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71.
K Harada J Yoshida T Wakabayashi H Okabe K Sugita 《Canadian Metallurgical Quarterly》1995,137(1-2):102-105
We treated a 1-year-old female with a hypothalamic hamartoma and precocious puberty with leuprolide acetate depot, a super long-acting hormone-releasing hormone analogue (Tap-144-SR; [D-Leu6-[des-Gly10-NH2] LH-RH ethylamide acetate). The infant's major symptoms were genital bleeding and gynaecomastia. The LH-RH analogue (30 micrograms/kg) was injected subcutaneously once every 4 weeks. Clinical and laboratory manifestations of precocious puberty showed marked improvement. A follow-up after 16 months of treatment, the size of the tumour decreased significantly and remained unchanged for 2 years of further follow-up. To the best of our knowledge, this is the first hypothalamic hamartoma case in whom a decrease of tumour size under treatment with LH-RH analogue has been documented. But, because diagnosis of hamartoma is only based on neuroradiological and not on histological examinations, the possibility of a gangliocytoma cannot be excluded with certainty. 相似文献
72.
73.
K Saku Y Takeda T Nii K Shirai M Okabe T Ohta K Arakawa 《Canadian Metallurgical Quarterly》1997,48(12):1067-1071
The authors report a patient with silent dissecting aortic aneurysm in whom three-dimensional spiral computed tomography (CT) angiography (3D-CTA) provided important imaging data. Images obtained by 3D-CTA were compared with the results of both conventional angiography and CT. They conclude that 3D-CTA was a powerful diagnostic modality for this patient, in addition to conventional CT and angiography. 相似文献
74.
Water-immersion stress for 7, 14, or 20 hr consistently induced linear or punctate stress ulcers (mucosal erosions) in the corpus of the stomach in intact rats. When the pylorus of the stomach had been ligated prior to stressing, the stress ulcers changed their morphological feature (mainly punctate and in one place elongated) and location (both in corpus and antrum). Histologically, the stress ulcer developed in the proximal antrum of pylorus ligated rats and penetrated into the muscularis mucosa. Sodium bicarbonate, chlorpromazine, hexamethonium, atropine, metiamide, and bilateral vagotomy markedly inhibited the stress ulcers which developed in the pylorus-ligated rats. Phentolamine and propranolol hardly affected the development of stress ulcers. Amylopectine evoked a new type of stress ulcer in the corpus when it was given to the pylorus-ligated rats. 相似文献
75.
Kushibiki J Arakawa M Ohashi Y Okabe R 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2005,52(7):1152-1160
We developed experimental procedures to evaluate glass materials using the line-focus-beam ultrasonic-material-characterization (LFB-UMC) system. We prepared 28 specimens of a commercial borosilicate glass from random lots, and measured the velocities of leaky-surface acoustic waves (LSAWs) and leaky-surface-skimming compressional waves (LSSCWs), VLSAW and VLSSCW, using V(z) curve measurements at 225 MHz and 23 degrees C. The velocities for VLSAW ranged from 3121.83 m/s to 3149.77 m/s, with a maximum deviation of 27.94 m/s. The velocities for VLSSCW ranged from 5547.7 m/s to 5585.0 m/s, with a maximum deviation of 37.3 m/s. To investigate these observed variations in VLSAW and VLSSCW, we measured the bulk acoustic wave (BAW) properties, viz., longitudinal and shear velocities, then the densities and the chemical compositions of 8 of the 28 specimens. The LFB-UMC measurements confirmed that decreases in VLSAW and VLSSCW occur mainly with the B2O3 dopant concentrations, corresponding to the decrease of shear-wave and longitudinal-wave velocities that are caused by the decrease of the stiffness constants c44 and c11, respectively, rather than with decreased densities. The sensitivities are -6.36 x 10(-2) wt%/(m/s) for VLSAW and -4.87 x 10(-2) wt%/(m/s) for VLSSCW. This demonstrates that the LFB-UMC system is effective for evaluating glass materials and controlling production processes, by analyzing variations in chemical composition through the super-accurate velocity measurements of LSAWs and LSSCWs. 相似文献
76.
Woodceramics are new porous carbon materials obtained by carbonizing wood or woody material impregnated with thermosetting resin such as phenol resin in a vacuum furnace. During the carbonizing process, thermosetting resin changes into glassy carbon, which has superior corrosion resistance and mechanical strength, reinforces the material and suppresses the fissures and warps (caused by the porous structure specific to wood) that develop during thermoforming. The dimension, weight decrease rate, and electrical characteristics depend on the thermoforming temperature. The manufacturing method of Woodceramics is introduced in this paper and various industrial uses, such as electromagnetic shields, are discussed. 相似文献
77.
