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Aortic allograft valves were harvested from non-infected (bacterial or viral) cadavers within 24 hours of death with a family consent, and were sterilized by 4 degrees C antibiotic solution for 48 hours. Then, the allograft was preserved in the 4 degrees C nutrient medium (fresh; TC-199, calf serum and HEPES buffer) or in liquid nitrogen (-196 degrees C) after freezing to -80 degrees C by a programmed freezer. 10% dimethylsulfoxide (DMSO) was used for cryopreservation. Following germ-free confirmation, aortic allograft valves were implanted in 5 patients having aortic regurgitation with good results. Three fresh and two cryopreserved allograft valves were used. Although the follow-up term is very short (maximum 1 year) at the present time, the valve function is quite satisfactory, confirmed by cardiac catheterization and echocardiography. This is the first report in Japan with regard to cryopreservation of allograft valves and clinical use of fresh or cryopreserved valves. We believe that realization and progress of allograft preservation by cryo-technique and establishment of the tissue bank are important for the development of cardiovascular surgery in Japan.  相似文献   
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To elucidate the clinical characteristics of pulmonary edema in unstable angina, 120 patients with unstable angina who admitted to the hospital within 6 hours after the onset of chest pain were studied. The criteria for the diagnosis of pulmonary edema included interstitial pulmonary edema and diffuse alveolar edema. Pulmonary edema was present in 24 patients. In these patients, the duration of chest pain was relatively longer, and the incidences of diabetes mellitus, emergency coronary revascularization and multiple-vessel coronary artery disease were higher than in those without pulmonary edema. In addition, in-hospital mortality rate in patients with pulmonary edema was higher than in those without it (21 vs 1%, p < 0.001), which is probably due to a large area of myocardial ischemia. For these patients, therefore, early diagnosis and appropriate therapy to save viable segments of the myocardium are mandatory.  相似文献   
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BACKGROUND: Prepulse inhibition (PPI) is an operational measure of sensorimotor gating and is impaired in a family of neuropsychiatric disorders characterized by abnormalities of inhibitory function. Adults with autistic disorder (AD) exhibit clinical features of inhibitory deficits, such as restrictive and repetitive behaviors, that may be explained by deficits in sensorimotor gating. METHODS: Acoustic startle reactivity, habituation, and PPI (30-, 60-, 120-msec interstimulus intervals) were assessed in 14 adult men diagnosed with AD and 16 typically developing normal comparison (NC) participants. All participants were administered measures of intelligence and frontal-executive functioning. RESULTS: Adults with AD exhibited significantly less PPI in the 60-msec condition than NC participants, which was correlated with increased ratings of restricted and repetitive behaviors. The groups did not differ on measures of startle amplitude or overall habituation. There was, however, a significant group-by-block habituation effect. Furthermore, PPI was not related to intelligence but was moderately associated with performance on a measure of frontal-executive functioning. CONCLUSIONS: Adults with AD have sensorimotor gating deficits similar to other neurodevelopmental disorders, implicating a failure of normal inhibitory regulation of sensory, motor, and attentional mechanisms. Thus, PPI deficits may be indirectly linked to one of the hallmark features of AD.  相似文献   
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Recent serologic, immunoprotection, and pathogenesis studies identified the Lig proteins as key virulence determinants in interactions of leptospiral pathogens with the mammalian host. We examined the sequence variation and recombination patterns of ligA, ligB, and ligC among 10 pathogenic strains from five Leptospira species. All strains were found to have intact ligB genes and genetic drift accounting for most of the ligB genetic diversity observed. The ligA gene was found exclusively in L. interrogans and L. kirschneri strains, and was created from ligB by a two-step partial gene duplication process. The aminoterminal domain of LigB and the LigA paralog were essentially identical (98.5 ± 0.8% mean identity) in strains with both genes. Like ligB, ligC gene variation also followed phylogenetic patterns, suggesting an early gene duplication event. However, ligC is a pseudogene in several strains, suggesting that LigC is not essential for virulence. Two ligB genes and one ligC gene had mosaic compositions and evidence for recombination events between related Leptospira species was also found for some ligA genes. In conclusion, the results presented here indicate that Lig diversity has important ramifications for the selection of Lig polypeptides for use in diagnosis and as vaccine candidates. This sequence information will aid the identification of highly conserved regions within the Lig proteins and improve upon the performance characteristics of the Lig proteins in diagnostic assays and in subunit vaccine formulations with the potential to confer heterologous protection.  相似文献   
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