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Pleomorphic liposarcoma (PLPS) is a rare, high‐grade sarcoma defined by the presence of pleomorphic lipoblasts. Constituting 5% of all liposarcomas, PLPS usually arises in deep soft tissues of the extremities, with rare occurrences in the dermis and subcutis. We describe a unique case of an 85‐year‐old Caucasian gentleman with a 1 year history of a pedunculated, pink, non‐tender papule on the dorsum of his left arm, measuring 1.0 cm in maximum dimension. Biopsy revealed a dermal collection of atypical epithelioid and spindle cells superimposed on a sclerotic background, resembling a pleomorphic fibroma on low power. On high power, a central focus of discrete adipocytic differentiation with pleomorphic lipoblasts was present. Tumor cells were positive for S‐100 and negative for desmin, actin, CD68, keratin, MART‐1 and CD34. Clinicopathologic findings were consistent with PLPS and the diagnosis was made. PLPS is rarely localized to the dermis and one with low power features resembling a pleomorphic fibroma has not been previously described in the literature. 相似文献
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Carrie Heincelman Seth Brown Eric England Kaushal Mehta Robert D. Wissman 《Skeletal radiology》2014,43(9):1297-1299
Rib stress injuries are uncommonly reported but have been documented among athletes, most notably rowers. There have only been two prior case reports of rib stress injuries in swimmers, both of which were young females. Magnetic resonance (MR) imaging was either not obtained or the imaging characteristics were incompletely described. We present a case of an isolated third rib stress injury in a collegiate male swimmer diagnosed via MR imaging. We briefly discuss the possible etiologies for rib stress injuries, their MR appearance, as well as their treatment. 相似文献
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Seth M. Noar Richard Crosby Christina Benac Greg Snow Adewale Troutman 《AIDS and behavior》2011,15(5):1045-1057
The purpose of the current investigation was to apply the attitude-social influence-efficacy (ASE) model to achieve a theory-based understanding of condom use among low income, heterosexually active African-American STD clinic patients. N = 293 participants were recruited from a large, publicly-funded metropolitan STD clinic in the Southeastern United States and surveyed using an ACASI computer program. Results indicated that several ASE variables exhibited meaningful relationships with condom stages of change in univariate analyses, replicating patterns found in previous research. Fewer variables remained significant in multivariate analyses, however. There was also some support for the proposition that early stage movement (e.g., Precontemplation to Contemplation) is based more upon perceptions of condom use (e.g., pros, perceived norms), whereas later stage movement (e.g., Preparation to Action/Maintenance) is based more upon perceived and actual skills acquisition (e.g., condom self-efficacy, negotiation strategies). Results varied with regard to main and casual condom stage of change. Implications for developing tailored HIV prevention interventions with heterosexual African-Americans are discussed. 相似文献
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Alison E. Murray Fabien Kenig Christian H. Fritsen Christopher P. McKay Kaelin M. Cawley Ross Edwards Emanuele Kuhn Diane M. McKnight Nathaniel E. Ostrom Vivian Peng Adrian Ponce John C. Priscu Vladimir Samarkin Ashley T. Townsend Protima Wagh Seth A. Young Pung To Yung Peter T. Doran 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(50):20626-20631
The permanent ice cover of Lake Vida (Antarctica) encapsulates an extreme cryogenic brine ecosystem (−13 °C; salinity, 200). This aphotic ecosystem is anoxic and consists of a slightly acidic (pH 6.2) sodium chloride-dominated brine. Expeditions in 2005 and 2010 were conducted to investigate the biogeochemistry of Lake Vida’s brine system. A phylogenetically diverse and metabolically active Bacteria dominated microbial assemblage was observed in the brine. These bacteria live under very high levels of reduced metals, ammonia, molecular hydrogen (H2), and dissolved organic carbon, as well as high concentrations of oxidized species of nitrogen (i.e., supersaturated nitrous oxide and ∼1 mmol⋅L−1 nitrate) and sulfur (as sulfate). The existence of this system, with active biota, and a suite of reduced as well as oxidized compounds, is unusual given the millennial scale of its isolation from external sources of energy. The geochemistry of the brine suggests that abiotic brine-rock reactions may occur in this system and that the rich sources of dissolved electron acceptors prevent sulfate reduction and methanogenesis from being energetically favorable. The discovery of this ecosystem and the in situ biotic and abiotic processes occurring at low temperature provides a tractable system to study habitability of isolated terrestrial cryoenvironments (e.g., permafrost cryopegs and subglacial ecosystems), and is a potential analog for habitats on other icy worlds where water-rock reactions may cooccur with saline deposits and subsurface oceans. 相似文献
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