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101.
T Suzuki T Hayashi Y Nonaka M Hirano T Nomura I Miyazawa F Ishikawa T Kakiuchi 《Canadian Metallurgical Quarterly》1996,37(12):1389-1394
Hemolytic anemia and possible aplastic crisis with symptoms including jaundice, general fatigue and dark urine developed in a man being treated only by lansoprazole. Five days later, he was treated with antibiotics. The next day, he was admitted to our hospital because of jaundice. On admission, the hemoglobin was 14.0 g/dl, reticulocyte count 8/1000, platelets 79 x 10(9)/l and total bilirubin 12.4 mg/dl (indirect bilirubin 9.5 mg/dl). The above medications were discontinued. The direct Coombs antiglobulin test was positive. Examination of the complement revealed a C3 fiter at the upper limit of normal and an increased C4 and CH50. Three days after admission, he had a severe anemia. The hemoglobin was 3.3 g/DL. We thought it possible that aplastic crisis had followed the hemolytic anemia induced by lansoprazole. He was treated with blood transfusions and corticosteroids. He recovered from anemia within three weeks. Exhaustive studies to identify the cause of the hemolytic anemia were undertaken with negative results. We detected IgG antibody to lansoprazole. We believe that the hemolytic anemia was induced by lansoprazole. 相似文献
102.
T Seya M Nomura Y Murakami NA Begum M Matsumoto S Nagasawa 《Canadian Metallurgical Quarterly》1998,1(5):809-816
OBJECT: In this retrospective study, the authors analyzed the frequency, anatomical distribution, and appearance of traumatic brain lesions in 42 patients in a posttraumatic persistent vegetative state. METHODS: Cerebral magnetic resonance (MR) imaging was used to detect the number of lesions, which ranged from as few as five to as many as 19, with a mean of 11 lesions. In all 42 cases there was evidence on MR imaging of diffuse axonal injury, and injury to the corpus callosum was detected in all patients. The second most common area of diffuse axonal injury involved the dorsolateral aspect of the rostral brainstem (74% of patients). In addition, 65% of these patients exhibited white matter injury in the corona radiata and the frontal and temporal lobes. Lesions to the basal ganglia or thalamus were seen in 52% and 40% of patients, respectively. Magnetic resonance imaging showed some evidence of cortical contusion in 48% of patients in this study; the frontal and temporal lobes were most frequently involved. Injury to the parahippocampal gyrus was detected in 45% of patients; in this subgroup there was an 80% incidence of contralateral peduncular lesions in the midbrain. The most common pattern of injury (74% in this series) was the combination of focal lesions of the corpus callosum and the dorsolateral brainstem. In patients with no evidence of diffuse axonal injury in the upper brainstem (26% in this series), callosal lesions were most often associated with basal ganglia lesions. Lesions of the corona radiata and lobar white matter were equally distributed in patients with or without dorsolateral brainstem injury. Moreover, cortical contusions and thalamic, parahippocampal, and cerebral peduncular lesions were also similarly distributed in both groups. CONCLUSIONS: The data indicate that diffuse axonal injury may be the major form of primary brain damage in the posttraumatic persistent vegetative state. In addition, the authors demonstrated in this study that MR imaging, in conjunction with a precise clinical correlation, may provide useful supportive information for the accurate diagnosis of a persistent vegetative state after traumatic brain injury. 相似文献
103.
