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排序方式: 共有1727条查询结果,搜索用时 953 毫秒
1.
Although the precise pathoetiology of Beh?et's disease (BD) remains obscure, patients with BD have a high incidence of chronic infectious foci, indicating an enhanced susceptibility to chronic tonsillitis, and dental caries. Sometimes, clinical symptoms appear after treatment of these foci in BD patients. It is believed that BD might be related to an allergic reaction to a bacterial infection in view of the many clinical symptoms, especially the presence of aphthous and genital ulcerations. An attempt to obtain cutaneous responses to bacterial antigens has been carried out using various vaccines developed from bacteria isolated from the ulcerative lesions and oral cavities of BD patients. BD patients often show intense hypersensitivity to various strains of streptococci, not only by their cutaneous reactions but also by in vitro testing. In this report, we describe our previous studies on the correlation between streptococcal antigens and the pathogenesis of BD and also discuss the recent reports of other authors. The intense hypersensitivity to streptococcal antigens acquired after streptococcal infection is thought to play an important role in the appearance of symptoms in BD patients since the production of pro-inflammatory cytokines by peripheral blood mononuclear cells (PBMC) was enhanced when stimulated with streptococcal antigen in a culture system. Minocycline, an antibiotic to which certain strains of streptococci are sensitive, reduced the frequency of clinical symptoms in BD patients as well as the production of pro-inflammatory cytokines by BD-PBMC stimulated with streptococcal antigen. 相似文献
2.
Shijie Zhu Yutaka Kagawa Jian-Wu Cao Mineo Mizuno 《Metallurgical and Materials Transactions A》2004,35(9):2853-2859
Time-dependent deformation in an enhanced SiC/SiC composite has been studied under constant load at high temperatures of 1200
°C, 1300 °C, and 1400 °C. Creep damage evolution was evaluated by a Young’s-modulus change of partial unloading and microscopic
observation. The addition of the glassy phase in the matrix is very effective for protecting the composite from oxidation.
The transient creep is dominant in creep life at all the temperatures. An empirical equation is proposed to describe creep
behavior of the composite. It is found that creep activation energy increases with creep time at stresses lower than matrix
cracking stress, but the activation energy remains constant at stresses higher than the matrix cracking stress. The creep
strain rate of the composite is considered to be controlled by creep of fibers based on examining the time, strain, stress,
and temperature dependencies of creep strain rates. 相似文献
3.
Hirokazu Ikeda Chikara Fukunaga Yutaka Saitoh Masahiro Inoue Junko Yamanaka 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,380(3):618-622
The radiation tolerance for prototype front-end chips designed for a silicon micro-strip detector was examined with a 60Co irradiation source to establish an allowable range of the radiation dose. The irradiated front-end chips were SMA2SH-64A, a 64-channel preamplifier array; SMA2SH-1, a single-channel preamplifier circuit with a comparator; and Control-C, a digital-control chip for the preamplifiers. 相似文献
4.
Yutaka Asako Hisayoshi KamikogaHisashi Nishimura Yoshiyuki Yamaguchi 《International Journal of Heat and Mass Transfer》2002,45(11):2243-2253
Compression is one solution to improve the strength of softwoods. The effective thermal conductivities of compressed Japanese cedars (cryptomeria japonica), which were compressed in the radial direction of the wood, were measured. Both the effective thermal conductivities in the tangential and fiber directions increase proportionally to the density increment due to the compression. However, the thermal conductivity in the radial direction (compression direction) increases slightly with the density increment. Numerical computations were conducted to explain the characteristics of thermal conductivity in the radial direction by using a microscopic heat conduction model for the compressed wood. The numerical results were compared with the measured values. And the physical mechanism of the heat conduction in the compressed woods is discussed. 相似文献
5.
