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111.
T Saito K Ukai T Masuda T Nakagawa K Kimura M Fujii K Wakatsuki M Saeki H Kasai 《Canadian Metallurgical Quarterly》1997,47(12):1375-1382
The general pharmacological properties of a novel cholecystokinin-A antagonist, loxiglumide ((+/-)-4-(3,4-dichlorobenzamido)-N-(3-methoxypropyl)-N-pentylgl utaramic acid, CR 1505, CAS 107097-80-3) on central nervous system, autonomic nervous system, cardio-respiratory system, gastrointestinal system, hematological and miscellaneous systems were investigated in experimental animals. 1. Central nervous system: At a dose of 30 mg/kg, i.v. loxiglumide showed ptosis in one of 6 mice, but at doses of 3 and 10 mg/kg, i.v. no change on gross behavior in mice. Loxiglumide had no effect on locomotor activity and thiopental-induced hypnosis, anti-convulsive activity, analgesic activity in mice and rectal temperature changes in rats. 2. Autonomic nervous system: In vitro, loxiglumide at concentrations of 10(-4) and 3 x 10(-4) mol/l slightly inhibited agonist-induced contractions in the isolated guinea pig ileum and spontaneous rhythmic contractions in the isolated non-pregnant rat uterus. But loxiglumide had no effect on oxytocin-induced contraction in isolated non-pregnant rat uterus. 3. Cardio-respiratory system: Loxiglumide had no effect on heart rate and electrocardiogram in anesthetized dogs. But it slightly increased blood pressure and decreased the frequency of respirations at a dose of 30 mg/kg, i.v. Furthermore, loxiglumide slightly decreased femoral arterial blood flow at doses of more than 3 mg/kg, i.v. On the other hand, it had no effect on contractile force or contraction rate in the isolated guinea pig atrium and resting tension in the isolated rabbit aorta. 4. Gastrointestinal system: Loxiglumide increased bile secretion at doses of 10 and 30 mg/kg, i.v. in anesthetized rats and at doses of 3, 10 and 30 mg/kg, i.v. in anesthetized dogs. However, total bile acid output was not affected by loxiglumide. On the other hand, loxiglumide had no effect on pancreatic secretion, gastric secretion and gastric emptying in rats and intestinal transport activity in mice. 5. Hematology: In vitro, in the case of samples without bovine serum albumin, at concentrations of more than 1.9 x 10(-3) mol/l loxiglumide showed hemolysis, while in the case of samples with bovine serum albumin, at concentrations of more than 6.9 x 10(-3) mol/l loxiglumide showed hemolysis, and its maximal potency was weak compared to albumin-free conditions. On the other hand, in vivo, loxiglumide had no effect on hemolysis. In addition, it had no effect on platelet aggregation, prothrombin time and activated partial thromboplastin time. 6. Miscellaneous pharmacological actions: Loxiglumide had no effect on local anesthetic activity in guinea pigs and renal function in mice. These results suggest that loxiglumide seems to produce no serious side effects on the central nervous system, autonomic nervous system, cardio-respiratory system, gastrointestinal system, hematological and miscellaneous systems at pharmacologically effective doses. 相似文献
112.
M Shimojima H Ohta A Iwamatsu T Masuda Y Shioi K Takamiya 《Canadian Metallurgical Quarterly》1997,94(1):333-337
Monogalactosyldiacylglycerol (MGDG) synthase (UDPgalactose:1,2-diacylglycerol 3-beta-D-galactosyltransferase; EC 2.4.1.46) catalyzes formation of MGDG, a major structural lipid of chloroplast. We cloned a cDNA for the synthase from cucumber cDNA library. The full-length cDNA clone was 2142 bp, and it contains a 1575-bp open reading frame encoding 525 aa. The open reading frame consists of the regions for a mature protein (422 aa; Mr of 46,552) and transit peptide to chloroplast (103 aa). Although the molecular weight of mature protein region matched that purified from cucumber cotyledons, it was quite different from those purified from spinach (approximately 20 kDa) reported by other groups. The mature region of the protein was expressed in Escherichia coli as a fusion protein with glutathione S-transferase. The expression in E. coli showed that the protein catalyzed MGDG synthesis very efficiently. Therefore, we concluded that the cDNA encodes MGDG synthase in cucumber. In addition, the deduced amino acid sequence of the MGDG synthase cDNA showed homology with MurG of Bacillus subtilis and E. coli, which encode a glycosyltransferase catalyzing the last step of peptidoglycan synthesis in bacteria. This sequence homology implies that the machinery of chloroplast membrane biosynthesis is evolutionarily derived from that of cell wall biosynthesis in bacteria. This is consistent with the endosymbiotic hypothesis of chloroplast formation. 相似文献
113.
N Masuda S Negoro K Takeda N Kurata T Kuwabara S Kobayashi M Fukuoka 《Canadian Metallurgical Quarterly》1998,78(3):388-389
The precise mechanism of fever and flu-like syndrome that occurs in treatment with deoxycytidine analogues remains unclear. This study demonstrated a strong correlation between plasma interleukin 6 levels and fever in treatment with oral (E)-2'-deoxy-2'(fluoromethylene)cytidine, another deoxycytidine analogue. 相似文献
114.
