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排序方式: 共有620条查询结果,搜索用时 12 毫秒
61.
62.
S Nagaoka H Arai N Iwamoto J Ohwada Y Ichimiya M Nakamura R Inoue 《Canadian Metallurgical Quarterly》1995,19(8):1251-1261
1. An autopsy case of frontotemporal dementia with onset at the early age of 28 years is reported. 2. The neuropathological features consisted of limited, knife-like frontotemporal atrophy with severe neuronal loss, spongiform change and gliosis, which is compatible with the frontotemporal dementia. 3. Biochemical determinations disclosed that biogenic amines and their metabolites, predominant in the dopaminergic markers, were depleted in the damaged regions. 4. Since biochemical data in frontotemporal dementia are few in previous studies, it will be determined whether these biochemical changes are characteristic for the juvenile type of frontotemporal dementia or not. 相似文献
63.
A Hino M Fujimoto T Yamaki Y Iwamoto T Katsumori 《Canadian Metallurgical Quarterly》1998,29(12):2517-2521
BACKGROUND and PURPOSE: Neuroradiological investigations do not disclose a source of bleeding in some patients with spontaneous subcortical hemorrhage. These patients may harbor undetected vascular malformations and may be at risk of rebleeding in the future. We investigated patients with subcortical hemorrhage with use of repeat angiography and MRI to determine the incidence of occult vascular malformations and the risk of bleeding during follow-up. METHODS: We reviewed a consecutive series of 137 patients with subcortical hemorrhage during a 10-year period (June 1987 through June 1997). If the patient was <65 years old and the first angiogram and/or MRI did not show a source of bleeding, repeat angiography was recommended. All angiographic and MRI studies were reviewed. The relationship between the identified bleeding source and clinical variables such as patient age, sex, and history of hypertension and the size and location of the hematoma were examined. RESULTS: One hundred seven patients (78%) underwent angiography on admission, 10 (7%) had immediate surgery for hematoma without angiography, and 20 (15%) had neither angiography nor surgery. Overall, an etiology for the hemorrhage was found in 55 cases (40%). Vascular malformations were common in young patients without preexisting hypertension. A second angiogram was obtained in 22 patients, and 4 arteriovenous malformations were demonstrated. Rebleeding at the site of the initial hemorrhage was not observed after a mean follow-up of 68 months. CONCLUSIONS: Angiography performed acutely after hemorrhage may not demonstrate vascular malformations. Consideration should be given to repeat angiography in patients who do not have a specific cause for hemorrhage. 相似文献
64.
Influence of Slurry Flocculation on the Character and Compaction of Spray-Dried Silicon Nitride Granules 总被引:1,自引:0,他引:1
Hideo Takahashi Nobuhiro Shinohara Masataro Okumiya Keizo Uematsu Tsubaki JunIchiro Yuji Iwamoto Hidehiro Kamiya 《Journal of the American Ceramic Society》1995,78(4):903-908
The effect of slurry flocculation on the characteristics of silicon nitride granules prepared by the spray drying process is investigated. The flocculation state of an aqueous silicon nitride slurry is controlled by adding nitric acid and evaluated as a function of pH. Dense and hard silicon nitride granules result from a well-dispersed slurry having a high pH (e.g., 10.8). These hard granules retain their shape in green compacts and form detrimental defects. Lowering the pH of the slurry to a certain value (e.g., pH 7.9) results in slurry flocculation. Granules prepared from this flocculated slurry have low density and low diametral compression strength and contribute to the elimination of large pores in green compacts. 相似文献
65.
T Yamaki N Murakami Y Iwamoto T Sakakibara N Kobori S Ueda T Kikuchi Y Uwahodo 《Canadian Metallurgical Quarterly》1997,752(1-2):151-160
Enantiomer separations of various acidic racemates were performed by capillary electrophoresis (CE) using a commercial cationic beta-cyclodextrin (beta-CD), quaternary ammonium beta-CD (QA-beta-CD), and a commercial amphoteric beta-CD (AM-beta-CD) as chiral selectors. Eleven acidic racemates were successfully separated using QA-beta-CD by changing the CD concentration and the buffer pH. These enantiomer separations were compared with the results using five neutral CD derivatives. Although most racemates were separated with some of the neutral CDs, relatively high CD concentrations were required to obtain baseline separations. In contrast, when QA-beta-CD was employed, the enantiomer separations were successful at low concentrations below 5 mM. Enantiomers of five acidic racemates and ten dansylated amino acids (Dns-amino acids) were separated using AM-beta-CD. Although the baseline separation of racemic 4-chloromandelic acid was not achieved with either QA-beta-CD or five neutral CDs, AM-beta-CD showed complete resolution. Furthermore, the simultaneous enantiomer separation of eight Dns-amino acids was also achieved with AM-beta-CD. Both QA-beta-CD and AM-beta-CD were analyzed by CE and mass spectrometry (MS) in order to identify their compositions because they consisted of a mixture having different degrees of substitution. QA-beta-CD consisted of six components having from one to six quaternary ammonium groups. The composition of AM-beta-CD, however, was very complicated and could not be identified. 相似文献
66.
