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21.
The rise in human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) has prompted a quest for further understanding of the role of high-risk HPV in tumor initiation and progression. Patients with HPV-positive OPSCC (HPV+ OPSCC) have better prognoses than their HPV-negative counterparts; however, current therapeutic strategies for HPV+ OPSCC are overly aggressive and leave patients with life-long sequalae and poor quality of life. This highlights a need for customized treatment. Several clinical trials of treatment de-intensification to reduce acute and late toxicity without compromising efficacy have been conducted. This article reviews the differences and similarities in the pathogenesis and progression of HPV-related OPSCC compared to cervical cancer, with emphasis on the role of prophylactic and therapeutic vaccines as a potential de-intensification treatment strategy. Overall, the future development of novel and effective therapeutic agents for HPV-associated head and neck tumors promises to meet the challenges posed by this growing epidemic.  相似文献   
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The chemical structure of amino adhesives produced by the strongly acid process was investigated by 13C Nuclear Magnetic Resonance spectroscopy. This technique allowed the identification of functional groups and its quantitative determination. Concentration of cyclic polymeric structures (urons) was shown to be related with adhesive performance and with particleboard physico‐mechanical properties and formaldehyde content. Higher urons concentration presented lower viscosity and reactivity. Particleboards produced with resins with lower urons concentration presented lower formaldehyde content, but also lower internal bond strength. Wood‐based panels produced fulfilled E1 class requirements for formaldehyde emissions, indicating that strongly acid process is an alternative to the conventional alkaline–acid process. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4500–4507, 2013  相似文献   
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Porous magnesium has a great potential to be used as degradable bone scaffolds. In this study, porous magnesium with 35% percolating porosity has been successfully fabricated through powder metallurgy route utilizing space holders. The intrinsic mechanical properties of the porous magnesium were measured by nanoindentation testing and analyzed with the Oliver–Pharr method. Afterward, a ceramic coating on the surface of the porous magnesium was performed by plasma electrolytic oxidation (PEO) treatment in a silicate‐based solution. The morphology and composition results of the PEO coatings indicated that it is possible to apply a homogenous and adhesive ceramic coating layer on all free surface of the porous magnesium through PEO method. The protective performance of the PEO coatings was evaluated using by potentiodynamic polarization and electrochemical impedance spectroscopy tests in simulated body fluid. The results revealed the PEO coating significantly improves biocorrosion resistance of the porous magnesium. Therefore, it can be used as an effective method to control the degradation rate of porous magnesium implants in the human body.  相似文献   
25.
Reactive oxygen species (ROS) and reactive nitrogen species (RNS) contribute to the pathogenesis and/or progression of several human diseases. Proteins are important molecular signposts of oxidative/nitrosative damage. However, it is generally unresolved whether the presence of oxidatively/nitrosatively modified proteins has a causal role or simply reflects secondary epiphenomena. Only direct identification and characterization of the modified protein(s) in a given pathophysiological condition can decipher the potential roles played by ROS/RNS-induced protein modifications. During the last few years, mass spectrometry (MS)-based technologies have contributed in a significant way to foster a better understanding of disease processes. The study of oxidative/nitrosative modifications, investigated by redox proteomics, is contributing to establish a relationship between pathological hallmarks of disease and protein structural and functional abnormalities. MS-based technologies promise a contribution in a new era of molecular medicine, especially in the discovery of diagnostic biomarkers of oxidative/nitrosative stress, enabling early detection of diseases. Indeed, identification and characterization of oxidatively/nitrosatively modified proteins in human diseases has just begun.  相似文献   
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Embryonic development is associated with extensive vascular growth and remodeling. We used immunohistochemical, light and electron microscopical techniques, as well as vascular casting methods to study the developing chick embryo kidney with special attention to the interplay between sprouting and intussusceptive vascular growth modes. During inauguration at embryonic day 5 (E5), the early mesonephros was characterised by extensive microvascular sprouting. By E7, the vascular growth mode switched to intussusception, which contributed to rapid kidney vasculature growth up to E11, when the first obvious signs of vascular degeneration were evident. The metanephros underwent similar phases of vascular development inaugurating at E8 with numerous capillary sprouts and changing at E13 to intussusceptive growth, which was responsible for vascular amplification and remodeling. A phenomenal finding was that future renal lobules arose as large glomerular tufts, supplied by large vessels, which were split into smaller intralobular feeding and draining vessels with subsequent formation of solitary glomeruli. This glomerular duplication was achieved by intussusception, i.e., by formation of pillars in rows and their successive merging to delineate the vascular entities. Ultimately, the maturation of the vasculature was achieved by intussusceptive pruning and branching remodeling. An interesting finding was that strong VEGF expression was associated with the sprouting phase of angiogenesis while bFGF was upregulated during the phase of intussusceptive microvascular growth. We conclude that microvascular growth and remodeling in avian kidney follows an adroitly crafted pattern, which entails a precise spaciotemporal interplay between sprouting and intussusceptive angiogenic growth modes supported partly by VEGF and bFGF.  相似文献   
27.

