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81.
Lipid hydroperoxide may react with protein or amino phospholipid without secondary decomposition. We prepared a polyclonal antibody to lipid hydroperoxide-modified proteins using 13S-hydroperoxy-9Z, 11E-octadecadienoic acid-modified keyhole limpet hemocyanin (13-HPODE-KLH) as immunogen. The antibody recognized 13-HPODE-modified bovine serum albumin (BSA), but not aldehyde-modified proteins, such as malondialdehyde-modified BSA. The antibody also recognized adducts derived from 13-HPODE and 13S-hydroperoxy-9Z, 11E, 15Z-octadecatrienoic acid (13-HPOTRE(alpha)). The oxidized alpha-linolenic acid- and linoleate-protein adducts were recognized by the antibody. Oxidized phospholipid-protein adducts were scarcely recognized by the antibody. However, when ester bonds of phospholipids containing linoleic acid were hydrolyzed by alkaline treatment, the cross-reactivities appeared. The result suggests that a phospholipid hydroperoxide can react with a protein directly or indirectly, and a carboxyl terminal (COOH) of the lipid in an adduct was needed as an epitope. Oxidized LDL (ox-LDL) was prepared by the incubation of LDL with copper ion or 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH), and the formation of lipid hydroperoxide-modified apolipoprotein was confirmed using the antibody. A slight immunoreactivity was observed in ox-LDL without alkaline treatment. When the ox-LDL was treated with alkali to hydrolyze the ester bonds of the lipid, enhanced antigenicity appeared with time-dependency. The results suggest that lipid hydroperoxide-modified apolipoprotein was formed during the oxidation of LDL. 相似文献
82.
83.
Seah Winston Khoon‐Guan Takahashi Yutaka Hasegawa Toshiharu 《Telecommunication Systems》1998,10(3-4):243-268
In this paper, we analyse the message waiting times in a local area network (LAN) that uses the demand‐priority access method.
This is a priority‐based round‐robin arbitration method where the central controller (the repeater) polls its connected ports
to determine which have transmission requests pending and the requests' priority classes. We model it as a 2‐priority M/G/1 queue with multiple server vacations and switchover time between service periods. The service discipline is nonpreemptive
and the length of the switchover time is dependent upon the priority class of the preceding message served as well as that
of the message to be served next. We provide an approximate analysis for the waiting times of both message classes and derive
expressions for the Laplace–Stieltjes transforms (LST) of the stationary distributions and the mean waiting times. We conclude
with numerical and simulation results to show the applicability and accuracy of the analytical model.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
84.
All-optical bistable switching dynamics of 1.55-μm two-segment strained multiquantum-well (MQW) distributed-feedback (DFB) lasers were systematically studied both experimentally and theoretically. Some fundamental optical functionalities, including all-optical set-reset (flip-flop) operations, were demonstrated. The switching responses of these bistable lasers were studied, for the first time, with optical injection from a single-mode DFB laser, indicating that the switching dynamics based on gain quenching and absorption saturation are inherently different. A theoretical model including optical injection was developed to study these all-optical bistable switching characteristics in segmented bistable lasers. It was found that the nonuniform distribution of the photon density in the bistable laser cavity induced by optical injection was essential to perform the time-domain switching operations. Simulations showed a good agreement with experimental observations and indicated design improvements. Although the switching responses in the range of tens of picoseconds can be obtained with these bistable lasers, the maximum repetition frequency of the bistable systems would still be limited to the hundreds of megahertz due to the slow carrier recovery time (5 ns) of the lasers 相似文献
85.
T Aburano R Katada N Shuke W Yamamoto T Kawakami I Makino J Sato Y Ishikawa 《Canadian Metallurgical Quarterly》1997,11(4):335-338
The aim of this study was to estimate the incidence of melanoma in the Paris region in 1994 and analyse the main clinical and histological characteristics of these lesions. It took the form of a prospective inquiry, mailed to public and private pathology laboratories, to count as accurately as possible the number of new cases diagnosed by pathologists in the region during the 1994 calendar year. In all, 1089 newly diagnosed Clark level I to V melanomas (excluding precancerous melanosis of Dubreuilh) were studied. Parameters recorded included age, sex, Clark level and Breslow's thickness. The incidence per 100,000 inhabitants was 9.93 for melanoma and 8.62 for invasive melanoma. The female to male ratio was 1.6. Clark level I or thin (< 0.75 mm) melanomas represented 64.8% of the lesions. At the time of diagnosis, the females were significantly younger than the males (P = 0.004). Breslow's thickness increased with age and was significantly lower in women (P = 0.00005), especially those between 40 and 49 years old. The incidence of melanoma in the Paris region in 1994 was close to that observed during the preceding 5 years in England, Scotland and the French department of Haut-Rhin. It was 2.32 times higher for males and 1.69 times higher for females than the rates estimated for France for the period 1978-1982. 相似文献
86.
