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61.
T Tsushima Y Katoh Y Miyachi K Chihara A Teramoto M Irie Y Hashimoto 《Canadian Metallurgical Quarterly》1999,84(1):317-322
Several GH isoforms have been identified in pituitary and serum, the most abundant of which is the 22K human GH (hGH) isoform. The 20K hGH isoform is produced by alternative splicing of GH messenger ribonucleic acid and comprises approximately 10% of all GH in the pituitary. The physiological role of 20K hGH remains to be determined, partly because of the lack of a simple and specific assay. We have established sensitive enzyme-linked immunosorbent assays (ELISAs) specific to 20K and 22K hGH. To determine whether regulation of 20K hGH secretion is the same as that for 22K hGH, we measured serum concentrations of both species of hGH in normal subjects and patients with a variety of endocrine disorders. The serum levels of 20K hGH after overnight fasting was 118 +/- 178 pg/mL (n = 282) in normal women, significantly higher than that in normal men (64 +/- 170 pg/mL; n = 226). However, there was no difference in the proportion of 20K hGH to 20K plus 22K hGH between men (6.3 +/- 2.6%, mean +/- SD; n = 176) and women (6.3 +/- 2.1%; n = 263). No correlation was detected between the ratio of 20K hGH and age, body height, body weight, or body fat mass in normal subjects. The proportion of 20K hGH was significantly (P < 0.001) higher in patients with active acromegaly (9.2 +/- 2.2%; n = 33) and patients with anorexia nervosa (9.0 +/- 1.9; n = 8), both of which are characterized by chronic elevation of circulating GH levels. The proportion of 20K hGH in successfully treated acromegalic patients did not differ from that in normal subjects, suggesting that GH-producing pituitary tumors secrete a higher proportion of 20K hGH, or that a chronic excess of 22K hGH alters the MCR of 20K hGH. The values in patients with adult GH deficiency, hyperthyroidism, primary hypothyroidism, or GH-independent short stature did not differ from those in normal subjects. The 20K ratio did not change after acute GH provocative tests, such as the insulin tolerance test and the GHRH test. These results suggest that secretion of 20K hGH from the pituitary is under the same control as that of 22K hGH. This new assay may provide a tool for understanding the physiological or pathophysiological role of the 20K hGH isoform. 相似文献
62.
63.
Taizo Kojima Hideo Nakata Motohiko Kawagishi Taku Uehara 《Electrical Engineering in Japan》1998,123(1):32-42
This paper presents a framework for constructing databases for supervisory control systems. The proposed framework utilizes a generation-based approach and object-oriented framework libraries. In this framework, a database is designed for the target system from a design template, and the software for the database system is generated from the database design. The generated database system includes a domain-specific object system and a diagram and plant data editor, which provides effective data input functions. © 1998 Scripta Technica, Electr Eng Jpn, 123(1): 32–42, 1998 相似文献
64.
Hidehiko Okada Yositeru Tsuchinaga Ryozo Itoh Fujio Irie 《Electrical Engineering in Japan》1997,118(4):1-9
To scale up the capacity of an SMES for a practical application, it is necessary to adopt a high-voltage system, a large current system or a modular system. The first system is difficult because of the very low withstanding voltage of a superconducting coil and the second also involves difficulties such as multiple connections of many convertors on the dc side and large current conductors in the superconducting coil. The third system, composed of several modules with small-scale convertor units and element coils, might be a solution of the above difficulties. In this modular system, the module coils have magnetic linkage with one another. In this paper, the influence of magnetic linkage between coils of a modular SMES is investigated by computer simulation. The magnetic linkage varies with the number of modules and the type of connection of the coils. By the effect of this magnetic linkage, each module's coil current is different at the same power. The current and energy transfer characteristics are determined for discharge from one or more of 6 modules, consisting of 18 coils. The discussion deals with the case in which there is an unused module when quenching occurs. The transfer with the same current in all modules is shown by control of convertor power of the current feedback. © 1997 Scripta Technica, Inc. Electr Eng Jpn. 118 (4): 1–9, 1997 相似文献
65.
66.
