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51.
K. H. Vogelberg M. Mühl M. Köhler 《Journal of molecular medicine (Berlin, Germany)》1987,65(15):713-718
Summary Seventy-five diabetic and 40 nondiabetic subjects who where suffering from peripheral vascular disease were studied in order to determine whether the degree of the severity of their disease can be better calculated by Doppler ultrasound examinations of the peak velocity than by the systolic pressure of the peripheral bloodstream. In 46 examinations of normal controls the mean value of the peak velocity was 13.3±3.3 cm/s with a standard deviation of 15.4%±13.2% on one day and 16.1%±15.9% on different days. Considering patients with or without diabetes mellitus the velocity was significantly decreased in correlation to an increasing degree of severity of the vascular disease (P<0.001); however, the decrease was lower in diabetic than in nondiabetic subjects (6.9±2.8 vs 4.6±6.2,P<0.05). The systolic pressure hardly decreased, but remained higher in all stages of peripheral vascular disease of diabetics than in the nondiabetic subject (P<0.05 toP<0.005). There was a significant decrease of the systolic pressure only in diabetic subjects with the most advanced degree of the disease, i.e. stage IV (P<0.05).It is concluded from this study that Doppler ultrasound measurements of the peak velocity of the peripheral bloodstream are a useful parameter to calculate the degree of severity of the peripheral vascular disease. In addition, it is concluded than peak velocity is an even better prognostic indicator of peripheral vascular disease than is measurement of the systolic blood pressure at the feet.
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献
52.
目的探讨二维超声和彩色多普勒血流显像(cDFI)对移植胰腺的功能和术后并发症的监测作用。方法用彩色多普勒超声观察6例移植胰腺的形态和血流动力学变化情况。结果(1)功能正常的移植胰腺在术后形态正常,体积偏大,主胰管内径正常,实质回声较正常胰腺略高,动脉PSV13~64cm/s,R10.44~0.68,P10.67~2.33。(2)2例出现急性排异和1例出现移植胰腺炎的移植胰腺周边出现低或无回声区,实质回声明显减低,分布不均。1例急性重度排异的RI值超过0.9,而另1例急性轻度排异RI值小于0.7。1例移植胰腺炎RI值超过0.9,PI值超过4.0。结论CDFI作为一种无创的检查技术对胰腺移植术后的监测和诊治具有积极意义。 相似文献
53.
54.
George Lourenço PhD Sabine Meunier MD PhD Marie Vidailhet MD PhD Marion Simonetta‐Moreau MD PhD 《Movement disorders》2007,22(4):523-527
A decrease of heteronymous median nerve-evoked inhibition of corticospinal projections to forearm extensor muscles was reported in a group of 10 dystonic patients by Bertolasi and colleagues in 2003. Here we tested the excitability of corticomotoneuronal connections to both wrist extensor (ECR) and flexor (FCR) muscles after conditioning stimulation of median and also radial nerve at rest in a group of 25 patients with focal hand dystonia compared to 20 healthy subjects. We also investigated the effect of the wrist dystonic posture, either in flexion or in extension, on the afferent modulation of ECR and FCR motor evolved potentials (MEPs). The heteronymous (median-induced) but also homonymous (radial-induced) inhibitions (interstimuli intervals 13-21 ms) of ECR MEP size observed in healthy subjects were decreased in patients. In addition, homonymous (median-induced) facilitation of FCR MEP size was also decreased in patients while heteronymous inhibition (radial-induced) was not. Neither the involvement of the target muscle in the dystonic posture nor the origin of the afferent volley (from a dystonic muscle) influenced the degree of impairment of afferent modulation of the MEP. These findings support the view that a global abnormal somatosensory coupling in focal hand dystonia may contribute to an inadequate motor command to wrist muscles. 相似文献
55.
