Of 13 subjects with HR < or =65 bpm (low HR group, mean 59.8+/-4.9 bpm, range 53-65), the image quality scores were significantly better than that with higher heart rates (73.9+/-9.0 bpm, range 68-110) in diastolic MRCA. The image quality was significantly improved during systole in high HR group. Overall, 91.3% of low HR group had MRCA image of diagnostic quality acquired at diastole, while 88.3% of high HR group had diagnostic images at systole by segmental analysis (p=NS). CONCLUSIONS:MRCA at systole offered superior quality in patients with high heart rates.
    背景与目标:
  • 【接受蒽环类药物化疗的HER2/neu阴性乳腺癌患者的左心室收缩功能: 12个月内左心室射血分数和心肌应变成像的比较分析。】 复制标题 收藏 收藏
    DOI:10.1016/j.ejca.2013.06.046 复制DOI
    作者列表:Stoodley PW,Richards DA,Boyd A,Hui R,Harnett PR,Meikle SR,Byth K,Stuart K,Clarke JL,Thomas L
    BACKGROUND & AIMS: AIM:Anthracycline agents are undermined by their cardiotoxicity. As life expectancy following treatment is greatly improved, techniques that ensure early detection and timely management of cardiotoxicity are essential. The aim of the present study was to evaluate left ventricular (LV) systolic function with LV ejection fraction (LVEF) and two-dimensional myocardial strain up to 12 months after anthracycline chemotherapy, specifically in HER2/neu negative breast cancer patients. METHODS:Seventy-eight consecutive anthracycline naïve breast cancer patients were studied before and immediately after anthracycline chemotherapy. Fifty HER2/neu negative patients were studied over 12 months with serial echocardiograms at four time points. All patients were treated with standard regimens containing anthracyclines. RESULTS:Global systolic strain was significantly reduced immediately after, and 6 months after anthracyclines (-19.0 ± 2.3% to -17.5 ± 2.3% (P<0.001) and -18.2 ± 2.2% (P=0.01) respectively). A non-uniform reduction in strain was observed each time with relative sparing of the LV apex. LVEF remained largely unchanged at both time points. Global strain normalised by 12 months in the majority of patients. Persistently reduced strain was observed in 16% (n=8); these patients had a greater reduction in strain at 6 months (≤ -17.2%), and had received higher cumulative anthracycline doses. CONCLUSION:Myocardial strain imaging is more sensitive than LVEF for the early detection and intermediate term monitoring of LV systolic function following anthracycline chemotherapy in HER2/neu negative breast cancer patients, and may aid in the development of improved monitoring protocols.
    背景与目标:
  • 【Nadolol在原发性高血压中的作用: 对动态血压,肾血流动力学和心功能的影响。】 复制标题 收藏 收藏
    DOI:10.1111/j.1365-2125.1985.tb05037.x 复制DOI
    作者列表:Dupont AG,Vanderniepen P,Bossuyt AM,Jonckheer MH,Six RO
    BACKGROUND & AIMS: :Chronic administration of nadolol has been reported to reduce blood pressure either without or with a concomitant fall of renal blood flow. We therefore studied the effects of nadolol 80 mg once daily on ambulatory blood pressure, renal and systemic haemodynamics in patients with mild to moderate essential hypertension. Ten patients took part in this randomized, double-blind, placebo-controlled, crossover study, each phase of which lasted 4 weeks. Nadolol significantly reduced ambulatory blood pressure and heart rate, but had no effect on blood pressure variability. Cardiac output was significantly reduced by nadolol and total peripheral resistance increased but without reaching statistical significance. Despite the fall in blood pressure and cardiac output, renal blood flow and glomerular filtration rate remained unchanged. The fraction of cardiac output reaching the kidneys rose significantly and renal vascular resistance was significantly reduced. Body weight, urinary sodium excretion and urine flow rate remained unchanged. We conclude that nadolol 80 mg once daily lowers ambulatory blood pressure in patients with mild to moderate hypertension without impairment of renal blood flow, indicating a redistribution of cardiac output to the kidneys. The mechanism of the renal vasodilator effect of nadolol remains to be determined.
