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We report a case of a 19-year-old man who showed a brownish, elastic-soft, multilocular, pedunculated, solid tumor (10 × 6 × 6 cm), with scale crust and erosion, on the medial side of the right thigh. The histopathology of a specimen removed completely revealed a tumor that was located between the middle layer of the dermis and the subcutaneous fatty tissue, was filled with a mucoid material, and was surrounded by a fibrous tissue. The tumor consisted of small thin-walled blood vessels and spindle-shaped or stellate tumor cells without cytological atypia in addition to the mucoid material. Immunohistochemistory revealed that the tumor cells express the vimentin stain. Based on these clinical and histologic findings, we diagnosed the skin condition as superficial angiomyxoma.  相似文献   
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The aim of this study was to ultrasonically characterize photodamaged skin of the elderly at the microscopic level using scanning acoustic microscopy which showed two-dimentional distribution of sound speed in the skin section. We confirmed that the expression level of the elastin gene was increased in the preauricular skin (photodamaged area), compared with postauricular skin (photo-protected area). The expression level of the procollagen gene was also increased in the preauricular skin compared with postauricular skin. The preauricular skin showed higher sound speed in the papillary dermis (Grenz zone). The site of progressive solar elastosis showed a somewhat sound speed velocity than that of the Grenz zone. Immunohistochemical staining showed conserved deposition of collagen in the Grenz zone even in the more photodamaged preauricular skin. These results suggest that fibrosis in the Grenz zone compensates tissue strength with the progress of solar elastosis. The sound speed analysis of skin will provide important information on heterogeneous mechanical changes in the skin during the process of photoaging.  相似文献   
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PURPOSE: To evaluate accuracy of cardiac functional analysis with multi-detector row computed tomography (CT) and segmental reconstruction algorithm over a range of heart rates. MATERIALS AND METHODS: Institutional review board approval was obtained. Informed consent was not required. Multi-detector row CT (500-msec rotation time, 8 x 1-mm detector collimation) and magnetic resonance (MR) imaging were performed in 50 patients (28 men, 22 women; age range, 46-84 years; mean age, 67 years). Two-dimensional echocardiography was performed in 41 patients, and electrocardiographically (ECG)-gated single photon emission computed tomography (SPECT) was performed in 27. End-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), and left ventricular (LV) mass were estimated with multi-detector row CT and compared with values estimated with MR imaging, which served as the reference standard. Additionally, EF values estimated with multi-detector row CT, echocardiography, and SPECT were compared with those estimated with MR imaging. Systemic error and degree of agreement of global functional parameters measured with MR imaging and other modalities were assessed. In a second analysis, linear regression analysis was added. RESULTS: EF estimated with multi-detector row CT agreed and correlated well with EF estimated with MR imaging (bias +/- standard deviation, -1.2% +/- 4.6; r = 0.96). Agreement and correlation were similar for EDV (-0.35 mL +/- 15.2; r = 0.97), ESV (1.1 mL +/- 8.6; r = 0.99), and LV mass (2.5 mL +/- 15.0; r = 0.96). Standard deviation of EF difference between multi-detector row CT and MR imaging was significantly less than that between echocardiography and MR imaging (P < .001) or that between SPECT and MR imaging (P < .001). CONCLUSION: Various LV functional parameters were measured with multi-detector row CT with a segmental approach, and measurements correlated and agreed with those obtained with MR imaging. Moreover, functional analysis with multi-detector row CT was more accurate than that with two-dimensional echocardiography or ECG-gated SPECT.  相似文献   
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Vascular calcification is the most frequent cause of death in chronic renal failure. In recent studies molecular mechanism for regulation of vascular calcification is becoming to clear. An important regulator of vascular calcification is the extracellular levels of inorganic phosphate. Also, various bone matrix proteins and factors regulates vascular calcification in ESRD patients.  相似文献   
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