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91.
W. Rouslin R.S. Cubicciotti W.D. Edwards M.A. Matlib D.R. Wilson B.B. Hamrell A. Schwartz 《Journal of molecular and cellular cardiology》1979,11(1):91-99
Right ventricular hypertrophy was produced by placing a spiral Monel metal clip around the pulmonary trunks of rabbits causing a sustained 67% occlusion of the vessel. The operation produced a doubling of right ventricular weight, by 13 days post-surgery, which persisted throughout the post-operative period studied (13 to 84 days); only a slight increase in left ventricular free wall weight was observed. Isolated mitochondria exhibited region-specific changes with time in state 3 Qo2. Thirteen days after operation, the state 3 Qo2 of right ventricular mitochondria was depressed to about 85% of controls. Thereafter, respiration increased fairly sharply, peaking at just above control values by 40 days post-operation. Finally, it declined abruptly to about 70% of controls by 84 days. A very different pattern of change was observed when left ventricular mitochondrial respiratory activities were examined. Thirteen days after the operation, state 3 Qo2 was elevated somewhat above controls. Thereafter, it declined linearly and gradually, dropping to about 85% of controls by 84 days. 相似文献
92.
《Brain stimulation》2021,14(6):1489-1497
BackgroundThe electrode placement and pulse width for electroconvulsive therapy (ECT) are important treatment parameters associated with ECT related retrograde memory side-effects. Modification of these parameters with right unilateral (RUL) ECT may have utility for further reducing these side-effects.ObjectiveThis study explored use of the frontoparietal (FP) placement for reducing retrograde memory side effects with ECT. We hypothesised that superior retrograde memory outcomes would occur with FP compared to temporoparietal (TP) placement and with ultrabrief (UB: 0.3 ms) compared to brief pulse (BP: 1.0 ms) width ECT.MethodsIn this randomised cross-over, double-blinded study, participants received a single treatment of BP TP, BP FP, UB TP and UB FP ECT. Neuropsychological testing was conducted prior to and immediately following each treatment. Computational modelling was conducted to explore associations between E-fields in regions-of-interest associated with memory.ResultsNine participants completed the study. The FP placement was not superior to TP for retrograde memory outcomes. For both electrode placements UB pulse width was associated with significantly better visual retrograde memory compared to BP (p < .05). With TP ECT, higher E-fields in regions-of-interest were significantly associated with greater visual retrograde memory side-effects (hippocampi: r = −0.77, p = .04; inferior frontal gyri: r = −0.92, p < .01; middle frontal gyri: r = −0.84, p = .02).ConclusionsModification of pulse-width had greater effects than electrode placement for reducing retrograde memory side-effects with RUL ECT. Preliminary findings suggested that higher E-fields may be associated with greater cognitive side-effects with ECT. 相似文献
93.
Sabina Vasaturo David E. Ploeg Guadalupe Buitrago Katja Zeppenfeld Maud Veselic-Charvat Lucia J.M. Kroft 《Korean journal of radiology》2015,16(3):668-672
A 53-year-old woman was referred for ventricular fibrillation with resuscitation. A CT-angiography showed signs of a right ventricular enlargement without obvious cause. A cardiac MRI demonstrated a dilated and hypokinetic right ventricle with extensive late gadolinium enhancement. Arrhythmogenic right ventricular dysplasia (ARVD) was suspected according to the "revised ARVD task force criteria". An endomyocardial biopsy was inconclusive. The patient developed purulent pericarditis after epicardial ablation therapy and died of toxic shock syndrome. The post-mortem pathologic examination demonstrated sarcoidosis involving the heart, lungs, and thyroid gland. 相似文献
94.
Chieh-Ju Chao Dawn E. Jaroszewski Preetham N. Kumar MennatAllah M. Ewais Christopher P. Appleton Farouk Mookadam Michael B. Gotway Tasneem Z. Naqvi 《American journal of surgery》2015,210(6):1118-1125
Background
Cardiac compression in pectus excavatum (PE) deformity and effect of PE surgery on cardiac function in adults have been debated. We examined the effect of PE correction on right heart size and cardiac output.Methods
A retrospective evaluation was performed of 168 adult patients who underwent a modified Nuss PE repair with intraoperative transesophageal echocardiography from 2011 to 2014. Seventeen patients with prior PE repair undergoing bar removal acted as controls.Results
Mean age was 33.0 years (range, 18 to 71 years). There was an increase in right atrium (15.1%), tricuspid annulus (10.9%), and right ventricular outflow tract (6.1%) size after surgery (all P < .0001). Right ventricular cardiac output measured in a subset of 42 patients improved by 38%. No change in chamber size or cardiac output occurred before and after bar removal surgery in the control group.Conclusions
Surgical correction of PE deformity caused a significant improvement in right heart chamber size and cardiac output. 相似文献95.