    背景与目标: : 据报道,长期服用nadolol可以降低血压,而不会或伴随肾血流下降。因此,我们研究了nadolol 80 mg每天一次对轻度至中度原发性高血压患者的动态血压,肾脏和全身血流动力学的影响。10名患者参加了这项随机,双盲,安慰剂对照,交叉研究,每个阶段持续4周。Nadolol显着降低了动态血压和心率,但对血压变异性没有影响。nadolol显着降低了心输出量,总外周阻力增加了,但没有达到统计学意义。尽管血压和心输出量下降,但肾血流量和肾小球滤过率保持不变。到达肾脏的心输出量的比例显着增加,肾脏血管阻力显着降低。体重,尿钠排泄和尿流率保持不变。我们得出的结论是,nadolol 80 mg每天一次可降低轻度至中度高血压患者的动态血压,而不会损害肾血流,这表明心输出量重新分布到肾脏。那多洛尔的肾血管扩张作用的机制仍有待确定。
  • 【由于左心室收缩功能降低而导致心力衰竭患者的贫血和相关的临床结局。】 复制标题 收藏 收藏
    DOI:10.1002/clc.22181 复制DOI
    作者列表:McCullough PA,Barnard D,Clare R,Ellis SJ,Fleg JL,Fonarow GC,Franklin BA,Kilpatrick RD,Kitzman DW,O'Connor CM,Piña IL,Thadani U,Thohan V,Whellan DJ,HF-ACTION Investigators.
    BACKGROUND & AIMS: BACKGROUND:Anemia is associated with decreased functional capacity, reduced quality of life, and worsened outcomes among patients with heart failure (HF) due to reduced left ventricular ejection fraction (HFREF). We sought to evaluate the independent effect of anemia on clinical outcomes among those with HFREF. HYPOTHESIS:Anemia is associated with cardiovascular events in patients with heart failure. METHODS:The HF-ACTION trial was a prospective, randomized trial of exercise therapy vs usual care in 2331 patients with HFREF. Patients with New York Heart Association class II to IV HF and left ventricular ejection fractions of ≤ 35% were recruited. Hemoglobin (Hb) was measured up to 1 year prior to entry and was stratified by quintile. Anemia was defined as baseline Hb <13 g/dL and <12 g/dL in men and women, respectively. Hemoglobin was assessed in 2 models: a global prediction model that had been previously developed, and a modified model including variables associated with anemia and the studied outcomes. RESULTS:Hemoglobin was available at baseline in 1763 subjects (76% of total study population); their median age was 59.0 years, 73% were male, and 62% were Caucasian. The prevalence of anemia was 515/1763 (29%). Older age, female sex, African American race, diabetes, hypertension, and lower estimated glomerular filtration rates were all more frequent in lower Hb quintiles. Over a median follow-up of 30 months, the primary outcome of all-cause mortality or all-cause hospitalization occurred in 78% of those with anemia and 64% in those without (P < 0.001). The secondary outcomes of all-cause mortality alone,cardiovascular (CV) mortality or CV hospitalization, and CV mortality or HF hospitalization occurred in 23% vs 15%, 67% vs 54%, and 44 vs 29%, respectively (P < 0.001). Heart failure hospitalizations occurred in 36% vs 22%, and urgent outpatient visits for HF exacerbations occurred in 67% and 55%, respectively (P < 0.001). For the global model, there was an association observed for anemia and all-cause mortality or hospitalization (adjusted hazard ratio [HR]: 1.15, 95% confidence interval [CI]: 1.01-1.32, P = 0.04), but other outcomes were not significant at P < 0.05. In the modified model, the adjusted HR for anemia and the primary outcome of all-cause mortality or all-cause hospitalization was 1.25 (95% CI: 1.10-1.42, P < 0.001). There were independent associations between anemia and all-cause death (HR: 1.11, 95% CI: 0.87-1.42, P = 0.38), CV death or CV hospitalization (HR: 1.16, 95% CI: 1.01-1.33, P = 0.035), and CV death and HF hospitalization (HR: 1.27, 95% CI: 1.06-1.51, P = 0.008). CONCLUSIONS:Anemia modestly is associated with increased rates of death, hospitalization, and HF exacerbation in patients with chronic HFREF. After adjusting for other important covariates, anemia is independently associated with an excess hazard for all-cause mortality and all-cause hospitalization. Anemia is also associated with combinations of CV death and CV/HF hospitalizations as composite endpoints.
