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51.
1. This study was undertaken to evaluate the preventive effects of locally administered argatroban, a competitive inhibitor of thrombin-induced platelet activation, on restenosis after balloon angioplasty. 2. A hydrogel-coated balloon catheter was immersed three times in argatroban/saline solution (1 mg/mL) for 60 s, inflated to a pressure of 606 kPa and left in the rabbit common carotid artery for 1 min. The same procedure was performed, without drug, as a control. The pharmacokinetics of delivered argatroban in the arterial wall were assessed using [14C]-argatroban. Platelet deposition 2h after balloon injury was quantified by fluorescence studies using antiplatelet antibody. Vascular smooth muscle cell (VSMC) proliferation 3 days after balloon injury was assessed by immunohistochemical staining for proliferative cell nuclear antigen (PCNA). In a clinical study, we divided 50 elective patients into two groups: argatroban and control. 3. In the experimental study, the mean quantities of argatroban at 0, 2 and 6 h after deflation wer. 24.63, 0.49 and 0.11 nmol/g wet weight of artery, respectively. Argatroban was undetected 24 h after deflation. Two hours after deflation, argatroban-treated arteries showed less platelet adhesion than saline-treated controls. The mean number of PCNA-positive cells was 16.9 and 43.8% in the argatroban and control groups, respectively (P < 0.01). In the clinical study, the mean late gain loss was 8.2 and 27.3% in the argatroban and control groups, respectively (P < 0.05). The mean late restenosis rate was 11.1 and 41.4% in the argatroban and control groups, respectively (P<0.05). 4. These data suggest that blood coagulation plays a significant role in VSMC proliferation after balloon injury and that locally administered argatroban using hydrogel-coated balloon catheter may prevent post-percutaneous transluminal coronary angioplast. restenosis.  相似文献   
52.
Catheter Ablation Techniques in AVNRT. Radiofrequency catheter ablation has been established as a first-line curative treatment modality in patients with symptomatic AV nodal reentrant tachycardia (AVNRT). The successful sites of stepwise catheter ablation approaches of the so-called fast and slow pathways strongly suggest that AVNRT involves the atrial approaches to the AV node. The typical fast pathway ablation sites are located anterosuperior toward the apex of the triangle of Koch, which also contains the compact AV node, whereas the usual slow pathway ablation sites are located posteroinferior toward the base of the triangle of Koch at a greater distance to the compact AV node and bundle of His. Accordingly, ablation studies with large patient cohorts have demonstrated that fast pathway ablation carries a higher risk of inadvertent complete AV block. Thus, the slow pathway is clearly the primary target site, and fast pathway ablation is rarely necessary. Different approaches for slow pathway ablation have been elaborated: anatomically oriented stepwise techniques, ablation guided by double potentials recorded within the area of the slow pathway insertion, and combined techniques. The modern concept of AVNRT suggests that this arrhythmia involves the highly complex three-dimensional nonuniform anisotropic AV junctional area. Accordingly, mapping and ablation studies demonstrated that the anterior approach is not identical with fast pathway ablation, and the posterior approach is not identical with slow pathway ablation. Therefore, it is essential for interventional electrophysiologists to familiarize themsdves with the anatomic and electrophysiologic details of this complex and variable specialized AV junctional region. In this review, the anatomic and pathophysiologic aspects of the AV junctional area as they relate to interventional therapy are summarized briefly, and the catheter techniques for ablation of the so-called fast and slow AV nodal pathways for the treatment of AVNRT are described.  相似文献   
53.
目的 研究臂丛神经根单发断,2根切断(不同方式联合)及3根切断后对肢体的影响,为治疗臂丛根性撕脱伤寻找更多的潜在移位神经,方法 252只SD大鼠随机分为13组:(1)第1-5组(单根神经根切断组);每组12只大鼠。分别切断C5-8T1各神经根;(2)第6-12组(2根神经根切断组);每组24只大鼠。分别切断相邻及不相邻2根神经根,即C5,6,C6,7,C7,8,C8T1,C5,7,C6,8和C7T  相似文献   
54.
对豚鼠胃肠道各段的研究发现,在胃体、胃底和幽门的粘膜下层内,血管仅由神经纤维束伴行。除小肠粘膜下层可见神经节丛与血管伴行外,在盲肠粘膜下层,亦可见神经节丛与小动、静脉伴行,尤以血管始段及第一分支段最明显。某些神经节丛还发出神经纤维束投射到血管壁上。在结肠和直肠均未见到神经节丛与血管的伴行现象。  相似文献   
55.
