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61.
淫羊藿总黄酮对肾上腺素β_1受体的特异性阻断作用   总被引:2,自引:0,他引:2  
为探讨淫羊藿总黄酮(TFE)对肾上腺素受体的作用,本实验用离体兔心房肌、主动脉及豚鼠气管观察了TFE对肾上腺素全体的作用,结果TFE(0.13g/L)抑制心房肌肌力和频率,并使异丙肾上腺素(ISO)对心房肌正性频率作用的量效曲线平行右移,但无钙拮抗作用及M受体激动效应,且不影响ISO对豚鼠气管条的负性肌力作用及去甲肾上腺囊(NE)对兔主动脉条的收缩作用。提示TFE选择性阻断肾上腺素β_1受体。  相似文献   
62.
本文对6例慢性夹层动脉瘤的MR所见进行分析。对真腔、假腔、“双腔主动脉”、左室形态和信号对比进行了描述。强调MR非侵袭性检查的重要意义。  相似文献   
63.
本文对10例先天性畸形心脏的房室瓣骑跨进行形态分析,其中7例为三尖瓣骑跨,2例为二尖瓣骑跨和1例为两侧房室瓣均有骑跨。9例为完全性骑跨和1例为不完全性骑跨。除去瓣骑跨外,本文1例还伴有房室瓣的瓣裂、降落伞形、囊状副瓣、异位乳头肌和异常腱索等畸形.  相似文献   
64.
Two hundred aneurysms of the abdominal aorta were treated surgically from 1980 to 1987 by the same surgeon. There were 187 men and 13 women whose mean age was 66.1 years. Nine patients were 80-years-old or more. Eighty-seven percent of patients had preoperative risk factors, 30% of which were coronary artery disease. The operative approach was through a transverse laparotomy in 188 patients compared to 11 midline incisions and one lumbotomy. An aortoaortic tube was inserted in 87 patients, a bifurcated prosthesis in 99, and a tube bypass in 14. Five patients (2.5%) died within the 30 day perioperative period. Death was due to colonic necrosis, right heart chamber thrombosis, renal failure after repeat operation for acute lower limb ischemia, and myocardial infarction associated with renal and respiratory failure. The morbidity rate was 15.7% (31 patients) and included seven neurologic accidents, four respiratory complications, five ischemic events of the lower limbs requiring reoperation and one amputation, four cardiac complications, two renal failures, one reversible colonic ischemia, one revision for incomplete hemostasis, one phlebitis, one sliding syndrome, and five minor infections or cutaneous complications. Mean duration of hospital stay was 10.9 days. These results confirm that direct operation on aortic aneurysms can be performed in patients from all age groups and even with associated diseases. A rapid, simple technique based on a transverse approach, minimal dissection and insertion of aortoaortic tubes, whenever feasible, appears to reduce combined mortality-morbidity.Presented at the Annual Meeting of the Societé de Chirurgie Vasculaire de Langue Française, May 20–21, 1988, La Grande Motte, France.  相似文献   
65.
本文报告1972年8月至1987年8月我院85例风湿性二尖瓣(犭央)窄或伴有轻度关闭不全病人的外科手术疗效。80例行闭式扩张术,5例行直视扩张术。贵州地区病人体型较小,瓣膜损害较重。瓣口扩张2.8~3.5cm,较一般要求偏小。手术后近期疗效较好。  相似文献   
66.
67.
Prosthetic valve endocarditis (PVE) caused by Candida species is associated with high morbidity and mortality. A combination of surgical resection and antifungal drug therapy is the golden standard for treatment, yet surgical intervention is not possible in all cases of Candida PVE. We report a case of PVE due to Candida albicans cured by medical treatment alone. This case suggests that, in some instances, Candida PVE can be managed medically with antifungal therapy. Such a conservative approach should be applied with caution and necessitates very close follow-up on a long-term basis.  相似文献   
68.
Objective To analyze the risk factors of the postoperative mid- and long-term aortic valvular regurgitation after ROSS procedure(pulmanary valve homograft transplantation). Methods Between March 1998 and July 2007,47 patients[25male, 22 female, mean age (13.31±5.79) years, ronge 1-34 years] with aortic valvular disease underwent the Ross procedure at our insti tution. There were 6 patients suffering fron rheumatic heart disease and 41 patients suffering from congenital heart disease. The aver age aortic blood flow velocity was (4.67±3.47) m/s, the average pressure gradient across aortic valve (88.26±58.06)mm Hg, LVEDD (45.53 ±10.78) mm, EF 0.69±0.08. All the patients were followed up in out-patient departement by ultrasonic cardio gram. Multiple logistic regression analysis was performed to find out the risk factors of the postive aortic valvular regurgitation. Results There was no poetoperative death in hospital. The mean follow-up periods was (36.15±22.1) months, rasnge from 12 to 110 months and none long-dated death. Compared with the data recorded in hospital, the diamenters of the aortic sinus and aortic annu lus enlarged significantly, respectively from (26.16±5.10) mm to (32.37±6.84) tam and from (19.41 ~3.98) mm to (23.45± 5.86) mm. The average flow velocity d the homograft (new aortic valve) was(1.39±0.48) m/s, graclient pressure (8.17+6.16) mm Hg. Mild aortic regurgitstion was present in 5 patients (10.6%), moderate aortic tegmgitafion in 2 pmieats (4.3%) and aevere aortic regurgitation in 1 petient (2.1%). The rate of free from regurgitation was 82.9%. Multiple logistic analyses identified the per esence of bicuspid aortic valve, enlargement of aortic annulus and age above 14 years as the risk factors for posterative aortic regurg itation. Conclusion The Ross procedure is a safe and effective procedure with good clinical results in mid-and long-term follow-up. However, the presence of bicuspid aortic valve, enlargement of aortic annulus and age above 14 years preoperatively were identified as the risk factors for postoperative aortic regurgitation.  相似文献   
69.
We describe a case of successful combined repair of the aortic and mitral valves for an indication of active infective endocarditis involving both valves. Mitral valve repair was achieved by vegetation debridement, fixation of the anterior mitral commissure, resection and suturing of the posterior mitral leaflet, and posterior annuloplasty with autologous pericardium. Aortic valve repair was achieved by vegetectomy and commissural plication. Postoperative clinical course was without signs of recurrent infection, and echocardiogram demonstrated mitral valve competence with trivial aortic regurgitation. We concluded that simultaneous valve repair is a viable option in the context of active endocarditis.  相似文献   
70.
黏膜瓣式食管胃吻合术抗反流的食管动力学研究   总被引:5,自引:0,他引:5  
目的寻找一种实用有效的抗反流食管胃吻合术式。方法将食管癌和贲门癌患者464例随机分为黏膜瓣式食管胃吻合术组(A组,175例)、器械食管胃吻合术组(B组,151例)和单纯手工缝合食管胃一层吻合术组(C组,138例)。应用同位素测定胃食管反流指数和24h监测pH值,进行3组间的食管运动功能比较。结果同位素测定胃食管反流指数显示,A组反流阳性率为0,B组为33.3%,C组为6.7%。食管运动功能及24h监测pH显示,A组检测各项指标均接近正常值,B、C组与正常值比较,差异具有统计学意义(P<0.05)。结论黏膜瓣式食管胃吻合术式具有优异的抗反流功能,并能有效地防止食管癌、贲门癌术后反流性食管炎的发生。  相似文献   
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