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排序方式: 共有879条查询结果,搜索用时 15 毫秒
91.
Y Sakurai K Teruya N Shimada K Wakabayashi T Umeda S Honjo I Todoroki H Tanaka T Muto M Sakurai K Nakamura 《Canadian Metallurgical Quarterly》1997,20(6):978-982
OBJECTIVE: To investigate the independent effect of weight change in young adulthood on the risk of prevalent NIDDM among middle-aged Japanese men. RESEARCH DESIGN AND METHODS: A case-control study was carried out in 895 male employees aged > or = 30 years of a railway company located in the vicinity of Tokyo. Adjusted odds ratios (ORs) were calculated for prevalent diabetes in each category of weight change (obtained from subjects' medical records) in young adulthood and adulthood. Adjustment for current age, initial BMI, and weight change in each age stratum was performed by the Mantel-Haenszel method or multiple logistic regression analysis. RESULTS: Weight change between 20 years of age and the age at maximum weight was not associated with the risk of NIDDM. Weight gain between 20 and 25 years of age was significantly and positively associated with the risk of NIDDM (OR 3.87 for gains > or = 10.0 kg, 2.53 for gains of 5.0-9.9%, and 3.73 for gains > or = 10.0%). On the other hand, moderate weight gain after 30 years of age was significantly inversely associated with NIDDM (OR 0.44 for gains of 5.0-9.9 kg, 0.15 for gains of 10.0-19.9%, and 0.38 for gains of 20.0-29.9%). CONCLUSIONS: Extreme weight gain between 20 and 25 years of age is a significant predictor of NIDDM, independent of current age, BMI at 20 years of age, and weight change within other age strata. 相似文献
92.
The respiratory burst assay was conducted using the nitroblue tetrazolium reduction method and horseradish peroxidase method to investigate the events when ayu head kidney macrophages phagocytize fresh and formalin-killed Glugea plecoglossi spores. The production of O2 against G. plecoglossi spores was negligible compared to zymosan (P < 0.01). Zymosan-induced O2 production was markedly inhibited by adding G. plecoglossi spores simultaneously (P < 0.01). This phenomenon was dose dependent, and killed spores were less inhibitory than fresh spores. The production of H2O2 was drastically increased when G. plecoglossi spores were added (P < 0.01), and most spores were phagocytized. From these results, it is suggested that G. plecoglossi spores modulate the host's phagocytic response to establish infection. 相似文献
93.
S Endo K Inada T Kasai S Koike Y Kamei Y Yamada G Wakabayashi M Yoshida Y Yanagiya 《Canadian Metallurgical Quarterly》1997,95(1):109-112
The mixture of 5'-guanylylimidodiphosphate (Gpp(NH)p)/EDTA/NaCl has been used to delineate low-affinity conditions for agonists binding to G-protein-linked receptors. The effects of this mixture on [3H]RX821002 (2-methoxyidazoxan) binding to alpha2-adrenoceptors were evaluated in different tissues. The density of alpha2-adrenoceptors in the presence of the mixture was 11, 78 and 60% higher in human cortex (predominant alpha2A), human caudate (alpha2A + alpha2C) and rat kidney (alpha2A + alpha2B), respectively, than in its absence. In rat kidney, masking of alpha2B-adrenoceptors by ARC239 (2-[2-[4-(o-methoxyphenyl)-piperazin-1-yl]-ethyl]-4,4-dimethyl-1,3 -(2H,4H)-isoquinolindione) (50 nM) or masking of alpha2A-adrenoceptors by BRL44408 (2-[2H-(1-methyl-1,3-dihydroisoindole)methyl]-4,5-dihydroimidaz ole) (100 nM) demonstrated that the increase was in the alpha2B-adrenoceptor but not in the alpha2A-adrenoceptor subtype. 相似文献
94.
95.
Atsuko Takita Katsuhiko Sasaki Ken-ichi Ohguchi 《Journal of Electronic Materials》2014,43(7):2530-2539
For the design of high-density electronic packages, finite element method (FEM) analyses to evaluate strength reliabilities of solder joints should be conducted by employing the material parameters which can precisely reflect the creep properties of solder joints in actual electronic equipment. To obtain accurate results of the structural analyses of the solder joints, a method to evaluate the steady-state creep deformation in situ must be developed. The indentation creep test is an effective method to evaluate the creep properties of the solder joints in situ; however, the creep properties obtained by this method do not give the same results as those obtained by tensile creep tests using bulk specimens. In this paper, the indentation creep test at 1 N loading for 9,000 s duration was experimentally conducted to confirm that the steady-state creep deformation obtained by the indentation creep test did not coincide with that by the tensile creep tests using bulk specimens. To identify the reason, the indentation creep simulation was conducted by FEM analysis. As a result, it was found that the reference area used to obtain the creep strain from the indentation creep test should be modified. A method to obtain the new reference area is proposed from comparisons of experiments with simulations. Finally, this paper shows that the creep properties obtained by the indentation creep test using the new reference area coincided with those obtained by tensile creep tests using bulk specimens. 相似文献
96.