On crime scenes, whole set of the ten digit fingerprints are rarely found and usually chance prints in the form of single digit fingerprint are encountered. Determination of hand (Right or left) can be of vital importance to reduce the burden on the investigator and may thereby aid in fixation of absolute identity of the donor. In the present investigation, 500 randomly selected and bilateral rolled fingerprints of 250 healthy, consenting adult subjects of a central Indian (Marathi) population with whorl patterns were examined to determine the hand. It was found that by studying various parameters like; slope of apex ridges (towards right, left or absent), rotation of innermost ridges (either clockwise, anti-clockwise or absent), angle formed at both sides of core, position of the perpendicular bisector on the delta line (with respect to core), ridge tracing (outer, inner or meeting), higher ridge count, angle between deltas and core (at deltas), direction of the pattern (tilting/inclination) and distance between the deltas & the core; it is possible to successfully determine the hand of the print. Applying chi-square test, the results were found to be statistically significant at p < 0.01 levels. 相似文献
96.
Banding the Right Ventricular Assist Device Outflow Conduit: Is It Really Necessary With Current Devices? 下载免费PDF全文
Casey Lo Shaun Gregory Michael Stevens Deirdre Murphy Silvana Marasco 《Artificial organs》2015,39(12):1055-1061
Implantable left ventricular assist devices (LVADs) have been adapted clinically for right‐sided mechanical circulatory support (RVAD). Previous studies on RVAD support have established the benefits of outflow cannula restriction and rotational speed reduction, and recent literature has focused on assessing either the degree of outflow cannula restriction required to simulate left‐sided afterload, or the limitation of RVAD rotational speeds. Anecdotally, the utility of outflow cannula restriction has been questioned, with suggestion that banding may be unnecessary and may be replaced simply by varying the outflow conduit length. Furthermore, many patients have a high pulmonary vascular resistance (PVR) at the time of ventricular assist device (VAD) insertion that reduces with pulmonary vascular bed remodeling. It is therefore important to assess the potential changes in flow through an RVAD as PVR changes. In this in vitro study, we observed the use of dual HeartWare HVAD devices (HeartWare Inc., Framingham, MA, USA) in biventricular support (BiVAD) configuration. We assessed the pumps' ability to maintain hemodynamic stability with and without banding; and with varying outflow cannulae length (20, 40, and 60 cm). Increased length of the outflow conduit was found to produce significantly increased afterload to the device, but this was not found to be necessary to maintain the device within the manufacturer's recommended operational parameters under a simulated normal physiological setting of mild and severe right ventricular (RV) failure. We hypothesize that 40 cm of outflow conduit, laid down along the diaphragm and then up over the RV to reach the pulmonary trunk, will generate sufficient resistance to maintain normal pump function. 相似文献
97.
目的探讨左右两侧大脑半球急性脑梗死的临床特点。方法回顾性分析282例急性脑梗死患者,按照梗死部位分为左侧大脑半球脑梗死组152例和右侧大脑半球脑梗死组130例,分别对2组患者临床资料进行比较。结果左侧脑梗死组的发病率、入院时NIHSS评分和GCS评分、病死率高于右侧脑梗死组,差异有统计学意义(P0.05)。左侧大脑中动脉支配区脑梗死发病率高于右侧大脑中动脉支配区脑梗死,差异有统计学意义(P0.05)。结论左侧大脑半球急性脑梗死发病率高于右侧,且病情重、病死率高,提示不同侧大脑半球脑梗死的临床特点存在差异。 相似文献
98.
目的 评价右半肝阻断技术结合陈氏绕肝双悬吊法在右后叶肝肿瘤切除术中的应用价值.方法 2011年1月至2015年1月,在37例解剖性肝脏右后叶切除术中应用持续右半肝及陈氏绕肝双悬吊法辅助肝切除.右后叶肝肿瘤行右后叶切除时,采取持续右半肝阻断技术并结合陈氏绕肝双悬吊法经下腔静脉右侧放置2根提肝带,离断肝实质的过程中通过牵拉提肝带辅助肝切除.结果 全组共37例肝右后叶肿瘤病人行肝右后叶肿瘤切除术.术中均成功分离出右半肝肝蒂和右后叶肝蒂,游离右肝后均成功放置绕肝提拉带,断肝时行右半肝持续肝门阻断,术中无胆管损伤、肝短静脉、肝右静脉撕裂和大出血等相关操作并发症.肝实质离断时间17~28 min,阻断时间约20~30min,术中出血量60~330 ml.术后第1天丙氨酸转氨酶(ALT) 183~352 U/L,生化指标均在1周内恢复正常,无围手术期死亡.结论 右半肝持续阻断结合陈氏绕肝双悬吊法有助于减少右后叶肝切除术中出血量以及改善手术野,缩短肝实质离断时间,减轻肝脏缺血再灌注损伤,其操作简单、使用安全、适用范围广泛. 相似文献
99.
右心室不同部位起搏的血流动力学比较 总被引:1,自引:0,他引:1
目的:探讨右室高位室间隔起搏与右室心尖部起搏的血流动力学不同。方法:60例缓慢心律失常患者,具有起搏器植入指征。随机分组,分别行右室高位室间隔起搏(A组)及右室心尖部起搏(B组)治疗。分别于术前、术后行心电图,超声心动图检查。观察QRS波时限,左心室射血分数(LVEF),左室舒张末期内径,每搏量(Sv),E峰值,E/A值,二尖瓣返流量。结果:右室高位室间隔起搏,与右室心尖部起搏比较,QRS波时限增宽程度小,LVEF以及Sv降低程度小。结论:右室高位室间隔起搏比右室心尖部起搏更接近生理性起搏,对血流动力学的不利影响较小,可能是一个更佳的起搏部位。 相似文献
100.