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排序方式: 共有1572条查询结果,搜索用时 31 毫秒
111.
DD Roman SH Kubo S Ormaza GS Francis AJ Bank SJ Shumway 《Canadian Metallurgical Quarterly》1997,19(5):692-697
Seventeen patients with severe cardiomyopathy underwent neuropsychological evaluation prior to and at least 1 year after successful heart transplantation. Study candidates were screened, and individuals with a history of stroke, cardiac arrest, or medical and neurological conditions which might affect brain function were excluded. Pre-transplant testing revealed normal intelligence and normal attentional, language, and executive abilities but impaired recent memory. Following heart transplant, memory functioning improved significantly, reaching normal levels. Other cognitive abilities remained unchanged. Results suggest that cardiomyopathy is associated with mesial temporal dysfunction, possibly attributable to inadequate or reduced cerebral blood flow and related hypometabolism. This cerebral dysfunction is potentially reversible following successful transplantation, which restores cardiac output and cerebrovascular perfusion. 相似文献
112.
Shingo Date Hiroshi Ishikawa Tomomi Otani Yukio Takahashi Takanori Nakazawa 《Nuclear Engineering and Design》2008,238(2):353-367
Low-carbon 316 stainless steel with medium-nitrogen (316FR) is considered as the principal structural material for next generation fast breeder reactor (FBR) plants in Japan. The material strength standard and the creep-fatigue life evaluation method for 316FR have been developed. However, they are based on the results of material tests in air, while actual structural material will be used mainly in liquid sodium environment in the plants. In order to clarify the environmental effect, cyclic bending tests were carried out with and without hold time in sodium. Tested materials were 316FR and conventional 304 and 316 stainless steels. Weld metal of 316FR was also tested. As a result, it was found that fatigue and creep-fatigue lives of 316FR in sodium were larger than those in air and no explicit consideration of the environmental effect is necessary in design. It was also found that the life evaluation method based on the ductility exhaustion concept is applicable to creep-fatigue life assessment in sodium. 相似文献
113.
Kawahira H. Kubo Y. Yokoyama T. Ogata J. 《Industry Applications, IEEE Transactions on》1990,26(2):359-365
The effect of an electric field on boiling refrigerant R-11 was investigated experimentally. The test section consisted of a flat plate and a single tube with several rows of electrode wire. The influence of refrigerant oil, the surface roughness of the test tube, and polarity of an applied voltage on the heat transfer performance were studied. The following results were obtained: as the applied voltage increased, the number of boiling bubbles decreased but the heat transfer coefficient increased; no deterioration of heat by the oil contamination occurred; and the polarity of the applied voltage affected the boiling heat transfer 相似文献
114.
K Higo Y Kubo Y Iwatani T Ono M Maeda H Hiai T Masuda K Kuribayashi F Zhang TY Lamin A Adachi A Ishimoto 《Canadian Metallurgical Quarterly》1997,71(1):750-754
Fv-4 is a mouse gene that dominantly confers resistance to infection with Friend murine leukemia virus (F-MuLV) (S. Suzuki, Jpn. J. Exp. Med. 45:473-478, 1975). Despite complete resistance to ecotropic MuLV infection in mice carrying the Fv-4 gene, it is known that cells carrying the resistance gene in tissue culture do not always show resistance as extensive as that in vivo (H. Yoshikura and T. Odaka, JNCI 61:461-463, 1978). To investigate the immunological effect on resistance in vivo, we introduced the Fv-4 gene into BALB/c nude mice (Fv-4-/- nude[nu/nu]) by mating them with Fv-4 congenic BALB/c mice (Fv-4r/r nude+/+) and examined the susceptibility of the F2 progeny to F-MuLV. All BALB/c nude mice without the Fv-4 gene (Fv-4-/- nude[nu/nu]) were permissive to F-MuLV and developed erythroleukemia within 2 weeks after virus inoculation. The BALB/c nude mice with the Fv-4 gene (Fv-4r/r nude[nu/nu]) did not develop leukemia, and no or little virus was detected in the spleen 7 weeks after virus inoculation. The resistance to F-MuLV was dominant in (Fv-4 congenic BALB/c x BALB/c nude) F1 mice with the Fv-4r/- nude(nu/+) genotype as strictly as in (Fv-4 congenic BALB/c x BALB/c) F1 mice with the Fv-4r/- nude+/+ genotype. However, almost all BALB/c nude mice with the Fv-4r/- nude(nu/nu) genotype developed the disease within 7 weeks, and the virus was detected in all of their spleens even in the mice without leukemia. These results show that the resistance caused by the Fv-4 gene is recessive in nude mice and dominant in BALB/c mice. Some immunological effects, perhaps cell-mediated immunity, may play important roles in the resistance to F-MuLV infection in vivo in addition to the dosage effect of the Fv-4 product. 相似文献
115.
