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71.
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   
72.
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   
73.
目的:观察整脊疗法对功能性消化不良患者血浆胃动素(MTL)和血清胃泌素(GAS)含量的影响,并探讨整脊疗法对该病的作用机制。方法:将功能性消化不良60例患者按随机分配原则分为两组,治疗组采用整脊疗法治疗,对照组口服贝络纳治疗,观察血浆胃动素、血清胃泌素含量的变化。结果:整脊疗法能提高MTL水平(P〈0.01),降低GAS(P〈0.05),其作用与贝络纳相仿。结论:通过对功能性消化不良患者血浆胃动素、血清胃泌紊含量变化的观察,整脊疗法可能通过调节脑一肠轴的脊柱前神经节影响胃肠神经系统改变胃肠黏膜分泌MTL和GAS的含量,改善胃肠功能。  相似文献   
74.
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   
75.
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   
76.
主动脉缩窄及主动脉弓离断的电子束CT诊断   总被引:12,自引:0,他引:12  
目的:探讨电子束CT诊断先天性主动脉缩窄和主动脉弓离断的价值。材料和方法:共10例病人,年龄6—18岁,均经手术证实。对所有患儿行EBCT增强扫描,并对图像行三维重建。结果:10例病人术前均得到正确诊断,其中8例为主动脉缩窄,2例为主动脉弓离断。EBCT均显示了全部8例主动脉缩窄及其缩窄的程度、形态,并显示缩窄处与左锁骨下动脉的关系。其中6例(75%)为局限性狭窄,2例(25%)形成中-重度长管状狭窄。合并畸形有:3例合并动脉导管未闭,1例合并室间隔缺损,1例合并肺动脉狭窄,1例合并二尖瓣狭窄,2例同时合并动脉导管未闭和室间隔缺损。2例主动脉弓离断病例,均合并有动脉导管未闭、室间隔缺损和肺动脉狭窄。EBCT均显示升主动脉与降主动脉呈分离状。结论:EBCT作为一种无创性检查方法,对先天性主动脉病变的诊断有重要价值,并能同时显示合并的胸部大血管异常。  相似文献   
77.
There is limited information regarding oral health status and other predictors of oral health‐related quality of life. An association between oral health status and perceived oral health‐related quality of life (OHQOL) might help clinicians motivate patients to prevent oral diseases and improve the outcome of some dental public health programs. This study evaluated the relationship between older persons' OHQOL and their functional dentition, caries, periodontal status, chronic diseases, and some demographic characteristics. A group of 733 low‐income elders (mean age 72.7 ISD=4.71, 55.6% women, 55.1% members of ethnic minority groups in the U.S. and Canada) enrolled in the TEETH clinical trial were interviewed and examined as part of their fifth annual visit for the trial. OHQOL was measured by the Geriatric Oral Health Assessment Index (GOHAI); oral health and occlusal status by clinical exams and the Eichner Index; and demographics via interviews. Elders who completed the four‐year assessment had an average of 21.5 teeth (SD=6.9). with 8.5 occluding pairs (SD=4.6), and 32% with occlusal contacts in all four occluding zones. Stepwise multiple regressions were conducted to predict total GOHAI and its subscores (Physical, Social, and Worry). Functional dentition was a less significant predictor than ethnicity and being foreign‐bom. These variables, together with gender, years since immigrating, number of carious roots, and periodontal status, could predict 32% of the variance in total GOHAI, 24% in Physical, 27% in Social, and 21 % in the Worry subscales. These findings suggest that functional dentition and caries influence older adults' OHQOL, but that ethnicity and immigrant status play a larger role.  相似文献   
78.
胫骨延长术是矫治小儿麻痹后遗症下肢短缩最常见的术式,但如何恢复或改善术后的功能,目前尚无一套系统的程序。本文作者根据自行设计的胫骨延长休后功能康复的临床观察,作较系统地介绍,并就该程序的合理性,进行了讨论与论证。  相似文献   
79.
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   
80.
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   
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