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41.
葛根素对抗H2O2引起血管平滑肌细胞凋亡及坏死   总被引:13,自引:0,他引:13       下载免费PDF全文
目的:研究葛根素对过氧化氢引起无血清培养的小牛主动脉血管平滑肌细胞凋亡和坏死的影响。方法:通过体外细胞培养,以噻唑兰(MTT)法测定细胞存活率,用流式细胞术检测细胞DNA含量及凋亡细胞百分率;DNA琼脂糖凝胶电泳法观察细胞凋亡过程中DNA断裂程度。结果:H2O2诱导无血清培养的平滑肌细胞凋亡,葛根素可显著降低平滑肌细胞中凋亡细胞百分率,并减少凋亡细胞DNA断裂,同时也减少其引起的平滑肌细胞坏死。结论:葛根素可对抗H2O2引起的无血清培养的血管平滑肌细胞凋凋亡及坏死。  相似文献   
42.
观察7例慢性哮喘病人胸导管引流治疗前后外周血淋巴细胞内 cAMp/cGMP 值的变化。结果发现,慢性哮喘病人外周血淋巴细胞内 cAMP/cGMP 的值较正常人低(P<0.001);胸导管引流治疗后,哮喘病人外周血淋巴细胞内 cAMP/cGMP 值较治疗前升高(P<0.01)。提示,慢性哮喘病人外周血淋巴细胞功能异常、活性增强,这可能是哮喘发病的重要原因之一。胸导管引流引起的免疫抑制作用,一个重要的机理就是影响淋巴细胞内环核苷酸的代谢,而使淋巴细胞的活性降低,这可能也是胸导管引流治疗慢性哮喘的机理之一。  相似文献   
43.
SummaryBackground With increasing frequency, spine surgeons are being asked to provide decompression and stabilization in patients with spinal metastases. While no region of the spine is easily treated, the upper thoracic spine is perhaps the least accessible. Traditional approaches to this region involve either thoracotomy or at least limited sternotomy. The authors present an approach to anterior pathology of the upper thoracic spine that obviates the need for sternotomy.Methods Within the past two years, two patients with cervicothoracic metastases underwent anterior decompression and fusion without sternotomy. In both patients, the bodies of C7, T1, and T2 were removed. While both patients were prepared and draped for sternotomy, each required a neck dissection only. In both patients, left-sided incisions were made along the leading edge of the sternocleidomastoid. The platysma was divided with the overlying skin. With further dissection, the strap muscles were tagged and divided approximately one centimeter above their sternal attachments. The loose areolar tissue of the superior mediastinum was then bluntly dissected. Along the entire length of the incision, the vascular plane medial to the carotid sheath was developed to facilitate exposure of the anterior spine. A Farley-Thompson retractor system was then employed to retract and protect the superior mediastinal structures. With this exposure, corpectomies were carried out using a high speed drill. Fusion was accomplished through insertion of Steinmann pins into the adjacent intact bodies above and below. This was followed by application of methyl methacrylate. Both patients had immediate postoperative stability with preservation of spinal cord function. Both patients subsequently underwent removal of dorsally located tumor with posterior fusion.Conclusions The goal of cancer surgery is to provide for increased functional survival without undue morbidity. The authors feel that when possible, the pain of sternal and clavicular osteotomies should be avoided. The described approach works well in conjunction with a methyl methacrylate/Steinmann pin construct. Because of the intact sternum, the surgeon has a downward angle to access the superior endplate of T3. With adequate soft tissue dissection and retraction as described, however, T3 and perhaps even T4 are easily accessible. While this downward angle would likely not permit an anterior plating procedure, it lends itself nicely to Steinmann pin/methyl methacrylate fusion and spares the patient the pain and potential morbidity of sternotomy.  相似文献   
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目的 总结腔内隔绝术治疗Stanford B型胸主动脉夹层动脉瘤某些特殊情况下近端内漏的治疗方法,比较延伸移植物(cuff)延伸释放法和后撤释放法的价值。方法 2001年以来,stanford B型胸主动脉夹层动脉瘤腔内隔绝术中发生近端内漏6例,分别采用向近端延伸法和后撤法植入cuff封闭内漏。结果 3例采用延伸法,其中1倒采用1枚cuff,1例采用5枚cuff,均完全封闭内漏;1例采用1枚cuff封闭不完全,带漏返回。3例采用后撤法,各用l枚cuff一次性将近端内漏消除。结论 主动脉弓远端或降主动脉近端成角明显时,如腔内隔绝术治疗Stanford B型主动脉夹层动脉瘤术中发生近端内漏,采用后撤法植入cuff是一种效果满意的方法。  相似文献   
47.