56.
Infectious peritonitis complicating suprapubic catheter removal   总被引:1,自引:0,他引:1  
Peritonitis following suprapubic catheter placement may result from inadvertent placement of the drain through the large and small bowel and bladder base. The author describes a case of infectious peritonitis which developed after suprapubic catheter removal. The patient, underwent suprapubic catheter placement after Burch Colposuspension for genuine stress incontinence. The catheter was removed with a full bladder after an uneventful postoperative course, but the patient subsequently developed acute infectious peritonitis due to extravasated urine from the cystostomy site. It was concluded that suprapubic catheters should be removed after the bladder is emptied, to prevent this complication. This may be most important in patients who void without residual prior to epithelialization of the cystostomy site.Editorial Comment: This paper illustrates another complication of suprapubic catheter use. In this case peritonitis developed secondary to infected urine entering the peritoneal cavity after removal of the catheter when the bladder was full. The peritoneum had not been closed at the time of the original Burch procedure. The authors make the point of planning removal when the bladder is empty. Another consideration would be to close the peritoneum when a suprapubic catheter is used.  相似文献   
57.
目的:了解肾上腺素对丁哌卡因肌间沟臂丛神经阻滞的药效学及药动学影响。方法:选择ASA Ⅰ~Ⅱ级肩部或上肢择期手术患者16例,随机分成两组,试验组与对照组各8例,分别用含或不含肾上腺素的0.75%丁哌卡因2mg/kg行肌间沟臂丛阻滞。对比观察两组的临床效果及药代动力学。结果:与对照组比较,试验组阻滞完善时间及镇痛时间延长(P<0.05或0.01)。试验组与对照组Cmax分别为0.8295±0.2893ug/ml和0.8898±0.2572ug/ml,Tmax分别为37.6018±8.3461分钟和29.3156±11.1991分钟(P>0.05)。药代动力学参数t1/2Ka及K_(21)两组间有显著性差异(P<0.05或0.01)。结论:肾上腺素能延长丁哌卡因的阻滞完善时间、镇痛维持时间及吸收半衰期,但对血药浓度无明显影响。  相似文献   
58.
健侧颈7移位治疗臂丛神经根性撕脱伤手术分第一阶段(健侧颈7移位到移植神经),第二阶段(移植神经另一端移植修复患侧神经),二次手术间隔多少时间才能获得最好的神经再生?选用SD大鼠及健侧颈7移位的实验模型,按二次手术间隔时间的不同(0、1、2、3、4、8、16周)分成7组,在第二次术后12周,进行电生理测定肌张力恢复率及组织切片的形态学观察,结果证实二次手术最佳间隔时间为4~8周.此结果可提供临床参考.  相似文献   
59.
Joaquin Albarran was an extraordinary late 19th century urologist. His early career was in the field of microbiology and histopathology in Paris at a time of great medical developments and innovations. His later contributions to urology included the Albarran lever, Albarrans sign, Albarran-Ormond syndrome and seminal works on testicular and renal tumors. He also wrote treatizes on the pathophysiology of acute urinary retention, nephritis and calculus ureteric obstruction. He died at the young age of 52 from the effects of tuberculosis and in this same year was nominated for the Nobel prize in medicine.  相似文献   
60.
The use of directional coronary atherectomy (DCA) in current practice has been limited. The SilverHawk System is a newly developed plaque excision device that aims to overcome the drawbacks of prior DCA platforms. The device was evaluated in a porcine coronary model and in a series of patients. Procedural variables along with outcomes were reviewed. Quantitative angiography (QCA) was performed and excised tissue fragments were weighed and examined histologically. In porcine cases, pretreatment MLD increased from 0.51 +/- 0.26 to 2.36 +/- 0.59 mm postdebulking and 19.9 +/- 7.6 mg of tissue was retrieved. In human cases, pretreatment MLD increased from 0.8 +/- 0.4 to 2.2 +/- 0.5 mm postdebulking and 15.2 +/- 7.8 mg of tissue was retrieved without complications. These data show that the SilverHawk System may offer significant utility in treating a wide variety of complex coronary lesions.  相似文献   
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