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61.
A self-administered questionnaire study of 333 workers (male 253, female 80) in a manufacturing company was carried out one month after informing the workers of the results of their medical checkups in 1993. The questionnaire included several items such as recalled abnormal findings of health examination and ways of overcoming the abnormal findings, recalled results of their medical checkups in 1992, self-confidence in their recollection of the results, and the usefulness of medical checkups. The following were investigated: the relationship between actual as well as recalled results of medical checkups in 1992 and the recollection of them after one year, the effects of examinations after medical checkups in 1992 on their recollection of the checkup results after one year, the effects of actual as well as recalled 1992 checkup results on the recollection of the results one month after informing the workers of the results of their medical checkups in 1993, assurance of correct recollection of the results, the relationship between the usefulness of medical checkups, explanation of abnormal findings and the percentage of correct answers to the results of medical checkups in 1993 one month after informing the workers of their results. It was found that the percentage of correct answers to the results after one year was significantly lower than that after one month in 1992. The rate decreased with the increase in the number of abnormal items in medical checkups. Moreover, the rate also decreased when the results were abnormal. Further examinations in addition to the medical checkups influenced their recollection somewhat after one year. The results that the workers still remembered in 1992 had a stronger effect on their recalling the results one month after informing them in 1993 than the actual results in 1992. The workers' confidence in their recollection of the results was untrustworthy in the same way as their recollection of the results, and they were not able to maintain the recollection of the correct results, although many of the workers realized the usefulness of the medical checkups. Our results suggest that explanation of abnormal medical findings in 1993 was effective because the percentage of partial concordance between actual and recalled results was much higher in the workers who received the explanation than in the workers who did not receive it. 相似文献
62.
63.
M Adachi A Hayashi N Ohkoshi H Nagata H Mizusawa S Shoji F Tabei A Matsumura 《Canadian Metallurgical Quarterly》1995,34(8):806-810
A 67-year-old woman with a one-year history of tinnitus and headache had multiple cranial nerve palsies of V, VII, VIII, IX, X, XI and spastic paraparesis. She also had a secretory otitis media. Gd-DTPA-enhanced magnetic resonance imaging (MRI) revealed hypertrophy of the dura of the posterior fossa and spinal epidural mass which extended from C7 to T10. A biopsy of the epidural mass showed chronic granulomatous change. These lesions were completely cured with administration of antibiotics. We believe this case of double-lesion of hypertrophic cranial pachymeningitis and spinal epidural granulomatous lesion originated from a bacterial infection secondary to the secretory otitis media. 相似文献
64.
Miyuki Hayashi Masahiro Susa Toshio Maruyama Kazuhiro Nagata 《Journal of Electronic Materials》1995,24(8):983-989
The annealing of 20CaO·20SiO2·7Fe2O3·6FeO glasses at 973K in vacuo produced clusters of iron oxide, the shape of which was nearly spherical and the diameter distributed in the narrow range 25–115Å. The phase of clusters was identified to be Fe3+(Fe3+ poststagger|1.30Fe2+ poststagger|0.55V0.15)·O4 in the inverse spinel structure based upon the Mössbauer spectra and x-ray diffraction profiles. The clusters exhibited superparamagnetism and their effective anisotropy energy constant was inversely proportional to the cluster diameter. The magnetization of the glasses measured by a vibrating sample magnetometer was 7.2 × 10-6 Wbmkg-1 at 10 kOe at room temperature and smaller than the value calculated assuming that the whole clusters have superparamagnetism. These results suggest the pinning of spins near the cluster surface. 相似文献
65.
66.