K Yoshikawa K Iwamoto E Sugimoto Y Takanashi K Nakajima 《Canadian Metallurgical Quarterly》1997,37(6):500-505
We report a 42-year-old left-handed woman with congenital right hemiparesis and bilateral mirror movements in the hands. She had a porencephaly of the left hemisphere and the brain MRI demonstrated cortical and subcortical defect of the left hemisphere from Brodmann's area 6 to 40 including the left motor cortex. By electrical stimulation of the left median nerve at the wrist, N20 of the somatosensory evoked potential was recorded in the right postcentral gyrus by using the dipole tracing method. Long-loop reflexes from the bilateral thenar muscles were recorded and their latencies were almost the same. The stimulation of the right median nerve did not evoke N20, nor long-loop reflex. These electrophysiological findings suggest that the reorganization of the motor system made the right motor cortex to innervate bilateral hands, and caused bilateral mirror movements. In other words, the mirror movements managed to relieve the paralysis of the right hand though the damage of the left motor cortex was present. In the previous literature we are able to find hypotheses regarding the mechanism of mirror movements in congenital hemiparesis. Here we discussed about the reorganization of the motor system in the damaged brain. 相似文献
67.
“Tracing the power flow of electricity” is a concept that has become the focus of attention recently, as the deregulation or the liberalization of the electric power market proceeds. Although a number of methods, such as “tracing method by power flow contribution,” have already been published, reactive power contribution has been little studied to date. However, applying “tracing the power flow of electricity” to ancillary service, for example compensation of reactive power, is very important. In this paper, we focus on line flows and static capacitors in particular, and study how to deal with the problem. We perform a computer simulation using a simple system and show the tracing results. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(1): 33–43, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/ eej.20118 相似文献
68.
H Higaki T Murakami Y Nakanishi H Miura T Mawatari Y Iwamoto 《Canadian Metallurgical Quarterly》1998,212(5):337-346
This paper describes the process of involving health professions students in research in rural primary care and how their research has contributed to the development and expansion of a rural community health center. Since 1978 over 400 students have completed rotations at the center, and more than 200 have been health profession students, including medical, nursing, physician assistant, pharmacy, and health administration students. A total of 96 research projects were completed. These projects lie in two main areas: medical services and community outreach. Those related to medical services include measures of access to care, quality of care audits, clinical guideline development, practice patterns, prevalence studies, and qualitative research. Projects focusing on community outreach include community surveys, screening follow-ups, program evaluation, and program development. Principles that guide the selection and conduct of research projects include: Projects should be directly related to important work of the practice and reflect an interest of the student; projects are structured to include some or all of the following: literature search, data analysis, a visual display of quantitative information (table or graph), and application of relevant statistical tools; the student has a project supervisor; the student is a participant rather than an independent investigator; and a research flow sheet is used to orient students and NRHA staff to the larger research effort. Students are expected to present results, conclusions and recommendations to an appropriate group. Student research has made a significant contribution to both practice activities and practice policies. 相似文献
69.
S Nishida K Kuroko T Hoshino T Iwamoto C Shirai 《Canadian Metallurgical Quarterly》1998,44(8):599-601
There are few reports of the sonographic appearance of Meckel's diverticulum. We present a case of torsion of a Meckel's diverticulum that was suggested by sonography and confirmed pathologically. We discuss the sonographic differential diagnosis, which includes acute appendicitis, enteric duplication cyst and intestinal volvulus. 相似文献
70.
We examined the concentration of ethylene oxide in bone allografts after gas sterilization. Chips of the human femoral head were investigated. Residual gas concentration was determined by gas chromatography after the bone chips had been subjected to defatting and freeze-drying, followed by ethylene oxide gas sterilization. Bones were prepared in various ways in an attempt to reduce the concentration of residual ethylene oxide. The concentration was higher when gas sterilization was performed before freeze-drying than when it was done afterwards. An experiment performed with fibroblasts showed the high toxicity of residual ethylene oxide in bone chips, even when the concentration was very low. The growth of fibroblast was reduced more in medium which had been shaken with bones sterilized with ethylene oxide before freeze-drying than in medium which had been shaken with bones sterilized after freeze-drying. The higher residual ethylene oxide concentrations resulted in a decrease in fibroblastic culture activity. Our experiment showed the importance of reducing the residual ethylene oxide gas concentration. Defatting and freeze-drying result in lower residual ethylene oxide concentrations. 相似文献