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排序方式: 共有841条查询结果,搜索用时 31 毫秒
81.
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
82.
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
83.
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
84.
85.
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
86.
87.
88.
Mizuki Ono Tsunehiro Ino Masato Koyama Akira Takashima Akira Nishiyama 《Solid-state electronics》2004,48(12):2191-2198
It is shown that propagation delay time in CMIS (complementary metal insulator semiconductor field effect transistor) inverters is strongly affected by dielectric constant nonuniformity in gate dielectrics caused by the phase separation in silicate films. Influences of such nonuniformity on load capacitance are studied by analytical calculations based on a physical model which takes polarization into account. It is newly found that load capacitances are affected by the phase separation in qualitatively different ways, depending on the average metal concentration of their dielectric films. An experimental result is compared with those calculations. Influences of such nonuniformity on current drivability are studied by 3-dimensional device simulations. It is also newly found that such nonuniformity affects load capacitance and current drivability in different ways, resulting in an increase in propagation delay time of CMIS inverters for all metal concentrations studied. An explanation of this phenomenon is given with physical considerations. 相似文献
89.
T Hebiguchi T Kato H Yoshino M Mizuno K Koyama 《Canadian Metallurgical Quarterly》1997,32(8):1149-1153
Four-week-old male Sprague-Dawley rats underwent a 90% small bowel resection. From the fourth day after surgery, they were divided into group 1 and 2, and pair-fed by elemental diets (0.8 kcal/mL, 50 mL/day) with L-arginine (n = 10) or L-glycine (n = 11) as an isonitrogenous and isoenergetic supplement for 3 weeks. They were compared with each other 3 weeks after surgery. A statistical analysis was performed using the unpaired Student's t test and the one-way factorial analysis of variance (ANOVA) using Bonferroni/Dunn multiple comparison test. A Pvalue of < .05 was considered significant. There were no significant differences between the two groups in food intake, body weight, tail length, residual ileal length, and plasma IGF-I level. However, the mean height of ileal villi in group 1 showed higher than that in group 2 (P < .01). Growth hormone-releasing hormone (GHRH) provocative tests (1 microg per rat, intravenously) showed the more significant elevation of growth hormone IGH) secretion in the arginine supplement group than that of glycine supplement group at 5 minutes (P < .05). There were no significant differences between basal levels of plasma rat GH in both groups. It is suggested that arginine has a possible significant role of GH secretion and intestinal mucosal growth after massive small bowel resection. 相似文献
90.
H. Tanaka N. Ishiguro T. Miyashita N. Yanagawa M. Sadamoto M. Koyama Y. Ashida N. Fukuda 《Solar Energy Materials & Solar Cells》1994,34(1-4)
The performance of a p-i buffer layer in pin amorphous silicon solar cell was improved by the “alternately repeating deposition and hydrogen plasma treatment method (ADHT)”. The optical bandgap of the a-Si film was increased by hydrogen plasma treatement. The wide optical bandgap and the high photoconductive a-Si:H films without carbon could be fabricated by the ADHT method. The conversion efficiency of the solar cell with a-Si:H buffer layer was almost the same as that using an a-SiC:H buffer layer. Second, the a-Si (ADHT) films were applied to the n-i buffer layer. The insertion of a-Si (ADHT) films between the i-layer and the n-layer was effective to improve the cell performance, especially the fill factor. With the use of high performance a-Si p-i and n-i buffer layer deposited by ADHT method, a cell conversion efficiency of 12.9% was obtained. 相似文献