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81.
目的探讨内镜联合肝动脉栓塞化疗(transcatheter arterial chemoembolization,TACE)、射频消融(percutaneous radiofrequency ablation,PRAF)治疗肝细胞癌(hepatocellular carcinoma,HCC)合并胆管癌栓的治疗效果。方法回顾总结1999年1月~2005年12月收治的65例肝细胞癌合并胆管癌栓的诊疗情况。结果65例中,均行内镜胆道引流术或EST及取栓,联合TACE,PRAF治疗。本组无手术死亡。癌栓清除率为95.4%(62/65),肿瘤坏死率为96.9%(63/65),1年生存率为60.0%(39/65),3年生存率为38.5%(25/65)。结论内镜联合TACE及PRAF治疗肝细胞癌合并胆管癌栓不失为一种行之有效的微创治疗方法,疗效优于单纯的内镜、TACE及PRAF治疗。  相似文献   
82.
目的 探讨经尿道前列腺汽化电切术(transurethral electrovaporization of the prostate,TUVP)电切深度标识的可行性。方法 回顾性分析616例前列腺增生症临床资料,其中310例术前彩超提示合并前列腺钙化,156例合并膀胱结石,23例合并膀胱肿瘤。TUVP操作过程中,观察到合并前列腺结石和机械操作“打滑现象”,停止电切。结果 全组手术时间30~120min,平均75min。术中验证术前彩超提示合并前列腺钙化的310例前列腺钙化为结石,同时发现其余306例均存在结石。1例术中膀胱穿孔,无尿道直肠瘘和尿道电切综合征发生。325例随访3~6个月,平均4.5月,最大尿流率由6.5~8.5ml/s提高到18~22ml/s,残余尿由70~150ml降至0~10ml,国际前列腺症状评分由19~24.5分降至0~7分。138例膀胱结石和23例膀胱肿瘤无复发。结论 前列腺结石和机械操作“打滑现象”作为TUVP的电切深度标识是切实可行的。  相似文献   
83.
Straight back syndrome (SBS) is a thoracic deformity with absence of upper thoracic spine kyphosis and heart compression. The anatomic abnormity of SBS may raise the difficulty of introcardial operation and increase the complicated risk of intervention performance. Here we report a case of SBS with complicated transseptal puncture during intervention catheter ablation of atrial fibrillation.  相似文献   
84.
介绍一种能提高小丸微波干燥能力,避免小丸干燥开裂、过火等现象,可以提高小丸微波干燥均匀度的装置。  相似文献   
85.
The development of combined microwave‐enhanced/parallel synthesis procedures and their application to the deuteriation of organic compounds via examples of solid‐state hydrogenation is reported. Other labelling procedures, such as solution state catalytic dehalogenations, hydrogenations as well as hydrogen isotope exchange reactions also benefit from the combined technology. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
86.
Background and Objective: Although the empirical characteristics of ArF excimer laser corneal ablation have been well documented, the exact ablation mechanisms are not well understood. The present paper reports a quantitative analysis of corneal ablation plumes using in situ time resolved laser light scattering and Raman spectroscopy. Study Design/Materials and Methods: Bovine corneas were used as the ArF excimer laser ablation targets. Light scattering data were recorded from the ablation plume as a function of height above the tissue surface and as function of delay time with respect to the ablative ArF laser pulse. Results: Raman spectra of the ablation plume allow identification of the particles as water. Mean plume particle diameters are found to decrease with height, while the particle volume fractions are relatively constant. The total volume of plume particles correlates well with the total volume of water in the ablated corneal tissue. Conclusion: The finding of a non-evolving plume composed of water spherules, combined with the excellent agreement between total volume of water in the plume and the content of water in the ablated corneal tissue, support the concept of photodecomposition or “cold ablation” for corneal tissue during ArF excimer laser ablation. © 1995 Wiley-Liss, Inc.  相似文献   
87.
Tissue removal by infrared lasers is accompanied by thermal damage to nonablated tissue. The extent of thermal damage can be controlled by a choice of laser wavelength, irradiance, and exposure duration. The effect of exposure duration has been studied in vivo by using CO2 lasers with pulse widths that vary from 2 microseconds to 50 msec. Pulse widths of 50 msec, typical of a shuttered, continuous-wave CO2 laser, produce damage regions 750 micron wide in normal guinea pig skin; the use of a 2-microseconds-long pulse reduced this damage zone to as little as 50 micron. Using 2-microseconds-long pulses, in vitro studies showed that the minimum zone of thermal damage varied significantly with tissue type. The thermal denaturation of these tissues has been studied and correlated with damage. The effect of denaturation temperature and pulse duration on the width of the damage zone is explained by a simple model.  相似文献   
88.
Dormant Accessory Pathways. Introduction : Recurrence of clinical symptoms after radiofrequency catheter ablation of an accessory atrioventricular pathway (AP) may be due to the late manifestation of an additional AP that was not detected during the initial ablation session. It was the purpose of this study to elucidate the phenomenon of these "dormant" APs.
Methods and Results : Of 1280 consecutive patients who underwent radiofrequency catheter ablation of an AP, 54 patients (4.2 %) developed clinical symptoms postablation, necessitating a repeat ablation session. Recurrence of conduction over the AP targeted al the initial ablation session was found in 45 patients, whereas in the other 9 patients (0.7%) the manifestation of a previously unnoticed AP had caused symptom recurrence. Retrospective analysis of the data from these patients' ablation sessions revealed that the late manifesting AP was ablated at a site clearly different from that of the initially targeted AP, and that the manifestation of conduction over a previously "dormant" AP occurred significantly later than the recovery of a presumably ablated AP. Seven (78%) of the 9 "dormant" APs were concealed, and none exhibited decremental conduction properties.
Conclusion : The incidence of clinical recurrences mediated by the late manifestation of conduction over a previously "dormant" AP is low. The lack of an anatomic vicinity of these predominantly concealed APs with the initially targeted AP and the lack of evidence for their presence during the initial ablation session suggest intermittent conduction as the most likely explanation for their late manifestation.  相似文献   
89.
用微波(频率2450MH_2(、单板天线(含测温装置)功率50W、中央定温60℃,进行狗前列腺热凝术。术后组织学观察,变化可分为三期:①凝固坏死期(0~3天);②炎症反应期(第6~15天);③组织自身修复期(第18~24天)。膀胱尿道造影及大体标本观察,尿道前列腺部明显扩大。提示局部、深部、温控微波热凝术,能有效地破坏前列腺组织,拓宽尿道前列腺部,而毗邻组织不受损伤。  相似文献   
90.
射频消融迷宫术治疗心房纤颤   总被引:3,自引:0,他引:3  
作者采用射频消融迷宫术治疗心房纤颤20例,其中19例合并风湿性二尖瓣病的患者,同时行瓣膜替换术,1例合并房间隔缺损患者进行修复。射频消融的路线采用小板井嘉夫的手术径路。术后16例恢复窦性心律,占80%,未恢复窦性心律的4例,2例为房颤,1例为房扑,另1例为结性心律。射频消融迷宫术耗时短,仅增加钳闭主动脉时间平均20.5分钟,无术后出血的潜在危险。但术后7~10天之内,有18例出现过房颤、房扑、房速等室上性心律失常,可能由于射频消融不均匀,干扰心房的心电活动所致。  相似文献   
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