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51.
Fontan conversion with arrhythmia surgery.   总被引:2,自引:0,他引:2  
OBJECTIVE: Hemodynamic abnormalities and refractory atrial arrhythmias in patients late after the Fontan operation result in significant morbidity and mortality. We reviewed our experience with Fontan conversion and concomitant arrhythmia surgery. METHODS: Between January 1996 and February 2004, 16 patients underwent Fontan conversion and arrhythmia surgery. Mean age at the initial Fontan operation was 5.1+/-3.5 (range: 2-15) years and mean age at Fontan conversion was 17.0+/-5.8 (range: 6-30). The initial Fontan operations were atriopulmonary connections in 14 patients, extracardiac lateral tunnel in 1, and intracardiac lateral tunnel in 1. The types of arrhythmia included atrial flutter in 10 patients and atrial fibrillation in 3. Fontan conversion operation was performed with intracardiac lateral tunnel in 5 patients and extracardiac conduit in 11. Arrhythmia surgery included isthmus cryoablation in 10 patients and right-sided maze in 3. RESULTS: There has been no mortality. At Fontan conversion operation, 7 patients required permanent pacemaker. All patients have improved to New York Heart Association class I or II. With a mean follow-up of 26.9+/-30.6 (range:1-87) months, 16 patients had sinus rhythm, 2 patients had transient atrial flutter which was well controlled, and 2 patients required permanent pacemaker during follow-up. CONCLUSIONS: Fontan conversion with concomitant arrhythmia surgery and permanent pacemaker placement is safe, improves New York Heart Association functional class, and has a low incidence of recurrent arrhythmias. In most patients, concomitant permanent pacemakers are needed.  相似文献   
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BACKGROUND: Higher house dust mite (HDM) allergen exposure during infancy has been associated with increased HDM sensitization. Infant bedding has been associated with the accumulation of varying levels of HDM. Prospective data on the relationship between infant bedding and the development of HDM sensitization has not been previously examined. OBJECTIVES: To determine if particular types of bedding used in infancy are associated with increased risk of house dust mite sensitization in childhood. METHODS: A population-based sample (n = 498) of children born in 1988 or 1989, and who were resident in Northern Tasmania in 1997, participated in this study. These children were part of a birth cohort study (1988-95), the Tasmanian Infant Health Survey. Data on infant underbedding and mattresses was available on 460 and 457 children, respectively. The main outcome measure was HDM sensitization defined as a skin prick test (SPT) reaction of 3 mm or more to the allergens of Dermatophagoides pteronyssinus and/or Dermatophagoides farinae. RESULTS: The use of either sheepskin underbedding or plastic mattress covers in infancy was associated with an increased risk of sensitization to HDM allergens at age 8 years. The adjusted risk ratio (RR) for sensitization to HDM with sheepskin in infancy was 2.27 (95% CI: 1.14, 4.55), P = 0.020. The adjusted RR for sensitization to HDM with the use of plastic mattress covers in infancy was 2.06 (95% CI: 1.22, 3.51), P = 0.007. The use of a foam mattress in infancy was not related to subsequent HDM sensitization. CONCLUSION: Infant's bedding plays a role in the development of HDM sensitization in childhood. Intervention studies to examine mite allergen levels and the role of underbedding on the development of HDM sensitization are required.  相似文献   
55.
逆行交锁髓内钉治疗股骨髁上骨折及关节僵硬   总被引:2,自引:0,他引:2  
目的:探讨应用逆行交锁强内钉治疗陈旧性股骨碟上骨折钢板断裂不愈合并膝关节僵硬的临床意义。方法:对5例患采用断裂钢板拆除,手术松解粘连,矫正畸形,股骨碟逆行交锁铝内钉固定,术后早期应用CPM机锻炼。结果:5例随访8—12个月,肢体无畸形,骨折愈合时间6—9个月,平均7.5个月,膝关节功能按Kolmert评定标准,优4例,良1例。结论:应用逆行交锁铝内钉治疗股骨碟上陈旧性骨折钢板断裂骨不愈合并膝关节僵硬,操作简便,固定牢靠,可早期功能锻炼,效果良好。  相似文献   
56.
