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71.
Aerobic endurance capacity is partly dependent on blood supply to and metabolic capacity of the active muscles. Recordings of lower limb skin postocclusive hyperaemia with laser Doppler flowmetry can differentiate between patients with lower limb atherosclerosis and healthy controls. In this study, we investigated the relationship between aerobic endurance, calf volume, common femoral artery diameter and time properties of the postocclusive laser Doppler curve. A group of 16 healthy male subjects with values for aerobic endurance which varied from those of untrained men to elite endurance trained athletes were examined. Duration of laser Doppler recorded skin postocclusive hyperaemia was significantly correlated to both aerobic power and anaerobic threshold (P less than 0.01). Hyperaemia in subjects with large common femoral artery diameter was of shorter duration (P less than 0.05). The peak and mean body mass related blood flow during hyperaemia was correlated to anaerobic threshold (P less than 0.05). These results were in agreement with previous studies indicating an effect of endurance training on the blood supply to the muscles concerned.  相似文献   
72.
目的:探讨应用多普勒组织运动成像技术(Dopplar Tissue Imaging,DTI)研究二尖瓣环6位点组织运动评估心肌梗死局部及左室整体功能。方法:选取我院心内科及急诊科住院患者,临床上经心肌酶学、心电图、及冠脉造影确诊为心肌梗死患者86例。根据造影结果将其分组:左主干病变7例;前降支病变46例;右冠病变25例;回旋支病变8例;另选取性别、年龄相当的健康志愿者作为对照组。分别进行常规超声心动图检查及二尖瓣环6位点DTI参数测定。将病例组二尖瓣环组织运动速度参数与对照组进行对比分析。结果:1).左主干病变组二尖瓣环3,5位点、1位点DTI参数及6位点DTI参数s波较均值较对照组明显降低(P0.01);2).前降支病变组和右冠病变组二尖瓣环3,5位点DTI参数s波较对照组明显降低(P0.01,)1位点及6位点均值DTI参数s波较对照组明显降低(P0.05);3).回旋支病变组二尖瓣环2,6位点DTI参数s波较对照组明显降低(P0.05,)1位点及6位点均值DTI参数s波较对照组未见明显降低(P0.05)4).1位点s波与6位点s波均值与左室EF相关性好,r=0.898和r=0.934.6.左室EF与二尖瓣环1位点s波与心肌梗塞指数呈负相关(r=-0.763)。结论:二尖瓣环6位点组织运动速度可以定量评价心肌梗死局部心肌功能,二尖瓣环位点1与6位点组织运动速度均值相近可定量评价左心室整体功能。  相似文献   
73.
A group of 20 healthy volunteers [10 women, 10 men; median age 25 (20–33) years] were examined by means of pulsed wave Doppler echocardiography, blood sample analysis and psychological testing before and after listening to three different examples of music: a waltz by J. Strauss, a modern classic by H. W. Henze, and meditative music by R. Shankar. To assess small haemodynamic changes, mitral flow, which reflects left ventricular diastolic behaviour, was measured by Doppler ultrasound. Heart rate, arterial blood pressure and plasma concentrations of adrenocorticotropic hormone, cortisol, prolactin, adrenaline, noradrenaline, atrial natriuretic peptide (ANP) and tissue plasminogen activator (t-PA) were determined simultaneously. Transmitral flow profile is characterized by early E-wave and late atrial induced A-wave. Velocity-time integrals were measured and the atrial filling fraction was calculated. The mental state was measured by using a psychological score (Zerssen) with low values (minimum 0) for enthusiastic and high values (maximum 56) for depressive patterns. Music by J. Strauss resulted in an increase of atrial filling fraction (AFF; 29% vs 26%;P<0.05) and ANP (63 pg·ml–1 vs 60 pg·ml–1;P<0.05). The mental state was improved (Zerssen: 6.5 vs 11 points;P<0.05). After the music of H. W. Henze prolactin values were lowered (7.7 ng·ml–1 vs 9.1 ng·ml–1;P<0.01). The music of R. Shankar led to a decrease of cortisol concentrations (57 ng·ml–1 vs 65 ng·ml–1;P<0.001), noradrenaline concentrations (209 g·l–1 vs 256 g·l–1;P<0.01) andt-PAantigen concentrations (1.1 ng·ml–1 vs 1.4 ng·ml–1;P<0.05). Heart rate and blood pressure remained unchanged during the whole experiment. We concluded that different types of music induced changes of left ventricular diastolic function and plasma hormone concentrations. After rhythmic music (Strauss) AFF and ANP increased significantly, the mental state being improved. Meditative music (Shankar) lowered plasma cortisol, noradrenaline and t-PA concentrations; the observed increase of early left ventricular filling was not statistically significant. Prolactin concentrations decreased after modern music (Henze). Thus, it would seem to be possible to detect cardiovascular changes following different types of music by Doppler ultrasound and hormone analysis, meditative music having promising therapeutic implications in the treatment of conditions of stress.This paper contains data from J. Vollert's work for his doctoral degree.  相似文献   
74.