    背景与目标:
  • 【三尖瓣环形平面收缩偏移在法洛四联症修复后儿童和青少年右心室功能评估中的应用。】 复制标题 收藏 收藏
    DOI:10.1016/j.echo.2013.06.022 复制DOI
    作者列表:Mercer-Rosa L,Parnell A,Forfia PR,Yang W,Goldmuntz E,Kawut SM
    BACKGROUND & AIMS: BACKGROUND:Assessing right ventricular (RV) performance is essential for patients with tetralogy of Fallot (TOF). The aim of this study was to investigate the reliability and validity of tricuspid annular plane systolic excursion (TAPSE) against cardiac magnetic resonance imaging measures and cardiopulmonary exercise testing. METHODS:A retrospective study was performed in 125 outpatients with repaired TOF with available protocol-driven echocardiography, cardiac magnetic resonance imaging, and exercise stress testing obtained as part of a cross-sectional study. TAPSE was measured on the two-dimensional apical four-chamber view on echocardiography by two readers. Multivariate linear regression was used to examine the association between TAPSE and measures of RV function and exercise capacity. RESULTS:The mean age was 12.6 ± 3.3 years, 41 patients (33%) were female, and 104 (83%) were white. TAPSE averaged 1.6 ± 0.37 cm, with an interreader intraclass correlation coefficient of 0.78 (n = 18). TAPSE was significantly associated with cardiac magnetic resonance-based RV stroke volume after adjustment for gender and body surface area (β = 13.8; 95% confidence interval, 2.25-25.30; P = .02). TAPSE was not associated with cardiac magnetic resonance-based RV ejection fraction (P = .77). On exercise testing, TAPSE was not associated with peak oxygen consumption, percentage of predicted oxygen consumption, oxygen pulse, or the ventilatory equivalent for carbon dioxide in patients with maximal exercise stress testing (n = 73 [58%]). CONCLUSIONS:TAPSE is reproducibly measured by echocardiography in patients with TOF. It is not associated with RV ejection fraction or exercise performance, and its association with RV stroke volume may be confounded by body size. On the basis of these results, TAPSE is not representative of global RV performance in patients with TOF.
    背景与目标:
  • 【足底压力分布与鞋垫舒适度的关系。】 复制标题 收藏 收藏
    DOI:10.1016/0268-0033(94)90062-0 复制DOI
    作者列表:Che H,Nigg BM,de Koning J
    BACKGROUND & AIMS: :In this paper, four pairs of insoles with different comfort characteristics were used to investigate the relationship between the pressure distribution under the foot and running shoe comfort. Fourteen male subjects were tested in four insole conditions by walking and running on a treadmill. The pressure at the plantar surface of the foot was measured by using an EMED pressure-measuring insole. For walking there were significantly higher pressures and forces in the midfoot area and significantly lower pressures in the medial forefoot and hallux area by wearing the most comfortable insole compared with wearing the least comfortable insole. The shift of the pressure from forefoot to midfoot for the most comfortable insole provided an even distribution of the pressure at the plantar surface of the foot. The results also demonstrated that the path of centre of force at the plantar surface of the foot moved to the lateral aspect of the foot for the most comfortable insole. For running, only the pressure in the medial forefoot area was found significantly lower for the most comfortable insole than for the least comfortable insole. The results of this study indicated that the pressure distribution between the plantar surface of the foot and the shoe could detect the change of shoe comfort. Thus it is a suggestion that pressure measurement may be related to understand factors important for shoe comfort. Comfort of sport shoes is important for the appropriate execution of sport activities. Additionally, comfort may influence fatigue and possibly the development of injuries. The quantification of comfort of sport shoes and the understanding of mechanical and/or biological functions related to it may be enhanced with the use of pressure measurements between the plantar surface of the foot and the shoe sole.
