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1.
K. Arima Minako Nakamura Nobuhiko Sunohara Masafumi Ogawa Midori Anno Yoko Izumiyama Shigeo Hirai Kazuhiko Ikeda 《Acta neuropathologica》1997,93(6):558-566
Coiled bodies and interfascicular threads are conspicuous white matter abnormalities of brains of patients with progressive
supranuclear palsy (PSP). Both structures are argyrophilic and immunoreactive for the microtubule-binding protein tau. This
report concerns the ultrastructural localization of interfascicular threads and their relationship to coiled bodies in five
PSP patients. We showed for the first time that abnormal tubules with a 13- to 15-nm diameter and fuzzy outer contours were
the common structures of coiled bodies in the oligodendroglial perikarya and of interfascicular threads. Moreover, the tubules
were immunolabeled by anti-tau antibodies. The abnormal tau-positive tubules of interfascicular threads were located in the
inner loop of the myelin sheath. Our study further indicated that the thread-like structures in the white matter comprised,
at least in part, oligodendroglial processes, and that they were also present in gray matter. We consider that the formation
of coiled bodies in the perikarya and of interfascicular threads represents a common cytoskeletal abnormality of the oligodendroglia
of PSP patients. Moreover, even though the white matter alterations of PSP resemble those of corticobasal degeneration, there
are certain ultrastructural differences in the abnormal oligodendroglial tubules of the two diseases.
Received: 4 October 1996 / Accepted: 6 December 1996 相似文献
2.
A technique for estimation of the longitudinal relaxation time of a large homogeneous object with an acquisition time of 4 s or less was developed by combining spatially selective rf tagging pulses with a T1-weighted magnetization-prepared gradient-echo sequence. Multiple 5-mm-wide tagged areas are laid orthogonal to the imaging section of interest. The contrast between each tag and the untagged regions differs because each tag is produced at a different time. The T1 value is determined from the nulling time at which tagged and untagged areas have no contrast. 相似文献
3.
Dr. Ernst Graser 《Naunyn-Schmiedeberg's archives of pharmacology》1883,17(5):329-362
Ohne ZusammenfassungDie folgenden Experimente wurden in Gemeinschaft mit Herrn Dr. Hölzke, früherem I. Assistenten an der Erlanger Augenklinik, angestellt, und hat derselbe im Archiv für Ophthalmologie bereits eine kurze Mittheilung über die Resultate gegeben. 相似文献
4.
Yoshitada?SakaiEmail author Shigehisa?Wada Hiroshi?Matsumoto Tomoko?Suyama Osamu?Ohno Izumi?Anno 《Journal of artificial organs》2003,6(3):197-204
It is very important to observe the concentrations and flow patterns of blood through a dialyzer to evaluate its function and to obtain the most appropriate design. We established a visualization method for the blood flow pattern in a dialyzer using X-ray computed tomography, and investigated the so-called internal filtration phenomenon. The results obtained were as follows: (1) The influence of 5% BaSO4, which was added to the blood as a contrast medium, on the filtration rate of the dialyzer was minimal. (2) The relationship between the concentration of BaSO4 and the Hounsfield unit value was expressed by linear regression. (3) Hounsfield unit values increased massively just after blood entered the dialyzer and peak values increased with dialysate perfusion under the following conditions: the dialyzer (BS-1.6UL, polysulfone hollow fibers) was used, and bovine blood with 5% BaSO4 added was used at a blood flow rate of 200ml/min. The dialysate flow rate was 500ml/min and the slice thickness of X-ray computed tomography was 1–10mm. (4) It was observed that blood flowed slightly faster in the center than the peripheral portion of the dialyzer, when the flow pattern was followed after pulse injection of blood containing 20% BaSO4 into the dialyzer. It was concluded that this method could possibly be utilized not only qualitatively but also quantitatively for observation of the real state of blood flow and in designing dialyzers. 相似文献
5.
Eric E Wickel Joey C Eisenmann Robert P Pangrazi Susan V Graser Anders Raustorp L M Tomson Thomas F Cuddihy 《American journal of human biology》2007,19(4):537-543
The purpose of this study was to examine the day-to-day variability in pedometer-assessed physical activity (steps/day). A total of 1,443 children aged 6-12 years from the United States (195 boys, 254 girls), Sweden (257 boys, 252 girls), and Australia (229 boys, 256 girls) wore a pedometer for 4 consecutive weekdays. Repeated measures analysis of variance was used to examine daily differences in steps/day and the coefficient of variation (CV) was calculated for each individual to describe the day-to-day variability. Overall, mean steps/day were higher among boys (14,698 +/- 3,373 steps/day) than girls (12,086 +/- 2,929 steps/day). Significant differences were found between the 4 monitoring days for the entire sample; however, the absolute mean differences were small (55-958 steps) with an overall effect size of 0.01. This trend was apparent regardless of age, gender, and country. Individual CVs ranged from approximately 2 to 88% and the overall mean CV approximated 22%. An age-related increase in the mean CV was observed between 6- and 12-year-old children. The age x gender x country interaction was not significant (P > 0.05). These findings have implications toward the proper design, analysis, and interpretation of studies regarding physical activity among children. Beyond this aspect, our results lend insight into potential age-related biological mechanisms that may also influence daily levels and patterns of physical activity. 相似文献
6.
