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31.
Lymphoepithelioma-like carcinoma of the skin is a rare tumor with a microscopic resemblance to lymphoepitheliomatous tumors of the nasopharynx. A 62-year-old woman exhibited such a tumor on the nose together with regional lymph node metastases. Histologically, irregular islands of atypical epithelial cells unconnected to the overlying epidermis were surrounded by or mixed with numerous lymphocytes in the primary tumor. No squamous or glandular differentiation was present. Metastases to the submandibular lymph nodes appeared as glassy squamous cells that resembled trichilemmal keratinization. Staining of the tumor tissues with S-100 protein antibody revealed the presence of numerous short dendritic cells in clusters of epithelial cells. Total resection and adjunctive radiotherapy have led to a 6-year period free of recurrence. This is the second case report of this condition in Japan. 相似文献
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33.
Z Chen Y Sahashi K Matsuo H Asanuma H Takahashi T Iwasaki Y Suzuki C Aizawa T Kurata S Tamura 《Canadian Metallurgical Quarterly》1998,16(16):1544-1549
The ability of plasmid DNA encoding various influenza viral proteins from the A/PR/8/34 (H1N1) virus to protect against influenza was compared in BALB/c mice. The plasmid DNA encoded hemagglutinin (HA), neuraminidase (NA), matrix protein (M1), nucleoprotein (NP) or nonstructural protein (NS1) in a chicken beta-actin-based expression vector (pCAGGS). Each DNA was inoculated twice 3 weeks apart at a dose of 1 microgram per mouse by particle-mediated DNA transfer to the epidermis (gene gun). Seven days after a second immunization, mice were challenged with the homologous virus and the ability of each DNA to protect mice from influenza was evaluated by decreased lung virus titers and increased survival. Mice, given HA- or NA-expressing DNA, induced a high level of specific antibody response and protected well against the challenge virus. On the other hand, mice given M1-, NP-, or NS1-DNA failed to provide protection, although M1- and NP-DNAs did induce detectable antibody responses. These results indicate that both HA- and NA-expressing DNAs for the surface glycoproteins are most protective against influenza from among the various viral protein-expressing DNAs used here. 相似文献
34.
BACKGROUND: We report an unusual case of acquired dural-pial arteriovenous malformation (AVM) following sinus thrombosis. CASE DESCRIPTION: Initial angiography performed in a 39-year-old man showed thrombosis of the superior sagittal sinus (SSS) and the right transverse sinus (TS) but no vascular malformations. Follow-up angiography 29 months later revealed recanalization of the SSS and the TS, retrograde cortical venous drainage which suggested that thrombosis of the sinuses probably propagated into the adjacent parietal cortical veins, and development of a dural-pial AVM at or near the site of thrombi in more than one cortical vein. Complete surgical excision of the lesion was accomplished without neurological deterioration. CONCLUSIONS: The present case suggests the possibility that the pial AVM is not only a congenital condition but also may develop as an acquired lesion. 相似文献
35.
36.
Information geometry of Boltzmann machines 总被引:3,自引:0,他引:3
A Boltzmann machine is a network of stochastic neurons. The set of all the Boltzmann machines with a fixed topology forms a geometric manifold of high dimension, where modifiable synaptic weights of connections play the role of a coordinate system to specify networks. A learning trajectory, for example, is a curve in this manifold. It is important to study the geometry of the neural manifold, rather than the behavior of a single network, in order to know the capabilities and limitations of neural networks of a fixed topology. Using the new theory of information geometry, a natural invariant Riemannian metric and a dual pair of affine connections on the Boltzmann neural network manifold are established. The meaning of geometrical structures is elucidated from the stochastic and the statistical point of view. This leads to a natural modification of the Boltzmann machine learning rule. 相似文献
37.
Thin uniform β-FeSi2 films were fabricated on ion irradiated Si(100) substrates to achieve an atomically flat interface. Ion irradiation produces a surface with more defects than chemical etching; however, it is expected that the presence of defects can promote the formation of compound films such as β-FeSi2 that require interdiffusion and reaction processes. However, excess defects can also result in random nucleation, poor crystallinity and a rough interface. Cross-sectional transmission electron microscopy was used to determine the optimum conditions for ion irradiation of the substrate to obtain a clear β-FeSi2/Si interface. 相似文献
38.
Kinya Nakamura Masaki Kurata Takanari Ogata Takeshi Yokoo Michael A. Mignanelli 《Journal of Phase Equilibria and Diffusion》2001,22(3):259-264
An isothermal section of the Fe-Pu-U ternary system at 650 °C was assessed in a previous study. In the present study, the
predictions of the phase relations in the Fe-Pu-U system to higher and lower temperatures were performed by applying the interaction
parameters determined at 650 °C. Differential thermal analysis (DTA) for the Fe-Pu-U alloys was also carried out to confirm
the phase relations in the temperature region of 500 to 800 °C. Both results agreed well. On the basis of the predicted ternary
phase diagram, the phase relations for a region surrounded by Fe2Pu, Fe2U, U, and Pu were described by a reaction scheme and a projection of the liquidus surface. 相似文献
39.
Catalin Popa Yuki Okayasu Ken-ichi Katsumata Toshihiro Isobe Nobuhiro Matsushita Akira Nakajima Taisuke Kurata Kiyoshi Okada 《Journal of Materials Science》2013,48(2):941-947
Porous mullite ceramics with unidirectionally oriented pores were prepared by an extrusion method using rayon fibers as the pore formers. Rayon fibers of 8.1, 9.6, 16.8, and 37.6 μm in diameter were used as the pore formers and were kneaded with alumina powder, kaolin clay, China earthen clay, and water to form pastes. These pastes were extruded into cylindrical tubes, dried, and fired at 1500 °C for 4 h. The apparent porosities ranged from 45.7 to 48.2 %. The pore size distributions showed a sharp peak at 9.4, 10.0, 15.6, and 30 μm with increasing fiber diameters. The height of the capillary rise was 1780, 1670, 1320, and 950 mm with increasing fiber diameter. The maximum capillary rise is much higher than previously reported. The contact angle and effective pore radius that determine the capillary rise ability were calculated by fitting the capillary rise curves using the Fries and Dreyer’s equation. 相似文献
40.
Abstract A method of describing centrosymmetric gratings (radial, circular and spiral) is presented. The moiré-fringe profile produced by centrosymmetric gratings is analysed using polar coordinates. The concept of the angle of intersection for two superimposed gratings is examined and it is shown how from this study moiré patterns formed from centrosymmetric gratings can be analysed automatically by digital computer. Examples of theoretically predicted patterns, generated by the proposed procedure, are compared with actual moiré-fringe patterns. This method provides for the first time a procedure that can be used in engineering for improving the contrast of moiré patterns and for sharpening these patterns. 相似文献