This paper explores the relationship between the concept of quality of life (QoL) and housing circumstances among the immigrant and local population of two neighbourhoods in Norway: Storhaug in Stavanger and Grünerløkka in Oslo. Objective data regarding housing circumstances, e.g., type of residence, dimension or overcrowding, is collected through spatial analysis and desktop-research. Inhabitants of these neighbourhoods are interviewed with the help of map-based questionnaires to collect both objective data regarding these housing circumstances as well as subjective data, e.g. reason of location and personal satisfaction with housing and QoL. The objective and subjective data is analysed geographically and statistically. This study finds that the immigrant group has less favourable housing circumstances than the local population. Circumstances such as type of residence, the reason of location and satisfaction with the residence are predictors for satisfaction with QoL between both groups. Being local or immigrant, as well as the study area, Storhaug and Grünerløkka, or the type of ownership were not significant predictors of satisfaction with QoL in this specific study. These findings provide a base for understanding the importance of housing circumstances for QoL. Due to the high percentage of the immigrant population and its projection in Norway, these investigations are expected to help practitioners identify housing features and design aspects that can impact on the overall satisfaction with QoL of both host and immigrant society.

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28.
Several explanations have been proposed to understand the existence of nested subset patterns in biological communities, including selective extinction, differential colonization, nested species-habitat relationships, random placement from a common species pool, and human disturbance. We study if songbird assemblages inhabiting urban parks in the Puebla-Cholula Metropolitan Area (Mexico, an urbanizing country) exhibit a nested subset pattern, and apply information-theoretic (IT) methods to rank the likelihood of the abovementioned processes as competing hypotheses explaining nestedness. A total of 21 study sites were considered, where 38 Passeriformes species were retained for nestedness analyses (13 species with preferences for forest habitats, and 25 for non-forest habitats). Neither the number of species per site nor the number of sites per species followed expectations from the random placement hypothesis. In addition, using the NODF index for measuring nestedness and different null models for generating random matrices, we found that songbird assemblages inhabiting urban parks were significantly more nested than expected. The IT approaches we followed evidenced that the two most important ecological processes promoting nestedness were selective extinction and human disturbance: site richness orderly increased according to area, and decreased according to background noise levels. Results are discussed taking into account habitat-related sound degradation and transmission properties, and differential susceptibility to anthropogenic noise among songbirds with preferences for forest versus non-forest habitats. To the best of our knowledge, this is the first time that noise pollution, a pervasive kind of human disturbance in modern cities, is acknowledged as a factor promoting nestedness in bird communities.  相似文献   
29.
The decomposition of a model pharmaceutical compound, pentoxifylline, in aqueous solution was investigated using a dielectric barrier discharge (DBD) in coaxial configuration, operated in pulsed regime, at atmospheric pressure and room temperature. The solution was made to flow as a film over the surface of the inner electrode of the plasma reactor, so the discharge was generated at the gas-liquid interface. Oxygen was introduced with a flow rate of 600 sccm. After 60 min plasma treatment 92.5% removal of pentoxifylline was achieved and the corresponding decomposition yield was 16 g/kWh. It was found that pentoxifylline degradation depended on the initial concentration of the compound, being faster for lower concentrations. Faster decomposition of pentoxifylline could be also achieved by increasing the pulse repetition rate, and implicitly the power introduced in the discharge, however, this had little effect on the decomposition yield. The degradation products were investigated by liquid chromatography-mass spectrometry technique (LC-MS). The evolution of the intermediates during plasma treatment showed a fast increase in the first 30 min, followed by a slower decrease, so that these products are almost completely removed after 120 min treatment time.  相似文献   
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