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Pulmonary infection by Nocardia spp. has been recognized the last decades. Nocardia is an opportunistic pathogen in immunocompromised individuals; nevertheless, it has been recognized as an uncommon pathogen in immunocompetent patients. We report a case of pulmonary infection by Nocardia asteroides in an immunocompetent host who had a history of sulfate acid aspiration, followed by gastric tube interposition, reconstruction of the hypopharynx and gastric-hypopharyngial anastomosis.  相似文献   
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Neutralizing antibody (nAb) activity during the course of natural infection is believed to be crucial to combating virus propagation. The aim of this study was to measure the impact of nAb response on HCV early kinetics and genetic evolution in the liver transplantation (LT) setting. A cohort of 28 patients undergoing LT for HCV‐related cirrhosis was included in the study. Viral load, nAb titers and hypervariable region 1 (HVR1) sequences were determined in serum samples obtained before and at different time points after LT. Serum nAb titers were assessed using HCV pseudoparticles (HCVpp). HVR1 sequences were obtained by direct sequencing. Patients were classified according to viral kinetic patterns (plateau or increasing), during the first week after LT. All patients demonstrated high titers of nAbs before LT, although this was not associated with early kinetic patterns or HVR1 evolution during the first week after LT. We found that in patients with plateau HCV early kinetics, the virus required adaptive mutations, while in those with increasing viral loads, the HVR1 region remained largely conserved (p = 0.015). These data suggest that HCV adaptation via selection of the best‐fitted variants may account for early viral kinetics following LT.  相似文献   
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We have applied the temperature-dependent single-stranded conformational polymorphism (SSCP) analysis for characterization of influenza A virus cDNA fragments. A series of primers were synthesized on the basis of the comparison of hemagglutinin and PB2 gene sequences of different origin. RT-PCR reactions were run using these primers, products were denatured and single-strand DNA fragments were subjected to electrophoresis. After silver staining, ssDNA band patterns characteristic for each genotype were observed. Minor differences within a serotype were detected without need for sequencing the PCR products making the preliminary analysis of avian influenza isolates much faster.  相似文献   
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The clinical and histopathologic features of 187 high-grade endometrial cancers [FIGO grade 3 endometrioid (EC-3), serous (SC), and clear cell (CC)] were studied to determine whether clinicopathologic differences between these various histologic subtypes existed. The study group consisted of 89 EC-3s, 61 SCs, and 37 CCs. Treatment regimens were individualized. SCs and CCs were significantly more likely than EC-3s to occur in patients older than 65 years (P=0.03), and SCs tended to occur more frequently in patients of African descent than EC-3s and CCs (P=0.07), although this was not statistically significant. EC-3s had the highest rate of associated endometrial hyperplasia (P=0.05). SCs were most likely to have high-stage disease at presentation (>or=stage IIB; P=0.01), with peritoneal dissemination at diagnosis being much more common compared with EC-3s and CCs (P=0.004). Median follow-up was 39 months, and median overall survival was 47 months. Five-year survivals were 45% (EC-3), 36% (SC), and 50% (CC)-differences that were not statistically significant. In contrast, the impact of stage on survival was significant (P<0.001). Among all other factors evaluated, only age greater than 65 years was a negative predictor (risk ratio, 2.23; P<0.001), whereas a family history of cancer reduced the risk of death when controlling for stage (risk ratio, 0.54; P=0.005). When controlling for stage, race, reproductive history, personal history of cancer, histologic subtype, depth of myometrial invasion, lymphovascular invasion, presence of an endometrial polyp, presence of hyperplasia, or staging adequacy did not affect prognosis. High-grade endometrial cancers of different histologic subtypes treated in an individualized manner are associated with similar clinical outcomes, but differences in age at presentation, race distribution, association with hyperplasia, stage, and sites of tumor dissemination support the idea that these represent distinct disease entities as defined by traditional histopathologic classification of endometrial cancers.  相似文献   
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