    背景与目标: : 本文采用四对舒适特性不同的鞋垫,研究了脚底压力分布与跑鞋舒适度之间的关系。通过在跑步机上行走和跑步,在四种鞋垫条件下对十四名男性受试者进行了测试。使用EMED测压鞋垫测量脚的足底表面的压力。步行时,与穿着最不舒适的鞋垫相比,穿着最舒适的鞋垫,中足区域的压力和力量明显更高,而前足内侧和拇趾区域的压力明显更低。对于最舒适的鞋垫,压力从前脚向中脚的转移提供了脚的足底表面压力的均匀分布。结果还表明,对于最舒适的鞋垫,脚的足底表面的力中心路径移至脚的侧面。对于跑步,最舒适的鞋垫仅发现前脚内侧区域的压力明显低于最不舒适的鞋垫。这项研究的结果表明,足底和鞋子之间的压力分布可以检测到鞋子舒适度的变化。因此,建议压力测量可能与了解对鞋舒适性重要的因素有关。运动鞋的舒适性对于适当执行体育活动很重要。此外,舒适性可能会影响乏力,并可能影响伤害的发展。可以通过使用脚的足底表面和鞋底之间的压力测量来增强对运动鞋的舒适性的量化以及对与其相关的机械和/或生物学功能的理解。
  • 【踝关节融合术对步行的影响: 运动学和动力学研究。】 复制标题 收藏 收藏
    DOI:10.1016/0268-0033(90)90025-2 复制DOI
    作者列表:Marshall R,Wood G,Nade S
    BACKGROUND & AIMS: :We have studied the effects of ankle arthrodesis on the gait of three subjects with special attention to the time and sagittal plane kinematic and kinetic characteristics. Each subject had a painless arthrodesis and no other gait limitation. To compensate for this disability they showed an increased range of movement at the ipsilateral mid-tarsal, knee and hip joints, and required greater than normal resuftan joint moments to be generated at the ipsilateral knee and hip joints. The subjects exhibited stride-to-stride kinetic compensation at the knee and hip joints, with associated variability in resultant joint moments and power patterns. However, they achieved a symmetric gait by mimicking ipsilateral movements with the opposite limb.
    背景与目标: : 我们研究了踝关节固定术对三名受试者步态的影响,特别注意时间和矢状面运动学和动力学特征。每个受试者都有无痛性关节固定术,没有其他步态限制。为了弥补这种残疾,他们显示同侧中,膝和髋关节的运动范围增加,并且需要在同侧膝关节和髋关节处产生比正常的resuftan关节力矩更大的运动。受试者在膝关节和髋关节表现出步幅运动补偿,并在关节力矩和动力模式上产生相关的变异性。但是,他们通过模仿与相反肢体的同侧运动来实现对称步态。
  • 【缬沙坦可独立于降低血压而改善2型糖尿病的动脉僵硬度。】 复制标题 收藏 收藏
    DOI:10.1161/HYPERTENSIONAHA.108.111674 复制DOI
    作者列表:Karalliedde J,Smith A,DeAngelis L,Mirenda V,Kandra A,Botha J,Ferber P,Viberti G
    BACKGROUND & AIMS: :Increased arterial stiffness, as estimated from aortic pulse wave velocity (Ao-PWV), and albuminuria are independent predictors for cardiovascular disease in type 2 diabetes mellitus (T2DM). Whether angiotensin receptor blockers (ARBs), drugs with cardio-renal protective effects, improve Ao-PWV to a greater extent than other equipotent antihypertensive medications remains unclear. After a 4-week washout phase, we compared the effects of valsartan (n=66), an ARB, with that of amlodipine (n=65), a calcium channel blocker on Ao-PWV in 131 T2DM patients with pulse pressure (PP) >or=60 mm Hg and raised albumin excretion rate (AER) in a 24-week randomized, double-blind, parallel group study. Hydrochlorothiazide (HCTZ) 25 mg/d was added to valsartan 160 mg and