Yuichiro TakimotoTaiki Kitta Hiroshi Irie 《International Journal of Hydrogen Energy》2012,37(1):134-138
We investigated the ability of the oxide ZnRh2O4 to serve as a solar H2-evolution photocatalyst due to the predicted potential of its conduction band bottom, which may allow thermodynamically favorable H2 evolution in spite of its small band-gap of 1.2 eV. ZnRh2O4 produced H2 in the presence of HCHO, but only scarcely in the presence of CH3OH, indicating that the potential of the valence band top of ZnRh2O4 lies at ∼0.1 V (vs. SHE). Thus, the conduction band bottom potential (∼−1.1 V) lies much more negative than the potential of H+/H2, allowing thermodynamically favorable H2 evolution. In addition, the irradiated-light-wavelength dependence of the quantum efficiency (QE) for H2 evolution was consistent with the solar spectrum, and the QE was quite high (∼27%), even at a wavelength of 770 ± 25 nm. Taken together, our findings indicate that ZnRh2O4 can utilize solar light effectively, not only the entire range of UV and visible light, but is also sensitive to infrared light. 相似文献
67.
Irie M 《Meat science》2001,57(1):19-22
Factors affecting the appearance of bovine fat were studied with a spectrophotometer using surface and transmittance optical probes and halogen and mercury lamps. Reflectance minima in the spectra of the fat were mainly derived from β-carotene and hemoglobin. The presence of deoxy- and met-hemoglobin darkened the fat color. There were wide differences in the transmittance measurements among the white colored fats. The extracted lipid had a lower reflectance than the adipose tissue but the grinding fat had higher reflectance. With ultraviolet light, the adipose tissue had a higher fluorescence, which strengthened the perceived whiteness compared to the extracted lipid. These results showed that the appearance of bovine fat is mainly affected by the absorbance of carotene and hemoglobin derivatives, the reflectance, transmittance, and fluorescence of lipids, and the reflectance and fluorescence of non-lipid components (connective tissue and cell membranes). 相似文献
68.
Abstract The acid-soluble lignin determination used in analyses of lignin by the sulfuric acid method was evaluated. The conventional UV spectrophotometric method using the absorption at 205 nm is appropriate for hardwoods, whereas for softwoods and bamboo the absorption at 205 nm should be corrected, since the absorption maximum is shifted to a shorter wavelength in sulfuric acid solution. Therefore, in the latter cases, the actual absorption maximum should be used. 相似文献
69.
Hiroshi Kamizuma Yukinori Akamine Taizo Yamawaki Kazuhiko Hikasa 《IEEJ Transactions on Electrical and Electronic Engineering》2013,8(1):49-55
A quad‐band (0.8, 1.7, 2, and 1.4 GHz) wideband code division multiple access (W‐CDMA) transceiver, which uses a divide‐by‐2.5 frequency divider in local parts of a direct‐conversion architecture, has been developed. Using the fractional‐2.5 frequency divider reduces the fractional bandwidth of the voltage‐controlled oscillator and avoids injection locking of the local RF synthesizer perfectly. This transceiver achieved 3% error‐vector magnitude and—46 dB ACLR, which satisfy the margin given in standard specifications. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
70.
Taizo Sano Masamichi Tsuji Nobuyuki Gokon Hiroshi Kaneko Yutaka Tamaura 《Journal of the American Ceramic Society》2000,83(10):2509-2514
Oxygen uptake and release of (Li,Mn) ferrite [LMF; (Li0.60 Mn1.20 Fe1.20 )1−δ O4 ; δ= 0.007 to 0.033] was investigated concerning the relations between redox reactions of ferrite and cation migration. Mössbauer spectroscopy and X-ray diffractometry showed that some of the Li+ and Fe3+ ions migrated from the A sites to the B sites of the spinel-type structure and Mn4+ ions migrated from the B sites to the A sites during oxygen uptake at 573 K. The cation-deficient LMF formed by the oxygen uptake released oxygen molecules in He gas only at 660 K. The cation migration during the oxygen release was in the opposite direction of the movement during oxygen uptake at 573 K. 相似文献