目的:观察重症急性胰腺炎(SAP)大鼠白血病抑制因子(LIF)在肺组织中表达的时相变化, 探讨LIF在SAP病程及肺损伤中的意义.方法:36只♂SD大鼠随机分为正常对照组(N 组,n=6)、假手术组(Sham组,n=6)和重症急性胰腺炎组(SAP组,n=24).采用胰管逆行灌注50 g/L牛磺胆酸钠的方法复制大鼠SAP模型.用RT-PCR法检测肺组织中LIF mRNA的表达水平,免疫组织化学方法检测NLIF在肺组织中的表达变化.结果:SAP组3 h后肺组织LIF mRNA的表达量明显高于对照组和假手术组(灰度值:1.018± 0.065 vs 1.451±0.067,1.322±0.072,P<0,05), 并且6,12,24 h持续升高(0.853±0.058,0.635 ±0.064,0.582±0.089)(P<0.01).同样,SAP组 LIF蛋白表达在3和6 h后明显高于对照组和假手术(127.36±2.76,122.53±2.43 vs 159.46 ±2.78,156.35±3.12,P<0.05),并且12,24 h后也维持在很高的水平(109.37±2.87,102.42± 2.27).结论:LIF作为促炎症因子参与了SAP肺组织的炎症反应.  相似文献   
57.
Objectives. To evaluate the process of soft-tissue electrovaporization and to study variables that affect tissue clearance rates in a laboratory setting, in order to identify parameters that can optimize transurethral electrovaporization of the prostate.Methods. Fresh bovine skeletal muscle, equivalent in impedance and surface properties to the human prostate, was submerged in 3.3% sorbitol solution and electrovaporized with a grooved monopolar electrode attached to the weighted arm of a linear actuator. The effects of excursion rate, applied mechanical load, power setting, electrode configuration, and generator performance on the volume of tissue removed, were assessed.Results. Tissue removal increased significantly when electrode excursion rate was slowed from 25 to 15 mm/s (P <0.05) and then to 10 mm/s (P <0.05); when the load was increased from 20 to 50 g (P <0.005); and when dial power was increased from 120 to 150 W (P <0.01). Tissue removal was generator dependent. There was no significant difference between the Force 40 and the Force 2 (P > 0.4), but a new computer-controlled constant power output generator (Force FX) did significantly improve tissue vaporization at an equivalent power setting (P <0.005 and P <0.01, respectively). Tissue removal was also dependent upon electrode configuration, with the VaporTrode-Grooved Bar removing significantly more tissue than either an ungrooved roller bar of equivalent size or 2-mm smooth roller ball, respectively, both after a single pass (P <0.001 and P <0.05) and after five repeated passes (P <0.05 and P <0.005). The histologic depth of tissue thermal effect was less than 1 mm, but it was 38% greater for the VaporTrode-Grooved Bar (0.68 mm) than for the standard cutting loop (0.5 mm, P <0.01).Conclusions. Using a novel method to quantify tissue removal, we have demonstrated that electrode configuration, excursion rate, applied load, power setting, and generator performance are interdependent factors that influence the efficacy of the electrovaporization process in a fluid environment.  相似文献   
58.
本文报告23例次ATP治疗PSVT的效果,总有效率56.5%,9例次高浓度快速注射者8例转复。器质性心脏病者副作用较多,1例冠心速注高浓度ATP后,发生心室颤动和阿-斯氏综合征。这一结果提示:药物浓度和注射速度是影响疗效的主要因素,PSVT伴AVB者疗效也很低;病因和药物浓度是决定副作用的因素。因此,对于器质性心脏病者,尤其冠心病人,应避免高浓度快速静脉注射ATP。  相似文献   
59.
The edema-producing activity of NNAVPLA2, an acidic phospholipase A2 (PLA2) enzyme from Naja naja atra venom (NNAV), was less potent than that of TMVPLA2 II, a basic PLA; from Trimeresurus mucrosquamatus venom (TMV). These edema-forming effects were greatly suppressed by pretreatment of rats with diphenhydramine/ methysergide or compound 48/80, which reduced the tissue content of histamine and serotonin. Heparin abolished and suppressed the paw edema caused by protamine and TMVPLA2 II, respectively, but had no effect on the NNAVPLA2-induced response. In isolated rat peritoneal mast cells, both PLA2 concentration dependently induced the release of histamine and β-glueuronidase. Again, TMVPLA2 II was more potent than NNAVPLA2. This degranulation effect of mast cells caused by TMVPLA2 II and protamine was inhibited by heparin, while that caused by NNAVPLA2 was unaffected. The edema-forming and mast cell degranulation effects were greatly decreased in both PBPB-modified NNAVPLA2 and PBPB-modified TMVPLA2 II, in which the catalytic activity of the enzymes was completely lost. PBPB-modified TMVPLA2 II-induced paw edema was also suppressed by heparin. Furthermore, this edematous response was totally reversed in rat pretreated with aspirin in combination with diphenhydramine and methysergide. These results suggest that the edema-forming effect of PLA2 is probably dependent on the presence of catalytic, positive charge and pharmacological sites on its molecule.  相似文献   
60.
Consumers were surveyed to determine their attitudes toward four systems of health care delivery (home health care, hospitals, nursing homes, and outpatient clinics) along 10 attributes. The results are analyzed using multiple discriminant analysis. Implications for the formulation of marketing strategies are discussed.  相似文献   
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