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排序方式: 共有517条查询结果,搜索用时 46 毫秒
21.
S. Nakao K. Ueno T. Hanaguri K. Kitazawa T. Fujita Y. Nakayama T. Motohashi J. Shimoyama K. Kishio T. Hasegawa 《Journal of Low Temperature Physics》1999,117(3-4):341-345
We have performed scanning tunneling microscopy/spectroscopy (STM/STS) on single crystals of heavily Pb-doped Bi
2
Sr
2
CaCu
2
O
y
(Pb-Bi2212). The obtained STM images clearly demonstrated phase separation into the and phases with lamella-type and new zigzag-like microstructures. From the site-specified tunneling measurements, it was directly confirmed that the phase possesses higher T
c
. This suggests that the phase boundaries act as strong pinning sites especially at higher temperatures. 相似文献
22.
K Kurozumi T Nishida K Nakao M Nakahara M Tsujimoto 《Canadian Metallurgical Quarterly》1998,22(8):853-7; discussion 857-8
Lymph node metastasis is a critical prognostic factor for gastric cancer. In the present investigation we examined clinicopathologic factors influencing the metastatic processes to the lymph mode and their prognostic importance. A randomly selected group of 98 patients with adenocarcinomas of the stomach who underwent gastrectomy plus systematic lymph node dissection at Osaka Police Hospital from 1991 to 1996 were analyzed. Altogether 37 (38%) cancers were positive for CD44 variant 6 (v6) staining, 31 (32%) were intermediately stained, and 30 (30%) were negative. CD44-v6 expression correlated well with lymph node metastasis. Expression of CD44-v6 and lymphatic invasion were independent risk factors for metastatic lymph nodes. Among the patients with CD44-v6-positive and lymphatic invasion-positive cancers, 88% had lymph node metastasis, whereas only 13% of patients negative for both factors had lymph node metastasis. Although CD44-v6 expression and lymphatic invasion have been reported to be risk factors for recurrence and a poor prognosis, in this investigation these factors were found not to be significant for hematogenous and lymphatic recurrences or overall survival rates. Thus expression of CD44-v6 and lymphatic invasion may regulate lymph node metastases from gastric cancer. 相似文献
23.
H Michibata M Mukoyama I Tanaka S Suga M Nakagawa R Ishibashi M Goto K Akaji Y Fujiwara Y Kiso K Nakao 《Canadian Metallurgical Quarterly》1998,53(4):979-985
Neuropsychological profiles were assessed in a large group of nondemented control subjects (n = 261) and individuals with dementia of the Alzheimer type (DAT) (n = 407) by subjecting their psychometric test results to a factor analysis. Nondemented control subjects were functionally homogeneous with only one factor accounting for the results. The results of the factor analysis on the very mild DAT and mild DAT groups, however, yielded a mental control/frontal factor, a memory-verbal/temporal factor, and a visuospatial/parietal factor. Forty-one of the original set of participants came to autopsy an average of 5.1 years after psychometric testing and had neurofibrillary tangles, total senile plaques, and cored senile plaques estimated from frontal, temporal, and parietal regions. The results of correlations indicated that the relative burden of cored senile plaques was systematically related to the three psychometric factors. These results suggest a connection between the specific functions as defined by neuropsychological measures and specific neuropathology occurring in associated areas of cortex. 相似文献
24.
25.
Kadota M Yoneda T Fujimoto K Nakao T Takata E 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2004,51(2):202-210
The authors have succeeded in exciting a new type of leaky surface acoustic wave (LSAW) having only a shear horizontal (SH) component that has a large electromechanical coupling factor, a large reflection coefficient, and excellent temperature stability, by combining interdigital transducers (IDTs) and reflectors made of heavy-metal films such as gold (Au), tantalum (Ta), and tungsten (W) on the ST-cut 90/spl deg/ X propagation (direction perpendicular to the X-axis) quartz substrate. This LSAW does not have a propagation decay. The square of the electromechanical coupling factor is 2.1-2.7 times larger than, the reflection coefficient is 30 times larger than, and the temperature characteristic is the same as those of a Rayleigh wave on an ST-cut X propagation quartz substrate. The authors applied this SH LSAW to resonators and resonator filters. As a result, we succeeded in developing the low loss and very small-sized resonators and resonator filters (1/5-1/4 of conventional device sizes) with IDTs with a small number of finger pairs and very small reflectors, for the first time. 相似文献
26.