Biocatalytic Synthesis of Nitriles through Dehydration of Aldoximes: The Substrate Scope of Aldoxime Dehydratases 下载免费PDF全文
Tobias Betke Jun Higuchi Philipp Rommelmann Keiko Oike Dr. Taiji Nomura Prof.Dr. Yasuo Kato Prof.Dr. Yasuhisa Asano Prof.Dr. Harald Gröger 《Chembiochem : a European journal of chemical biology》2018,19(8):768-779
Nitriles, which are mostly needed and produced by the chemical industry, play a major role in various industry segments, ranging from high‐volume, low‐price sectors, such as polymers, to low‐volume, high‐price sectors, such as chiral pharma drugs. A common industrial technology for nitrile production is ammoxidation as a gas‐phase reaction at high temperature. Further popular approaches are substitution or addition reactions with hydrogen cyanide or derivatives thereof. A major drawback, however, is the very high toxicity of cyanide. Recently, as a synthetic alternative, a novel enzymatic approach towards nitriles has been developed with aldoxime dehydratases, which are capable of converting an aldoxime in one step through dehydration into nitriles. Because the aldoxime substrates are easily accessible, this route is of high interest for synthetic purposes. However, whenever a novel method is developed for organic synthesis, it raises the question of substrate scope as one of the key criteria for application as a “synthetic platform technology”. Thus, the scope of this review is to give an overview of the current state of the substrate scope of this enzymatic method for synthesizing nitriles with aldoxime dehydratases. As a recently emerging enzyme class, a range of substrates has already been studied so far, comprising nonchiral and chiral aldoximes. This enzyme class of aldoxime dehydratases shows a broad substrate tolerance and accepts aliphatic and aromatic aldoximes, as well as arylaliphatic aldoximes. Furthermore, aldoximes with a stereogenic center are also recognized and high enantioselectivities are found for 2‐arylpropylaldoximes, in particular. It is further noteworthy that the enantiopreference depends on the E and Z isomers. Thus, opposite enantiomers are accessible from the same racemic aldehyde and the same enzyme. 相似文献
104.
Kotohiro Nomura 《大分子材料与工程》2019,304(9)
Acyclic diene metathesis polymerization using ruthenium–carbene catalysts affords defect‐free, high molecular weight poly(arylene vinylene)s containing all trans olefinic double bonds. The exclusive end‐functionalization in the resultant poly(fluorene vinylene)s or poly(phenylene vinylene)s can be attained by treating the vinyl end groups using a molybdenum–alkylidene catalyst/reagent (through olefin metathesis) followed by addition of various aldehydes (Wittig‐type coupling). Some of these end‐modified conjugated materials display unique emission properties, which are different from the original ones, through an interaction (energy transfer or structural change in the excited state) between the conjugated main chain and the end groups [oligo(thiophene)s, F‐BODIPY, etc.]. Exclusive synthesis of well‐defined, all‐trans end‐functionalized oligo(2,5‐dialkoxy‐1,4‐phenylene vinylene)s [(oligo(phenylene vinylene), alkoxy = O(CH2)2OSii Pr3, up to 31 repeat units] is demonstrated by adopting a stepwise synthetic approach (olefin metathesis and the subsequent Wittig‐type cleavage). It is clearly demonstrated that their optical properties (especially the fluorescence spectra including photoluminescence quantum yields) are strongly affected by the end groups as well as the conjugation repeat units. 相似文献
105.
Dr. Takuya Kobayakawa Kento Ebihara Yuzuna Honda Dr. Masayuki Fujino Dr. Wataru Nomura Prof. Naoki Yamamoto Dr. Tsutomu Murakami Prof. Hirokazu Tamamura 《Chembiochem : a European journal of chemical biology》2019,20(16):2101-2108
C34, a 34-mer fragment peptide, is contained in the HIV-1 envelope protein gp41. A dimeric derivative of C34 linked through a disulfide bridge at its C terminus was synthesized and found to display potent anti-HIV activity, comparable with that of a previously reported PEGylated dimer of C34REG. The reduction in the size of the linker moiety for dimerization was thus successful, and this result might shed some light on the mechanism of the suppression of six-helix bundle formation by these C34 dimeric derivatives. Addition of a Gly-Cys(CH2CONH2)-Gly-Gly motif at the N-terminal position of a C34 monomeric derivative significantly increased the anti-HIV-1 activity. This moiety functions as a new pharmacophore, and this might provide a useful insight into the design of potent HIV-1 fusion inhibitors. 相似文献
106.
Sinterability of various high-purity magnesium oxide powders 总被引:3,自引:0,他引:3
Kiyoshi Itatani Masayuki Nomura Akira Kishioka Makio Kinoshita 《Journal of Materials Science》1986,21(4):1429-1435
The sinterability of high-purity MgO powders with different production histories was investigated to make clear the relationship between the powder characterization, the densification processes, and the changes in microstructure both with increasing temperature at a rate of 10° C min–1 and at a fixed temperature of 1450° C for 5 h. The densification behaviour and the changes in microstructure of these compressed bodies were affected chiefly by their original surface activity and degree of agglomeration, depending on the production histories: (i) the ultra-fine and well-dispersed powder prepared by the vapour-phase oxidation process showed that densification proceeded with an appreciable grain growth with few closed pores remaining; (ii) powder derived from the sea-water magnesia process showed that the densification behaviour was affected by the species of magnesium salt, i.e. basic magnesium carbonate or magnesium hydroxide, used as a precursor; however, whichever magnesium salt was used, its sintered compact showed similar closed porosities and grain-size distributions; (iii) powder derived from the spark-discharge process contained skeletons of the original Mg(OH)2 particles; however, the densification proceeded gradually with slow grain growth, reflecting the fact that the powder has a moderate surface area (36 m2 g–1). The sintered compact from (iii) had a small closed porosity and the smallest grain-size distribution among the compacts used in this investigation. 相似文献
107.