A single loop electrochemical potentiokinetic reactivation test method has been developed for alloy 600 that produces good passivation on all the surfaces, good etching during the reactivation scan and no appreciable pitting. It is able to quantify and discriminate between samples with a wide range of degree of sensitization. The Pa value correlates well with the minimum level of chromium in the depletion regions at the grain boundaries. It has been shown that the width of the attacked regions is much larger than the width of chromium depletion regions and it does not show any direct correlation with either depth or width or with a volume parameter of chromium depletion regions. It has been shown that the chromium carbides are not attacked during the test and that the intragranular regions attacked during the test are the sites of chromium carbides in the grain matrix. A modified Pa parameter is shown to be sensitive down to 7.5 wt% chromium in the depletion regions and indicates that the intragranular carbides have shallower depletion profiles than those at grain boundaries. Comparison of the results of the single loop and the double loop tests showed a good correlation. 相似文献
6.
The effect of Zr on reduction of hardness and microstructure in an FS weld of equal channel angular-pressed Al alloy was investigated. Zr addition to Al suppressed dynamic recovery in the thermomechanically affected zone and enabled retention of the high hardness of the ECA-pressed material throughout the weld. 相似文献
7.
T Oyama T Osaki T Mitsudomi R Ogawa R Nakanishi K Sugio K Yasumoto 《Canadian Metallurgical Quarterly》1998,1(5):823-826
We examined p53 protein expression, p53 gene mutation, proliferating cell nuclear antigen (PCNA), and argyrophilic nuclear organizer regions (AgNOR), in 30 patients with surgically-treated thymic tumors (26 thymoma and 4 thymic carcinoma cases). p53 expression ratio with DO-1 was divided as p53 negative (0% positivity), low expressor (<10% positivity), high expressor (>10% positivity). The incidence of p53 low and high expressor in thymoma were 19% (5/26) and 8% (2/26), respectively. p53 immunopositivity in thymoma was significantly correlated with PCNA labeling index (LI). p53 expression ratio in invasive thymoma (33%) tended to be higher than that in non-invasive thymoma (18%). p53 expression was detected in one of the thymic carcinoma. There were no p53 gene mutations in 15 invasive thymoma, although one of four (25%) thymic carcinomas showed two point mutations. p53 gene alterations seem to be associated with malignant activity of tumor cells, and therefore detection of p53 gene mutations is useful as a diagnostic factor. 相似文献
8.
In recent years the requirement for the reduction of energy consumption has been increasing to solve the problems of global warming and the shortage of petroleum resources. For example, in the power generation field, as thermal power generation occupied 60% of the power generation demand, considerable improvement of the thermal efficiency is required. This paper describes the pressure drop characteristics of finned tube banks used for heat exchangers in thermal power generation that were clarified by testing serrated finned tube banks with different fin heights for improved heat transfer and conventional spiral finned tube banks with different fin heights, and an equation to predict pressure drop which is necessary for the heat exchanger design is proposed. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(3): 179–193, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20112 相似文献
9.
When West meets East: Contributions of Eastern traditions to the future of psychotherapy. 总被引:1,自引:0,他引:1
Bankart C. Peter; Koshikawa Fusako; Nedate Kaneo; Haruki Yutaka 《Canadian Metallurgical Quarterly》1992,29(1):141
Discusses 2 interrelated traditions as they are reflected in contemporary and traditional approaches to psychotherapy in Japan. One uses various meditational and self-focusing instructional sets whose common goal is to facilitate the slowing down, deepening, and clearer focusing of sensory and interpersonal awareness. The 2nd tradition focuses on physical self-regulation and autonomic self-control through exercises that foster enhanced voluntary control over physical states and processes. Eastern psychology offers a set of practices that help the individual overcome the inherent selfishness of his/her isolated experience. The goals of such work include recognition of gratitude to important people in the client's life, rediscovery of the joy of meaningful work, and the experience of a unifying cosmic consciousness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
A series of Mo–TiC alloys were heated in vacuum at 2473 K for 36 ks. First grain growth behavior was observed using a scanning electron microscope. Then effects of TiC addition on the strengths and ductility at low temperature were discussed from the viewpoints of chemical composition and grain structure.
Materials with TiC additions of not larger than 0.1% demonstrated a single-crystalline grain structure. Both yield and maximum strengths increased by TiC addition and consequently ductility was improved. 相似文献