amlodipine 5 mg/od uptitrated to 10 mg/od after 4 weeks to ensure equivalent BP control. After 24 weeks brachial and central aortic PP had fallen to a similar extent with attained mean (SD) brachial and central PP of 61.6 (13.6) and 47.3 (14.1) mm Hg in the valsartan/HCTZ group and 61.5 (12.2) and 47.3 (9.9) mm Hg in the amlodipine group, respectively. Ao-PWV showed a significantly greater reduction, mean (95% CI), -0.9 m/s (-1.4 to -0.3) for valsartan/HCTZ compared to amlodipine (P=0.002). AER fell significantly only with Val/HCTZ from 30.8(20.4, 46.5) to 18.2(12.5, 26.3) mcg/min, (P=0.01) with between treatment difference in favor of Val/HCTZ of -15.3mcg/min (P<0.001). Changes in AER and Ao-PWV were not correlated. Valsartan/HCTZ improves arterial stiffness and AER to a significantly greater extent than amlodipine despite similar central and brachial BP control. These 2 effects, which appear independent of each other, may explain the specific cardio-renal protective properties of ARBs.
    背景与目标: : 根据主动脉脉搏波速度 (Ao-PWV) 估计,动脉僵硬度增加和蛋白尿是2型糖尿病 (T2DM) 心血管疾病的独立预测因素。血管紧张素受体阻滞剂 (arb) 是具有心肺保护作用的药物,是否比其他同等降压药物在更大程度上改善Ao-PWV尚不清楚。经过4周的冲洗阶段,我们比较了缬沙坦 (n = 66) (ARB) 和氨氯地平 (n = 65) 的作用,在一项为期24周的随机,双盲,平行组研究中,131例脉压 (PP)> 或 = 60毫米Hg且白蛋白排泄率 (AER) 升高的T2DM患者的Ao-PWV钙通道阻滞剂。将氢氯噻嗪 (HCTZ) 25 mg/d添加至缬沙坦160 mg,并在4周后将氨氯地平5 mg/od上调至10 mg/od,以确保等效的BP控制。24周后,在缬沙坦/HCTZ组和61.5 (12.2) 和47.3 (9.9) mm Hg的平均 (SD) 肱动脉和中央PP下降到类似的程度,达到61.6 (13.6) 和47.3 (14.1) mm Hg在氨氯地平组,分别。与氨氯地平 (P = 0.002) 相比,缬沙坦/HCTZ的Ao-PWV降低幅度明显更大,平均 (95% CI),-0.9 m/s (-1.4至-0.3)。仅Val/HCTZ从30.8(20.4,46.5) 到18.2(12.5,26.3) mcg/min,AER显着下降 (P = 0.01),两种治疗之间的差异有利于Val/HCTZ为-15.3mcg/min (P<0.001)。AER和Ao-PWV的变化不相关。尽管中枢和肱动脉血压控制相似,但缬沙坦/HCTZ比氨氯地平在更大程度上改善了动脉僵硬度和AER。这两种作用似乎彼此独立,可以解释arb的特定心肺保护特性。
  • 【左心室收缩功能障碍患者心率的小波变换模极大值和多重分形去趋势波动分析的比较。】 复制标题 收藏 收藏
    DOI:10.1111/j.1542-474X.2008.00215.x 复制DOI
    作者列表:Galaska R,Makowiec D,Dudkowska A,Koprowski A,Chlebus K,Wdowczyk-Szulc J,Rynkiewicz A
    BACKGROUND & AIMS: BACKGROUND:In recent years the WTMM (wavelet transform modulus maxima) and MDFA (multifractal detrended fluctuation analysis) methods have become widely used techniques for the determination of nonlinear, multifractal heart rate (HR) dynamics. The purpose of our study was to compare multifractal parameters of heart rate calculated using both methods in a group of 90 patients with reduced left ventricular systolic function (rlvs group) and in a group of 39 healthy persons (nsr group). METHODS:For each subject from the rlvs group (LVEF < or =40%) and the