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41.
M Kosaka 《Canadian Metallurgical Quarterly》1998,101(7):916-923
A retrospective study of 85 patients with IgA nephropathy was undertaken to determine the long-term effect of tonsillectomy. Forty-three patients (24 males and 19 females) had received tonsillectomies (Group A) and 42 patients (17 males and 25 females) had not (Group B). These patients had been followed up for more than 5 years after renal biopsy. The average age at the initial renal biopsy was 25.72 years in Group A, and 33.16 years old in Group B. The average period of renal biopsy to tonsillectomy in Group A was 10.47 months. The average follow-up period was 8 years and 9 months in both groups. At the beginning of treatment, the two groups were well matched in terms of creatinine clearance, urinalysis, and blood pressure. Six patients in Group A and eight patients in Group B were treated with steroids. The glomerular injury detected at the renal biopsy was more extensive in Group A than in Group B. Renal function in the two groups was compared. The clinical remission rate in Group A was significantly higher than in group B (P<0.05). The stable renal function rate in Group A was significantly higher than in Group B (P<0.05). The renal survival rate was 97.7% in Group A and 83.3% in Group B, but there was no significant difference between the two groups. Histologically, the rate of remission of the minor lesion in Group A was significantly higher than in Group B (P < 0.05). Our results showed that tonsillectomy for IgA nephropathy was clinically of great value. 相似文献
42.
G. O. Shonaike H. Hamada Z. Maekawa S. Yamaguchi M. Nakamichi W. Kosaka 《Journal of Materials Science》1995,30(2):473-480
The mechanical properties of polyphenylene sulphide (PPS) and liquid crystalline polymer (LCP) blends were investigated over a range of temperatures. The effect of blend composition on the brittle-ductile transition temperature (B-D) was also studied by differential scanning calorimetry and scanning electron microscopy. Blends of various compositions (PPS/LCP; 90/10, 75/25, 50/50 and 25/75) were prepared and injection moulded. The bending test temperature was varied between –40 and 150 °C. The results showed a rapid load drop at the B-D transition region. The B-D transition temperature occurred in unannealed pure PPS, 90/10, 25/75 and 50/50 blends around 75 °C whilst in the annealed sample it was observed around 100 °C. In pure LCP and 25/75, no transition occurred. Partial miscibility of PPS and LCP was confirmed by SEM observations, bending modulus and thermal properties. The use of LCP, as a good reinforcing agent which can improve processability and modulus, is discussed. 相似文献
43.
Kosaka H. Ogura I. Saito H. Sugimoto M. Kurihara K. Numai T. Kasahara K. 《Photonics Technology Letters, IEEE》1993,5(12):1409-1411
Bidirectionally cascadable optical pixels that consist of a single-vertical-cavity surface-emitting laser (VCSEL) thyristor and a double-vertical-cavity phototransistor are proposed. Despite almost identical layer structures, each device characteristic can be independently optimized by introducing a λ/2-spacer layer into the phototransistor section. A lasing threshold of 0.8 mA and a slope efficiency of 0.25 W/A are obtained for the laser thyristor, and a flat-topped photocurrent spectrum over 30 A and a photocurrent gain of 70 A/W are obtained for the phototransistor at the resonant wavelength. This work demonstrates the possibility of monolithic integration using thermal desorption and a regrowth technique and the suitability of these devices for massively parallel optical interconnections 相似文献
44.
Hiroshi Uda Hideo Yonezawa Yoshikazu Ohtsubo Manabu Kosaka Hajimu Sonomura 《Solar Energy Materials & Solar Cells》2003,75(1-2):219-226
Polycrystalline CdS thin films have been deposited on borosilicate glass substrates coated with ITO film by metalorganic chemical vapor deposition using dimethyl cadmium and diethyl sulfide as source materials. The growth of CdS film occurred at substrate temperatures within the range of 280–360°C. The deposition rate increased with increasing VI/II molar ratio at any substrate temperature and showed a maximum value at the VI/II molar ratio of 4. The grain size of as-deposited CdS film prepared at substrate temperatures from 300°C to 360°C was about 0.1 μm. The CdS films consist of hexagonal form with a preferential orientation of the (0 0 2) plane parallel to the substrate. Thin CdS film with high optical transmittance was prepared at 350°C with the VI/II molar ratio of 4. The CdS film deposited by MOCVD may be used as a window layer for CdS/CdTe solar cell. 相似文献
45.
Yablonovitch E. Jiang H.W. Kosaka H. Robinson H.D. Rao D.S. Szkopek T. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2003,91(5):761-780
The transmission of quantum information over long distances will allow new forms of data security, based on quantum cryptography. These new technologies rely for security on the quantum "uncertainty principle" and on the long distance transmission of "quantum entanglement." A new type of telecommunications device called the "quantum repeater" can allow the faithful transmission of quantum information over worldwide distances, in spite of the inevitably severe losses while propagating along optical fibers. In a quantum repeater, information is stored in the quantum state of a semiconductor electron spin, while complementary entangled information is transmitted as a photon down the optical fiber. This long-range entanglement permits the execution of the teleportation algorithm, which accurately transmits a quantum state over long distances. The quantum repeater is an excellent stepping stone to larger quantum information processors, since teleportation requires only three quantum logic gates. This paper reviews the experimental status of semiconductor quantum repeaters, including the spin resonance transistor logic gates, and the experimental detection of single photons in a manner that preserves their spin information. 相似文献
46.
