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91.
Temporary intermittent complete heart block (CHB) occurred the day after interventional closure of an ASD with a 30 mm Gore Septal Occluder (GSO?) in a 2 years and 11‐month‐old female. CHB disappeared without further treatment and stable sinus rhythm recovered within 3 days. Only short episodes of 2nd degree AV‐block (Wenckebach periodicity) at rare intervals were documented in Holter‐monitors the following 2 months. Eleven months after device implantation the patient suffered from long lasting episodes of CHB. Surgical removal of the device resulted in incomplete recovery of AV‐conduction. Histopathological work‐up of the explanted GSO showed complete endothelialization of the device and regular scar formation. One year after surgery, the child had sinus rhythm during daytime but needed VVI‐pacing while sleeping. Young age, inferior localization of the defect, and use of a large device have been individual risk factors for CHB in this patient. Clinical course and histologic findings indicate that mechanical compression was the only cause for CHB. The cumulative number of reports of CHB after use of different ASD‐devices supports the recommendation to postpone the intervention in asymptomatic patients to preschool‐age. Early removal of a pushing device may increase the chance of complete recovery from CHB. © 2015 Wiley Periodicals, Inc.  相似文献   
92.
Transcatheter pulmonary valve (TPV) replacement is an effective therapy of right ventricular outflow tract conduit dysfunction. Acute complications after TPV implantation include infective endocarditis, stent fracture, and device dislocation. We present a novel, life-threatening complication: an acute, noninfectious TPV thrombosis. Within 24 hours after implantation of a Melody system (Medtronic, Inc, Minneapolis, MN), the patient developed an acute TPV thrombosis characterized by severe TPV stenosis on echocardiography and contrast filling defects on computed tomography pulmonary angiography images. Genetic testing revealed heterozygous prothrombin G20210A polymorphism and homozygous 4G/4G polymorphism of the plasminogen-activator-inhibitor. The patient recovered after surgical valve replacement with a pulmonary homograft.  相似文献   
93.
目的:分析载脂蛋白B(apoB)基因EcoRI、XbaI、MspI位点和载脂蛋白AI(apoAI)基因-75bp、+83bp位点多态性与哈萨克族人冠心病的关系.方法:采用聚合酶链式反应-限制性片段长度多态性分析法检测185例哈萨克族冠心病患者和216例哈萨克族非冠心病对照者的这些位点多态性.结果:①TC、TG及apoA...  相似文献   
94.
Objectives: The aim of this animal study was to establish a shunt connection between superior vena cava (SVC) and right pulmonary artery (RPA) by transvascular intervention solely. Background: After initial shunt creation, the establishment of the upper cavo‐pulmonary anastomosis (UCPA) is the second out of three open chest operations young infants with univentricular anatomy are subjected to. To avoid the risks of reoperation with cardiovascular bypass, we sought to replace this surgical step by an interventional technique. Methods: After cannulation of jugular and femoral veins in four piglets (mean body weight of 12.5 kg) an UCPA was created by radiofrequency perforation from the SVC across the right atrium into the RPA and subsequent implantation of covered stents. The perforation was guided by biplane fluoroscopy and the perforation wire premounted with a coaxial catheter was advanced into the distal pulmonary artery and exchanged for a stiffer wire. A long sheath was brought into the RPA and an 80 mm long expanded poly‐tetra‐fluoro‐ethylene (ePTFE)‐covered Cheatham Platinum stent was then implanted connecting the SVC with the RPA. Results: Immediate angiography showed antegrade flow from SVC to RPA. Angiographic re‐evaluation after a median period of 4 weeks showed partial in‐stent stenosis but patent lumina. Additionally, veno‐venous collaterals from the SVC to the right atrium had developed. Histology of the explanted stents revealed parietal thrombi and mild to moderate pseudo intima proliferation inside the lumina. Conclusions: The transvascular creation of an upper unidirectional cavo‐pulmonary anastomosis in piglets is technically feasible using standard catheterization equipment. © 2012 Wiley Periodicals, Inc.  相似文献   
95.
2-Chloro-2'-deoxyadenosine (CldAdo) and 9-beta-D-arabinosyl-2- fluoroadenine (F-ara-A) have shown marked activity in the treatment of indolent lymphoid malignancies. Based on the susceptibility of various lymphocyte populations to apoptosis, we investigated whether CldAdo or F-ara-A would induce this process in lymphocytes from patients with chronic lymphocytic leukemia (CLL). In vitro exposure of leukemic lymphocytes to CldAdo or F-ara-A for 24 to 72 hours elicited features of apoptosis visible by light and electron microscopy. Analysis of DNA integrity showed DNA cleavage into nucleosomal-sized multimers. Using a quantitative assay, drug-induced DNA fragmentation was both time and dose dependent. Inhibition of active macromolecular synthesis did not prevent drug-induced fragmentation; however, both drug-induced and spontaneous DNA fragmentation were prevented by intracellular calcium chelation. In vitro culture with phorbol ester generally decreased drug- induced DNA cleavage. After prolonged incubation, CLL cells exhibited spontaneous cleavage; albeit, at significantly lower rates than drug- treated cells. Heterogeneity was observed for spontaneous and drug- induced DNA fragmentation and was significantly lower in B-leukemic cells obtained from patients with high-risk and refractory disease. We conclude that CldAdo and F-ara-A are potent inducers of apoptotic death in CLL and that this feature correlates with the disease status.  相似文献   
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98.
A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties.  相似文献   
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100.
Twelve of 19 patients with myeloproliferative disorders showed a decrease of absence of the largest multimers of plasma von Willebrand factor (vWF) that correlated with elevated platelet counts but not with leukocyte counts. This suggested that platelets, rather than leukocytes, may be associated with the pathogenesis of the acquired vWF abnormality seen in these patients. To examine the hypothesis further, we studied 12 patients with reactive thrombocytosis after splenectomy. Increased platelet count (> 5 x 10(11)/L) after splenectomy was associated with vWF abnormalities indistinguishable from those detected in patients with myeloproliferative disorders. Accordingly, there was an inverse correlation between proportion of large vWF multimers and platelet, but not leukocyte, number: normalization of the platelet count was accompanied by restoration of a normal vWF multimeric pattern. These findings suggest that an increase in the number of platelets circulating in blood may favor the adsorption of larger vWF multimers onto the platelet membrane, resulting in their removal from the circulation and subsequent degradation.  相似文献   
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