nsr group, a 24-hour ECG Holter monitoring was performed. The width of the multifractal spectrum and global Hurst exponent were calculated by means of WTMM and MDFA methods for 5-hour daytime and nighttime subsets. RESULTS:The width of the multifractal spectrum was significantly lower and the Hurst exponent was significantly higher in rlvs group in comparison to nsr group both during diurnal activity and nocturnal rest according to MDFA and only during diurnal activity according to WTMM method. In both groups we observed significant differences of the multifractal spectrum width and the global Hurst exponent between the nighttime and daytime recordings. CONCLUSIONS:MDFA seems to be more sensitive as compared with WTMM method in differentiation between multifractal properties of the heart rate in healthy subjects and patients with left ventricular systolic dysfunction.
    背景与目标:
  • 【大鼠正中网状核神经元对化学刺激和血压变化的反应。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Lin AM,Wang Y,Su CK,Lee EH,Kuo JS,Chai CY
    BACKGROUND & AIMS: :Previous studies have shown that paramedian reticular nucleus (PRN) possessed sympathetic and parasympathetic inhibitions on autonomic nervous system. In the present study, the cardiovascular reactions of PRN by locally-applied DL-homocysteic acid (DLH), acetylcholine (ACh), monoamines and electrophysiological properties of PRN neurons responding to intravenous injection of ACh and NE were studied in adult Sprague-Dawley rats. In PRN, electrical stimulation caused hypotension and mild bradycardia while microinjection of DLH, which excites only cell body of the neurons but not passing fibers, evoked similar responses. Furthermore, direct application of ACh, norepinephrine (NE) or serotonin (5-HT) in PRN also produced hypotension, suggesting that these putative neurotransmitters may be involved in the cardiovascular responses in PRN. The electrophysiological properties of PRN neurons were studied: Neurons in PRN could be categorized into three types according to their neuronal activities in response to the changes of systemic arterial blood pressure (SAP) by ACh or NE given intravenously. Type I neurons (25/69) were activated in the same direction of SAP changes. Type II neurons (17/69) responded opposite to the direction of SAP changes. Type III neurons (27/69) responded inconsistently to the changes of SAP. All the three types of neurons were excited by locally-applied DLH and possessed a similar unfiltered action potential duration of greater than 0.5 msec.