The stroke volume of the left ventricle (SV) was calculated from noninvasive recordings of the arterial pressure using a finger photoplethysmograph and compared to the values obtained by pulsed Doppler echocardiography (PDE). A group of 19 healthy men and 12 women [mean ages: 20.8 (SD 1.6) and 22.2 (SD 1.6) years respectively] were studied at rest in the supine position. The ratio of the area below the ejection phase of the arterial pressure wave (A s) to SV, as obtained by PDE, yielded a calibration factor dimensionally equal to the hydraulic impedance of the system (Z ao =A s ·SV –1). TheZ ao amounted on average to 0.062 (SD 0.018) mmHg · s · cm–3 for the men and to 0.104 (SD 0.024) mmHg · s · cm–3 for the women. TheZ ao was also estimated from the equation:Z ao = a · (d + b ·HR + c ·PP + e ·MAP)–1, whereHR was the heart rate,PP the pulse pressure,MAP the mean arterial pressure and the coefficients of the equation were obtained by an iterating statistical package. The value ofZ ao thus obtained allowed the calculation of SV from measurements derived from the photoplethysmograph only. The mean percentage error between the SV thus obtained and those experimentally determined by PDE amounted to 14.8 and 15.6 for the men and the women, respectively. The error of the estimate was reduced to 12.3 and to 11.1, respectively, if the factorZ ao, experimentally obtained from a given heart beat, was subsequently applied to other beats to obtain SV from theA s measurement in the same subject.  相似文献   
75.
应用多普勒超声法测定了拉萨市15名健康男性世居藏族和11名健康男性移居汉族静息时的颈内动脉平均血流速度(ICAMFV);以了解高原居民运动时ICAMFV、脑血流(CBF)和脑氧供应量的状况。结果表明:静息时两组ICAMFV、CBF及脑氧供应量相似;次极量运动时,两组的ICAMFV和脑氧供应量均增加;但在最大运动负荷时,仅世居组的ICAMFV及脑氧供应量增加。ICAMFV的增加可代偿最大运动时因SaO2降低所致的脑氧供应量下降。最大运动时世居组的脑氧供应量高于移居组,主要以CBF增加同时与维持较高的SaO2有关。脑氧供应量的增加可能与提高最大运动负荷能力有关。结果说明长期居住于高原的世居人和移居人运动时CBF反应己恢复到与平原相似的正常状态。  相似文献   
76.