Yoshifumi Ikoma Kazunori Hayano Kaveh Edalati Katsuhiko Saito Qixin Guo Zenji Horita Toshihiro Aoki David J. Smith 《Journal of Materials Science》2014,49(19):6565-6569
This paper describes fabrication of Si nanograins through allotropic phase transformation by concurrent application of high pressure and intense straining using high-pressure torsion (HPT). Single-crystalline Si(100) wafers were processed by HPT under a pressure of 24 GPa at room temperature. X-ray diffraction and Raman analysis revealed that the HPT-processed samples were composed of metastable Si-III and Si-XII phases and amorphous phases in addition to the original diamond-cubic Si-I phase. It was found that nanograins formed because the Si-I diamond phase had transformed to high-pressure phases (Si-II, Si-XI, and Si-V) having metallic nature, and it then became easier to generate a high density of dislocations to form grain boundaries. The high-pressure phases were further transformed to the Si-XII and Si-III phases via the Si-II phase upon unloading and they existed as metastable phases at ambient pressure. Subsequent annealing at 873 K gave rise to reverse transformation to Si-I but with nanograin sizes. Although no appreciable photoluminescence (PL) peak was observed from the HPT-processed sample, a broad PL peak centered around 600 nm was detected from the annealed sample due to quantum confinement in the Si-I nanograins. 相似文献
97.
Chen Zhong Katsuhiko Saito Kazuaki Kawaguchi Hiroshi Setoue 《Packaging Technology and Science》2014,27(7):509-520
To verify the cushion performance of transport packaging, two traditional drop test methods – free fall and controlled shock tests – and a traditional simulation method are often used. However, it is difficult to assure the safety of a test product when the traditional drop test method is applied, and results from the traditional simulation method are not sufficiently accurate to be used to test packaging material. Therefore, we propose a new test method called ‘the hybrid drop test’ by integrating the traditional drop test and simulation methods. The hybrid drop test ensures the safety of the test product and improves test efficiency. The results of the verification test show that this new drop test method can be applied to test the cushion performance of pulp mould transport packaging. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
98.
Qixin Guo Masaki Nada Katsuhiko Saito Mitsuhiro Nishio 《Materials Research Bulletin》2011,46(4):551-554
The effect of gas flow rate on surface morphology and crystal quality of ZnTe layers grown on the (1 0 0) GaAs substrates by atmospheric pressure metalorganic vapor phase epitaxy with dimethylzinc and diethyltelluride as the source materials was investigated. The surface morphology of the ZnTe epilayers is significantly improved with increasing the total gas flow rate. X-ray rocking curve and photoluminescence measurements indicate that the total gas flow rate plays a vital role in the growth characteristics of the ZnTe epilayers, and the ZnTe epilayer with best crystal quality is obtained at the total gas flow rate around 300 standard cubic centimeters per minute (sccm) in this work. 相似文献
99.
Katsuhiko Suzuki 《中国建筑装饰装修》2011,(10):28-31
这是一个三层楼的大专卖店,位于东京著名的表参道。根据Agnes b新的品牌形象,建筑幕墙被设计成黑色,而室内则相反,以白色和灰色为主调。黑色幕墙有的部分是透明的,形成橱窗, 相似文献
100.
Gradually increasing pressure drop, which ultimately leads to a rapid increase, is a problem encountered in moving granular bed filters when gas velocity is elevated during dust collection from the top gas of a blast furnace. The relationship between dust collection and pressure drop was mathematically simulated, and then a half-size test model moving granular bed filter was used to examine the conditions under which the medium can flow. The increase in gas pressure drop proceeds as a circular chain of interrelated events. When gas velocity is increased and the gas pressure gradient exceeds a certain critical value, the medium flow stalls along the gas discharge side of the bed. Dust accumulates in the stalled medium, raising the pressure gradient even further. The growth in pressure drop is thus accelerated, finally resulting in a rapid and undesirable increase that prevents further operation. 相似文献