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31.
恶性肿瘤累及颈动脉的外科处理   总被引:2,自引:1,他引:2  
为探讨头颈部恶性肿瘤侵犯颈动脉的外科治疗,对5例喉癌或下咽癌颈淋巴结转移累及一侧颈动脉病人,术前经CT或B超检查,3例经术前体外颈动脉压迫训练合格后手术切除受累段颈总动脉,2例系术中损伤颈总动脉后紧急切除受轻动脉。其中1例即刻行断端吻合,5例术中,术后均无明显脑缺血表现,3例术后随访2年以上健在,2例尚在随访中。  相似文献   
32.
To determine the effects of animal and artificial surfactants on cerebral haemodynamics, 20 premature babies receiving mechanical ventilation were randomized to receive Curosurf or Exosurf surfactant. Anterior cerebral artery blood flow velocity (CABFV) was measured using Doppler ultrasound before and up to 2 h after treatment. Following animal surfactant there was a rapid reduction in CABFV (median -36%, range -43% to +8%, p < 0:01), whereas artificial surfactant resulted in a slower rise which was less marked (median +20%, range -7% to +62%, p < 0:05). There were no significant changes in blood pressure. Two hours after administration, the oxygenation index (OI) improved significantly only in babies receiving animal surfactant. In this group there was a significant association between the change in CABFV at 1 min and the change in OI at 2 h ( r = 0:66, p < 0:05). Animal surfactant produces rapid improvements in ventilation which are associated with marked alterations in cerebral haemodynamics.  相似文献   
33.
A case of unusual longevity to the age of 58 years is reported for a female patient with complete transposition of the great arteries. The association with a wide atrial septal defect with intact interventricular septum may have contributed to the long survival without surgery. Factors determining intercirculatory mixing and systemic oxygen saturation may be the high pulmonary flow, the location of the anatomic communication, sufficient hemoglobin concentration to allow an adequate level of systemic resistance and recirculated systemic flow, and the belated development of pulmonary vascular disease.  相似文献   
34.
糖尿病患者下肢动脉管壁内膜-中层厚度的研究   总被引:4,自引:0,他引:4  
目的 研究糖尿病与动脉硬化性血管障碍的关系。方法 对60例糖尿病患者及60例非糖尿病患者进行超声检查,两侧下肢动脉内径(D)、内膜-中层厚度(IMT)、收缩期最高速度(Max)、舒张期速度(Min)、搏动指数(PI)、阻力指数(RI)及有无斑块形成,进行统计。结果 IMT糖尿病组较非糖尿病组增厚(P〈0.01),各项血流参数在糖尿 且与非糖尿病组间差别无显著性(P〈0.05)。结论 下肢动脉的IM  相似文献   
35.
The aim of this study was to determine long-term success of flexible tantalum stents for the treatment of ostial and truncal renal artery stenosis. Since 1989, flexible tantalum stents (type Strecker) were implanted in 34 patients (36 arteries, 25 ostial lesions, 11 truncal lesions) with uncontrollable renovascular hypertension, 9 of them in association with renal insufficiency. Stents were placed unilaterally in 32 patients, and bilaterally in 2 patients for the treatment of renal artery stenosis. Thirty-five of 36 lesions were atherosclerotic, including 5 recurrencies after previous percutaneous transluminal renal angioplasty (PTRA). One patient had Takayasu arteritis. Stents were implanted after unsuccessful PTRA of 11 truncal and 23 ostial lesions, and as a primary procedure in 2 ostial lesions. Follow-up examinations included blood pressure measurement, determination of serum creatinine level, color duplex sonography, or angiography. The technical success rate was 92 %. Technical failure included incorrect stent placement (1 of 36 lesions, 2.8 %), and stent dislocation (2 of 36 lesions, 5.6 %), and two stents were retrieved percutaneously. In one case of Takayasu arteritis, residual stenosis of 40 % was observed. After technically successful stent placement, 77 % of patients became normotensive with or without medication. In the remaining patients there was partial improvement with blood pressure between 140 and 180 mmHg. Renal function improved in 76 % of patients (completely in 3 of 8, 38 %; and partially in 3 of 8, 38 %). Primary patency rate including all stented lesions and initial technical failures was 82.4 % ± 6.8 (1 year) and 82.4 % ± 9.2 (3 years). After technically successful stent placement, patency rates were 89.9 ± 5.6 % (1 year), and 89.9 ± 7.6 % (3 years). For ostial lesions, primary patency rate was 87.9 ± 6.7 % (1 year) and 87.9 ± 9.2 % (3 years). Placement of flexible tantalum stents in renal arteries is technically demanding, especially in ostial lesions. Once placed successfully, stent patency rate is excellent. Received: 8 December 1999; Accepted: 23 February 2000  相似文献   
36.
BACKGROUND: It was the aim of this study to elucidate the influence of opioids on coronary vascular tone using the model of isolated porcine coronary artery segments. METHODs: We studied the effects of fentanyl (0.01, 0.1, 1.0 microg ml(-1)), alfentanil (0.1, 1.0, 10 microg ml(-1)), and sufentanil (0.01, 0.1, 1.0 microg ml(-1)) on the contractile response to three vasoconstrictors, acetylcholine, histamine and serotonin. RESULTS: Fentanyl (0.1, 1.0 microg x ml(-1)) dose-dependently attenuated the contractile response to acetylcholine, but not to histamine and serotonin. There were no differences in fentanyl's vasorelaxing potency between rings with intact and denuded endothelium. Alfentanil and sufentanil did not exert any significant influence on any of the vasoconstrictors tested. CONCLUSION: It is concluded that, in isolated porcine coronary artery rings, fentanyl at high concentrations has an attenuating effect on acetylcholine-induced contractions, which is independent of endothelial function, whereas alfentanil and sufentanil do not influence coronary vascular tone.  相似文献   
37.