目的:探讨灰阶超声和多普勒超声对甲状腺乳头状癌的诊断价值。方法:选取2013年9月~2014年9月在我院入院接受治疗的90例甲状腺乳头状癌。患者入院后,分别采用灰阶超声诊断和多普勒超声诊断对患者检查诊断,并对两种超声诊断方法的诊断率和对淋巴转移的诊断准确率进行比较分析,并对两种诊断方法的检查图像表现进行比较。结果:灰阶超声诊断诊断出82例,确诊率为91.1%,而多普勒超声诊断出85例,确诊率为94.4%。多普勒超声确诊率高于灰阶超声的,但无显著性差异(P0.05)。而灰阶超声诊断出有38例患者存在淋巴转移现象,诊断率为61.3%,多普勒超声诊断出有58例患者存在淋巴转移现象,诊断率为93.5%,多普勒超声的诊断率明显高于灰阶超声的,差异显著,具有统计学意义(P0.05)。结论:灰阶超声和多普勒超声对甲状腺乳头状癌都有较高的准确率,但多普勒超声在诊断患者是否有淋巴转移方面诊断率更高,结节内的血流信号更准确,其确诊率高达94.4%(P0.05)。通过检测有淋巴转移的患者的淋巴结内部的血管会变粗或增多等信息可提高淋巴转移的确诊率,具有可观的临床疗效。  相似文献   
77.
This paper presents a novel instrument for biosciences, useful for studies of moving embryos. A dual sequential imaging/measurement channel is assembled via a closed‐loop tracking architecture. The dual channel system can operate in two regimes: (i) single‐point Doppler signal monitoring or (ii) fast 3‐D swept source OCT imaging. The system is demonstrated for characterizing cardiac dynamics in Drosophila melanogaster larva. Closed loop tracking enables long term in vivo monitoring of the larvae heart without anesthetic or physical restraint. Such an instrument can be used to measure subtle variations in the cardiac behavior otherwise obscured by the larvae movements.

A fruit fly larva (top) was continuously tracked for continuous remote monitoring. A heartbeat trace of freely moving larva (bottom) was obtained by a low coherence interferometry based doppler sensing technique.  相似文献   

78.
动态模式多普勒仪是一种新型脑血流状况分析仪器。它采用波束方向上连续采样点的深度能量彩色编码直观地显示血流状况的二维信息,较业已成熟的经颅多普勒仪能够更加全面地获取和分析血流动力学参数,因而性能优越。本文结合经颅多普勒仪阐述动态模式显示的原理,对照频谱图介绍其显示方式和功能,并以显示实验来探索M-mode显示的实现方法。  相似文献   
79.
Indirect measurements of arterial blood pressure were made in African green monkeys (Cercopithecus aethiops) employing a Doppler ultrasound stethoscope and standard cuff and an Infrasonde automatic blood pressure recorder. Measurements were obtained from anesthetized (10 mg/kg ketamine (HCI) and unanesthetized (1.5 mg/kg ketamine HCI) animals. Ketamine had no significant effect on blood pressure. Indirect measurements from the brachial artery were compared with direct femoral artery measurements and with each other. Systolic blood pressures measured by the Doppler (r = .948) and Infrasonde (r = .920) methods correlated closely with direct measurements but were significantly lower than systolic blood pressures measured by the direct method. Diastolic blood pressures measured by the Infrasonde method agreed closely with direct measurements (r = .947). Systolic blood pressures measured by the indirect methods correlated closely in both anesthetized (r = .973) and unanesthetized (r = .834) animals and were not significantly different. Mean blood pressures calculated from direct and Infrasonde measurements also correlated closely (r = .963), with direct measurements being 4 mmHg higher on the average. Mean blood pressures are less influenced by methodology and are more reproducible than other pressures. These noninvasive methods can be used to obtain simple and accurate measurements of blood pressure from anesthetized and unanesthetized monkeys and are of value in long-term studies in monkeys.  相似文献   
80.
该文综述了应用高频彩色多普勒超声在血透患者动静脉内瘘( AVF)术前进行目标血管的选择,检查、筛选与定位,术后可用于监测动静脉内瘘( AVF)功能、流量、流速与各种并发症,以利于提高血透患者的生活质量与生存率。  相似文献   
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