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51.
目的确定豚鼠心电场的分布本质。方法将26只离体豚鼠心脏浸入蒸馏水和生理盐水中,将参比点置于远离心电场源的零电位,记录3个平面左、右心室侧和与之垂直的前后侧共4个方向上不同距离的心电图。结果每一平面4个方向上共16个点在两种溶液中都记录到以正波为主的心电图。结论排除导联参比点对体表标测的影响,心电场一致向外的分布方式表明心电场不是偶极场,可能是一个拟球面分布的单源场。  相似文献   
52.
Striatal kainic acid (KA) lesions induce behavioral and biochemical deficits which resemble symptoms encountered in patients suffering from Huntington's disease. In rats with KA lesions, fetal striatal transplants have shown to reverse the pervasive nocturnal hyperactivity induced by the lesion. In the present study 4.6 mm3 of fetal striatal tissue were delivered bilaterally into the anterodorsal portion of the lesioned caudate nucleus. Care was taken to deliver the transplant within the host parenchyma and away from the lateral ventricles. Locomotor behavior analyzed using the Digiscan animal activity monitors before and after the transplants demonstrated a reversal of the hyperactivity following transplants in 70% of lesioned animals. Microinjections of horseradish peroxidase delivered into the globus pallidus and substantia nigra of a small group of functionally recovered transplanted animals, did not reveal evidence for reinnervation between host nigra or pallidum and the transplant at 10 weeks post-transplantation. Other laboratories have reported anatomical connections by 6 months post-transplantation. Ventricular/brain ratios demonstrated that intraparenchymal transplants significantly reduced the ventricular dilation following KA lesion. These results suggest that functional recovery can be obtained when the transplant is immersed into the host's striatal parenchyma regardless of the existence of long-range anatomical connections.  相似文献   
53.
An infant is presented who at birth met criteria consistent with hypoplastic left heart syndrome. He was followed clinically and by 11 weeks of age demonstrated substantial growth of the left ventricle. He underwent successful repair of coarctation of the aorta and continues to do well with moderate aortic stenosis. The difficulties of predicting left ventricular growth and function are discussed, and management options are reviewed.  相似文献   
54.
The optimal use of kidneys from small pediatric deceased donors remains undetermined. Using data from the Scientific Registry of Transplant Recipients, 2886 small (< 21 kg) pediatric donors between 1993 and 2002 were identified. Donor factors predictive of kidney recovery and transplantation (1343 en bloc; 1600 single) were identified by logistic regression. Multivariable Cox regression was used to assess the risk of graft loss. The rate of kidney recovery from small pediatric donors was significantly higher with increasing age, weight and height. The odds of transplant of recovered small donor kidneys were significantly higher with increasing age, weight, height and en bloc recovery (adjusted odds ratio = 65.8 vs. single; p < 0.0001), and significantly lower with increasing creatinine. Compared to en bloc, solitary transplants had a 78% higher risk of graft loss (p < 0.0001). En bloc transplants had a similar graft survival to ideal donors (p = 0.45) while solitary transplants had an increased risk of graft loss (p < 0.0001). En bloc recovery of kidneys from small pediatric donors may result in the highest probability of transplantation. Although limited by the retrospective nature of the study, kidneys transplanted en bloc had a similar graft survival to ideal donors but may not maximize the number of successfully transplanted recipients.  相似文献   
55.
Kidney Disease After Heart and Lung Transplantation   总被引:2,自引:0,他引:2  
Kidney disease is a commonly recognized complication of heart and lung transplantation and is associated with increased morbidity and mortality. While the spectrum of kidney disease in this population is wide-ranging, studies indicate that between 3% and 10% of these patients will ultimately develop end-stage renal disease (ESRD). This review examines the risk factors for both acute and chronic kidney injury, with a particular emphasis on the role of calcineurin inhibitor-mediated nephrotoxicity in both these settings. Against the background of current National Kidney Foundation Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines, we have further considered and recommended appropriate strategies for long-term management of kidney disease-related manifestations in heart and lung transplant recipients. Specific aspects addressed include retarding progressive renal injury and minimizing nephrotoxicity, as well as treatment of hypertension, hyperlipidemia and anemia. Finally, for patients in this population with advanced kidney disease, renal replacement therapy options are discussed. Based on the impact of chronic kidney disease on outcomes in both heart and lung recipients, we advocate early referral to a nephrologist for patients displaying evidence of significant renal dysfunction.  相似文献   
56.
BK virus nephropathy (BKVN) is now recognized as a major cause of renal allograft loss. Recent reports suggest that retransplantation in patients with graft loss due to BKVN is safe after return to dialysis. Since early transplantation is associated with improved outcomes, it would be advantageous if this procedure could be performed prior to ultimate graft loss. However, little data are available regarding the safety of this approach during active viremia. In this report, we describe successful preemptive retransplantation with simultaneous allograft nephrectomy in two patients with active BKVN and viremia at the time of surgery. With 21- and 12-month follow-up, respectively, both patients have stable allograft function and no evidence for active viral replication. We conclude that preemptive retransplantation can be considered in patients with failing allografts due to BKVN.  相似文献   
57.
58.
采用放射免疫法测定60例心血管病患儿的血浆心钠素,结果,在心功能不全,先天性心脏病、心肌炎者,明显高于正常组;心功能不全组明显高于非心功能不全组。非心功能不全的心血管疾患(如:先天性心脏病、心肌炎)之间无显著差异。说明血浆心钠素测定可作为心功能不全判断指标,并可指导治疗。  相似文献   
59.
N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. S. Savel'ev.) Translated from Byulleten' Ékperimental'noi Biologii i Meditsiny, Vol. 113, No. 3, pp. 327–329, March, 1992.  相似文献   
60.
Consecutive survivors of a myocardial infarction from the Southern Hospital, below 70 years of age, were randomized into a Control group (n=276) and a Treatment group (n=279). The latter was openly prescribed the combination of clofibrate and nicotinic acid for serum lipid lowering. Each patient should remain in the study for 5 years and be seen regularly every 4 months at a special IHD outpatient clinic within the hospital. The concentration of serum cholesterol and triglyceride was lowered by 13% and 19%, respectively, in the Treatment group compared to the Control group. Total mortality was 82 cases in the Control group and 61 in the Treatment group, a 26% reduction (p<0.05). For patients above 60 years of age in the Treatment group the reduction in mortality was 28% (p<0.05). IHD mortality was reduced by 36% (p<0.01)in the Treatment group compared to the Control group. The beneficial effect of the serum lipid lowering treatment was related to the serum triglyceride concentration in two ways. First, it only occurred in patients with a triglyceride level >1.5 mmol/l (n=216). Secondly, it was most pronounced in the 44% of the treated patients who had a lowering of the serum triglyceride concentration by 30% or more, and in this subgroup the reduction of IHD mortality was 60% (p<0.01). For serum cholesterol there were no such relations. The difference between serum triglycerides and cholesterol concerning these relations to the treatment outcome may be due to the fact that hypertriglyceridaemia was the most common hyperlipidaemia among our patients, occurring in 50%, while hypercholesterolaemia only occurred in 13 %. Caution should be exercised in the interpretation of the results as the trial was not blind. However, the fact that the decrease in IHD deaths was directly related to the degree of serum triglyceride lowering indicates that it was the drug effect on serum lipids that was reponsible for the beneficial effect of the treatment.  相似文献   
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