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81.
T Ichikawa Y Nakajima H Fujimoto A Koyama M Honma M Yatsuzuka K Ohtomo G Uchiyama S Ushigome S Ohba 《Canadian Metallurgical Quarterly》1997,26(10):602-605
We present a case of giant calcifying epithelioma of Malherbe (pilomatrixoma) in the right upper arm of a 62-year-old man. It measured 18 x 12 x 8 cm in size, making it the largest of all the cases reported previously. CT clearly demonstrated a well-defined, subcutaneous mass with amorphous calcifications. The mass showed intermediate signal intensity on T2*-weighted MR images and slight contrast uptake on contrast-enhanced MR images. Histopathologically, this tumor showed no aggressive or malignant nature. The patient is without evidence of recurrence or metastasis 3 years following the resection. 相似文献
82.
This paper presents a modularized simulation modelling framework for evaluating the impacts on economic cost and CO2 emissions resulting from the introduction of a solid oxide fuel cell (SOFC) system into the existing mix of centralized power generation technologies in Japan. The framework is comprised of three parts: a dual‐objective linear programming model that solves the generation best‐mix problem for the existing power generation technologies; a nonlinear SOFC system model in which the economic cost and CO2 emissions by the SOFC system can be calculated; and the Queuing Multi‐Objective Optimizer (QMOO), a multi‐objective evolutionary algorithm (MOEA) developed at the EPFL in Switzerland as the overall optimizer of the combined power supply system. Thus, the framework integrates an evolutionary algorithm that is more suitable for handling nonlinearities with a calculus‐based method that is more efficient in solving linear programming problems. Simulation experiments show that the framework is successful in solving the stated problem. Moreover, the three components of the modularized framework can be interconnected through a platform‐independent model integration environment. As a result, the framework is flexible and scalable, and can potentially be modified and/or integrated with other models to study more complex problems. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
83.
K Suzuki T Furukawa Y Koyama T Sagawa M Nishimura M Yamanaka 《Canadian Metallurgical Quarterly》1998,32(5):819-825
The 32P-post-labelling assay for DNA adduct quantification gives the opportunity to examine endogenous exposure to DNA reactive compounds. Most human biomonitoring studies applied white blood cells (WBC) or cells obtained by broncho-alveolar lavages (BAL) as source of DNA, but still it is not clear what cell type represents the most reliable indicator for exposure to cigarette smoke-associated genotoxins. At first, we examined DNA adduct levels by means of nuclease P1 (NP1) enriched 32P-post-labelling in separated WBC subpopulations after in vitro incubations for 18 h with 10 microM benzo[a]pyrene (B[a]P). DNA adduct levels were highest in monocytes (10.7 +/- 2.9 adducts/10(8) nucleotides, n = 8), followed by lymphocytes (5.9 +/- 1.7, n = 8), and granulocytes (0.5 +/- 0.2, n = 8). Secondly, aromatic-DNA adduct levels were determined in BAL cells and WBC-subsets from (non-)smoking volunteers. In smoking individuals, adduct levels were in the ranking order: BAL cells (3.7 +/- 1.0, n = 5) > monocytes (2.0 +/- 0.5, n = 8) > or = lymphocytes (1.6 +/- 0.4, n = 8) > granulocytes (0.8 +/- 0.2, n = 8) by NP1-enrichment and monocytes (9.0 +/- 3.2, n = 5) > or = lymphocytes (8.0 +/- 2.1, n = 6) > granulocytes (2.1 +/- 0.3, n = 7) by butanol-enriched 32P-post-labelling. Aromatic-DNA adduct levels were significantly higher in WBC-subsets of smokers as compared with non-smokers, except for DNA adducts in granulocytes using butanol enrichment. Thirdly, dose-response relationships were investigated in mononuclear white blood cells (MNC, i.e. monocytes plus lymphocytes) and BAL-cells of a larger group of smoking individuals (n = 78). Adduct levels in MNC were related to daily exposure to cigarette-tar (r = 0.31, P < 0.01). Adduct levels in BAL cells seemed to be correlated with pack-years, but after correction for age this relationship was lost. Butanol extraction resulted in 5-6-fold higher DNA adduct levels in MNC, whereas butanol extraction of BAL-DNA of the same individuals yielded only 2-fold higher adduct levels. The two enrichment procedures of 32P-post-labelling were correlated in BAL cells (r = 0.86, P < 0.001, n = 12). We conclude that particularly MNC are good surrogates for the detection of smoking-related DNA adducts. 相似文献
84.
