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201.
T Kamei GP Hamlin BM Chapman AL Burkhardt JB Bolen MJ Soares 《Canadian Metallurgical Quarterly》1997,57(6):1302-1311
A specific method for pancreatic elastase II activity analysis was developed. True elastase II activity could be discriminated from that of elastase I and chymotrypsin. The postnatal development of four pancreatic proteases in the duodenal juice of children and in the pancreatic homogenates of calves and piglets was measured. The study was carried out on patients without (14 children) and with (5 children) pancreatic insufficiency. Calves and piglets were either milk-fed or weaned until slaughter at different ages. Profiles of enzyme development were globally similar in milk-fed piglets and calves, while in children without pancreatic insufficiency, no significant change was observed between 4 and 168 months. In children with pancreatic insufficiency, enzyme activity was low. In animals, elastase II and chymotrypsin activities were maximal at birth, decreased with age, and probably were associated with the digestion of milk protein. In contrast, elastase I and trypsin activities increased markedly after weaning in connection with the intake of solid food. 相似文献
202.
Kamei K. Kawasaki H. Chigira T. Nakanisi T. Kawabuchi K. Yoshimi M. 《Electronics letters》1981,17(13):450-451
Quarter-micron gate low-noise GaAs MESFETs have been developed by delineating gate electrodes by an electron-beam lithography technique and by using high-purity epiwafers prepared by a metal-organic-chemical vapour deposition (MOCVD) technique. At 18 GHz, a noise figure of 1.75 dB with an associated gain of 8.5 dB and a maximum available gain of 11 dB were obtained at drain currents of 10 mA and 30 mA, respectively. This is the lowest noise figure yet reported for low-noise GaAs MESFETs. 相似文献
203.
J Kamei Y Iwamoto M Misawa H Nagase Y Kasuya 《Canadian Metallurgical Quarterly》1994,254(1-2):113-117
The antinociceptive effect of L-arginine in streptozotocin-induced diabetic mice was examined. Although s.c. administration of L-arginine produced a dose-dependent inhibition of the tail-flick response in both non-diabetic and diabetic mice, the antinociceptive response was greater in diabetic mice than in non-diabetic mice. The antinociceptive effects of L-arginine in both diabetic and non-diabetic mice were significantly antagonized by s.c. administration of naltrindole, a selective delta-opioid receptor antagonist. However, neither beta-funaltrexamine, a selective mu-opioid receptor antagonist, nor nor-binaltorphimin ++, a selective kappa-opioid receptor antagonist, significantly affected the antinociceptive effect of L-arginine in diabetic and non-diabetic mice. These results suggest that L-arginine produces a marked antinociceptive effect in diabetic mice through the activation of delta-opioid receptors. 相似文献
204.
M Yamaguchi K Kamei T Koga M Akima T Kuroki N Ohi 《Canadian Metallurgical Quarterly》1993,36(25):4052-4060
A number of 4-substituted 2-[omega-(1-imidazolyl)alkyl]-1(2H)-phthalazinones were synthesized in order to develop agents possessing both thromboxane A2 synthetase inhibitory and bronchodilatory activities. The pharmacological evaluation of these compounds disclosed that they have both activities to various extents. Both activities were slightly dependent on the length of the 2-substituents and largely affected by the nature of the 4-substituents. Compounds bearing phenyl and thienyl groups exhibited relatively high and well-rounded activities. Among these compounds, 12j and 15f were found to be the most effective agents having well-rounded activities in vitro and in vivo. Introduction of a carboxyl group reduced both activities contrary to our expectation. 4-(3-Pyridyl)phthalazinone 18b was of particular interest because of unexpectedly high in vivo activities in spite of an absence of significant in vitro activities. 相似文献
205.
S Hojo J Fujita I Yamadori T Kamei T Yoshinouchi Y Ohtsuki H Okada S Bandoh Y Yamaji J Takahara T Fukui M Kinoshita 《Canadian Metallurgical Quarterly》1998,12(6):1404-1408
Lung cancer is a frequent complication in pulmonary fibrosis. Overexpression of p53 proteins has been demonstrated by immunostaining in bronchoepithelial cells in patients with idiopathic pulmonary fibrosis. However, it is still unclear whether this overexpressed p53 protein is wild-type or mutant. It was hypothesized that pulmonary fibrosis may be a precancerous lesion with deoxyribonucleic acid point mutations in bronchoepithelial cells. Mutations of the p53 gene were tested for by fluorescence-based single-strand conformation polymorphism (FSSCP), cloning-sequencing and immunostaining techniques. Out of 10 tissue samples that demonstrated overexpression of p53 protein by immunostaining, nine (90%) exhibited point mutations and eight (80%) exhibited heterogeneous point mutations of the p53 gene. The mutations found in pulmonary fibrosis were scattered throughout the central part of the p53 gene, and both guanine (G):cytosine (C) to adenine (A):thymine (T) and A:T to G:C transitions were frequently observed. In conclusion, frequent heterogeneous point mutations of the p53 gene were detected in pulmonary fibrosis. These mutations may have resulted from several types of deoxyribonucleic acid damage that occurred in bronchoepithelial cells and this may explain previous findings of a very high incidence of lung cancer complicating pulmonary fibrosis. 相似文献
206.
Dislocation dynamics theory for fatigue crack growth 总被引:1,自引:0,他引:1
Dislocation group dynamics theory is used to deduce a power type expression for fatigue crack growth. In general, the results reflect only a single rate process, and thus one activation energy which is small compared to those in usual rate processes. The frequency dependence for this power function type fatigue crack growth rate was also obtained, and yield reasonable agreement with experimental results from the literature. 相似文献
207.
The reaction mechanism of V2O5 xerogel and the electrode properties of V2O5/carbon composites in an aqueous electrolyte solution were examined to obtain high-performance electrodes for rechargeable proton batteries. Based on the results of the chemical analysis of the electrode, proton intercalation is suggested to be the dominant reaction mechanism. By using the relationship between the capacity and current density of a thin-film electrode consisting of V2O5 xerogel, the diffusion coefficient in the V2O5 xerogel was determined to be 8 ± 1 × 10?11 cm2 s?1. The V2O5/carbon composite electrode was prepared by drying a homogeneous dispersion of carbon particles in the V2O5 sol. The composite electrodes showed a large capacity of 460 mAh g?1 at a current density of 1 A g?1 and maintained a relatively large capacity of 160 mAh g?1 at 100 A g?1. These properties were attributed to the homogeneous microstructure of the V2O5/carbon composites. The V2O5/carbon composite electrodes were thus revealed as high-performance electrodes with large capacities and excellent high-rate capabilities. 相似文献