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991.
Glycogen has been reported to have immune-regulating activity. We examined in this study the immune-regulating activity of wheat starch of various molecular weights, because both starch and glycogen are made from glucose components linked by α-1,4 and α-1,6 glycoside bonds. Wheat starch was treated by sulfuric acid to prepare starch samples with differing molecular weight. The acid-treated starch inhibited cytokine production from murine splenocytes when the splenocytes were incubated with the antigen and a starch sample. The activity depended on the treatment time by sulfuric acid. Mice were then i.p. immunized with some antigens and the starch mixed with two types of adjuvant. The starch also inhibited the in vivo antibody production when administered with an alum adjuvant. In contrast, the starch enhanced the antibody response when administered with complete Fround adjuvant, indicating that the starch regulated immune responses depending on the molecular weight and surrounding circumstances. 相似文献
992.
993.
Hideki Hasegawa Hiroshi Takahashi Toshiyuki Yoshida Takamasa Sakai 《Materials Science and Engineering: B》2001,80(1-3):147-151
A ultrahigh vacuum contactless capacitance–voltage technique is described as a powerful in situ surface characterization of growth and processing steps for III–V device fabrication. The technique was applied to characterization of MBE-grown surfaces and to optimization of the silicon interface control layer-based surface passivation. 相似文献
994.
Measurement of 240Pu/239Pu isotopic ratios in soils from the Marshall Islands using ICP-MS. 总被引:2,自引:0,他引:2
Y Muramatsu T Hamilton S Uchida K Tagami S Yoshida W Robison 《The Science of the total environment》2001,278(1-3):151-159
Nuclear weapons tests conducted by the United States in the Marshall Islands produced significant quantities of regional or tropospheric fallout contamination. Here we report on some preliminary inductively coupled plasma-mass spectrometry (ICP-MS) measurements of plutonium isolated from seven composite soil samples collected from Bikini, Enewetak and Rongelap Atolls in the northern Marshall Islands. These data show that 240Pu/239Pu isotopic signatures in surface soils from the Marshall Island vary significantly and could potentially be used to help quantify the range and extent of fallout deposition (and associated impacts) from specific weapons tests. 137Cs and 60Co were also determined on the same set of soil samples for comparative purposes. 相似文献
995.
Dong-Rong Hwang Masamitsu Tamura Tadao Yoshida Nariaki Tanaka Fumio Hosoya 《Journal of Energetic Materials》2013,31(1-2):85-98
Abstract The AM1 molecular orbital method and reduced pressure differential scanning calorimetry(RP-DSC) were applied to nitro derivatives of benzene and toluene for estimating Δf(1) and Δf(c). The heats of phase change were determined by RP-DSC with moderate accuracy and the combination of the heats and Δf(g) estimated by AM1 gave Δf in condensed phases which are similar to those found in literatures. 相似文献
996.
997.
Kazushi Sumitani Ryota Ohtani Tomohiro Yoshida You Nakagawa Satoshi Mohri Tsuyoshi Yoshitake 《Diamond and Related Materials》2010,19(5-6):618-620
We investigated influences of a repetition frequency of laser pulses on growth of AlN crystalline films by pulsed laser deposition. The structural and morphological properties of the films were studied by X-ray diffraction and scanning electron microscopy. Employment of high frequency laser pulses not only enhanced the growth of AlN crystallites, but also afforded the crystal growth at higher nitrogen pressures. Growth of α-AlN was dramatically enhanced with an increase in the laser pulse frequency, while β-AlN was grown at the high frequency of laser pulses and high nitrogen pressures. 相似文献
998.
999.
A new leak element, which is named as “standard conductance element (SCE)”, has been developed for in situ calibration of ionization gauges (IGs) and quadrupole mass spectrometers (QMSs). The SCE is made of a stainless-steel sintered filter with the pore size of less than 1 μm. Since the gas flow through the SCE satisfies the molecular flow condition even at the pressure up to 104 Pa, some useful characteristics of molecular flow are available. The SCE is supplied to users with a calibration certificate described its molecular conductance. Users can introduce optional test gases with the known flow rate to their vacuum chamber through the SCE in their laboratories. The overview of the SCE, the calibration method and recommended practices are introduced. 相似文献
1000.
Khan A.K. Magoshi H. Matsumoto T. Fujita J. Furuhashi M. Imai M. Kurose Y. Sato M. Sato K. Yamashita Y. Kinying Kwan Duc-Ngoc Le Yu J.H. Trung Nguyen Yang S. Tsou A. Chow K. Shen J. Min Li Jun Li Hong Zhao Yoshida K. 《Solid-State Circuits, IEEE Journal of》2001,36(11):1775-1784
A 150-MHz graphics rendering processor with an integrated 256-Mb embedded DRAM, delivering a rendering rate of 75 M polygons/s, is presented, 287.5 M transistors are integrated on a 21.3×21.7 mm 2 die in a 0.18-μm embedded DRAM CMOS process with six layers of metal. Design methodologies for hierarchical electrical and physical design of this very large-scale IC, including power distribution, fully hierarchical timing design, and verification utilizing a newly developed nonlinear model, clock design, propagation delay, and crosstalk noise management in multi-millimeter RC transmission lines, are presented 相似文献