RATIONALE AND OBJECTIVES: This study evaluated the efficacy of targeted computed tomographic (CT) angiography in the diagnosis of intracranial internal carotid artery (ICA) disease and compared the results of routine and targeted CT angiography. MATERIALS AND METHODS: Fifty-four patients (24 male and 30 female patients aged 2 months to 87 years) were examined with CT angiography. Digital subtraction angiography (DSA) was performed in 42. CT angiograms were reconstructed with the maximum-intensity projection (MIP) algorithm. Targeted CT angiography was performed by individually reconstructing a single ICA territory. Each ICA was divided into four segments, and findings of routine MIP CT angiography, routine MIP plus targeted CT angiography, and DSA were reviewed independently by two neuroradiologists for vascular lesions involving each segment. Routine and targeted CT angiograms were also evaluated to determine how well both ICAs were visualized. RESULTS: Routine CT angiography was rated good or excellent for ICA visualization in 64% of cases, compared with 81% for targeted CT angiography (P = .0005). The overall agreement between routine CT angiography and DSA and between routine plus targeted CT angiography and DSA was 92% and 94%, respectively. There was no statistically significant difference between the percentages of vascular lesions detected with routine CT angiography alone and with routine plus targeted CT angiography. Both methods tended to show false-positive findings of steno-occlusive disease, but targeted CT angiography showed details of aneurysms and stenotic lesions that were easily overlooked with routine CT angiography alone. CONCLUSION: Routine plus targeted CT angiography, while providing superior image quality, did not have much clinical effect; further assessment may be needed.  相似文献   
38.
We present a systematic review of the literature on the prevalence, nature, severity, course, and causes of cognitive deficits in patients with occlusive disease of the carotid artery prior to surgery (if surgery was under discussion). Searches were carried out on Medline and Psychlit from 1980 to 1999 using neurovascular and psychological index terms, and papers and books were checked for further references. Studies describing neuropsychological assessment of groups of patients with carotid obstruction were included. Eighteen studies were found. We extracted from the papers data on study design, demographic characteristics of patients, clinical diagnosis, carotid obstruction, cerebral imaging, time interval between ischemic episode and neuropsychological assessment, neuropsychological asessment procedures, integration and interpretation of test performances, and conclusions of authors. Fourteen studies concluded that there are cognitive deficits both in patients with symptomatic and in those with asymptomatic carotid obstruction; four studies denied cognitive impairment. There were no differences in patient characteristics, study design, or neuropsychological assessment procedures between the 14 studies that found deficits and the 4 that did not. There are indications for a mild, diffuse, detrimental effect of carotid occlusive disease on cognitive functioning. However, methodological problems prevent a definitive conclusion. Further research is needed to confirm these findings and to ascertain the neurovascular risk factors for and the natural course of cognitive impairment in patients with carotid occlusive disease. Received: 12 July 1999/Received in revised form: 10 November 1999/Accepted: 26 January 2000  相似文献   
39.
目的探讨肝素对妊娠中晚期脐动脉血流异常的影响,以便寻找改善脐动脉血流异常的有效治疗方法。方法采用脐动脉血流收缩期最大血流速度(S)与舒张末期血流速度(D)的比值,将脐动脉血流S/D比值大于相应孕周的第95百分位以上的83例妊娠中晚期妇女共85例胎儿(2例双胎)分为研究组(41例孕妇,42例胎儿)和对照组(42例孕妇,43例胎儿)。研究组应用肝素6 250 u+5%葡萄糖500 mL;对照组应用低分子右旋糖酐500 mL,丹参30 mL+10%葡萄糖500 mL。定期复查脐动脉血流S/D比值(每天1次)。结果研究组平均每天脐动脉血流S/D比值下降0.39,对照组平均每天脐动脉血流S/D比值下降0.12,两组结果比较差异具有显著性(t=3.45,P<0.05)。研究组所需治疗时间显著短于对照组(3.5±2.7 vs 7.3±3.1d),两组比较差异具有显著性(t=5.83,P<0.01)。研究组脐动脉血流S/D比值下降率为100%,对照组为68.3%,两组比较差异有统计学意义(χ2=4.12,P<0.05)。结论肝素可显著改善妊娠中晚期脐动脉血流异常,效果显著,疗程缩短,值得推广。  相似文献   
40.
王萍 《海南医学》2008,19(4):4-5
目的探讨颈动脉超声与动态心电图与冠心病的相关性。方法研究对象经CAG分为冠心病组和非冠心病组,超声观察颈动脉IMT及动态心电图试验结果,与CAG结果对照。结果非冠心病组、冠心病组不同分支病变组患者颈动脉IMT和冠状动脉记分随CAG严重程度的增加显著增加(P<0.05H或0.01),颈动脉IMT对冠心病诊断有较高的敏感性、特异性和Kappa值;动态心电图结果对冠心病诊断有较高的敏感性、特意性Kappa值。结论颈动脉超声和动态心电图是冠心病诊断的重要的辅助检查手段。  相似文献   
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