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101.
102.
Nenad Ilijevski Petar Otasevic Bratislav Milosavljevic Ljiljana Jovovic Dragan Sagic Djordje Radak 《Surgical Practice》2007,11(2):54-59
Objective: To analyse the incidence, clinical presentation, and outcome of heart insufficiency in patients with chronic arteriovenous fistulas (AVF). Methodology: From 1991 to 2000 we treated 49 patients with traumatic AVF. The present study included 19 patients with AVF present for 6 months or longer, as it was presumed that these AVF will have an impact on cardiac overload. There were 16 male and three female patients with a mean age of 36 years (17–59). The time from injury to admission varied from 6 months to 33 years. Cardiological examination checked for dyspnoea and palpitation. ECG, chest X‐ray and ECHO‐cardiography were also performed. All AVF were deleted, magistral vessels reconstructed, non‐magistral obliterated, either surgically or by percutaneous embolization. Results: Mean follow up was 44.2 months (3–93). Serious heart insufficiency was seen in two patients only, with AVF in the subclavial vessels. Both suffered from serious heart disease prior to the therapeutic procedures that resulted in iatrogenic AVF, so it was difficult to connect heart insufficiency to the AVF alone. Despite surgical closure of AVF and intensive medical treatment, signs of heart insufficiency remained in both patients. Signs of cardiac overload were seen in six patients with long‐standing AVF in major vessels. Except for one patient who refused surgical closure of femoral AVF, the remaining five were symptom free for cardiac overload during the follow‐up period. Conclusion: In our series, heart insufficiency was an infrequent complication in long‐standing AVF, even when major vessels were involved. 相似文献
103.
P. Hendrik Pretorius Michael A. King Howard C. Gifford Seth T. Dahlberg Frederick Spencer Ellen Simon Jason Rashkin Naomi Botkin William Berndt Manoj V. Narayanan Jeffrey A. Leppo 《Journal of nuclear cardiology》2005,12(3):284-293
BACKGROUND: Past receiver operating characteristic (ROC) studies have demonstrated that single photon emission computed tomography (SPECT) perfusion imaging by use of iterative reconstruction with combined compensation for attenuation, scatter, and detector response leads to higher area under the ROC curve (A(z)) values for detection of coronary artery disease (CAD) in comparison to the use of filtered backprojection (FBP) with no compensations. A new ROC study was conducted to investigate whether this improvement still holds for iterative reconstruction when observers have available all of the imaging information normally presented to clinical interpreters when reading FBP SPECT perfusion slices. METHODS AND RESULTS: A total of 87 patient studies including 50 patients referred for angiography and 37 patients with a lower than 5% likelihood for CAD were included in the ROC study. The images from the two methods were read by 4 cardiology fellows and 3 attending nuclear cardiologists. Presented for the FBP readings were the short-axis, horizontal long-axis, and vertical long-axis slices for both the stress and rest images; cine images of both the stress and rest projection data; cine images of selected cardiac-gated slices; the CEQUAL-generated stress and rest polar maps; and an indication of patient gender. This was compared with reading solely the iterative reconstructed stress slices with combined compensation for attenuation, scatter, and resolution. With A(z) as the criterion, a 2-way analysis of variance showed a significant improvement in detection accuracy for CAD for the 7 observers (P = .018) for iterative reconstruction with combined compensation (A(z) of 0.895 +/- 0.016) over FBP even with the additional imaging information provided to the observers when scoring the FBP slices (A(z) of 0.869 +/- 0.030). When the groups of 3 attending physicians or 4 cardiology fellows were compared separately, the iterative technique was not statistically significantly better; however, the A(z) for each of the 7 observers individually was larger for iterative reconstruction than for FBP. Compared with results from our previous studies, the additional imaging information did increase the diagnostic accuracy of FBP for CAD but not enough to undo the statistically significantly higher diagnostic accuracy of iterative reconstruction with combined compensation. CONCLUSIONS: We have determined through an ROC investigation that included two classes of observers (experienced attending physicians and cardiology fellows in training) that iterative reconstruction with combined compensation provides statistically significantly better detection accuracy (larger A(z)) for CAD than FBP reconstructions even when the FBP studies were read with all of the extra clinical nuclear imaging information normally available. 相似文献
104.
目的 研究败血性急性肺损伤的动物模型,并探讨其在急性肺损伤研究中的意义。方法 用盲肠结扎穿刺(CLP)法的豚鼠急性肺损伤模型,结合动脉血气分析、外周血白细胞计数、肺湿重/干重比值(W/D)及肺组织病理观察。结果 CLP模型中动物的症状和表现缓慢出现,逐渐恶化.最后导致败血性休克,于2d左右出现大量死亡。结论 用盲肠结扎穿刺的方法制作豚鼠急性肺损伤动物模型较大鼠内毒素性休克,表现更类似于人类的肠源性肺损伤,且症状缓慢发生,逐渐恶化,有利于观察和进行各种干预。 相似文献
105.
