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Wound‐dressing performances are affected by exudate viscosity, resistance to flow because of gravity, and bodyweight loads, the level of which is related to the body position. Here, we focussed on two dressing properties: (a) Sorptivity—the ability of dressings to transfer exudate away from the wound bed by capillary action—and (b) Durability—the capacity of dressings to maintain their integrity over time and during their removal. Both properties are critically important for avoiding further tissue damage but require the development of new laboratory tests for their measurement. A computer‐controlled phantom of an exuding sacral pressure ulcer has therefore been developed and used to compare the performances of Exufiber (Mölnlycke Health Care) vs an alternative market‐leading dressing. Sorptivity was determined using weight tests, and durability was measured through tensile tests of the used dressings. For a supine configuration, the Exufiber dressing demonstrated ~three times higher sorptivity and better durability, withstanding ~five times greater strain energy than the other product before failure occurred. This work paves the way for quantitative, standardised testing of dressings in all aspects of exudate management. The reported tests are further suitable for testing dressing combinations or how dressings interact with negative pressure wound therapy.  相似文献   
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Myofibroma (MF) is a benign mesenchymal myofibroblast-derived tumor, which occurs most frequently in children, and rarely affects the maxilla. We reported a case of an aggressive intraosseous lesion found in the maxilla of a 9-year-old female child. Intraorally, the swelling extended from tooth 12 to 16, causing displacement of teeth 13, 14, and 15. Computed tomography revealed a large osteolytic lesion causing thinning and cortical erosion. Microscopically, the lesion showed a proliferation of spindle-shaped cells, with elongated nuclei and eosinophilic cytoplasm, arranged in interlaced fascicles. The immunohistochemical analysis revealed cytoplasmic positivity for α-SMA and HHF-35, and negativity for desmin, laminin, S-100, β-catenin, and CD34. Ki-67 was positive in 8% of tumor cells. The diagnosis was MF. Herein, we describe an additional case of central MF arising in the maxilla, including clinical, imaging, microscopical, and immunohistochemical features, as well as a review of the literature.  相似文献   
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Journal of Public Health - Adolescents’ sleep duration has decreased over the past century; this is mainly caused by problems with falling asleep. Short sleep duration, poor sleep quality,...  相似文献   
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The aim of this study was to determine the frequency and potential relevance of the promoter polymorphisms of the tumor necrosis factor-alpha (TNF-alpha) in the severity of rheumatoid arthritis (RA) in Mexicans. HLA-DR and polymorphisms at positions -238 and -308 of TNF-alpha gene were determined in 137 Mexican RA patients (44 with severe and 93 with non-severe RA) as well as in 169 healthy controls (99 were typed for HLA-DR). We observed an increased frequency of HLA-DR4 in severe RA compared to healthy controls (pC=0.02, OR=2.33). TNF polymorphism analysis showed a significant increased frequency of TNF -238 GG genotype in the whole group of RA patients when compared to healthy controls (pC=0.007, OR=4.71). When the analyses were carried out separately in severe and non-severe RA patients, the increased frequency of -238 GG genotype only was observed in patients with non-severe forms of the disease. Analysis of -308 polymorphism showed increased frequency of -308 T2 (A) allele in severe RA when compared to non-severe disease (pC=0.011, OR=3.29) and to healthy controls (pC=0.002, OR=3.97). The data demonstrate that -308 T2 (A) allele is associated with susceptibility to develop severe RA in Mexicans. This association could be independent from HLA-DR alleles and might be used as a prognostic marker for severe RA.  相似文献   
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Professional prestige was determined using the psychophysical methods of magnitude estimation and cross-modality matching with line lengths and dynamometric forces as responses. The main results revealed that: (a) the rankings order resulting from all methods employed provide degrees of prestige which are in close agreement with the different professions (w = 0.94), (b) the non-metric continuum of professional prestige exhibits prothetic characteristics, (c) the variability of estimations is a linear function of the estimation of magnitudes, thus confirming that Ekman's law is also valid for non-metric continua, (d) the exponents obtained using matchings of number, line lengths and force of hangrip were not significantly different from the exponents predicted by the transitivity property of scales and, finally (e) the data furnish a scale of professional prestige which, at the level of ratio measurement, is valid, stable and consistent.  相似文献   
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This study developed a bioassay with the isopod Porcellio dilatatus based on the activity of the enzymes acetylcholinesterase (AChE) and lactate dehydrogenase (LDH). The in vivo effects of the insecticides parathion-ethyl and endosulfan-sulfate on AChE and LDH activities of P. dilatatus under laboratory conditions were investigated. The route of uptake of the pesticides was through the food (alder leaves). Isopods were exposed to a wide range of concentrations of parathion or endosulfan (0.1, 1, 10, 25, 50, 100, 250, and 500 microg/g of food) for 21 days. After this period, the activity of AChE and LDH was determined. Parathion induced significant depression of both AChE and LDH activities. Animals fed with endosulfan-contaminated food exhibited lower LDH activities than control animals, while AChE activity was similar in all treatments. The results of the present investigation suggest that the isopod. P. dilatatus is a suitable species for use in toxicity tests and indicate that the enzymes AChE and LDH could be used as effect criteria both in laboratory and in field studies with this species.  相似文献   
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