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991.
In an attempt to study codon usage effects of DNA vaccines on the induction of MHC class I-restricted T cell responses against an intracellular bacterium, Listeria monocytogenes, we designed two plasmid DNA vaccines encoding an H-2Kd-restricted epitope of listeriolysin O (LLO) of L. monocytogenes, LLO 91-99. One DNA vaccine, p91wt, carries the wild-type DNA sequence encoding LLO 91-99, and the other one, p91mam, possesses the altered DNA sequence in which the codon usage was optimized for murine system. Our read-through analyses with LLO 91-99/luciferase fusion genes confirmed that the optimized 91mam DNA sequence showed extremely higher translation efficiency than the wild-type sequence in murine cells. Consistent with this, i.m. injections of p91mam, but not of p91wt, into BALB/c mice were capable of inducing specific CTL- and IFN-gamma-producing CD8+ T cells able to confer partial protection against listerial challenge. Taken together, these observations suggest that optimization of codon should be taken into consideration in the construction of DNA vaccines against nonviral pathogens. 相似文献
992.
Prevention of onset in an insulin-dependent diabetes mellitus model, NOD mice, by oral feeding of Lactobacillus casei 总被引:1,自引:0,他引:1
T Matsuzaki Y Nagata S Kado K Uchida I Kato S Hashimoto T Yokokura 《Canadian Metallurgical Quarterly》1997,105(8):643-649
Allogeneic bone marrow transplantation is the only currently available curative treatment for myelodysplastic syndromes (MDSs) but can be used only in the minority of patients (10%) who are younger than 55 years or so and for whom an HLA-identical donor is available. Each year in Europe, about 100 patients with MDSs receive an autologous bone marrow transplant. This procedure is usually indicated as first-line treatment, except in patients without excess of blasts or complex cytogenetic abnormalities. In forms with excess of blasts, chemotherapy prior to bone marrow transplantation deserves discussion. Autologous bone marrow transplants or the more recent technique involving transplantation of autologous peripheral stem cells can be considered in patients who have achieved a complete remission under aggressive chemotherapy. This method has been followed by higher recurrence rates in patients with MDSs than in those with de novo acute myeloblastic leukemia, and randomized studies are under way to compare it with aggressive maintenance chemotherapy. 相似文献
993.
994.
Normal spectral emissivities for solid (ɛλ,solid) and liquid (ɛλ,liquid) copper at the melting point have been determined, and the discontinuity in ɛλ,liquid and ɛλ,solid at the melting point has been discussed. The spectral emissivity was determined by comparing the spectral radiation intensity
of the sample to that of the fixed-point blackbody over the wavelength range 550 to 750 nm. The samples and fixed-point blackbody
were heated in the continuous casting type cold crucible. Values of ɛλ,liquid and ɛλ,solid at 650 nm were 0.167 and 0.108, respectively. The emissivity ratio of ɛλ,liquid/ɛλ,solid increased from approximately 1.2 to 1.8 as the wavelength increased in the range 550 to 750 nm. The discontinuity in ɛλ,liquid and ɛλ,solid at the melting point has been qualitatively explained by the optical absorption mechanism due to the intraband transition. 相似文献
995.
M Ariyoshi T Tamaki H Akashi K Nagata H Ishida K Hiraoka K Sonoda H Satoh H Soh S Satoh T Imamura H Imayama T Shimokobe A Inoue 《Canadian Metallurgical Quarterly》1998,45(3):287-290
PURPOSE: To provide methods for stereoscopic visual demonstration from 3D reconstructed MR angiographic images. METHODS: Stereoscopic viewing can be obtained with pairs of images that are displayed at angles of 15 degrees. Optical devices as stereoscopic binoculars or minor stereoscopes facilitate stereoscopic viewing. The possibility of stereoscopic projections for a larger auditorium is mentioned. RESULTS: Using three clinical examples the advantages of stereoscopic display of MR angiograms are demonstrated. CONCLUSIONS: MR angiography allows stereoscopic viewing with simple methods, like CT- and conventional rotation angiography. This principle, which has been known for 100 years, may thus acquire a new significance. 相似文献
996.
997.
Nojima H. Shintaku H. Nagata M. Kataoka S. 《Electron Devices, IEEE Transactions on》1992,39(3):576-580
The fundamental characteristics of a magnetic sensor fabricated from a Y1Ba2Cu3O7-x ceramic superconducting film are investigated. The operation principle of the sensor is based on the magnetoresistive properties of the material. The Y1Ba2Cu3O7-x ceramic film was prepared by the spray pyrolysis method. An element of the magnetic sensor consists of the film patterned to a meander shape. the sensitivity is discussed in connection with the noise measurement of the element. A magnetic field resolution of 2×10-6 G/(Hz) 1/2 at 100 Hz was obtained in the 0.1-100 G range. The sensitivity is much higher than that of a conventional semiconductor magnetic sensor. With an AC modulation provided by a magnetic field, phase detection of the magnetic field can be performed using a lock-in amplifier. An improvement in the low-frequency (<1 Hz) magnetic field resolution of about one order of magnitude was obtained using this method 相似文献
998.
999.
The plasma etching durability of O2 and CCl4 was investigated for copolymer and polymer blend of poly(methyl methacrylate) (PMMA) and poly(α-methylstyrene) (PMSt) as a function of MSt content. Further, the effects of crosslinking on plasma etching were studied by incorporating N-methylolated methacrylamide into the copolymer as a crosslinkable site during prebaking. The plasma-etching resistance of PMMA was largely improved by incorporating or adding only a small amount of MSt. Especially in the case of the CCl4 plasma etching, the copolymer and the polymer blend with 10 mol% of MSt showed etching resistance as great as that of PMSt homopolymer. Stabilization of the polymers against the plasma etching can be explained by the sponge effect, the energy migration followed by the quenching by the phenyl ring. The polymer blend offered similar etching resistance as the copolymer, indicating an effective occurrence of the energy migration between the polymer chains. Etching resistance was also improved by crosslinking, also due to the enhancement of the sponge effect. 相似文献
1000.