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71.
We report a renal cell carcinoma which presented as a metastasis to the larynx. The only preoperative clue to the diagnosis was its hypervascularity.  相似文献   
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To evaluate the usefulness of transendoscopic sonography, we have studied the use of a new sonographic probe of 6 F diameter in 11 fresh specimens. We achieved a precise imaging of well known anatomic structures and, moreover, obtained an additional dimension in endoscopy, since the sonographic probe adds a transverse scan to the endoscopic view, like a mini-CT at the tip of the probe. In this way, we also examined the guiding characteristics of this imaging technique, both in real time and on-line. Our results promise further interesting aspects of this technique in minimally invasive neurosurgery and suggest that further development and clinical experience seem to be justified.  相似文献   
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Sources of asbestos in drinking water may be natural deposits or the use of asbestos cement for water distribution. 50 water samples were selected in Austria to detect fibre contamination from either geology or asbestos cement by comparison with control areas and by comparison of raw and treated water. Standardized EPA/BGA methodology with transmission electron microscopy, energy dispersive X-ray analysis and selected area electron diffraction was used to quantify concentrations of different sized amphibole and chrysotile fibres. In 10 areas with asbestos deposits and in 14 areas with use of asbestos cement pipes asbestos concentrations in drinking water were low and not significantly different from 6 control areas (median 32,000 total asbestos fibres per litre). The relative highest concentration was found in an area with natural deposits at the source of the water supply (190,000 per litre). In areas without natural deposits the increase of asbestos concentrations from origin to consumer of water was not significant and unrelated to water aggressiveness, age and length of asbestos cement pipes. This could be mainly due to the fact that in areas with aggressive water asbestos cement pipes have been coated in Austria. A sample from a cistern, however, showed considerable asbestos contamination and raises concern about the use of surface water for room air humidification.  相似文献   
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The discrete ordered median problem (DOMP) integrates classical discrete location problems, such as the N-median, N-center and Uncapacitated Facility Location problems. It was introduced by Nickel (In: Fleischmann B, Lasch R, Derigs U, Domschke W, Rieder U, editors. Operations Research Proceedings 2000, Berlin: Springer, 2001. p. 71–76), who formulated it as both a nonlinear and a linear integer program. We propose an alternative integer linear programming formulation for the DOMP, discuss relationships between both integer linear programming formulations, and show how properties of optimal solutions can be used to strengthen these formulations. Moreover, we present a specific branch and bound procedure to solve the DOMP more efficiently. We test the integer linear programming formulations and this branch and bound method computationally on randomly generated test problems.  相似文献   
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Melt-blown polybutylene terephthalate (PBT) nonwoven materials treated by using plasma is regarded as one of the excellent materials to filter white blood cells (WBC) from blood.In this paper, dielectric barrier discharge (DBD) plasma source at an improved quasi-stable atmospheric pressure is achieved when discharge voltage, discharge current, and gap between the electrodes are carefully controlled. This plasma source has been used to modify the surface of PBT melt-blown nonwoven materials. Experimental results indicate that both the wettablity and permeation of treated PBT melt-blown nonwoven materials are greatly improved.  相似文献   
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Mineral contents, haem and non-haem iron of rhea (Rhea americana) muscles Obturatorius medialis (OM), Iliotibialis lateralis (IL) and Iliofibularis (I) were determined. No differences between the three muscles were observed for calcium, phosphorus, magnesium and sodium. There is more potassium, zinc and copper in IL muscle than in OM and I muscles. For Manganese, OM and IL muscles show a higher content in comparison with I muscle. For selenium, IL and I muscles show the highest content compared to OM muscle. For total, haem and non-haem iron, the IL muscle shows the highest content respect to the other muscles. When compared to other meats, the minerals content of rhea meat show an elevated level in phosphorus, selenium and total and haem iron. The human health concern due to the deficient diet in selenium and iron, and their high contents in rhea meat will be of great importance in the promotion of this meat.  相似文献   
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