大鼠移植胰腺冷缺血再灌注后细胞凋亡的变化 总被引:2,自引:0,他引:2
目的 探讨移植胰腺冷缺血再灌注后胰腺细胞凋亡的变化过程。方法 6 5只SD大鼠随机分成 7组 :假手术组 ,冷缺血 2h组 ,冷缺血 2h再灌注 1、3、6、9、12h组。通过HE染色后光镜及电镜观察各组的胰腺组织的病理变化 ;采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测凋亡细胞的分布及计数。结果 胰腺移植后早期即可观察到细胞凋亡的典型改变 ,胰腺冷缺血再灌注后发生凋亡的高峰期为再灌注后 3h[AI为 (9.4 6± 2 .91) % ,P <0 .0 1) ,再灌注 6h较 3小时细胞凋亡有所减少 [AI为 (5 .74± 1.6 6 ) % ,P <0 .0 1],再灌注 9h及 12h细胞凋亡进一步减少 [AI分别为 (3.6 0± 1.6 4 ) %及 (3.2 6± 1.35 ) % ,P <0 .0 5 ]。结论 细胞凋亡是胰腺移植后的早期事件 ,移植胰腺冷缺血再灌注后早期主要的死亡方式是凋亡 ;移植胰腺冷缺血再灌注后的凋亡高峰发生在再灌注后 3h。 相似文献
106.
Objective Reduction ascending aortoplasty is an alternative procdure to the replacement of the ascending aorts in case of ascending aorta dilation. However,its applicabikity is still under debate.This retrospective study was designed to evaluuate the midterm follow-up of unsupported ascending reduction aortoplasty for of the ascending aorta in petients with aortic valve dis- ease.Methods From October ,1996 to April,2007, a total of 54 patients with aortic valve disease and dilatation of the ascending aorta underwent unsupported reduction aortoplasty in combination with aortic valve replacement at our institution The diameter of the ascending aorta was measyred before and early after sugery and then later between 13 and 96 menths [mean (23 ±16)months] posto- perativeiy using echocardiography.Results Two patients were dead with thean overall perioperative mortality rate was of 3.7%. The reduction aortoplasty decreased the diameter of the aorta from (45.77±6.02) mm p~eope~afive]y to (34.67 ~4.81) mm early after surgery (P<0.01). During follow-up, the diameter d aorta increased from (34.67±4.81) mm early after surgery to (37.65± 6.35) mm after a mean follow-up of (23±16) months (P<0.01), including the diameters are greater than > 45 mm within 5 pa- tients. Aortic stenosis and an early postoperative diameter greater than 40 mm m'e independent risk factors for redilatation. Conchusion Because of the unsatisfied midterm follow-up redilation of unsupported reduction aortoplasty for dilation of the ascending aorta with aortic valve disease, this group of patients needs continued intimate fallow-up or even reoperation. The patients of stenosis is the surtable indication for RAA, and it is necessary to reduce the diameter of aorta to be lees than 40 mm to prevent redilation. 相似文献
107.
目的 评价控制性降压是否增加脊髓对牵拉损伤的易感性。材料与方法健康成年杂种犬6只,随机分为常压和控制性降压脊髓牵拉损伤组。观察常压及控制性降压水平下相同程度牵拉损伤后脊髓血流(SCBF)、体感诱发电位(SEP)、神经源性运动诱发电位(NMEP)改变的差异。结果 外周血有创动脉压(MABP)平均下降幅度为40.5%。经SSPS统计软件独立样本t检验,不同牵拉水平下,常压组及低压组的SCBF(%)、SEP波幅(Asep)(%)及NMEP波幅(%)无显著差异。结论 尼卡地平控制性降压不增加脊髓对牵拉损伤的易感性。 相似文献
108.
109.
[目的]研究膝以下严重开放性创伤的修复。[方法]自1995年3月~2005年3月收治膝以下严重开放性损伤153例,Ⅰ期修复106例,Ⅱ期修复47例,7种内固定方法,11种皮瓣修复方法。[结果]153例中随访132例,时间6个月~5年,平均17个月,术后功能优良率85.7%,皮瓣成活率良好。皮瓣局部坏死25例,骨不连4例,慢性感染8例,骨髓炎3例。[结论]改进的腓肠神经营养血管皮瓣和皮瓣桥手术扩大了皮瓣的应用范围,减少了并发症的发生。本研究为膝以下严重开放性损伤的修复提供了良好的方法;熟练的显微外科技术和各种组织瓣的合理应用是修复成功的关键。 相似文献
110.
目的研究骨髓基质细胞(BMSCs)移植对大鼠局灶性脑损伤血管生成的影响,探讨BMSCs移植修复大鼠脑损伤的机制。方法制备大鼠局灶性脑损伤动物模型,进行BMSCs移植,通过免疫组织化学、电镜等观察移植局部内皮细胞及微循环的变化。结果BMSCs移植后,局部凝血因子FⅧ染色阳性细胞数增加,染色加深,出现血管样结构;局部微血管内膜较光滑,内皮细胞间可见紧密连接,细胞核形态较规则,基底膜较完整,微血管管腔受压缓解。结论BMSCs移植促进损伤区周围内皮细胞增殖和新生血管形成。损伤区局部微循环得以改善进而修复脑损伤。 相似文献