胸主动脉夹层动脉瘤腔内隔绝术手术入路的探讨   总被引:3,自引:0,他引:3  
目的 探讨为胸主动脉夹层动脉瘤(TAD)行腔内隔绝术(EVE)选择合适的导入动脉。方法 以彩超,CTA或MRA为检查手段,评估导入动脉(股动脉、髂总动脉、腹主动脉下段等)的直径大小(≥8mm)、有否硬化斑块、狭窄、是否被夹层累及、有否扭曲及其程度,从而选择具体的手术入路。结果 本组37例TAD行EVE术所选择经股动脉手术入路23例、经髂总动脉手术入路14例。未选择经腹主动脉下段手术入路。即时操作成功率为100%。结论 合理的选择导入动脉作为手术入路,是EVE手术治疗TAD顺利完成的要点。  相似文献   
48.
血管内支架移植物治疗胸-腹主动脉瘤   总被引:5,自引:0,他引:5  
目的 评价内支架移植物 (ESG)植入术治疗胸、腹主动脉瘤的有效性和安全性。方法  2 8例胸、腹主动脉夹层动脉瘤 (AD或AAA) ,全麻下行血管内支架移植物治疗 ,其中 5例AD植入TALENT移植物 ,9例植入国产ESG ;7例AAA植入Zenith和TALENT分叉型ESG ,7例植入国产ESG。结果  2 5例动脉假腔及动脉瘤得到有效隔绝。2例AD封堵失败 ;1例AAA移植物遮盖右肾动脉开口 ,术后肾体积缩小 ;1例AAA因多器官衰竭死亡。平均随访 18.5± 15 .1个月( 1~ 5 9个月 ) ,2 5例生活及工作情况良好。结论 ESG植入术可有效治疗StanfordB型AD和肾下AAA ;严格掌握适应证有助于减少并发症  相似文献   
49.
Objective: Reoperative coronary bypass grafting is at high risk. Particularly in redo cases where the patent graft is running near the midline of the sternum, the graft may be exposed to injury by a median sternotomy and subsequent dissection. Whereas, off-pump bypass grafting from the left axillary artery or descending thoracic artery by a left thoracotomy approach is safe for preventing graft damage.Methods: From March 1998 to February 2002, we performed off-pump coronary artery bypass grafting by a left thoracotomy approach in 9 patients. The left axillary artery was used as the inflow vessel in 4 cases, and the descending thoracic, aorta in 5.Results: The radial artery was anastomosed proximally to the axillary artery in 4 cases and the descending thoracic aorta in one case. The saphenous vein graft was anastomosed, proximally to the descending thoracic aorta in 4 cases. Transdiaphragmatic minimally invasive bypass grafting for the right coronary artery was simultaneously performed in 3 cases. Postoperative cardiac events were ventricular arrhythmia in 6 cases and supraventricular arrhythmia in 3 cases. There was no damage to the patent grafts. Postoperative coronary angiography performed, in 8 cases revealed all the grafts to be patent without stenosis. Cardiac symptoms were not found after the operation in any of the cases.Conclusions: These procedures can prevent the injury to patent grafts caused by a median sternotomy, and will be one of the useful strategies for reoperative off-pump coronary artery bypass grafting.  相似文献   
50.
The authors, reviewing the international literature with their clinical experience developed in reconstructive surgery of acetabular defects due to aseptic loosening of acetabular cups, suggest their guidelines to the right use of acetabular reinforcement rings. Received: 8 September 2001/Accepted: 4 November 2001  相似文献   
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