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排序方式: 共有760条查询结果,搜索用时 15 毫秒
1.
Masaaki Miyamoto Hiroyuki Koike Toshio Sada Yasuteru Ijima Junichiro Fukushige Norio Nakamura 《Lipids》1991,26(12):1316-1319
Platelet-activating factor (PAF) is a potent inflammatory mediator which is released by various inflammatory cells and produced
by certain tissues, including the kidney. PAF has been shown to increase glomerular permeability to protein and to decrease
glomerular filtration rate (GFR) by contracting mesangium. On the basis of these observations, it has been suspected that
PAF may play a role as mediator of glomerular damage in glomerular nephritis. To examine this possibility, we studied the
effects of a specific PAF antagonist, R-75,317, on the development of an experimental model of anti-glomerular basement membrane
(anti-GBM) glomerulonephritis. Glomerulonephritis was initiated by injecting rabbit anti-rat GBM serum into rats. Proteinuria
gradually developed after serum injection, plateaued at week 2, and remained at the high level of week 2 throughout the experimental
period (6 wk). Chronic treatment with R-75,317 (10 mg/kg/day i.p.) tended to delay the onset of proteinuria and significantly
accelerated the recovery phase. Creatinine clearance (Ccr) fell to 40% at week 3. R-75,317 treatment completely prevented
this decline of Ccr. Histological changes in this model (glomerular hypertrophy, proliferation of mesangial matrix and interstitial
fibrosis) were also ameliorated by the R-75,317 treatment. The results suggest that PAF may play a role in the development
of glomerulonephritis and that PAF antagonists could be used in the treatment of human renal disease.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, May 1989. 相似文献
2.
Norio Tsubokawa 《Polymer Bulletin》1989,22(1):55-62
Summary The ring-opening polymerization of 2-oxazolines (OXZs) was found to be initiated by chloromethyl groups introduced onto carbon black surface. The introduction of chloromethyl groups onto the surface was achieved by the reaction of carbon black with 3,3-bischloromethylbenzoyl peroxide in carbon tetrachloride. During the polymerization, poly-OXZs were grafted from carbon black based on the propagation of the polymers from the surface: percentage of grafting increased with an increase of conversion and reached 40–60%. The polymerization was accelerated by the addition of potassium iodide. Poly-OXZ-grafted carbon black produced stable colloidal dispersions in both hydrophobic and hydrophilic solvents. 相似文献
3.
Reiji Hattori Shuhei Yamada Yoshitomo Masuda Norio Nihei 《Journal of the Society for Information Display》2004,12(1):75-80
Abstract— We have developed new powder materials that exhibit liquid behavior, which can lead to the realization of novel bistable and reflective displays having paper‐white appearance, high contrast, and quick response. Two types of display were demonstrated, one had 160 × 160 array of pixels and the other had 320 × 320 in a 3.1‐in.‐diagonal viewable image size corresponding to 66 and 132 dpi, respectively. These displays were driven by passive‐matrix addressing. The displays showed a reflectivity of more than 41%, a contrast more than 1:10, and a pixel response time of less than 0.2 msec. The seven‐segment display for use in clocks was also demonstrated. 相似文献
4.
This paper describes the effect of ultra-thin liquid lubricant films on air bearing dynamics and flyability of less than 10 nm spacing flying head sliders in hard disk drives. In particular, the effect of non-uniform lubricant film distributions on head/disk interface dynamics are studied. The disks with lubricant on one half of disk surface thicker than the other half were used in this study. The dynamics of sliders is monitored using acoustic emission (AE) and the interactions between the slider and disk are investigated experimentally. The disks were also examined with a scanning micro-ellipsometer before and after each test. Complicated slider responses were observed and clarified. In addition, it was found that the periodic lubricant film thickness modulations or non-uniformity caused by the slider-disk contact interactions could be observed. It is suggested that this lubricant film thickness non-uniformity will be one of the technical issues in order to achieve ultra-low head/disk contact interface of less than 10 nm. 相似文献
5.
