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41.
尽管基因治疗在实验研究方面已做了大量的工作 ,但实际上临床治疗成功的尚不多。现复习这一领域的近期文献 ,并讨论基因治疗的一些限制和潜在的问题 ,强调在心脏外科作基因治疗临床试验之前必须提请考虑的问题和规则。 相似文献
42.
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
43.
目的:分析阵发性室上性心动过速患者行射频消融术(RFCA)后复发的原因,探讨降低RFCA复发的方法。方法:128例阵发性室上性心动过速患者,行RFCA治疗,术后每3-6个月随访1次,随访4-70个月。结果:128例患者中,复发10例,总复发率7.81%,其中房室结折返性心运过速复发率为7.89%,左侧房室旁路介导心运过速复发率5.56%,右侧旁路介导心动过速复发率16.67%。行射频消融术前70例患者中复发率11.43%,后58例复发率3.45%。结论:精确的靶点标测、熟练的操作技巧以及消融方式的正确运用是降低RFCA复发率的关键。 相似文献
44.
完全型房室间隔缺损合并法洛四联症心内矫正术 总被引:2,自引:2,他引:0
目的总结心内矫正术治疗完全型房室间隔缺损合并法洛四联症(CAVSD-TOF)的经验. 方法从1985年1月至2002年5月,共行CAVSD-TOF心内矫正术12例,年龄6~16岁(11.1±2.8岁),采用右心房、右心室纵切口,前7例采用三片法补片,后5例用二片法补片修补房室间隔缺损,左侧房室瓣裂隙采用间断缝合,右心室流出道用跨瓣补片加宽. 结果术后早期死亡4例,前7例死亡3例,后5例死亡1例,死亡原因为严重低心排血量3例,灌注肺1例.长期随访6例,随访时间3个月至13.5年,无任何症状,NYHA心功能Ⅰ级或Ⅱ级. 结论 CAVSD-TOF采用右心房、右心室纵切口,二片法补片修补房室间隔缺损,常规间断缝合左侧房室瓣裂隙,跨瓣补片加宽右心室流出道能取得较良好的效果. 相似文献
45.
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
46.
黄震华 《中国新药与临床杂志》2005,24(10):829-832
心肌钠钙交换在调节心肌细胞内外钠、钙平衡中发挥重要作用。钠钙交换分为前向型和逆向型2种。在心力衰竭、心肌缺血、心肌再灌注等病理情况下,通过钠钙交换器的离子交换可产生致心律失常性的一过性内向电子流,引起延迟后除极和非折返激动型的室性心动过速。钠钙交换器抑制药在预防这些病理情况下的心律失常具有潜在的作用。 相似文献
47.
48.
小儿病毒性心肌炎181例,其中暴发性及心源性休克型8例。其主要特点是:心脏增大(43.4%),心律失常(93.9%),其中早搏最多见(59.9%);传导阻滞(15.5%)。作者认为应强调对Ⅱ°-Ⅱ型以上传导阻滞病情严重应给激素及临时起搏器抢救治疗;心电轴异常(35.7%),亦是心肌炎的重要心电图改变之一。 相似文献
49.
H. Inaba M.D. J. Sato H. Uchida M. Sakurada T. Ohwada T. Mizuguchi 《Acta anaesthesiologica Scandinavica》1988,32(5):374-378
Fluctuating PEEP (F-PEEP) is a newly developed PEEP in which end-expiratory pressure (EEP) is periodically changed within a certain range. In a dog model with unilateral lung injury induced by the introduction of hydrochloric acid, F-PEEP in which the EEP was periodically changed from 0.5 to 1.5 kPa at periods of 6 min, and conventional PEEP (C-PEEP) with an optimized EEP of 1.0 kPa, were each applied for 30 min. F-PEEP produced a significantly greater improvement of PaO2 and intrapulmonary shunt (QS/QT) than C-PEEP, and at the low EEP phase, the greatest improvement accompanied by an increased dynamic compliance and a large cardiac output was obtained. These results suggest that F-PEEP provides a useful mode of artificial ventilation for the treatment of unilateral lung injury. 相似文献
50.
Analysis of reflex activity in cardiac sympathetic nerve induced by myelinated phrenic nerve afferents 总被引:2,自引:0,他引:2
Electrical stimulation of the phrenic nerve afferents evoked excitatory responses in the right inferior cardiac sympathetic nerve in chloralose-anaesthetized cats. The reflex was recorded in intact and spinal cats. The latency and threshold of the volley recorded from the phrenic nerve as well as of the cord dorsum potentials evoked by electrical stimulation of the phrenic nerve indicated that group III afferents were responsible for this reflex. The phrenicocardiac sympathetic reflex recorded in intact cats was followed by a silent period. The maximum amplitude of the reflex discharges was 800 microV, the latency was 83 ms and the central transmission time 53 ms. Duration of the silent period lasted up to 0.83 s. In spinal cats the reflex was recorded 5.5-8 h after spinalization. The maximum amplitude of the spinal reflex discharges ranged from 22 to 91 microV and the latency from 36 to 66 ms. 相似文献