Necessary and sufficient conditions for output feedback decoupilng of linear time-invariant multivariable systems into single input-multioutput subsystems are derived in frequency domain. The conditions imply a new constructive method for determining a constant gain output feedback matrix and some of its elements can be freely chosen to reassign the closed-loop poles. 相似文献
27.
STATEMENT OF PROBLEM: The surgical and restorative procedures at the posterior region of the maxilla and the mandible present a complex task in the treatment of partially edentulous patients. PURPOSE: The purpose of this study was to investigate the applicability of short hydroxylapatite-coated dental implants to the posterior mandible of partially edentulous patients. MATERIAL AND METHODS: Eight and 11 mm implants were evaluated as to their cumulative survival rate, clinical status (plaque index, gingival index, probing depth), and marginal bone loss over a 5-year period. RESULTS AND CONCLUSIONS: The verified overall cumulative survival rate was 94% for implants and 91% for prostheses. These results suggest predictable success for the application of short implants to the posterior mandible. 相似文献
28.
T Tagami H Nakamura S Sasaki Y Miyoshi K Nakao 《Canadian Metallurgical Quarterly》1997,154(3):523-533
Hormonal responsiveness in peripheral tissues is variable in patients with resistance to thyroid hormone (RTH). One cause of this may be differential interaction of RTH mutants of thyroid hormone receptor beta (TR beta) with TR auxiliary proteins (TRAPs). We used gel shift mobility assays to examine the interaction of wild-type and mutant TR beta s with retinoid X receptors (RXRs) and endogenous TRAPs. Some mutants showed reduced homodimerization but retained heterodimerization with recombinant RXRs. Wild-type TR beta formed heterodimeric complexes with multiple TRAPs in nuclear extracts of rat tissues, but RTH mutants showed variably altered heterodimerization with each TRAP. With liver nuclear extract, all mutants with impaired homodimerization also showed impaired TR beta-TRAP heterodimerization. Thus heterodimerizations with RXRs and TRAPs are differently affected by RTH mutations. Our results suggest that multiple TRAPs are expressed in tissue-specific patterns. The variability of TR beta heterodimerization with TRAPs may account, in part, for the variable tissue responsiveness in RTH. 相似文献
29.
The infrared chemiluminescence spectra of CO2 formed during steady-state CO+NO reaction over Pd(110) indicated that the temperature of the bending vibrational mode was much higher than that of the antisymmetric one at higher surface temperatures such as 800–850 K. Especially, in the high temperature range, more vibrationally excited CO2 was formed from CO+NO reaction than CO+O2 reaction. On the basis of the result, we propose the model structure of reaction intermediates for CO2 formation in CO+NO reaction, which is different from that in CO+O2 reaction. 相似文献
30.
Electrolytic removal of ammonia from brine wastewater: scale‐up,operation and pilot‐scale evaluation
Catalino G Alfafara Takayuki Kawamori Nakao Nomura Masayuki Kiuchi Masatoshi Matsumura 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(3):291-298
Brine wastewater with a high ammonia content from an iodine processing plant (commonly called kansui in Japan) was treated by electrolysis. The system, which can be considered as an indirect electrolytic treatment process, generates chlorine at the anodes and initiates the formation of mixed oxidants like hypochlorous acid. The oxidants then act as agents for ammonia destruction. Laboratory‐scale experiments showed that high ammonia concentrations (as much as 200 mg dm?3) could be completely removed within a few minutes, and could be considered a good alternative for efficient ammonia removal from saline wastewaters. From laboratory‐scale experiments in the batch and continuous modes, the charge dose was analyzed and used as the operating and scale‐up factor. The value of the charge dose was not severely affected by changes in operating conditions such as electrode spacing and temperature. The charge dose from batch and continuous runs was found to be in the range of 23 C (mg NH4‐N removed)?1 to 29 C (mg NH4‐N removed)?1. Using the charge dose obtained from laboratory‐scale continuous electrolysis experiments as the scale‐up factor, a pilot‐scale reactor was designed, and the operating conditions were calculated. In the pilot‐scale reactor tests at different flow rates, the effluent ammonia concentrations were reasonably close to the calculated values predicted from the charge dose equation. Copyright © 2004 Society of Chemical Industry 相似文献