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141.
汽车驾驶员心电多相频谱分析   总被引:2,自引:0,他引:2  
对117例汽车司机应用HBD-1心电多信息诊断仪进行心电多相频谱分析,其功率谱,传递相移,幅度直方图等五项指标总分阳性率明显高于对照组,随着驾车年限的增加,总分阳性率有升高趋势,心电频谱分析对230例冠心病病人阳性检出率84.78%。研究认为汽车司机是易发高血压,冠心病的危险人群,该方法在冠心病的环境流行病学研究中具有重要的临床,亚临床意义。  相似文献   
142.
髂内动脉结扎术是控制妇产科手术中大出血的有效措施。本文收集此类患者21例,行双侧髂内动脉结扎15例,单侧6例,均达到了满意的止血效果。笔者介绍了馆内动脉结扎术的方法和临床应用,以及预防髂内静脉损伤和误扎髂多外动脉的具体措施。着重提出髂内动脉结扎后再局部止血才能完全控制盆腔大出血。  相似文献   
143.
新的钙通道阻滞剂 MC9204 对离体兔动脉环的作用   总被引:5,自引:2,他引:3  
目的:比较MC9204和nifedipine(NIF)的扩血管强度,并观察MC9204是否具有血管选择性作用。方法:采用离体血管张力实验法,观察MC9204和NIF的扩血管作用。结果:MC9204和NIF对KCl、CaCl2和去甲肾上腺素(NE)引起的离体兔动脉环收缩反应均具有显著的拮抗作用,使剂量-效应曲线右移。在NE双相收缩实验中,二药均可显著抑制NE依外Ca2+性收缩反应,而对NE依内Ca2+性收缩反应无抑制作用。结论:MC9204扩血管作用强于NIF,MC9204对肾动脉和肠系膜上动脉的抑制作用强于腹主动脉,具有一定的血管选择性作用,此作用通过抑制细胞外Ca2+的进入而实现。  相似文献   
144.
Background : It is well known that reoperation for recurrent coronary artery disease is more difficult than primary coronary artery bypass grafting. However, it is possible to reduce the morbidity and mortality of reoperation to the same level as the initial procedure with careful surgical technique. Methods : A retrospective study of the first 200 patients who underwent redo coronary bypass grafting was undertaken. Results : In the first 200 cases of redo coronary bypass grafting at St George Hospital, Sydney (August 1986–January 1995), there were five in-hospital deaths (2.5%). There was one case of sternal infection (0.5%), which required surgical debridement, three cases of stroke (1.5%), one case of postoperative bleeding (0.5%), which required a return to theatre and six cases (3%) required mechanical ventilation for more than 24h. The need for major postoperative support (such as intra-aortic balloon pumping/adrenaline infusion) was significantly affected by the degree of urgency and the degree of pre-operative ventricular impairment. Conclusions : The mortality rate of redo coronary artery bypass grafting in this series is similar to that of primary surgery described in other reports.  相似文献   
145.
A quantified evaluation of planar cardiac perfusion scintigrams (the objective of the study), obtained using technetium-99m methoxyisobutylisonitrile (MIBI) was performed on the basis of an analysis of circumferential profile curves, representing the perfusion as seen in three typical projections. The analysis involved the curves obtained both at rest and after stress, and was based on a comparison of their shape (trend) with the normal trend (normative evaluation). The latter was obtained by means of an original method of iterative fitting of individual curves into the database. The base consisted of curves recorded in 53 patients (separately in males and females) with normal perfusion of the left ventricle (group I, the reference group). A group of 90 patients suspected of having coronary artery disease (group II) was subdivided into two subgroups on the basis of coronary arteriography: (a) those with and (b) those without critical stenosis of at least one artery. Profile curves characterising the LV perfusion were obtained at rest and after stress. Defects of perfusion were quantified by comparison of individual curves with the normal trends. By means of multivariate analysis it was demonstrated that vectors of mean values characterising the scintigraphically assessed defects of LV perfusion in the two subgroups of group II differed very significantly (P<10–5). Applying methods of discriminant analysis, a classification of patients from group II was performed into those with probable defects of perfusion and those free of such defects. The sensitivity, specificity and accuracy of diagnosis of coronary ischaemia, based on quantified planar99mTc-MIBI scintigraphy, reached 86%, 87% and 87%, respectively.  相似文献   
146.
Stenting of the carotid artery is usually performed either to prevent an acute neurologic event or to treat episodes of recurrent transient ischemic attacks. Occasionally, it may be performed for other indications. We describe the case of a patient with prior coronary artery bypass grafting using a left internal mammary arterial graft, in addition to left carotid artery to left subclavian artery bypass for symptomatic left subclavian stenosis, who subsequently underwent left common carotid artery stenting to relieve anginal symptoms.  相似文献   
147.