A central bronchogenic cyst was excised thoracoscopically from a 44-year-old woman in whom a tumor had been pointed out in the left upper posterior mediastinum at a screening examination. Since the tumor was diagnosed to be benign, only conservative follow-up was undertaken, but the patient consulted our department desiring active therapy. On the basis of the chest CT and MRI findings a bronchogenic cyst was diagnosed. Under general anesthesia and mechanical ventilation of one lung, the thoracoscope was inserted into the thoracic cavity revealing in the left upper posterior mediastinum a cyst which was excised thoracoscopically. While coagulation was performed gingerly with an electric scalpel, the tumor was detached sharply and bluntly with a pair of scissors. The postoperative course was uneventful with little wound pain or scar formation. Hitherto bronchogenic cysts have been treated by resection after thoracotomy. Although this is an easy procedure, a relatively large operative scar is left and considerable wound pain may develop. In contrast, thoracoscopic treatment is characterized by minimal surgical invasiveness, little postoperative wound pain, and small scars. These advantages suggest that this technique may be indicated for benign mediastinal tumors, particularly cysts. 相似文献
78.
This study found a competent transmission of hantavirus between cagemates using congenitally T cell-deficient Rowett nude rats (rnu/rnu). Intraperitoneally infected immunologically normal rats (rnu/+) did not transmit the hantavirus to their normal cagemates (rnu/+) but did to Rowett nude rats (rnu/rnu). Thus, nude rats were shown to be highly susceptible to the hantavirus infection. Also, infected nude rats (rnu/rnu) discharged the infectious viruses, to cause a prevalence of infection among normal cagemates (rnu/+). The infection system demonstrated here using Rowett rats (rnu/rnu) may provide a useful model to study the mechanism of the hantavirus infection. 相似文献
79.
Y Takahama K Ohishi Y Tokoro T Sugawara Y Yoshimura M Okabe T Kinoshita J Takeda 《Canadian Metallurgical Quarterly》1998,28(7):2159-2166
T lymphocytes express various glycosylphosphatidylinositol (GPI)-anchored surface proteins, such as Thy-1 and Ly-6A. However, functional contribution of GPI-anchored proteins in T cell activation is as yet poorly understood. Here we report the generation of mutant mice deficient in the expression of GPI-anchored molecules exclusively in their T cells. We established mice carrying three identically oriented lox-P sites within the Pig-a gene, which encodes a component essential for the initial step of GPI anchor biosynthesis. These mice were crossed with mice carrying the Cre recombinase gene driven by the T cell-specific p56lck proximal promoter. Offspring carrying both the lox-P-containing Pig-a gene and the Cre transgene exhibited almost complete loss of the surface expression of GPI-anchored molecules on peripheral T cells. Interestingly, those T cells deficient in GPI-anchored molecules were capable of responding to T cell receptor stimulation in vitro and in vivo. These results indicate that T cells lacking the expression of GPI-anchored molecules are functionally competent in exerting TCR-mediated immune responses. 相似文献
80.
Watanabe S. Futami F. Okabe R. Ludwig R. Schmidt-Langhorst C. Huettl B. Schubert C. Weber H. 《IEEE journal of selected topics in quantum electronics》2008,14(3):674-680
An optical parametric amplified (OPA) fiber switch is described in this paper. This device switches input signals without shifting the wavelength by changing the polarization state of the signal using optical parametric amplification. The OPA fiber switch features ultra-broadband, highly efficient switching with a high contrast ratio. We experimentally test the prototype of the OPA fiber switch, which uses a highly nonlinear fiber. Optical demultiplexing of 160 Gb/s differential phase-shift keying (DPSK) signals is demonstrated in the whole C-band and shows that it provides almost penalty-free optical detection. The application of amplitude noise suppression with the OPA fiber switch by using parametric gain saturation is then proposed and demonstrated for a 160 Gb/s DPSK signal. When it is set to an amplitude-limiting condition, the OPA fiber switch successfully increases the optical signal-to-noise ratio by 4 dB and effectively suppresses the phase deterioration in 160 Gb/s DPSK transmission by increasing the system margin by more than 5 dB. 相似文献