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As the proportion of racial, ethnic, and cultural minorities in the United States continues to expand, pediatric emergency medicine providers are increasingly likely to encounter cultural and language barriers in practice. This paper reviews a conceptual framework encompassing the decision to seek emergency care, the process of providing such care, and the adherence to treatment plans and follow-up. The ways in which cultural and language barriers can negatively impact each element of this model are discussed in detail. Specific examples include provider ignorance of dangerous folk beliefs, communication barriers secondary to inappropriate interpreter use, and discriminatory assumptions regarding child abuse, pain management, and sexual activity. The practitioner is then provided with concrete recommendations to reduce these negative effects.  相似文献   
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Resection of a segment of mandible, particularly when associated with malignant disease, carries a high morbidity and mortality. Traditional methods of autogenous bone grafting have proved unreliable in immediate reconstruction of such mandibular defects because of the variability of the recipient bed. These unfavorable conditions for bone graft survival can be largely overcome using vascularized bone and vascularized soft tissue reconstruction. The radial forearm free flap has proved a versatile and useful method in intraoral reconstruction and can be used together with a segment of radius as a composite flap. The technique of raising a segment of vascularized radius is described and its use in immediate reconstruction of the mandible at the time of resection illustrated in a series of 14 consecutive cases. There was one microvascular failure in this series and one postoperative death. The remaining 12 cases have had a successful outcome and show clinical union in the follow-up period varying from 11-36 months. There is evidence indicating that the bone maintains its viability even in the presence of preoperative or early postoperative radiotherapy.  相似文献   
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c-Myc promotes cell growth and transformation by ill-defined mechanisms. c-myc(-/-) mice die by embryonic day 10.5 (E10.5) with defects in growth and in cardiac and neural development. Here we report that the lethality of c-myc(-/-) embryos is also associated with profound defects in vasculogenesis and primitive erythropoiesis. Furthermore, c-myc(-/-) embryonic stem (ES) and yolk sac cells are compromised in their differentiative and growth potential. These defects are intrinsic to c-Myc, and are in part associated with a requirement for c-Myc for the expression of vascular endothelial growth factor (VEGF), as VEGF can partially rescue these defects. However, c-Myc is also required for the proper expression of other angiogenic factors in ES and yolk sac cells, including angiopoietin-2, and the angiogenic inhibitors thrombospondin-1 and angiopoietin-1. Finally, c-myc(-/-) ES cells are dramatically impaired in their ability to form tumors in immune-compromised mice, and the small tumors that sometimes develop are poorly vascularized. Therefore, c-Myc function is also necessary for the angiogenic switch that is indispensable for the progression and metastasis of tumors. These findings support the model wherein c-Myc promotes cell growth and transformation, as well as vascular and hematopoietic development, by functioning as a master regulator of angiogenic factors.  相似文献   
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The close genetic relationship of human and animal strains of norovirus has raised the possibility of transmission of noroviruses from animals to humans and may explain the emergence of certain norovirus strains. To assess if exposure to bovine noroviruses (NoV) might result in infection in humans, an enzyme immunoassay (EIA) was designed and validated in order to detect antibodies against bovine norovirus. This and two other EIAs were used to test sera from 210 veterinarians and 630 matched population controls for IgG and IgA antibodies to recombinant capsid protein of bovine NoV (rBoV), Norwalk virus (rNV), and Lordsdale virus (rLDV). Of 840 participants, IgG reactivity to rBoV was found in 185 (22%), to rNV in 638 (76%) and to rLDV in 760 (90%). IgG reactivity to rBoV was more common in veterinarians (58/210: 28%) than in controls (127/630: 20% [P = 0.03]). IgA reactivity to rBoV was similar in both veterinarians and controls. Cross-reactivity of IgA and IgG antibodies to rBoV and rNV was seen, but 26% of all specimens positive rBoV antibodies showed high IgG reactivity to rBoV but low reactivity to rNV, suggesting a specific response to bovine antigen. No evidence of overall cross-reactivity of antibodies to rBoV and rLDV was seen. Among veterinarians, youth spent on farm (Odds Ratio [OR] = 1.8) and membership of the bovine practitioners' society (OR = 2.7) were significantly associated with IgG seroreactivity to rBoV. These data indicate that bovine strains of NoV may infect humans though less frequently than human strains.  相似文献   
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