彩色多普勒和磁共振对健康人颅内动脉影像学的比较研究   总被引:1,自引:0,他引:1  
目的通过彩色多普勒和磁共振血管成像对健康人颅内动脉的检测,初步确定其操作规范及衡量标准。方法正常人200例,按照检查方法分为彩色多普勒血流显像(ColourDopplerFlowImaging,CDFI)组及磁共振血管成像(MagneticReso-nanceAngiography,MRA)组。CDFI组观察大脑中动脉(MiddleCerebralArtery,MCA)、椎动脉(VertebralArtery,VA)各段的血流动力学改变和相应点的血流束内径。MRA组检测相应血管对应部位的血管内径。结果同一条血管不同位置的血流速率有差异(P<0.05);同名血管相应位置的血流速率左侧略高于右侧,女组高于男组,但无统计学意义(P>0.05)。按年龄分组,相邻组间无显著性差异,相隔组间有显著性差异。CDFI所测血流束内径较MRA所测血管内径值偏高,且P<0.05,差异有显著性。结论a)应用CDFI能显示MCA,VA走行,可检测血管的血流动力学的改变。b)要提高临床脑血管疾病诊断的准确性,必须有规范的临床操作和可靠的检测指标。c)对血管内径的测量MRA更佳。  相似文献   
148.
目的探讨兔颈动脉粥样硬化斑块中环氧化物酶-2(COX-2)、诱导型前列腺素合成酶-1(mPGES-1)的表达机制及塞来昔布对其表达的影响。方法采用32只雄性新西兰大白兔.其中正常对照组8只(A组),另24只将特制的硅橡胶圈置于兔右侧颈动脉。术后给予1%高胆固醇喂养14d,建立兔颈动脉粥样硬化性狭窄动物模型,将模型兔随机分为颈动脉狭窄无干预组(B组1、小剂量塞来昔布治疗组(15mg/kg,C组),大剂量塞来昔布治疗组(35mg/kg,D组),每组各8只。治疗4周后取双侧颈动脉并分为平等2段,分别行半定量逆转录聚合酶链反应(RT—PCR)及Western blot法测定颈动脉斑块干预后COX-2及mPGES-1的表达。结果与A组比较,B、C、D组颈动脉粥样硬化模型兔的斑块中COX-2及mPGES.1表达增高,差异具有显著性(P〈0.05);与B组比较,C、D组颈动脉斑块的C0X-2及mPGES.1表达显著下调,差异有显著性(P〈0.051。结论在颈动脉粥样硬化斑块的病理过程中炎症反应可能起着主导作用。塞来昔布干预可抑制COX-2及mPGES—1的表达,减缓颈动脉粥样硬化的进展。  相似文献   
149.
Objective To evaluate the use of the saphenous artery as an alternative access for endovascular procedures in the porcine model. Methods Fourteen adult pigs (25-35kg) were used in this study, 3 pigs from an acute study and 11 from chronic studies. A 2-3 cm incision was made and a saphenous artery cutdown was performed in 24 sides. Micropunc ture sets (Boston Scientific) or 18 G puncture needles were used to access the artery. Different sizes of introducers (4-7F) were used to establish endovascular access. Angiographic catheters were then used to confirm if the access was usable. Four saphenous arteries were explanted in the pigs from a chronic study 4 to 28 days after surgical procedure. Results The saphenous artery was very easy to expose and 4-5 F introducer sheaths were able to be inserted to establish access for endovascular procedures in the pigs. The saphenous artery was unable to accomodate an introducer with a size larger than 6 F. Four saphenous arteries were injured when 5 and 6 F introducers were used, but angiographic procedures could still be performed. Morphologic evaluation of the explanted arteries demonstrated occlusion of the saphenous arteries without injury or disruption of the adjacent femoral arteries. Conclusion The saphenous artery can be used as an access site in pigs for angiographic and interventional procedures if the catheter size is less than 6 F. This vessel is easier to access and can preserve the femoral artery for repeat procedures in the future.  相似文献   
150.
目的 探讨骨间后动脉血管变异时前臂背侧皮瓣的切取方法.方法 以骨间后动脉为蒂逆行岛状皮瓣转移修复手部皮肤软组织缺损时,遇到血管变异共9例,采取以骨间后动脉桡侧支为蒂切取逆行岛状前臂背侧皮瓣、以骨间后动脉近端为蒂切取游离骨间后动脉皮瓣、以骨间后动脉穿支为蒂切取游离前臂背侧穿支皮瓣等方法,进行皮瓣转移或移植修复手部创面.结果 9例皮瓣中有8例顺利存活;1例术后2 d皮瓣远端出现肿胀、青紫、小水泡,及时对症处理,5 d后部分皮缘形成干痂,皮瓣颜色恢复正常,脱痂后存活.9例随访3个月至2年,皮瓣质地柔软,弹性好,外形满意.结论 以桡骨间后动脉侧支为蒂的前臂背侧皮瓣逆行转移,以骨间后动脉近端或骨间后动脉穿支为蒂的前臂背侧皮瓣游离移植修复手部创面,是解决骨间后动脉血管变异较理想的方法.  相似文献   
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