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71.
We conducted a study to determine prevalence of HPV types in oropharyngeal cancers in the United States and establish a prevaccine baseline for monitoring the impact of vaccination. HPV DNA was extracted from tumor tissue samples from patients in whom cancer was diagnosed during 1995–2005. The samples were obtained from cancer registries and Residual Tissue Repository Program sites in the United States. HPV was detected and typed by using PCR reverse line blot assays. Among 557 invasive oropharyngeal squamous cell carcinomas, 72% were positive for HPV and 62% for vaccine types HPV16 or 18. Prevalence of HPV-16/18 was lower in women (53%) than in men (66%), and lower in non-Hispanic Black patients (31%) than in other racial/ethnic groups (68%–80%). Results indicate that vaccines could prevent most oropharyngeal cancers in the United States, but their effect may vary by demographic variables.  相似文献   
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目的评价InVance球部悬吊术治疗前列腺癌根治术后压力性尿失禁的临床效果。方法回顾性分析2005年3月至2011年3月采用InVance球部悬吊术治疗6例前列腺癌根治术后压力性尿失禁患者的临床资料。结果6例手术时间80~120min,出血量20~50ml。术后2d拔除气囊导尿管,切口均Ⅰ期愈合。随访12~29个月,4例治愈,1例改善,1例无效。2例出现暂时性尿潴留,1例出现短期内会阴疼痛。6个月后最大尿流率(15.9±7.7)ml/s,残余尿量0-20ml/s。结论InVance球部悬吊术简单、创伤小、手术并发症少,对前列腺癌根治术后压力性尿失禁有较好疗效。  相似文献   
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目的对1个隐性营养不良型大疱性表皮松解症家系进行基因检测及产前诊断。方法利用PCR-Sanger测序技术检测患者COL7A1基因的全部外显子及其侧翼区的潜在变异,之后进行家系验证及产前基因诊断。结果Sanger测序显示患者COL7A1基因存在c.7289delC(p.Pro2430Glnfs*36)及c.7474C>T(p.Arg2492*)复合杂合变异,分别遗传自其母亲和父亲,在100名健康对照中未检测到上述变异。产前诊断胎儿COL7A1基因c.7289位置未见变异,c.7474位置存在C>T杂合变异,判断为携带者。结论明确了1例隐性营养不良型大疱性表皮松解症家系COL7A1基因的致病性变异,并成功进行了产前诊断。  相似文献   
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Previous studies examining the association between p73 G4A and gastric cancer risk have produced inconsistent results. The objective of this study was to clarify whether p73 G4A plays a major role in the development of gastric cancer. Studies that had examined the association between p73 G4A and gastric cancer risk were identified through PubMed, Science Direct, and CNKI. We selected eligible studies based on inclusion criteria. Odds ratios were estimated using distinct genetic models, and the heterogeneity between studies was explored using Cochran’s Q statistic along with the I2 statistic. Overall, we found no evidence of a significant association between p73 G4A and risk of gastric cancer. A same trend was also indicated in subgroup analysis by ethnicity. The heterogeneity tests revealed that there was no significant heterogeneity across studies. Our meta-analysis indicates that p73 G4A might not have a major effect on risk of gastric cancer. A much larger study is required to validate our findings.  相似文献   
76.
Recycled aggregate concrete-filled steel tubular (RACFST) columns are widely recognized as efficient structural members that can reduce the environmental impact of the building industry and improve the mechanical behavior of recycled aggregate concrete (RAC). The objective of this study is to investigate the behavior of recycled aggregate concrete-filled circular steel tubular (RACFCST) stub columns subjected to the axial loading. Three-dimensional finite element (FE) models were established using a triaxial plastic-damage constitutive model of RAC considering the replacement ratio of recycled aggregates. The FE analytical results revealed that the decreased ultimate bearing capacity of RACFCST stub columns compared with conventional concrete infilled steel tubular (CFST) columns was mainly due to the weakened confinement effect and efficiency. This trend will become more apparent with the larger replacement ratio of recycled aggregates. A practical design formula of the ultimate bearing capacity of RACFCST stub columns subjected to axial load was proposed on the basis of the reasonably simplified cross-sectional stress nephogram at the ultimate state. The derivation process incorporated the equilibrium condition and the superposition theory. The proposed equation was evaluated by comparing its accuracy and accessibility to some well-known design formulae proposed by other researchers and some widely used design codes.  相似文献   
77.
Au/Pd/ZnO nanoclusters with ultra-low noble metal loadings were prepared by a one-step and ligand-free method at room temperature. HRTEM, ICP-MS, XPS, and elemental mapping analysis confirmed that the obtained Au/Pd/ZnO nanoclusters were composed of ZnO nanoclusters decorated with well-dispersed AuPd nanoparticles. Au/Pd/ZnO nanoclusters exhibited higher photocatalytic activity compared with those of pristine ZnO, Au/ZnO and Pd/ZnO. Moreover, the high catalytic activity of Au/Pd/ZnO nanoclusters could be maintained even after 5 cycles of photocatalytic reaction. A mechanism for the enhanced photocatalytic performance was also suggested, which was in light of the synergistic effects of the SPR effect from Au and the improved photogenerated charge carrier separation from Pd.

Au/Pd/ZnO nanoclusters with ultra-low noble metal loadings were prepared by a one-step and ligand-free method at room temperature. The obtained Au/Pd/ZnO nanoclusters were composed of ZnO nanoclusters decorated with well-dispersed AuPd NPs with ultra-low noble metal loading.  相似文献   
78.
Various preforms of carbon nanotubes (CNTs), such as fibers, yarns, or buckypapers (BP), have been developed over the last few years in order to fabricate advanced nanocomposites containing a high volume fraction of the reinforcing phase. However, a homogeneous dispersion and an even isolation of CNTs during the fabrication process of many preforms such as BP is often challenging, while the poor interaction between CNTs and the matrix also limits the final performance of the nanocomposites. Herein, a new route to overcome these two challenges simultaneously has been demonstrated based on an active dispersant (noted as Py-PEI) developed through the quaternization reaction of pyrene derivatives (Py-Br) and polyethylenimine (PEI). The existence of pyrene groups leads to the formation of π–π stacking with CNTs, successfully hindering the re-aggregation of dispersed CNTs. Meanwhile, the amine groups of Py-PEI can establish covalent bonds with epoxy, leading to an enhanced load transfer efficiency between CNTs and epoxy in the composites. Systematic characterization of both fabricated BP and BP-reinforced nanocomposites have been performed, with significantly enhanced CNT dispersion stability in water together with improved mechanical performance of the as-obtained BP/epoxy nanocomposites. This study provides a new strategy in fabricating high performance nanocomposites with the ease of nanofiller dispersion and enhanced reinforcing efficiency.

The active dispersant Py-PEI remarkably enhanced the dispersing stability of CNTs in water and the mechanical performance of BP/epoxy composites.  相似文献   
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