J Alexander C Oseroff J Sidney P Wentworth E Keogh G Hermanson FV Chisari RT Kubo HM Grey A Sette 《Canadian Metallurgical Quarterly》1997,159(10):4753-4761
Transgenic mice expressing chimeric human (alpha1 and alpha2 HLA-A11 domains) and murine (alpha3, transmembrane, and cytoplasmic H-2Kb domains) class I molecules were derived. These mice were used as a model system to study the immunogenicity of human CTL epitopes and also to examine the aspects of Ag processing differences of mice vs man. Immunization of these mice with seven known HLA-A11-restricted CTL epitopes emulsified in IFA resulted in vigorous specific CTL responses. A larger panel of 45 A11-binding peptides was used to examine the relationship between immunogenicity in the HLA-A11/Kb transgenic mice and HLA-A11 binding capacity. Twenty-one of 28 (75%) peptides with high binding affinities (50% inhibitory concentration (IC50), 2-50 nM) and 7 of 13 (54%) intermediate binding peptides (IC50, 50-500 nM range) were immunogenic. In parallel, 19 of these peptides were used for in vitro primary immunizations of PBMC derived from HLA-A11 healthy human donors. It was found that 8 of 8 peptides that were able to elicit CTL in primary human in vitro cultures were also immunogenic in HLA-A11/Kb mice. Finally, HLA-A11/Kb transgenic mice were found to generate an A11/Kb restricted CTL response following immunization with influenza virus A/PR/8/34, suggesting that, at least to some extent, A11 epitopes are generated by transgenic mice as a result of natural in vivo processing and presentation. 相似文献
116.
The pharmacokinetics of water-in-oil-in-water-type multiple emulsion of a new tacrolimus formulation
Takeji Uno Takaji Yamaguchi Xiao Kang Li Yoshinari Suzuki Hisakuni Hashimoto Yukio Harada Taizou Kimura Teruhisa Kazui 《Lipids》1997,32(5):543-548
We developed a water-in-oil-in-water (W/O/W)-type multiple emulsion of a new tacrolimus formulation. A potential approach
to avoid the complications of systemic immunosuppression and simultaneously enhance immunosuppressive efficacy is to deliver
immunosuppressive agents locally to the site of the target organs. The W/O/W emulsion is dispersed oil drops containing smaller
water droplets that allow the delivery of drugs preferentially to the reticuloendothelial system (RES). Since the liver and
the spleen are primary components of the RES, and the brain and the kidney have a poor RES, we hypothesized that a W/O/W emulsion
of tacrolimus would prossess the pharmacokinetic benefits of local immunosuppression. We evaluated this hypothesis in a rat
model. The tacrolimus levels of whole blood, the liver, spleen, brain, and kidney in rats given intravenous emulsions of tacrolimus
(W/O/W group) were compared with a group administered tacrolimus alone (T group). There were no significant differences between
the pharmacokinetic parameters of W/O/W group and T group based on whole blood data. However, the W/O/W group had significantly
decreased tacrolimus levels in the brain and kidney, and significantly increased levels in the liver and spleen compared with
the T group. These data suggest that the W/O/W emulsion is applicable as an intravenous drug carrier for local immunosuppression. 相似文献
117.
118.
This short communication describes a simple inexpensive instrument employing optical coupling which eliminates electrical shock hazards to hospital patients during signal acquisition. 相似文献
119.
Surface pressure and wind load characteristics on prisms immersed in a simulated transient gust front flow field 总被引:1,自引:0,他引:1
Kyle Butler Shuyang Cao Ahsan Kareem Yukio Tamura Shigehira Ozono 《Journal of Wind Engineering & Industrial Aerodynamics》2010,98(6-7):299-316
Thunderstorm generated gust fronts are responsible for various degrees of structural damage in many areas of the world. However, the resulting impact of gust front winds is not fully understood to such a level that their flow kinematics, dynamics and impact on structures can be quantified with some certainty. Gust front winds are transient in nature and have a flow profile which differs significantly from a typical boundary layer flow field. This study focuses on investigating the effects of this flow profile and its transient nature on the aerodynamics of bluff, prismatic bodies. A gust front type flow field is generated using a multiple fan wind tunnel and the resulting surface pressures are captured on a suite of prismatic models, which vary in size in relationship to the oncoming wind profile. The temporal variations in surface pressures are analyzed using traditional time, frequency and time-frequency domain schemes. Results indicate the changing nature of the surface pressure field in time, highlighting both qualitative and quantitative differences between local and area-averaged pressures under a host of flow profiles. 相似文献
120.
Kuge S. Kato T. Furutani K. Kikuda S. Mitsui K. Hamamoto T. Setogawa J. Hamade K. Komiya Y. Kawasaki S. Kono T. Amano T. Kubo T. Haraguchi M. Nakaoka Y. Akiyama M. Konishi Y. Ozaki H. Yoshihara T. 《Solid-State Circuits, IEEE Journal of》2000,35(11):1680-1689
A 200-MHz double-data-rate synchronous-DRAM (DDR-SDRAM) was developed. The chip contains a delay-locked loop (DLL) which performs over a wide range of operating conditions. Post-mold-tuning allows precise replica programming. A 200-MHz intra-chip data bus is suitable for DDR operation 相似文献