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排序方式: 共有535条查询结果,搜索用时 15 毫秒
491.
492.
Tomoyoshi Fuchise Hideki Kishimura Haruo Sekizaki Yoshiyuki Nonami Gaku Kanno Sappasith Klomklao Soottawat Benjakul Byung-Soo Chun 《Food chemistry》2009
Trypsins from the pyloric ceca of Pacific cod (Gadus macrocephalus) (GM-T) and saffron cod (Eleginus gracilis) (EG-T) were purified by gel filtration on Sephacryl S-200 and Sephadex G-50. The final enzyme preparations were nearly homogeneous on SDS–PAGE and the molecular weights of both enzymes were estimated to be approximately 24 kDa by SDS–PAGE. The specific trypsin inhibitors, soybean trypsin inhibitor and TLCK, strongly inhibited the activities of GM-T and EG-T. The optimum pH and optimum temperature of both trypsins were around pH 8.0 and 50 °C, respectively, using Nα-p-tosyl-l-arginine methyl ester as substrate. The GM-T and EG-T were unstable above 30 °C and below pH 5.0, and they were stabilised by calcium ion. The N-terminal amino acid sequences of GM-T (IVGGYECTRHSQAHQVSLNS) and EG-T (IVGGYECPRHSQAHQVSLNS) were found. The percentage of hydrophobic amino acid in the N-terminal 20 amino acids sequences of these cold-zone fish trypsins was lower (28%) than those of temperate-zone fish trypsins (34%), tropical-zone fish trypsins (37%) and mammalian trypsins (34%). Whereas the content of charged amino acids in the GM-T and EG-T was relatively higher than those of trypsins from temperate-zone fish, tropical-zone fish and mammals. Moreover, the GM-T catalyzed synthesis of Nα-(tert-butoxycarbonyl)-l-alanyl-l-alanine-p-nitroanilide (Nα-Boc-l-Ala-l-Ala-pNA) has been studied by using Nα-(tert-butoxycarbonyl)-l-alanine-p-guanidinophenyl ester [Nα-Boc-l-Ala-OpGu (inverse substrate)] as acyl donor and l-alanine-p-nitroanilide (l-Ala-pNA) as acyl acceptor, respectively. 相似文献
493.
Yoshihiro Kanno Izuru Takewaki 《Computer Methods in Applied Mechanics and Engineering》2008,198(1):102-115
This paper presents a method for computing a minimal bound that contains the solution set to the uncertain linear equations. Particularly, we aim at finding a bounding ellipsoid for static response of structures, where both external forces and elastic moduli of members are assumed to be imprecisely known and bounded. By using the S-lemma, we formulate a semidefinite programming (SDP) problem which provides an outer approximation of the minimal bounding ellipsoid. Bounding ellipsoids are computed for nodal displacements of uncertain braced frames as the solutions of the presented SDP problems by using the primal-dual interior-point method. 相似文献
494.
495.
Noriyuki Sonoyama Kosuke Iwase Hironori Takatsuka Tadaaki Matsumura Nobuyuki Imanishi Yasuo Takeda Ryoji Kanno 《Journal of power sources》2009
LiMn2O4 epitaxial thin films were synthesized on SrTiO3:Nb(1 1 1) and Al2O3(0 0 1) single crystal substrates by pulsed laser deposition (PLD) method and the electrochemical properties were discussed comparing with that of amorphous LiMn2O4 film on polycrystalline Au substrate. LiMn2O4 epitaxial film showed only a single plateau in charge–discharge curves and a single redox peak at the corresponding voltage of cyclic voltammograms. This phenomenon seems to originate from the effect of the epitaxy: the film is directly connected with the substrate by the chemical bond and this connection would suppress the phase transition of LixMn2O4 film during lithium (de-)intercalation. The discharge voltage of LiMn2O4 epitaxial film on SrTiO3 was lower than that of LiMn2O4 film on Al2O3. This lowered discharge voltage may be caused by the electronic interaction between LiMn2O4 film and SrTiO3:Nb n-type semiconductor substrate. 相似文献
496.