Y Yamamori Y Saito M Kaneko Y Kirihara S Sakura Y Kosaka 《Canadian Metallurgical Quarterly》1996,43(11):1175-1179
PURPOSE: The present study was designed to examine the antinociceptive effects of orally administered ONO-9902, an enkephalinase inhibitor, on both somatic and visceral pain after visceral stress conditions. METHODS: Twenty six male rats were examined. Tail-flick (TF) and colorectal distension (CD) tests were used to determine somatic and visceral antinociceptive effects, respectively. Measurements were performed in rats under immediate post-stress conditions (group ST; n = 14) and in rats nor under stress conditions (group NST; n = 12). In the stressed group, the same device, CD, for visceral antinociceptive effects was used for visceral stress and was applied with an intracolonic pressure of 60 mmHg for 20 min after drug administration. The TF latency and CD threshold were measured before and at 30, 40, 50, 60 and 90 min after administration of ONO-9902 300 mg.kg-1 or distilled water. RESULTS: Orally administered ONO-9902 did not produce any changes in the % maximum possible effect (%MPE) in either TF or CD tests in the unstressed group. In the stressed group, %MPE in the CD test increased 18% and 31% at 30 and 40 min, respectively, after oral administration of ONO-9902 compared with the control group (P < 0.05). However, %MPE to TF test did not alter even after the CD-induced stress condition. CONCLUSION: These results suggest that ONO-9902 may have analgesic effects on visceral pain but not on somatic pain under immediate post-stress conditions. 相似文献
47.
Number, length, and diameters of dendritic spines of the granule cell in the dorsal leaf of the rat dentate gyrus were measured by using high-voltage electron microscope stereo images of 5-m?m-thick Golgi preparations with the aid of a three-dimensional image analyzer system. Spine densities of 2.02 ± 0.28, 2.28 ± 0.33, and 3.36± 0.35 per 1 μm at distal, middle, and proximal portions of the dendrite were obtained. These values were about 1.6-fold of the previous light microscopical report. Mean three-dimensional spine length were 1.244 ± 0.506 μm, 1.262 ± 0.563 μm, and 1.254 ± 0.584 μm at distal, middle, and proximal portions, respectively, which were about 1.4 times longer than those measured in two dimensions. By using measured morphometrical parameters of spines such as lengths, diameters, and population densities, total spine surface areas of 2.401 μm2, 2.806 μm2, and 4.180 μm2 per 1 μm of the dendrite at distal, middle, and proximal portions, respectively, were obtained. The total surface area of dendrite was about doubled by the addition of the spines at each dendritic portion. The advantageous features and the problems of the present method are discussed. 相似文献
48.
The shear viscosity of blend solutions of hydroxypropyl cellulose (HPC) and ethyl cellulose (EC) in m-cresol (both HPC/m-cresol and EC/m-cresol systems form lyotropic liquid crystals) was determined by cone-plate-type and capillary-type viscometers. The textures for the same systems at rest and undergoing shear were also observed with a polarized microscope. At shear rate of 1 s?1, viscosity exhibited a maximum and a minimum with respect to temperature, and this suggested that the phase of the matrix dominated the viscometric behavior of the ternary systems; the blend composition dependence of the viscosity was not additive, and this suggested that HPC and EC were immiscible. At relatively high shear stress, the blend composition dependence of the viscosity greatly depended on the total polymer concentration of the solutions and was quite different from that at low shear rate; the texture of the anisotropic solutions was also different from that at low shear rate. Our findings suggested that the dependence of viscosity on shear and concentration for pure HPC solution was different from that for pure EC solution. 相似文献
49.
This paper deals with the dynamic characteristics of a helium-heated heat-exchanger type steam reformer with catalyst tubes of industrial size. A nonlinear dynamic model was developed based on algebraic and ordinary differential equations which describe material, component and energy balances. This model was numerically linearized around an operating point. In addition, an auto-regressive model was obtained from experimental input-output data in which the inputs were perturbed simultaneously using pseudo-random binary sequences. Experimental data obtained by step and PRBS testing were used for comparison with the simulated responses. The comparison showed that the simulated responses agreed reasonably well with the experimental data. 相似文献
50.
Composites of linear low‐density poly(ethylene‐co‐butene) (PE) or maleated linear low‐density poly (ethylene‐co‐butene) (M‐PE) and cellulose (CEL), cellulose acetate (CA), cellulose acetate propionate (CAP), or cellulose acetate butyrate (CAB) were prepared in an internal laboratory mixer with 20 wt % polysaccharide. The structure and properties of the composites were studied with tensile testing, dynamic mechanical thermal analysis, differential scanning calorimetry, extraction with a selective solvent, Raman spectroscopy, and X‐ray diffraction. Composites prepared with M‐PE presented yield stress and elongation values higher than those of composites prepared with PE, showing the compatibilizer effect of maleic anhydride. Dynamic mechanical thermal analysis performed for M‐PE–CEL, M‐PE–CA, M‐PE–CAP, and M‐PE–CAB composites showed one glass‐transition temperature (Tg) close to that observed for pure M‐PE, and for M‐PE–CAP, another Tg lower than that measured for the polysaccharide was observed, indicating partial mutual solubility. These findings were confirmed by the extraction of one phase with a selective solvent, gravimetry, and Raman spectroscopy. X‐ray diffraction showed that the addition of CEL, CA, CAP, or CAB had no influence on the lattice constants of PE or M‐PE, but the introduction of the reinforcing material increased the amorphous region. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103:402–411, 2007 相似文献