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981.
982.
ABSTRACT: Osteoporotic bone marrow defect of the jaws has been reported as a poorly demarcated radiolucency that affect mainly posterior mandible of middle-aged woman. The incidence of this condition is not exactly established and its pathogenesis remains unknown. An additional unusual case of osteoporotic bone marrow defects occurring bilaterally in the mandibular edentulous regions of a 32-year-old white woman is presented reinforcing its diagnostic criteria and histopathological findings.  相似文献   
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984.
Dengue viruses and other members of the Flaviviridae family are emerging human pathogens. Dengue is transmitted to humans by Aedes aegypti female mosquitoes. Following infection through the bite, cells of the hematopoietic lineage, like dendritic cells, are the first targets of dengue virus infection. Dendritic cells (DCs) are key antigen presenting cells, sensing pathogens, processing and presenting the antigens to T lymphocytes, and triggering an adaptive immune response. Infection of DCs by dengue virus may induce apoptosis, impairing their ability to present antigens to T cells, and thereby contributing to dengue pathogenesis. This review focuses on general mechanisms by which dengue virus triggers apoptosis, and possible influence of DC-apoptosis on dengue disease severity.  相似文献   
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Health care workers (HCWs) may transmit respiratory infection to patients. We assessed evidence for the effectiveness of vaccinating HCWs to provide indirect protection for patients at risk for severe or complicated disease after acute respiratory infection. We searched electronic health care databases and sources of gray literature by using a predefined strategy. Risk for bias was assessed by using validated tools, and results were synthesized by using a narrative approach. Seventeen of the 12,352 identified citations met the full inclusion criteria, and 3 additional articles were identified from reference or citation tracking. All considered influenza vaccination of HCWs, and most were conducted in long-term residential care settings. Consistency in the direction of effect was observed across several different outcome measures, suggesting a likely protective effect for patients in residential care settings. However, evidence was insufficient for us to confidently extrapolate this to other at-risk patient groups.  相似文献   
988.
Oocyte maturation in the thelytokous parthenogenetic tick Amblyomma rotundatum was examined for the first time using light and scanning electron microscopy. The panoistic ovary lacks nurse and follicular cells and is a single continuous tubular structure forming a lumen delimited by the ovarian wall. Oocytes of tick species are usually classified according to cytoplasm appearance, the presence of germinal vesicle, the presence of yolk granules, and the chorion. However, for this species, we also use oocyte size as an auxiliary tool since most oocytes were in stages I–III and were histologically very similar. Oocytes were classified into five development stages, and specific characteristics were observed: mature oocytes with thin chorion, pedicel cells arranged forming an epithelium with two or more oocytes attached by the same structure, and a large number of oocytes in the process of reabsorption.  相似文献   
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990.
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