Takuo Suganuma SungDoke Lee Tetsuo Kinoshita Norio Shiratori 《New Generation Computing》2001,19(2):173-191
In this paper, we propose an agent architecture to improve flexibility of a videoconference system with strategy-centric adaptive
QoS (Quality of Service) control mechanism. The proposed architecture realizes more flexibility by changing their QoS control
strategies dynamically. To switch the strategies, system considers the properties of problems occurred on QoS and status of
problem solving process. This architecture is introduced as a part of knowledge base of agent that deals with cooperation
between software module of videoconference systems. We have implemented the mechanism, and our prototype system shows its
capability of flexible problem solving against the QoS degradation, along with other possible problems within the given time
limitation. Thus we confirmed that the proposed architecture can improve its flexibility of a videoconference system compared
to traditional systems.
Takuo Suganuma, Dr.Eng.: He is a research associate of Research Institute of Electrical Communication of Tohoku University. He received a Dr.Eng.
degree from Chiba Institute of Technology in 1997. His research interests include agent-based computing and design methodology
for distributed systems. He is a member of IPSJ, IEICE and IEEE.
SungDoke Lee: He is a Ph.D. Student in the Graduate School of Information Sciences in Tohoku University. He received his MEng degree at
Chonbuk National University, Korea in 1991. His research interests include Flexible Network and Knowledge of Agent.
Tetsuo Kinoshita, Dr.Eng.: He is an associate professor of Research Institute of Electrical Communication of Tohoku University. He received a Dr.Eng.
degree in information engineering from Tohoku University, Japan. His research interests include knowledge engineering, cooperative
distributed processing and agent-based computing. He received the the IPSJ Best Paper Award in 1997, etc. He is a member of
IPSJ, IEICE, JSAI, AAAI, ACM and IEEE.
Norio Shiratori, Dr.Eng.: After receiving his Dr.Eng degree at Tohoku University, he joined the Research Institute of Electrical Communication of
Tohoku University in 1977, and is now a professor at the same University. He has been engaged in research on distributed processing
system, and flexible intelligent network. He received the 25th Anniversary of IPSJ Memorial Prize-Winning Paper Award in 1985,
the 6th Telecommunications Advancement Foundation Incorporation Award in 1991, the Best Paper Award of ICOIN-9 in 1994, the
IPSJ Best Paper Award in 1997, etc. He has been named a Fellow of the IEEE for his contributions to the field of computer
communication networks. 相似文献
6.
The ion-selective property of hydrous ferric oxide precipitate films has been investigated by measuring membrane potentials which arise across precipitate membranes of hydrous ferric oxide with and without adsorbed MoO42? ions and of ferric molybdate in solutions of NaCl, KCl, MgCl2, CaCl2, BaCl2, AlCl3, and FeCl3. The hydrous ferric oxide membrane was only permeable to Cl? ions in chloride solutions, whereas the membrane with adsorbed MoO42? ions was permeable to cations in NaCl and KCl solutions, and to both Cl? and cations in the presence of multivalent cations. The ferric molybdate membrane was permeable to Cl? and cations in NaCl and KCl solutions, and only to Cl? ions in the presence of multivalent cations. It is suggested that in chloride solutions, the corrosion of iron covered with a precipitate film of hydrous ferric oxide is accelerated by enrichment of Cl? ions under the film, which may decrease the local pH and introduce a positive diffusion potential in the film. The adsorption of MoO42? ions on the oxide changes the ion-selectivity of the precipitate film from the anion-selective to the cation-selective in solutions of NaCl and KCl. This cation-selectivity of the film may inhibit the corrosion of iron, because of H+ ions diffusing out of the film. The inhibitive effect of MoO42? ions would be reduced in the presence of multivalent cations. 相似文献
7.
