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21.
K Yamada M Itoh N Fueki K Hirasawa N Suzuki K Kurata J Sato Y Morimatsu A Yagishita 《Canadian Metallurgical Quarterly》1993,25(5):435-441
The magnetic resonance examination was performed in 38 patients with severe cerebral palsy (CP; 15 males and 23 females) who had both motor delay (unable to move anywhere) and mental retardation (I. Q or D. Q below 30). Neuroimaging findings were compared with the CP type, etiology, and grade of understanding of language. Cranial magnetic resonance imagings (MRI) in CP were divided into five types. Type 1 : nine predominantly showed cyst-liked ventricles and periventricular hyperintensity on T2-weighted imaging (PVH) and only scarred basal ganglia and thalamus were visible. All suffered from neonatal asphyxia and the clinical type was rigospastic tetraplegia (RST). Type 2: eleven predominantly showed PVH and hyperintensity on T2-weighted (HT2) in basal ganglia and thalamus. All suffered from neonatal asphyxia and the clinical type was RST or rigospastic diplegia. Type 3: five showed PVH and three had cortical atrophy. All suffered from neonatal asphyxia and the clinical type was spastic diplegia. Type 4: four predominantly showed HT 2 in putamen and thalamus. Three had cortical atrophy. All suffered from neonatal asphyxia. The clinical type was athetotic CP (ATH). Type 5: nine predominantly showed HT 2 in globus pallidus. Four had cortical atrophy and two had hippocampal atrophy. All suffered from neonatal jaundice and the clinical type was ATH. All patients who suffered from neonatal asphyxia and spastic CP had MRI in PVH. All patients who suffered from neonatal asphyxia and ATH showed HT 2 in putamen and thalamus. Almost patients who suffered neonatal jaundice and ATH showed HT 2 in globus pallidus. With athetotic CP, cases with atrophy of the cerebral cortex or/and hippocampus were lower grade of understanding of language than no atrophy of both. The result of studies of MRI are in agreement with neuropathological findings. 相似文献
22.
Photonic transport network OAM technologies 总被引:3,自引:0,他引:3
The optical path concept was proposed to realize ubiquitous B-ISDN. It can make quantum leaps in both transmission capacity and cross-connect throughput simultaneously by exploiting WDM (wavelength division multiplexing) transmission and the wavelength routing capabilities of paths. Since the optical path is a new concept, new operation and management (OAM) systems and related technologies need to be developed before it can be fully utilized. This article discusses some of the key OAM-related issues and identifies the technical points necessary for future developments. The issues include optical path realization technologies, optical path accommodation design problems, a newly proposed optical transport network layer architecture, and the optical transport module for the network node interface 相似文献
23.
M Sato A Kondo S Otsuka H Tanabe N Matsuura K Hasegawa M Chin M Saiki 《Canadian Metallurgical Quarterly》1993,21(12):1143-1147
The authors report a rare case of a large cystic cervical neurinoma. A 45-year-old female was admitted to our clinic because of motor weakness of the right upper extremity, numbness of the right fingers and right posterior cervical pain. Metrizamide CT myelography demonstrated the outline of a low density mass. MRI showed a mass revealing low signal intensity on T1-weighted image, high signal intensity on T2-weighted image and marginal enhancement on contrast image with Gd-DTPA. The mass which was diagnosed as cystic tumor, was located in the intradural extramedullary space between C4 to C5 segments. After C4 through C5 laminectomy, the tumor was found to originate from the C5 anterior motor root. The tumor consisted mostly of a cystic part with a very thin solid compartment beneath the capsule. Postoperative course of the patient was uneventful. Although spinal neurinoma is one of the most common spinal tumors, an almost completely degenerated large cystic spinal neurinoma is extremely rare. MRI with Gd-DTPA was useful for the diagnosis of the cystic neurinoma by clearly enhancing the margin of the tumor. 相似文献
24.
Y. Ohshima H.S. Ahn M. Aoki S. Awa M. Fukushima H. Hayashii X.Q. Hu T.W. Hur S. Igarashi H. Ikeda H.C. Jeong K. Kaneyuki D.Y. Kim S.K. Kim A. Kuzmin M.H. Lee S. Noguchi A. Ochi H. Sagawa N. Sato N. Sugiyama K. Tamai T. Tanimori N. Toomi T.J. Wang K. Watanabe Y. Watanabe X.C. Zhong Y.C. Zhu 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,380(3):517-523
We studied the performance of a prototype electromagnetic calorimeter for the BELLE detector at the KEK proton synchrotron for an energy range of 0.25–3.5 GeV. The prototype consisted of an array of 6 × 5 CsI(Tl) crystals with 30 cm length (16.2 radiation lengths) and about 6 cm × 6 cm cross section. The scintillation light of each CsI(Tl) crystal was read out by two large-area PIN photodiodes and charge-sensitive preamplifiers attached at the rear face of the crystal. We measured the energy and position resolution for electrons and the e/π separation for two sets of matrix configurations: one corresponded to the center and the other to the edge of the barrel calorimeter. The overall performance measured by the test proves that the prototype calorimeter is satisfactory for the use in the BELLE detector. 相似文献
25.