Lin Y Kawamura T Anno T Ichihara Y Ohta T Saito M Fujioka Y Kimura M Okada T Kuwayama Y Wakai K Ohno Y 《Environmental health and preventive medicine》1999,4(3):117-121
It is well known that physical exercise can reduce coronary risk factors. But how an aerobic exercise modifies coronary risk
factors in relation to severity and physical fitness is still controversial.
Fifty-four middle-aged women (mean age, 55 years) completed a 6-month on-site and home-based anaerobic threshold-level exercise
program. The changes in coronary risk factor profiles were observed during the pre-intervention and intervention periods.
Before the intervention (during control period), most coronary risk factors showed a rather unfavorable trend. After the program,
their mean body weight decreased from 56.7 to 55.7 kg (p>0.05) and the proportion of body fat from 30.9 to 27.9% (p>0.05)
without any reduction in lean body mass. Systolic blood pressure (SBP) decreased from 129.0 to 125.0 mm Hg (p>0.05) and diastolic
blood pressure from 79.5 to 76.6 mm Hg (p>0.05). Fasting plasma glucose (FPG) declined from 109.6 to 103.4 mg/dl (p>0.05).
Changes in SBP and FPG were most remarkable in their respective worst tertile. Serum lipids improved only modestly. Maximum
oxygen uptake increased from 23.6 to 26.1 ml/kg/min (p>0.01). However, no significant correlations were found between changes
in coronary risk factors and those in physical fitness. We conclude that the 6-month aerobic exercise program would modify
women’s coronary risk factors depending on their initial values, probably independently of the changes in physical fitness. 相似文献
7.
8.
Mori K Saida Y Kuramoto K Anno I Yoshioka H Irie T Itai Y 《The Journal of cardiovascular surgery》2000,41(3):463-467
Mycotic aneurysms of the subclavian artery are rare. This report describes an experience of 2 rare cases in which transcatheter embolization with metallic coils was performed for the management of these lesions alternative to surgery. Two patients who had been treated with chemotherapy for malignant neoplasms were diagnosed as having mycotic aneurysms of the left subclavian artery. The causes of these lesions were presumed to be the invasion of the arterial wall by the pulmonary abscess in case 1, and wound infection after placement of the reservoir for intraarterial chemotherapy in case 2. In both cases, proximal and distal sites of the aneurysm were embolized with metallic coils. In case 1, the vertebral artery was also embolized with Guglielmi detachable coils to avoid retrograde blood flow. Both aneurysms were completely occluded by a single embolization. In case 1, although weakness and paresthesia of the left hand remained, lethal hemoptysis due to aneurysmal fistulization to the lung parenchyma ceased. In case 2, no neurological deficit except for mild paresthesia in the left thumb had been observed. Both patients died of primary disease 10 and 5 months after the procedure. Transcatheter embolization is technically feasible and effective enough to treat the mycotic aneurysm of the subclavian artery even in the situation in which the surgical option seems to be difficult or risky. 相似文献
9.
Manuel Grossgasteiger Cand. Med. Maximilian D. Hien M.D. Bastian Graser M.Sc. Helmut Rauch M.D. Matthias Gondan Ph.D. Johann Motsch M.D. Christian Rosendal M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(6):672-681
Transesophageal echocardiography is recommended to monitor left ventricular (LV) size and function in various operations. Generally, two‐dimensional (2D) methods are applied intraoperatively. The aim of this study was to compare the accuracy and feasibility of 6 commonly used 2D methods to assess LV function during surgery. LV function in 120 consecutive patients was evaluated. Real time three‐dimensional transesophageal echocardiograpy (3DTEE) served as reference. End‐diastolic and end‐systolic volumes and ejection fraction (EF) were analyzed with Simpson's method of discs (monoplane [MP] and biplane [BP]), eyeball method, Teichholz' method, and speckle tracking (ST) methods. Furthermore, fractional area change (FAC) and peak systolic pressure rise (dP/dt) were determined. Each 2D method was evaluated regarding correlation and agreement with 3DE, intra‐ and interobserver variability and the time required for evaluation. Simpson BP showed the strongest correlation and best agreement with 3DE for EF (limits of agreement 3.7 ± 11.6%) and volumes. Simpson MP showed similar agreement with 3DE compared to ST (2.8 ± 14.5% vs. 2.0 ± 15.3% and 3.8 ± 14.4% vs. 1.9 ± 15.6%, respectively). Both the eyeball method and Teichholz' method showed wide limits of agreement (?1.5 ± 18.2% and 5.2 ± 22.1%, respectively). DP/dt did not correlate with 3DE. FAC and ST FAC showed similar agreement. Application of 3DE (429 ± 108 seconds) took the longest time, and the eyeball method took the shortest time (8 ± 5 seconds) for analysis. Simpson BP is the most accurate intraoperative 2D method to evaluate LV function, followed by long‐axis MP evaluations. Short‐axis views were less accurate but may be suited for monitoring. We do not recommend using dP/dt. 相似文献
10.