Nakamura M. Ueda H. Makino S. Yokotani T. Oshima K. 《Lightwave Technology, Journal of》2004,22(11):2631-2640
The construction of optical access networks is one of key issues to provide new broad-band services and emulation of legacy services. Passive optical network (PON) technologies realize sophisticated and economical optical access networks for these purposes. This paper summarizes requirements and technical and marketing trends for optical access networks. It also presents advantages of networking by PON technologies for optical access networks. Moreover, it clarifies issues to install and operate PON base optical access networks and proposes solutions for these issues. 相似文献
87.
Steady-state fluorescence anisotropy of diphenylhexatriene and n-(9-anthroyloxy)stearic acids (n=2,12) in rat liver microsomes
showed a marked increase in the early stages of enzymatically or non-enzymatically induced lipid peroxidation. The changes
in fluorescence anisotropy occurred in parallel with the formation of thiobarbituric acid-reactive substances (TBA-RS). Parallel
to these changes, the fluorescence emitted from peroxidized microsomes increased markedly in the early stages of lipid peroxidation.
In contrast to the changes in the fluorescence anisotropy and in the formation of TBA-RS, the fluorescence showed a continuing
increase over the three hr period of lipid peroxidation. Glucose-6-phosphatase was inactivated in the early stages of lipid
peroxidation, whereas NADH-cytochrome b5 reductase underwent a slow deactivation over three hr. The apparently slow deactivation of the peripheral protein may be
explained by the formation of fluorescent substances. 相似文献
88.
Nukaiyama Y. Takagi I. Ishihara H. Kudo A. Makino Y. Hosokawa N. 《Power Delivery, IEEE Transactions on》1994,9(4):1885-1891
Gas analysis provides a promising means for a diagnosis of gas-insulated equipment. Although many studies have been concentrated on SF6 gas decomposition, they were mostly related to the faults in GIS systems and not directly applicable to gas-insulated transformers, which have much more complicated material structure. An experimental survey on decomposition by-products at various abnormal conditions was carried out by use of simulation models to develop a diagnostic method for gas-insulated transformers based on gas and ion chromatograph analyses. Major components characteristic in each abnormality, such as SO2 on metal overheat, SO2F 2 on partial discharges, etc. were identified by the experiments 相似文献
89.
Ishikura S. Kurumada M. Terano T. Yamagami Y. Kotani N. Satomi K. Nii K. Yabuuchi M. Tsukamoto Y. Ohbayashi S. Oashi T. Makino H. Shinohara H. Akamatsu H. 《Solid-State Circuits, IEEE Journal of》2008,43(4):938-945
We propose a new 2-port SRAM with a single read bit line (SRBL) eight transistors (8 T) memory cell for a 45 nm system-on-a-chip (SoC). Access time tends to be slower as a fabrication is scaled down because of threshold voltage (Vt) random variations. A divided read bit line scheme with shared local amplifier (DBSA) realizes fast access time without increasing area penalty. We also show an additional important issue of a simultaneous read and write (R/W) access at the same row by using DBSA with the SRBL-8T cell. A rise of the storage node causes misreading. A read end detecting replica circuit (RER) and a local read bit line dummy capacitance (LDC) are introduced to solve this issue. A 128 bit lines - 512 word lines 64 kb 2-port SRAM macro using these schemes was fabricated by a 45 nm bulk CMOS low-standby-power (LSTP) CMOS process technology [1]. The memory cell size is 0.597 mum2. This 2-port SRAM macro achieves 7 times faster access time without misreading. 相似文献
90.
Keiichirou Yonezawa Alexander Hinderhofer Takuya Hosokai Kengo Kato Rintaro Makino Frank Schreiber Nobuo Ueno Satoshi Kera 《Advanced Materials Interfaces》2014,1(5)
The dependence of the energy level alignment (ELA) on structural defects at an organic/organic heterojunction (OOH) of perfluoropentacene (PFP)‐on‐diindenoperylene (DIP) was investigated using X‐ray scattering and ultraviolet photoelectron spectroscopy. The density of structural defects near the interface between the PFP and DIP layers was varied by changing the growth temperature of the DIP film. A direct relationship was found between the defect density and the ELA at the OOH; the ELA together with the change in the electrostatic potential (quasi‐interface dipole layer) at the OOH varies systematically with the defect density near the interface. This indicates that a key factor affecting the ELA is the electrostatic potential change across the OOH interface, which is produced by electron transfer from DIP occupied gap states to PFP unoccupied gap states. These gap states originate from the defects and are effectively controlled by adjusting the growth conditions of the organic films. As a result, the ELA at OOH interfaces can be controlled by the density of structural defect, which is important for organic devices employing OOHs, such as organic photovoltaic cells. 相似文献