26.
Ogi H. Nakamura N. Sato K. Hirao M. Uda S. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2003,50(5):553-560
This paper presents advanced techniques to determine all independent elastic-stiffness coefficients C/sub ij/, the associated internal friction Q/sub ij//sup -1/, and piezoelectric coefficients e/sub ij/ of monocrystal langasite (La/sub 3/Ga/sub 5/SiO/sub 14/) using a single rectangular parallelepiped specimen. Langasite's crystal structure belongs to the trigonal system with point group 32, and thus possesses six independent C/sub ij/, two e/sub ij/, and two dielectric coefficients /spl epsiv//sub ij/. All of the elastic and piezoelectric coefficients affect the mechanical resonance frequencies of the solid specimen, and measuring them very accurately permits one to determine the C/sub ij/ and e/sub ij/ with known density, dimensions, and e/sub ij/. We developed a piezoelectric tripod to support the specimen upward and measured the free-vibration resonance frequencies with minimum load from its own weight. This weak and stable acoustic coupling ensures accuracy of the frequency measurement better than 10/sup -5/, enough to determine the coefficients reliably. Our C/sub ij/ fall in the range of results measured with previous (conventional) methods. Our e/sub 11/ is smaller than the reported values by 1.2-13%, and e/sub 14/ is larger by 44-97%. For the internal friction measurement, we used a solenoid coil to vibrate the specimen without any contact. The longitudinal-wave internal friction considerably exceeds the shear-wave internal friction, which can be explained by phonon-phonon interactions. 相似文献
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28.
PURPOSE: Previous research has demonstrated that testosterone therapy causes a profound suppression of autoimmune disease in lacrimal glands of female mouse models of Sj?gren's syndrome. The aim of the present study was to determine whether other anabolic androgens, nonandrogenic steroids, or immunosuppressive agents might duplicate this hormonal effect. For comparative purposes, we also evaluated the influence of these various pharmacologic compounds on the tear volume, the magnitude of lymphocyte infiltration in the submandibular gland, and the extent of mucosal and peripheral lymphadenopathy. METHODS: Female MRL/MpJ-lpr/lpr mice were administered vehicle, steroids, or immunosuppressive compounds for 21 days after the onset of disease. Lacrimal glands and tears, as well as submandibular glands, spleens, and superior cervical and mesenteric lymph nodes were collected immediately before or after treatment and then processed for analysis. RESULTS: Our results showed that: (1) the immunosuppressive impact of testosterone on lymphocyte infiltration in lacrimal tissue was reproduced by the administration of 19-nortestosterone or cyclophosphamide, but not by therapy with 17 beta-estradiol, danazol, the experimental steroid Org 4094, cyclosporine A or dexamethasone; (2) treatment with testosterone, 19-nortestosterone, cyclophosphamide, or dexamethasone significantly reduced the extent of inflammation in salivary glands; (3) exposure to cyclophosphamide markedly diminished the size of lymphatic and splenic tissues, whereas glucocorticoid treatment only decreased the weight of superior cervical lymph nodes; and (4) administration of 17 beta-estradiol, Org 4094, or dexamethasone led to a significant decrease in tear volume. CONCLUSIONS: Overall, these results demonstrate that androgen or cyclophosphamide therapy may successfully ameliorate autoimmune expression in lacrimal and salivary glands of a female mouse model of Sj?gren's syndrome. 相似文献
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Some work is so complicated and unsteady that it is not possible to use automatic robots, such as FA robots. In such a case, a teleoperated manipulation system is applied. In this research, the authors aim at a reduction in the operator's physical and mental burdens. An artificially intelligent manipulator system has been developed with nonsymmetric and redundant master-slave. This system has five features: (1) a polar coordinates master arm; (2) a highly operational articulated slave arm with 7 degrees of freedom; (3) a nonsymmetric configuration and different degrees of freedom master-slave control; (4) an expert system; and (5) a new master-slave control motion, which makes the operator's task easier with automatic force/position control. The system was experimentally produced and its performance tested and evaluated. A qualitative evaluation was carried out by conducting a comparative test on the conventional master-slave control and the new master-slave control. It was found to be effective in reducing operating time, as well as work-induced fatigue. 相似文献