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61.
A 65-year-old woman was admitted to our hospital with the diagnosis of gallbladder tumor. Right extended hepatic lobectomy plus lymph node dissection of the hepatoduodenal ligament and left hepaticojejunostomy with Roux-en-Y reconstruction was performed in July, 1993. The gallbladder tumor was histologically proven to be squamous cell carcinoma. Seventeen months later, the patient experienced dyspnea and pitting edema of the lower legs and was admitted, in December 1994, with a diagnosis of heart failure. Despite intensive cardiac support, she died 12 days after the second admission. Autopsy revealed multiple cardiac tumors in the left and right ventricles, left atrium, left coronary artery, and left diaphragm. Histologically, these tumors were shown to be squamous cell carcinoma, considered to have metastasized from the primary gallbladder carcinoma. As neither local recurrence of the gallbladder carcinoma nor any lymph node metastasis was found, the cardiac metastasis of the gallbladder carcinoma may have occurred via the hematogenous route. Although rare, this route of cardiac metastasis of gallbladder carcinoma may be an important aspect of distant metastasis, which should be monitored for during follow-up after resection of the primary tumor.  相似文献   
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A new optimization method of the electric power leveling system using an SMES is proposed. The SMES is parallelly connected with rolling mills in steel works. The leveling control is based on fuzzy reasoning. The SMES capacity and the scaling factors of the fuzzy controller will be optimized so that the power leveling control can be achieved and then the total cost of the added SMES cost and reduced contract electricity rate becomes lower. The optimization is carried out using a genetic algorithm and a cost reduction of 7.76 billion yen can be achieved. Power leveling simulation confirms that the proposed optimization method is very effective for designing the power leveling system. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(3): 62–69, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20049  相似文献   
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The local structure around Cu supported on Al2O3 was determined by UV/VIS/NIR and XAFS spectroscopic techniques. The relationship between catalytic performance for NO–CO–O2 reaction and the state of supported Cu species is discussed. A new method for estimating the fraction of aggregated to isolated Cu species is proposed.  相似文献   
66.

When ground source heat pump systems are installed underground, an estimate of the thermal conductivity is required to determine the desired total length of the heat exchanger (U-tube). Many large cities in Asia are built on Quaternary sediments, but the thermal conductivity of these sediments is not well understood. To measure the thermal conductivity of Pleistocene volcanic sediments in Tokyo, Japan, we discuss methods of measuring thermal conductivity and factors influencing the thermal conductivity of volcanic sediment, which has low quartz content. The results obtained from experiments using a drill core, borehole data and artificial sediment samples are as follows: (1) values of thermal conductivity predicted using water content, porosity or sand content can be underestimated in volcanic sediment or sediments with large amounts of magnetic minerals; (2) magnetic minerals have a higher thermal conductivity than quartz, so there is a relationship between magnetic susceptibility and thermal conductivity: (3) comparison of thermal conductivity measurements performed using box- and needle-type probes showed that the values measured using the former are comparatively larger. This decrease in thermal conductivity is explained by formation of air-filled cracks when the needle penetrates the sediment, as air has a lower thermal conductivity than sediment.

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The channel assignment problem involves not only assigning channels or frequencies to each radio cell. but also satisfying frequency constraints given by a compatibility matrix. The proposed parallel algorithm is based on an artificial neural network composed of nm processing elements for an n-cell-m-frequency problem. The algorithm runs not only on a sequential machine but also on a parallel machine with up to a maximum of nm processors. The algorithm was tested by solving eight benchmark problems where the total number of frequencies varied from 100 to 533. The algorithm found the solutions in nearly constant time with nm processors. The simulation results showed that the algorithm found better solutions than the existing algorithm in one out of eight problems  相似文献   
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Absorbed dose to tooth enamel was examined against external photon exposure by measurements with thermoluminescence dosemeters (TLDs) and Monte Carlo calculations. TLDs were placed in a realistic physical phantom to measure dose to the teeth region in a head. A voxel-type phantom was constructed from computed tomography (CT) images of the physical phantom. Monte Carlo calculations with this voxel-type phantom were performed to analyse the results of the experiments. The data obtained were compared to the enamel doses, which were calculated with a modified MIRD-type phantom and already given in a previous paper. It was confirmed that the data derived with the MIRD-type phantom are applicable for retrospective individual dose assessments by electron spin resonance (ESR) dosimetry using teeth for the photon energy region above 300 keV. The analysis, however, indicated that the configuration of the head can affect the enamel dose relative to external exposure to photons with energy below 100 keV.  相似文献   
69.
There is a need to calculate specific absorbed fractions (SAFs) in voxel phantoms for internal dosimetry. For this purpose, an EGS4 user code for calculating SAFs using voxel phantoms was developed on the basis of an existing EGS4 user code for external dosimetry (UCPIXEL). In the developed code, the transport of photons, electrons and positrons in voxel phantoms can be simulated, particularly the transport simulations of secondary electrons in voxel phantoms. The evaluated SAFs for the GSF 'Child' voxel phantom using the developed code were found to be in good agreement with the GSF evaluated data. In addition, SAFs in adult voxel phantoms developed at JAERI were evaluated using the developed code and were compared with several published data. It was found that SAFs for organ self-absorption depend on the organ masses and would be affected by differences in the structure of the human body.  相似文献   
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