Masaharu Takeda Hiroyuki Hiraishi Toshikazu Takesako Sumio Tanase Norio Gunge 《Yeast (Chichester, England)》1996,12(3):241-246
The 36K protein attached at the 5′ end of the linear DNA plasmid pGKL2 from the yeast Kluyveromyces lactis was first purified and characterized. The terminal protein was purified from cells (1 kg wet weight) by ammonium sulphate precipitation and two rounds of centrifugation to equilibrium in CsCl gradients. The pGKL2 was present only in the post-microsomal supernatant. Approximately 10 mg of the purified pGKL2 was recovered and digested with DNase I. The terminal protein (final ca. 0·8 mg) was homogeneous by electrophoresis and we determined the N-terminal amino acid sequence up to ten residues, showing that it existed in the cryptic N-terminal domain of pGKL2-ORF2 (DNA polymerase) sequence. 相似文献
8.
Amizuka N Shimomura J Li M Seki Y Oda K Henderson JE Mizuno A Ozawa H Maeda T 《Journal of electron microscopy》2003,52(6):503-513
Previous studies have reported enhanced osteoclastogenesis, increased bone resorption and osteoporosis in osteoprotegerin (OPG)-deficient mice. In the present study, we show that the tibial epiphyses contain abundant, thin trabeculae lined with numerous osteoclasts and cuboidal osteoblasts. The increase in osteoblasts and osteoclasts was associated with a dramatic increase in calcein labelling of the mineralization fronts and replacement of much of the intertrabecular marrow with numerous alkaline phosphatase-positive preosteoblasts. Furthermore, the discrete, linear cement lines seen in wild-type mice were replaced by a randomly oriented meshwork of cement lines that were stained intensely for tartrate-resistant acid phosphatase and osteopontin in the OPG-/- mice. These indices of accelerated bone remodelling in mutant bone were associated with irregular trabecular surfaces, a disorganized collagen matrix interspersed with amorphous ground substance and numerous fissures between old and new bone. In total, these observations indicate that enhanced osteoclastic activity in OPG-/- epiphyses led to a coupled increase in osteoblast differentiation and activity and an increase in bone remodelling. The high bone turnover, disorganized matrix and impaired attachment of new to old bone in the cement lines in OPG-/- mice appear to cause bone fragility. 相似文献
9.
Makoto Murakami Ken-ichi Suzuki Hideki Maeda Tetsuo Takahashi Akira Naka Norio Ohkawa Mamoru Aiki 《Optical Fiber Technology》1997,3(4):320-338
Optical amplifier techniques have led to the installation of large-capacity submarine systems and further capacity increases seem likely. This paper reviews the FSA submarine system, which flexibly operates at both 2.5 and 10 Gb/s and offers maximum transmission capacity of 60 Gb/s for commercial use. The system configuration as well as its characteristics and upgradability will be introduced, including measurement results on time-division-multiplexing/wavelength-division-multiplexing (TDM–WDM) transmission at bit rates of 10 and 20 Gb/s using non-return-to-zero or soliton pulses. To further increase transmission capacity, TDM–WDM techniques that permit more than 10 Gb/s signal transmission in each data channel should be developed. Thus, pulse formats, which include non-return-to-zero, return-to-zero, or soliton pulses, and dispersion allocation in transmission fibers are significant issues. We introduce and discuss our recent results from high-speed (10 to 40 Gb/s) TDM–WDM signal transmission experiments with regard to the above aspects. 相似文献
10.
Debasish Chakraborty Goutam Chakraborty Norio Shiratori 《International Journal of Network Management》2003,13(5):321-335
In this paper we propose a QoS‐based routing algorithm for dynamic multicasting. The complexity of the problem can be reduced to a simple shortest path problem by applying a Weighted Fair Queuing (WFQ) service discipline. Using a modified Bellman–Ford algorithm, the proposed routing builds a multicast tree, where a node is added to the existing multicast tree without re‐routing and satisfying QoS constraints. With user defined life‐time of connection this heuristic algorthm builds multicast tree which is near optimum over the whole duration of session. Simulation results show that tree costs are nearly as good as other dynamic multicast routings that does not consider QoS. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献