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991.
For preservice teachers in early childhood education, having a rich exposure to multiple forms of literacy in diverse communities is an essential dimension of their teacher education. In this study, 10 Australian preservice early childhood education students, in the first year of their course, visit two early childhood settings in a large city in Vietnam to make deeper connections between literacy and practice contexts. They photographed literacy events and explored them to deepen their understandings of literacy. This paper examines photographs selected by these student teachers drawing on a framework used by Swedish and New Zealand (NZ) students, which focused on identifying a range of literacy concepts. We found that the Australian students focused on themes, meaning making and visual images for illustrating literacy comparison more frequently than their NZ and Swedish counterparts. Thus, the Mellgreen and Margrain framework has merit for teacher educators in expanding literacies in intercultural contexts.  相似文献   
992.
Cutaneous squamous cell carcinoma (SCC) with osteoclast‐like giant cells (hereafter, osteoclastic cells) is very rare; eight cases have been reported since 2006. Whether the osteoclastic cells represents a reactive or neoplastic change remains a matter of debate. Osteoclastic cells are often observed in the sarcomatous component of cutaneous carcinosarcoma. SCC with osteoclastic cells is a heterogeneous condition that includes SCC with stromal changes containing osteoclastic cells (also known as osteoclast‐like giant cell reaction) and carcinosarcoma. In some cases, SCC with an associated osteoclast‐like giant cell reaction has been differentiated from carcinosarcoma based on the degree of cytologic atypia in non‐epithelial components. We summarized the clinical and histopathologic characteristics of 11 patients of SCC with osteoclastic cells, including our two cases of SCC with an osteoclast‐like giant cell reaction and one case of carcinosarcoma. The affected patients were old and more likely to be male (64%). Seven cases (64%) were in the head and neck. Moreover, multiple features of high risk SCC were observed, such as a tumor size greater than 2 cm (56%), moderate or poor differentiation (100%), recurrence (33%) and nodal metastasis (17%) after excision and immunosuppression (27%). Interestingly, half of the previously reported cases of SCC with osteoclastic giant cell reaction had histopathologic findings that were overlapping with those of carcinosarcoma.  相似文献   
993.
Commercial fishing continues to have one of the highest rates of occupational fatalities compared with other work sectors in the United States. Attitudes/beliefs among Vietnamese shrimp fishermen of the Gulf of Mexico may influence behaviors that are risk factors for fatal and nonfatal injuries. The study employs a community trial with quasi-experimental pretest/posttest intervention design. An advisory group made up of key stakeholders including representatives from the US Coast Guard was assembled. A survey was designed using the Theory of Planned Behavior as the theoretical framework. Three community groups at port sites along the Texas/Louisiana Gulf Coasts were identified. Focus groups were convened at each site to select priority areas for risk intervention using training and awareness measures. Initial and follow-up surveys were administered pre-/post-interventions for each of the three community groups (2008, n = 217 completed surveys; 2012, n = 206 completed surveys). The follow-up survey was condensed and “intent to act” questions were added for the priority concerns identified (noise-induced hearing loss, machinery/winches, and fatigue). Statistically significant changes (P ranging from .000 to .042) were observed in selective attitude/belief responses for hearing/noise and fatigue. Intent to action or to adopt the intervention was high among all three groups of shrimp fishermen (hearing conservation, 82.4%; machinery/winch safety, 94.6%; fatigue awareness, 95.3%). Simple, yet culturally appropriate training and awareness measures in the form of visual and written safety messages favorably influence attitudes, beliefs, and behavioral intent related to priority risk factors identified by Vietnamese commercial shrimp fishermen along the Texas and Louisiana Gulf Coasts.  相似文献   
994.
For the large array of self-peptide/MHC class II (pMHC-II) complexes displayed in the body, it is unclear whether CD4+ T cell tolerance must be imparted for each individual complex or whether pMHC-II–nonspecific bystander mechanisms are sufficient to confer tolerance by acting broadly on T cells reactive to multiple self-pMHC-II ligands. Here, via reconstitution of T cell–deficient mice, we demonstrate that altered T cell selection on a single prostate-specific self-pMHC-II ligand renders recipient mice susceptible to prostate-specific T cell infiltration. Mechanistically, this self-pMHC-II complex is required for directing antigen-specific cells into the Foxp3+ regulatory T cell lineage but does not induce clonal deletion to a measurable extent. Thus, our data demonstrate that polyclonal T reg cells are unable to functionally compensate for a breach in tolerance to a single self-pMHC-II complex in this setting, revealing vulnerabilities in antigen-nonspecific bystander mechanisms of immune tolerance.  相似文献   
995.
Proteus mirabilis forms dense crystalline biofilms on catheter surfaces that occlude urine flow, leading to serious clinical complications in long-term catheterized patients, but there are presently no truly effective approaches to control catheter blockage by this organism. This study evaluated the potential for bacteriophage therapy to control P. mirabilis infection and prevent catheter blockage. Representative in vitro models of the catheterized urinary tract, simulating a complete closed drainage system as used in clinical practice, were employed to evaluate the performance of phage therapy in preventing blockage. Models mimicking either an established infection or early colonization of the catheterized urinary tract were treated with a single dose of a 3-phage cocktail, and the impact on time taken for catheters to block, as well as levels of crystalline biofilm formation, was measured. In models of established infection, phage treatment significantly increased time taken for catheters to block (∼3-fold) compared to untreated controls. However, in models simulating early-stage infection, phage treatment eradicated P. mirabilis and prevented blockage entirely. Analysis of catheters from models of established infection 10 h after phage application demonstrated that phage significantly reduced crystalline biofilm formation but did not significantly reduce the level of planktonic cells in the residual bladder urine. Taken together, these results show that bacteriophage constitute a promising strategy for the prevention of catheter blockage but that methods to deliver phage in sufficient numbers and within a key therapeutic window (early infection) will also be important to the successful application of phage to this problem.  相似文献   
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