497.
Contribution of Na+/Ca2+ exchanger in maintaining [Ca2+]c at a stable state in rat pancreatic islets
The effects of lowering extracellular Na+ concentration [Na+]o, on cytosolic Ca2+ concentration, [Ca2+]c were examined by a microfluorimetric method using fura-2 in perifused preparations of isolated rat pancreatic islets. The total replacement of extracellular Na+ (Na+o) by equimolar N-methyl-D-(--)-glucamine caused a rapid rise in [Ca2+]c, and partial replacement of Na+o resulted in correlative rises in [Ca2+]c in accordance with the magnitude of reduced [Na+]o. The rise in [Ca2+]c induced by Na+o removal was strongly inhibited in the Ca2+o-deficient environment or by Ni2+. The [Ca2+]c rise, however, remained almost unchanged in the presence of nifedipine or SK&F 96365, and was enhanced by the addition of ouabain. The electrochemical gradients for Ca2+ (delta mu Ca2+) and Na+ (delta mu Na+) were calculated to be 39.08 and 12.8 kJ/mol, respectively, in this study, indicating a stoichiometry of 3Na+: 1 Ca2+. These results indicate that, in rat pancreatic islets, the rise in [Ca2+]c induced by lowering [Na+]o is mainly due to Ca2+ entry medicated by the Na+/Ca2+ exchanger operating with the stoichiometry of 3Na+:1 Ca2+, and that the Na+/Ca2+ exchanger plays an important role in maintaining stable-state [Ca2+]c. 相似文献
498.
Masayoshi Kobayashi Hideaki Kobayashi Tohru Kanno 《Chemical Engineering Communications》1988,66(1):23-27
The mode of transient response curves in CO oxidation on ZnO is drastically changed to a false start, an overshoot or an instantaneous mode, depending on the concentration region of CO. These characteristic modes and the anomalous steady state rate data which show maximum and minimum are consistently explained by the two reaction pathways model. 相似文献
499.
H Kanno H Fujii A Hirono Y Ishida S Ohga Y Fukumoto K Matsuzawa S Ogawa S Miwa 《Canadian Metallurgical Quarterly》1996,88(6):2321-2325
We report here two new cases of glucose phosphate isomerase (GPI) deficiency associated with hemolytic anemia and present the results of molecular analysis of the five Japanese GPI variants. A Japanese girl (GPI Fukuoka) had an episode of prolonged neonatal jaundice and at 3 years of age was admitted due to acute hemolytic crisis occurring with upper respiratory tract infection. Red blood cell (RBC) GPI activity was decreased to 11.8% of normal and the reduced glutathione (GSH) level of RBCs was slightly decreased. A 54-year-old Japanese man (GPI Iwate) was hospitalized due to chronic active hepatitis, and compensated hemolysis was noted. RBC GPI activity of the proband was decreased to 18.8%, and the GSH content was about half of the normal mean value. Sequencing of the reticulocyte GPIcDNA showed homozygous missense mutations 1028CAG-->CGG (343Gln-->Arg), 14ACC-->A7C (5Thr-->lle), 671ACG-->A7G (224Thr-->Met), and 1615GAC-->AAC (539Asp-->Asn) in GPI Narita, GPI Matsumoto, GPI Iwate, and GPI Fukuoka, respectively. We also identified GPI Kinki as a compound heterozygote of 1124ACA-->AGA(375Thr-->Arg)/ 1615GAC-->AAC(539Asp-->Asn). Our findings, together with the previous results of other investigators, showed that the GPI gene mutations so far identified were heterogeneous, although most GPI variants had common biochemical characteristics such as heat instability and normal kinetics. Several amino acid substitutions were identified in the proximity of the catalytically important amino acid residues such as Ser/Asp 159/160, Asp341, and Lys518, which have been identified in the structural analysis of the pig GPI. The molecular characterization of human GPI variants, therefore, may provide new insights into the genotype-phenotype correlation of GPI deficiency as well as the structure-function relationship of this enzyme. 相似文献
500.