Girija EK Yokogawa Y Nagata F 《Journal of materials science. Materials in medicine》2004,15(5):593-599
Recently, we reported the formation of bone-like apatite on collagen fibrils by biomimetic method. Compounds containing carboxyl moieties are believed to be effective in the formation of apatite. Polyacrylic acid [-CH2CH(COOH)-]n (PAAc) is widely used in dentistry. In the present study, the effect of PAAc in the formation of apatite from revised simulated body fluid (R-SBF) on collagen fibrils was studied. Two different experimental approaches were tried to study the effect of PAAc present in the collagen and in the R-SBF solution. In the first, collagen gel was soaked with 1 mg/ml PAAc (molecular weights 25000 and 100000) for the time intervals of 30 min and 6 h. The gels were then dried in air and incubated in R-SBF. Characterization of the precipitates formed on the collagen fibrils in gel showed that the formation of apatite was inhibited when soaked in PAAc for 6 h. In the second experiment, when PAAc (0.1 and 1.0 mg/ml) was mixed with R-SBF the microstructure of the precipitates formed on collagen fibrils was affected partially. Hence, it is confirmed that the presence of PAAc in the biomimetic environment of collagen affects the mineralization of apatite. 相似文献
67.
T.?IntratorEmail author M.?Nagata A.?Hoffman H.?Guo L.?Steinhauer D.?Ryutov R.?Miller S.?Okada 《Journal of Fusion Energy》2004,23(3):175-182
Scientists from research institutions in the United States of America and Japan attended a USA Department of Energy sponsored joint international workshop on the subject of Compact Toroids (CT) in Santa Fe, NM, USA in September 2004. We outline here a summary of the topics that were discussed, some of the implications, and new directions that are likely to follow from this research. Experimental, theoretical and computational results were presented. The experimental devices and concepts, along with the theory and computational models comprise investigations of fundamental plasma physics, fusion science, and approaches to fusion energy that require magnetized plasmas. 相似文献
68.
A new integrated-injection-logic circuit which consists of multiple (m) layers of I2L circuit blocks and operates with an extremely low power dissipation is discussed. The same logic function is realised with m-times less power than a conventional I2L circuit. 相似文献
69.
In emulsion polymerization, the Smith and Ewart theory gives about two or three times the number of polymer particles obtained by experiment. In this paper, a reaction model is proposed which, from the standpoint of reactor design, can give an adequate explanation of the whole course of an emulsion polymerization of monomer highly insoluble in water. Among other things, the generating process of polymer particles is examined in detail. It is demonstrated experimentally that a new parameter proposed here, which represents the degree of difficulty of monomer initiation in micelles, is indispensable in explaining that process. Also confirmed is that monomer initiation takes place more easily in polymer particles than in micelles. According to the new model, the progress of polymerization, i.e., monomer conversion, the number of the polymer particles, and properties of polymer thus produced can be estimated with satisfactory accuracy. Furthermore, approximate equations are derived for easier estimation. 相似文献
70.
The motility pattern of mammalian spermatozoa changes during migration in the female genital tract and during incubation in vitro. This change in motility is termed hyperactivation. Hyperactivated spermatozoa swim vigorously in 'whiplash', 'figure-8' or 'small circle' trajectories. In this study, a quantitative analysis was carried out of the changes in the motility pattern of hamster spermatozoa during incubation to investigate the mechanism regulating hyperactivation. In the culture system used in this study, hyperactivation occurred 4 h after incubation. Several parameters in the analysis of sperm movement pattern were examined. Curvilinear velocity, average path velocity and straightness abruptly increased between 2 and 4 h. However, linearity, amplitude of lateral head displacement, beat cross frequency and average wavelength gradually changed with time. In the analysis of flagellar bending, the bend angles were measured after dividing images of the flagellum into short lengths. Flagellar bending changed in different manners in each region during incubation. The asymmetry in the direction of the curve of the head gradually increased with time in the first half of the flagellum. The flexibility, which was determined using the amplitude of bending and the rate of change in bend angles, abruptly decreased between 10 min and 1 h, and then increased between 2 and 4 h in the first half of flagellum. These results indicate that complex physiological changes occur before hyperactivation. 相似文献