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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   
54.
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   
55.
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   
56.
“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   
57.
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   
58.
The authors have developed a new process as an alternative to sulfuric peroxide mixture (SPM) cleaning of Si wafers. This process, vapor ozone strip (VOS), uses ozone and vaporized water, significantly reducing any effect on environment, health and safety. The process is more effective than ozone water immersion, because high concentration ozone gas and high temperature water can be used simultaneously. Also, the process uses the highly reactive OH* radical species. The VOS process is able to strip photoresist at a higher rate than other techniques using ozone. Ion implanted photoresist and etched photoresist can be stripped. VOS has demonstrated equivalent performance to SPM in electrical reliability testing.  相似文献   
59.
The development of different muscles and adipose tissues during growth was investigated in commercial Japanese Black (JB) cattle and compared with breeds of the largest variation to be found in Europe. Animals, reared under typical conditions for Japanese and European beef production systems, gained similar body weights but different carcass composition at 24 months of age. The carcass of JB contained more adipose tissue and the least proportion of muscle. The longissimus muscle of JB developed extraordinary amounts of 23.3% intramuscular fat (IMF) at 24 months of age, compared from 0.6% to 4.7% in European breeds. The relationships between IMF content in the longissimus muscle and different adipose tissue weights indicate that a large amount of “waste fat” is accreted with every percent of IMF. However in JB, the good ability of IMF deposition is associated with relatively least development of “waste fat”, as a result of unique breed characteristics combined with special feeding system.  相似文献   
60.
The preparation and dyeing properties of new monoazo dyes prepared from aminonophthothiazole derivatives using a tertiary amine as the coupling component. The fibres considered are: polyester, cellulose acetate, nylon 6 and acrylic.  相似文献   
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