Satoshi Fukuta Keita Ogawa Masaki Nomura Mariko Yamasaki Yasutoshi Sasaki 《Holz als Roh- und Werkstoff》2017,75(3):429-437
In this study, the potential of wood-only (metal-free) load-bearing walls was proposed and tested based on the idea of using the same type of material throughout wherever possible while improving basic properties such as strength, sound insulation, and heat insulation. Specifically, a technique was tested of combining pressure sensitive adhesive tape and wood dowels in place of nails for load-bearing structures with panel reinforcement represented by wood-frame construction. For this paper, its strength was evaluated by conducting in-plane shear tests, which revealed that the initial rigidity and maximum load of the proposed test specimens were greater than that of specimens using nails for jointing. However, the shear load factor, which is calculated based on some strength parameters and which forms the foundation of housing strength design, was slightly lower than that of the nail-jointed specimen. This was because there was a large decline in post-collapse resistance and a lower calculated absorbed energy caused by brittleness. The early detachment of panels was also revealed as a problem in the tests. 相似文献
108.
Latent heat storage (LHS) using phase change materials is quite attractive for utilization of the exergy of solar energy and industrial exhaust heat because of its high‐heat storage capacity, heat storage and supply at constant temperature, and repeatable utilization without degradation. In this article, general LHS technology is outlined, and then recent advances in the uses of LHS for high‐temperature applications (over 100 °C) are discussed, with respect to each type of phase change material (e.g., sugar alcohol, molten salt, and alloy). The prospects of future LHS systems are discussed from a principle of exergy recuperation. In addition, the technologies to minimize exergy loss in the future LHS system are discussed on the basis of the thermodynamic analysis by ‘thermodynamic compass’. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
109.
Y. Aoki Y. Wada A. Ogino M. Saitoh R. Nomura Y. Okuda 《Journal of Low Temperature Physics》2005,138(3-4):783-788
No Heading The transverse acoustic response in the B phase of superfluid 3He has been measured using an AC-cut quartz transducer at a pressure of 17.0 bar. The measurements were performed by a CW bridge method at a frequency of 9.3 MHz utilizing a quadrature hybrid and a high-frequency lock-in amplifier. By sweeping frequency around the resonance frequency of the transducer, in-phase and quadrature responses of the resonance were obtained from the output of the lock-in amplifier. We successfully separated the quality factor and the resonance frequency. Quality factor of the transducer had a small dip just below Tc and increased as n by cooling, while its resonance frequency decreased sharply at Tc and gradually recovered to the normal state value in the low temperature limit.PACS numbers: 67.57.Jj, 43.58.+z. 相似文献
110.
A consistent grayscale‐free topology optimization method using the level‐set method and zero‐level boundary tracking mesh 下载免费PDF全文
Shintaro Yamasaki Atsushi Kawamoto Tsuyoshi Nomura Kikuo Fujita 《International journal for numerical methods in engineering》2015,101(10):744-773
This paper proposes a level‐set based topology optimization method incorporating a boundary tracking mesh generating method and nonlinear programming. Because the boundary tracking mesh is always conformed to the structural boundary, good approximation to the boundary is maintained during optimization; therefore, structural design problems are solved completely without grayscale material. Previously, we introduced the boundary tracking mesh generating method into level‐set based topology optimization and updated the design variables by solving the level‐set equation. In order to adapt our previous method to general structural optimization frameworks, the incorporation of the method with nonlinear programming is investigated in this paper. To successfully incorporate nonlinear programming, the optimization problem is regularized using a double‐well potential. Furthermore, the sensitivities with respect to the design variables are strictly derived to maintain consistency in mathematical programming. We expect the investigation to open up a new class of grayscale‐free topology optimization. The usefulness of the proposed method is demonstrated using several numerical examples targeting two‐dimensional compliant mechanism and metallic waveguide design problems. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献