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Recent advances in understanding of the molecular mechanisms of antigen processing and presentation, and the identification of tumor-associated antigens in melanoma and other cancers, have stimulated the development of a new generation cancer vaccines. This review summarizes the most recent approaches for the design of safe and more effective vaccines for cancer. Peptide-based vaccines are safe and can be synthesized with high purity and reproducibility. Recombinant viruses encoding tumor-associated antigens allow efficient delivery and precise control over the form and the quantity of the delivered antigens. DNA-based vaccines induce long-lasting immune responses and are considered very safe. Antigen-loaded dendritic cells, and the use of newly developed adjuvants are also very promising new approaches. In this review, we also discuss the possible clinical applications and future directions for vaccine development.  相似文献   
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There have been 28 previously reported cases of neuroblastoma associated with congenital heart disease. Because many of these have been defects of the conotruncal region, it has been proposed that abnormal neural crest cell migration or maturation may be a factor that links these normally disparate pathologic conditions. Most neuroblastomas in these cases have been detected at autopsy or by radiologic studies conducted in the evaluation of the cardiac anomalies. Recently, we discovered an occult posterior mediastinal neuroblastoma in a patient undergoing a unifocalization procedure for tetralogy of Fallot with pulmonary atresia and major aortopulmonary collaterals. The tumor was resected, and the patient has demonstrated no evidence of residual or metastatic neuroblastoma.  相似文献   
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BACKGROUND: Bidirectional cavopulmonary shunt and Fontan repair are now commonly performed in patients with a variety of forms of complex single ventricle, including those with anomalies of systemic or pulmonary venous return. These anomalies are ideally dealt with during bidirectional cavopulmonary shunt, thereby minimizing the complexity of the eventual Fontan procedure. METHODS: Between March 1990 and December 1995, 36 patients with anomalous systemic or pulmonary venous drainage underwent bidirectional cavopulmonary shunt. A combination of anomalous systemic and pulmonary venous drainage was present in 12 patients, whereas 19 patients had anomalous drainage only from the systemic circulation and 5 patients had isolated anomalies of pulmonary venous return. Visceral heterotaxy syndrome was diagnosed in 18 patients. The median age at operation was 11 months, and bidirectional cavopulmonary shunt was the first surgical procedure performed in 10 of these patients. Techniques of repair are described. RESULTS: There were two early deaths and one bidirectional cavopulmonary shunt was taken down, for mortality and failure rates not significantly different than those for all patients undergoing bidirectional cavopulmonary shunt during this time period (n = 117). At a mean follow-up of 19.9 months, there have been three late deaths and 11 patients have undergone Fontan completion. Actuarial survival was 87% at 1 year and 81% at 3 years. Among all patients undergoing bidirectional cavopulmonary shunt during this time period, neither heterotaxy syndrome nor anomalies of systemic or pulmonary venous return were significantly associated with decreased survival or poor outcome. CONCLUSIONS: Bidirectional cavopulmonary shunt can be performed in patients with anomalous systemic or pulmonary venous drainage, including those with visceral heterotaxy syndrome, with morbidity and mortality rates that do not differ significantly from those achieved in all patients undergoing bidirectional cavopulmonary shunt. In this report, we describe our experience with this group of patients, primarily focusing on outcomes and technical issues that pertain to the use of bidirectional cavopulmonary shunt as a preparatory procedure for the extracardiac conduit Fontan operation.  相似文献   
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This study was conducted to compare gross efficiency (GE), net efficiency (NE), work efficiency (WE), and delta efficiency (DE) between arm crank and cycle exercise at the same relative intensities. Eight college-aged males underwent two experimental trials presented in a randomized counterbalanced order. During each trial subjects performed three intermittent 7-min exercise bouts separated by 10-min rest intervals on an arm or semirecumbent leg ergometer. The power outputs for the three bouts of arm crank or cycle exercise corresponded to 50, 60, and 70% of the mode-specific VO2peak. GE, NE, and WE were determined as the ratio of Kcal.min-1 equivalent of power output to Kcal.min-1 of total energy expended, energy expended above rest and energy expended above unloaded exercise, respectively. DE was determined as the ratio of the increment of Kcal.min-1 of power output above the previous lower intensity to the increment of kcal.min-1 of total energy expended above the previous lower intensity. GE and NE did not differ between arm crank and cycle exercises. However, WE was lower (P < 0.05) during arm crank than cycle exercise at 50, 60, and 70% VO2peak. DE was also lower (P < 0.05) during arm crank than cycle exercise at delta 50-60 and at delta 60-70% VO2peak. It is concluded metabolic efficiency as determined by work and delta efficiency indices was lower during arm crank compared with cycle exercise at the same relative intensities. These findings add to the understanding of the difference in metabolic efficiency between upper and lower body exercise.  相似文献   
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One hundred and fifty lungs from the cases below 15 years of age with various congenital heart diseases and 80 controls were used for histometrical and histological studies. Cases with congenital heart disease were divided into two groups of the increased and the decreased pulmonary blood flow. In the former group, the thickness of the pulmonary arterial media was the same as that of controls in the neonatal period, and through the wall thickness gradually decreased in a pattern seen in controls, the thickness was constantly larger than that of controls. In some cases, the media increased gradually within 6 months after birth. Pneumonia and massive pulmonary hemorrhage were seen in a higher incidence in autopsy cases. Pneumonia in younger infants was histologically characteristic and possibly more correlated to their death. In the latter group, most of the cases were with the thinner medias of the pulmonary arteries. Massive pulmonary hemorrhage was not common in the latter group.  相似文献   
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