M Kohsaka N Fukuda R Kobayashi H Honma S Sakakibara E Koyama O Nakano H Matsubara 《Canadian Metallurgical Quarterly》1998,52(2):252-253
Subjective sleep feelings and motor activity were measured in seven healthy elderly subjects for 6 days. The subjects were exposed to bright light (6000 lux) for 30 min in the morning or instructed to sit in front of a desktop lighting device without light. The average level of motor activity during the night was significantly decreased in the bright light condition, compared with the controlled condition. However, daytime motor activity did not show significant differences between the two conditions. From these findings, even a short duration of morning bright light is effective in maintaining sleep without changing daytime activity. 相似文献
85.
A 71-year-old man was referred to us with diplopia, left peripheral facial nerve dysfunction, ataxic gait and dysesthesia of the extremities. Neurological examination revealed mild reduction of sensation to pinprick and light touch in the left dominant lower leg. His standing position was wide based, and he showed Romberg's sign. The patient also presented signs of left peripheral facial, bilateral abducent, and left oculomotor nerve dysfunction. Serum levels of CEA, CA 19-9, and proGRP were high. 67Gallium scintigraphy showed an accumulation of radioactivity at the hilum of the right lung, and the findings of bronchofiberscopy were compatible with the diagnosis of small cell lung cancer. Because the symptoms gradually worsened to the point that the patient could not move by himself, chemotherapy and radiotherapy were initiated 3 months after the onset of symptoms. While under chemotherapy, symptoms of neuropathy subsided and the patient was able to walk with the aid of a walking stick. Although all symptoms were indicative of carcinomatous neuropathy, no antineuronal antibodies were detected in the patient's serum by immunohistochemical techniques. However, because the lung cancer deteriorated gradually despite therapy, the patient died of respiratory failure. At autopsy, tumor metastases were found in the pericardium, left lung, both adrenal glands, right hilum lymph nodes, and mediasternal lymph nodes. No microscopic signs of metastases were found in the frontal, parietal, temporal, or occipital lobes, or in the basal ganglia, thalamus, midbrain, pons, cerebellar vermis and hemispheres, or upper medulla. Histopathologically, there was no degeneration of neuronal cell bodies in cerebellar or cervical dorsal root ganglia; however, almost total loss of myelinated fibers or variegated demyelination of myelinated fibers was observed in the anterior, lateral and posterior funiculus at both cervical segments of the spinal cord. The number of myelinated fibers was smaller in the 5th and 6th cervical left ventral roots. The reason why the patient's symptoms subsided during chemotherapy was probably a suppression of antineuronal antigen by chemotherapy and the repair of myelinated fibers. 相似文献
86.
Costimulation of T cells via B7-1 and B7-2 molecules on a tumor has been shown to be important for eliciting cell-mediated antitumor immunity. We studied the surface expression of B7-1 and B7-2 in 24 cases of gastric carcinoma from the primary locus, 20 cases of metastatic carcinoma from malignant ascites, 20 cases of benign gastric mucosa and 7 gastric carcinoma cell lines by two-color flow cytometry with mAb CD80 and CD86. The B7-1 and B7-2 molecules were expressed by 6 cell lines, and 1 cell line showed the predominant expression of B7-2 but not B7-1. Almost all patients with primary gastric carcinoma and benign gastric mucosa showed high levels of expression of the B7-1 and B7-2, revealing approximately 40%-60% positive cells. However, the percentage of B7-1-positive cells of poorly differentiated primary carcinomas was significantly lower than that of well-differentiated carcinoma and normal mucosa (P < 0.01). Furthermore, all of the metastatic carcinoma cells revealed consistently very low or undetectable levels of expression of the B7-1 molecule, only 8% (mean) of cells being positive, despite showing higher levels of B7-2 expression. Thus, it seems likely that decreased or deleted expression of B7-1 correlates with the grade of tumor differentiation, tumor progression and metastasis. These results suggest that the B7-1 molecule on the gastric carcinoma bearing CD80+CD86+ is abrogated during tumor invasion and/or metastasis, and the tumor finally acquires the CD80-CD86+ phenotype. Consequently, inadequate B7-1 costimulation may contribute to the escape of tumors from destruction by the host's immune system. 相似文献
87.
88.
Masahiro Nagae Yasunori Koyama Seita Yasutake Tetsuo Yoshio Kohei Oda 《Journal of the American Ceramic Society》2006,89(11):3550-3553
The corrosion behavior of sialon ceramics was investigated in supercritical water at 450°C under 45 MPa for 2–50 h. α-sialon exhibited better corrosion resistance than β-sialon and α/β-sialon. Pitting corrosion with the formation of corrosion products was observed in the case of β-sialon and α/β-sialon. By contrast, the corrosion behavior of α-sialon was characterized by uniform corrosion with the formation of corrosion products. The degree of strength deterioration was strongly dependent on the corrosion morphology. The bending strength of α-sialon after corrosion for 30 h was about 90% of its initial strength, while the strength of β-sialon decreased to 65% of its original strength. 相似文献
89.
90.