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1.
We report a large kindred in which a punctate palmoplantar keratoderma (PPK) is associated with malignancy, including Hodgkin's disease, renal, breast, pancreatic and colonic adenocarcinomas. The family was traced through four generations, and over 320 individuals were identified, of whom 49 had punctate PPK. The punctate PPK appeared to be inherited as an autosomal dominant trait with variable penetrance. Ten of the 43 adults (23%) with punctate PPK developed malignancies, and five of these developed before the age of 50. Of the 271 unaffected individuals, six (2%) have developed malignancies, one prior to the age of 50. The association of keratoderma and malignancy is discussed.  相似文献   
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Theoretical and experimental results on boundary acoustic waves propagated along a ZnO layer sandwiched between two materials are presented. It is shown that boundary acoustic waves can exist only when the material constants of the three materials satisfy the particular conditions obtained here. Experiments on SiO(2)/ZnO/SiO(2 ) were performed to verify the theoretical prediction of the existence of boundary waves. Boundary waves were excited and received by interdigital transducers and propagated along the ZnO layer. Propagation loss was practically the same as for Rayleigh waves, indicating a proper mode of the system. The results suggest that future SAW (surface acoustic wave) devices can be made without any package.  相似文献   
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The aim of this study was to clarify the change of the gastric mucosa following inoculation with Helicobacter pylori (H. pylori). Two pairs of cynomolgus monkeys received either H. pylori of human origin (group A) or H. pylori of monkey origin (group B) by intragastric inoculation at a dose of 10(9) CFU. After inoculation, endoscopical observation and biopsies were done every 7 days for one month. The bacteria in the biopsy samples were cultured quantitatively. The content of intracellular PAS-AB positive substance was quantitatively analyzed with the image analyzing system. Results were as follows: 1) Before inoculation, the gastric mucosa was endoscopically normal and free from H. pylori. 2) The quantity of H. pylori varied from 0 to 10(3) CFU/0.1 g tissue in group A and from 10 to 10(6) CFU/0.1 g tissue in group B. 3) Severe erosion was seen in group B, while mild mucosal erythema and erosion were observed in group A. 4) There was a correlation between the quantity of H. pylori and histological activity (Rauws' gastritis score). 5) The PAS-AB positive substance in H. pylori-positive mucosa was less than that in H. pylori-negative mucosa. In conclusion, gastric mucosal changes of varying degrees were brought about after inoculation of H. pylori depending on the quantity of bacilli in the gastric tissue.  相似文献   
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There is little data on the diagnostic reliability of the ultrasonic Doppler technique for vertebral arterial occlusive lesions. Percutaneous vertebral Doppler examination and the vertebral angiograms were compared to determine the diagnostic reliability of this technique in 64 vertebral arteries of 53 patients with cerebrovascular disease. The percutaneous vertebral Doppler findings were quantitatively analyzed using a sound spectrograph and were classified into three types: no flow signal type, poor flow type and normal flow type. In nine patients with the no flow type the angiograms revealed vertebral occlusion or a missing vertebral artery in six, giving a diagnostic reliability of 67%. In 17 patients with poor flow type the angiograms revealed vertebral occlusion or a missing vertebral artery in five, terminal narrowing of the artery in nine, and hypoplasia in two giving a diagnostic reliability of 94%. For all vertebral arteries examined with this technique, including normal ones, the diagnostic reliability was 92% (59/64). Percutaneous vertebral Doppler examination has clinical usefulness as a screening test for occlusive vertebral arterial diseases.  相似文献   
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Fabrication of wurtzite-type gallium nitride (GaN) thick films on HPVE-grown {0001} GaN substrates under moderate ammonothermal conditions is reported. Supercritical ammonia (NH3) as solvent and the mineralizer ammonium chloride (NH4Cl) is employed for temperature and pressure conditions of 400–550 °C and ≤135 MPa, respectively. Growth rates of 30 μm per day over long-term growth runs were obtained. The effect of surface morphology of the substrate on homoepitaxial nucleation of GaN films prepared from ammonoacid solutions is investigated. Two-dimensional nucleation is obtained for substrates etched by hot concentrated KOH prior film growth. In this case the interface between film and the ( ) substrate does not show any signs of voids or island nucleation. Cracking pattern reveals similar mechanical-elastical properties for film and substrate.  相似文献   
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Boron nitride (BN) nanotubes, nanohorns and nanocoils were synthesized by annealing Fe4N/B, FeB and Fe/B powders at 1000 °C for 1–24 h in nitrogen gas atmosphere, and large amounts of BN nanotubes were obtained by annealing Fe4N/B. The growth mechanism and atomic structures were investigated on cup-stacked BN nanotubes synthesized from Fe4N/B by X-ray diffraction, high-resolution electron microscopy, electron diffraction and energy dispersive X-ray spectroscopy. As-produced BN soot was purified by removing non-BN nanomaterials such as metal catalyst particles and unreacted boron, and high purity BN nanotubes were obtained.  相似文献   
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Hydrogen-containing Ta2O5 (Ta2O5:H) thin films are considered to be a candidate for a proton-conducting solid-oxide electrolyte. In this study, Ta2O5:H thin films were prepared by reactively sputtering a Ta metal target in an O2 + H2O mixed gas. The effects of sputtering power and post-deposition heat treatment on the ion conducting properties of the Ta2O5:H thin films were studied. The ionic conductivity of the films was improved by decreasing the RF power and a maximum conductivity of 2 × 10−9 S/cm was obtained at an RF power of 20 W. The ionic conductivity decreased by heat-treatment in air, and no ion-conduction was observed after treatment at 300 °C due to the decrease in hydrogen content in the films.  相似文献   
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