    背景与目标: : 先前的研究表明,正中网状核 (PRN) 对自主神经系统具有交感和副交感神经抑制作用。在本研究中,在成年Sprague-Dawley中研究了局部应用DL-同型半胱氨酸 (DLH),乙酰胆碱 (ACh),单胺和PRN神经元对静脉注射ACh和NE的反应的心血管反应。大鼠。在PRN中,电刺激引起低血压和轻度心动过缓,而微量注射DLH仅激发神经元的细胞体而不通过纤维,引起类似的反应。此外,在PRN中直接应用ACh,去甲肾上腺素 (NE) 或5-羟色胺 (5-HT) 也会产生低血压,这表明这些假定的神经递质可能与PRN的心血管反应有关。研究了PRN神经元的电生理特性: 根据静脉内给药的ACh或NE对全身动脉血压 (SAP) 变化的响应,PRN中的神经元可分为三种类型。I型神经元 (25/69) 在SAP变化的同一方向被激活。II型神经元 (17/69) 对SAP变化的方向相反。III型神经元 (27/69) 对SAP的变化反应不一致。所有三种类型的神经元均由局部应用的DLH激发,并具有大于0.5毫秒的类似的未经过滤的动作电位持续时间。
  • 【17β-雌二醇可预防去卵巢大鼠的氧化应激并降低血压。】 复制标题 收藏 收藏
    DOI:10.1152/ajpregu.2000.279.5.R1599 复制DOI
    作者列表:Hernández I,Delgado JL,Díaz J,Quesada T,Teruel MJ,Llanos MC,Carbonell LF
    BACKGROUND & AIMS: :In this study, we tested whether estrogen deficiency is associated with oxidative stress and decreased nitric oxide (NO) production, which could be responsible for an increased blood pressure in ovariectomized rats. Hemodynamic studies were performed on conscious, chronically instrumented rats. Chronic estrogen replacement on ovariectomized rats lowered blood pressure approximately 13 mmHg, from 119 +/- 3 mmHg in ovariectomized rats to 106 +/- 3 mmHg in ovariectomized-treated rats; it was also accompanied by an increase in cardiac index and vascular conductance, achieving hemodynamic values similar to those shown by sham-operated rats. N(G)-nitro-L-arginine methyl ester administration lowered significantly less the vascular conductance (0.14 +/- 0.01 vs. 0.22 +/- 0.03 and 0.26 +/- 0.01 ml. min(-1). mmHg(-1)/100 g; P < 0.05) in ovariectomized rats than in the sham-operated and estrogen-treated ovariectomized rats, respectively. Estrogen replacement prevented the lower plasma levels of nitrites/nitrates observed in ovariectomized rats. The lower plasma total antioxidant status and reduced thiol groups and the increase in plasma lipoperoxides presented in ovariectomized animals were reestablished with the estrogen treatment. These results show that estrogen administration decreases blood pressure and increases vascular conductance in ovariectomized rats. This effect may be related to an increase in NO synthesis and/or preventing oxidative stress, then improving endothelial function.
    背景与目标: : 在这项研究中,我们测试了雌激素缺乏是否与氧化应激和一氧化氮 (NO) 产生减少有关,这可能是卵巢切除大鼠血压升高的原因。对有意识的慢性器械大鼠进行了血液动力学研究。去卵巢大鼠的慢性雌激素替代使血压降低约13 mmHg,从去卵巢大鼠的119/- 3 mmHg降至去卵巢治疗大鼠的106/- 3 mmHg; 它还伴随着心脏指数和血管电导的增加,达到与假手术大鼠相似的血流动力学值。N(G)-硝基-L-精氨酸甲酯给药显著降低血管电导 (0.14 +/- 0.01 vs. 0.22 +/- 0.03和0.26 +/-0.01毫升.min(-1). mmHg(-1)/100g; 在去卵巢大鼠中,P <0.05) 分别比在假手术和雌激素处理的去卵巢大鼠中。雌激素替代可防止在卵巢切除的大鼠中观察到较低的血浆亚硝酸盐/硝酸盐水平。通过雌激素治疗,可以恢复卵巢切除动物中较低的血浆总抗氧化剂状态和硫醇基团的减少以及血浆脂质过氧化物的增加。这些结果表明,雌激素给药可降低去卵巢大鼠的血压并增加血管电导。这种作用可能与增加NO合成和/或防止氧化应激,然后改善内皮功能有关。

+1
+2
100研值 100研值 ¥99课程
检索文献一次
下载文献一次

去下载>

成功解锁2个技能,为你点赞

《SCI写作十大必备语法》
解决你的SCI语法难题!

技能熟练度+1

视频课《玩转文献检索》
让你成为检索达人!

恭喜完成新手挑战

手机微信扫一扫,添加好友领取

免费领《Endnote文献管理工具+教程》

微信扫码, 免费领取

手机登录

获取验证码
登录