TCD观察动脉瘤性SAH后脑血管痉挛的血流动力学改变 总被引:4,自引:0,他引:4
目的探讨动脉瘤性蛛网膜下腔出血(SAH)后脑血管痉挛的血流动力学改变。方法经CT、DSA证实为动脉瘤性SAH患者179例,床旁经颅超声多谱勒(TCD)在术前、术后1~3d、5~7d、9~11d、12~14d记录并分析大脑中动脉(M CA)的血流参数及频谱改变。结果M CA平均血流速度(Vm)于SAH后1~3d开始升高,5~7d、9~11d达到高峰;L I(血管痉挛指数)为3~6时预后良好;>6时可以出现神经系统功能损害,颅内压增高且有脑血管痉挛(CV S)者预后较差。结论TCD能无创、实时评价SAH后CV S的动态变化,可以推断SAH后CV S的严重程度及临床转归。 相似文献
56.
Torsades de pointes after intracoronary papaverine 总被引:2,自引:0,他引:2
Coronary blood flow velocity and coronary flow reserve can be assessed in humans using a coronary Doppler catheter and the vasodilator papaverine. Although it is a safe, elegant and reproducible technique, serious complications can occur. Coronary flow reserve assessment in a 49-year-old man with a critical stenosis in the proximal part of the circumflex artery was complicated by a papaverine-induced ventricular arrhythmia. Several features of the present case report support papaverine-induced disturbances of the repolarization phase as the pathophysiological mechanism: a 'torsade de pointes' pattern of the tachycardia, the lengthening of the QT-interval, the appearance of a new U-wave and the presence of additional risk factors (hypokalaemia and alcalosis). Patients presenting additional risk factors for this complication should be excluded from coronary flow reserve assessment. 相似文献
57.
目的 探讨下肢深静脉瓣功能不全的二维及彩色多普勒超声声像图改变。方法 应用二维及彩色多普勒超声检查下肢深静脉瓣功能不全36例,47条腿,观察下肢静脉血管及瓣膜的解剖结构和血流动力学改变。结果 有静脉瓣功能不全的患肢静脉管腔内径均有不同程度增宽,瓣膜均有不同程度的改变,脉冲多普勒显示返流频谱返流时间大于0.5s。结论 该检查对诊断下肢深静脉瓣功能不全有较高的实用价值。 相似文献
58.
59.
BACKGROUND AND PURPOSE: The Doppler waveform patterns of loss of diastolic flow, appearance of retrograde diastolic flow, or no detectable flow in the cerebral arteries suggest significantly abnormal cerebral blood flow (CBF). A retrospective study was performed to show that significantly abnormal CBF alone, without clinical criteria, is not necessarily specific to brain death in the young pediatric population. PATIENTS AND METHODS: Forty-seven pediatric patients, from newborn to 4 years of age, were found to have significantly abnormal CBF, including 7 patients with loss of diastolic flow, 28 with retrograde diastolic flow, and 23 with no detectable cerebral flow on serial Doppler sonographic examinations. Their clinical data and sonographic results were collected and analyzed. RESULTS: Forty-two patients died, a few of whom had only transient improvement of cerebral flow. All of the patients with no detectable cerebral flow expired. Five patients survived with or without sequelae. Their underlying conditions that caused increased intracranial pressure were treated by medical and/or surgical intervention, and diastolic reversal of CBF corrected within 1 day in all 5. CONCLUSIONS: Although no detectable flow is a lethal sign, pediatric patients with loss or reversal of diastolic flow may survive with prompt and effective treatment. Using Doppler ultrasound to diagnose cerebral circulatory arrest should be done with caution in pediatric patients. 相似文献
60.
Stefano Tamburin Antonio Fiaschi Domenico Idone Piergiorgio Lochner Paolo Manganotti Giampietro Zanette 《Movement disorders》2003,18(11):1316-1324
Hyperexcitability of the motor system has been reported in Parkinson's disease (PD). We evaluate how cutaneous afferents modulate motor excitability in PD patients and whether abnormal modulation is correlated to parkinsonian symptoms. Digital stimulation causes abnormal enhancement of motor responses in patients. This effect may be one of the features of motor hyperexcitability in PD. Cutaneomotor hyperexcitability correlates with clinical scores, suggesting that abnormal processing of cutaneous inputs might contribute to the pathogenesis of parkinsonian symptoms. 相似文献