Exfoliative toxins of approximately 30 kDa produced by Staphylococcus hyicus strains NCTC 10350, 1289D-88 and 842A-88 were purified and specific polyclonal antisera were raised against each of the toxins. It was shown by immunoblot analysis and ELISA that three exfoliative toxins from S. hyicus were antigenically distinct. The three toxins were designated ExhA, ExhB and ExhC. From 60 diseased pigs, each representing an outbreak of exudative epidermitis, a total of 584 isolates of S. hyicus were phage typed and tested for production of exfoliative toxin. ExhA-, ExhB- and ExhC-producing S. hyicus isolates were found in 12 (20%), 20 (33%) and 11 (18%), respectively, of the 60 pig herds investigated. Production of the different types of exfoliative toxin was predominantly associated with certain phage groups. However, toxin production was found in all of the six phage groups defined by the phage typing system. Some changes in the distribution of isolates between phage groups were observed when the results of this study were compared to previous investigations. In this study two new antigenically distinct exfoliative toxins were isolated and tools for in vitro detection of toxin producing S. hyicus isolates and for further studies on the exfoliative toxins from S. hyicus have been provided. 相似文献
115.
Kazuo Nakayama Yasunobu Yokomizu Toshiro Matsumura Eiji Kanamori Kazuo Kuwamura 《Electrical Engineering in Japan》2003,144(3):17-27
A power system is a large dynamic system, which includes many nonlinear elements. According to the nonlinear analyses using Hopf bifurcation theory, it can be detected that a limit cycle exists around an operating point, which may affect the global stability of a power system significantly. The authors have presented a numerical method to analyze the nonlinear characteristics in power systems by observing the power swing after some perturbation where the coefficients of nonlinear terms are determined by the least squares method. In this paper the method is modified for the application to a longitudinally interconnected power system including an excitation system, and the influence of the excitation voltage limiter on the nonlinear phenomena of the whole power system can be detected by some numerical analyses. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(3): 17–27, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10193 相似文献
116.
Derived narrow-band auditory brain-stem responses (ABRs) in young normal-hearing subjects revealed a significant gender difference in response time between frequency regions of the cochlea. Females showed shorter delays than males between derived bands. This differential has not been previously reported. As in many early studies, the unmasked amplitude of the wave V complex was significantly larger (30%) in females than males. However, differences in amplitudes of the narrow-band responses were too small to account for the differential in the unmasked response. It is hypothesized that the larger amplitude of the unmasked wave V complex in females occurs because of a faster response time across the cochlea leading to better neural synchrony and, therefore, larger amplitudes. Furthermore, results can be explained by assuming that the stiffness gradient in the cochlea is 13% larger in females than in males. If males and females have the same cochlear tonotopic mapping, the female cochlea should be 13% shorter. This prediction is highly consistent with recent anatomical studies of cochlear length and gender. The results of the present study indicated possibly important cochlear mechanisms that influence the main parameters of ABRs. An understanding of these cochlear mechanisms may improve the diagnostic capabilities of ABRs in patients with peripheral hearing loss. 相似文献
117.
H Masuda S Shichijo M Takeuchi H Imai F Yamashita 《Canadian Metallurgical Quarterly》1976,15(2):186-189
Report of an infant with aplasia of the proximal part of the fibula on both sides; by our knowledge the second observation in the literature. Furthermore the infant shows an aplasia of the thyroidea, a coarctation of the aorta, an atrial septal defect and an intraperitoneally situated ascending as well as descending colon. 相似文献
118.
Masaji Matsuda Chiyoshi Kamizawa Hitoshi Masuda Takashi Nakane Noriaki Sato 《Desalination》1979,29(3):275-284
Taking note of the affinity of some reverse osmosis membranes to Au(CN)-2 in the citrate buffered gold plating rinse, we accomplished the recovery of gold by the adsorption to some polymers. Among several polymers, tested nylon fibre had the most excellent characteristics of adsorption. The amount of adsorption of gold on nylon fiber increased with a decrease in pH value of the solution, and 7.5 mg of gold was adsorbed on 1 g of nylon fiber at pH 3, 25°C. The rate of adsorption increased with an increase in temperature. In the case of desorption, the solution containing cyanide ions at a pH as high as 10 was desirable to be employed as an eluant. By passing the simulated plating rinse through a column of nylon fiber, the adsorption and desorption of gold was successfully accomplished. The maximum concentration of gold in the eluant was approximately 600 ppm. 相似文献
119.
Y Saito T Yamagishi T Nakamura Y Ohyama H Aizawa T Suga Y Matsumura H Masuda M Kurabayashi M Kuro-o Y Nabeshima R Nagai 《Canadian Metallurgical Quarterly》1998,248(2):324-329
Viral respiratory infections cause acute airway abnormalities consisting of inflammation and physiological dysfunction in both animals and humans. It is likely that inflammatory cell products, such as cytokines, contribute substantially to viral-induced airway dysfunction. We hypothesized that imiquimod, an immune response enhancing agent that induces interferon-alpha, would attenuate the development of airway dysfunction during acute viral illness in rats. Adult Brown Norway rats were inoculated with parainfluenza type 1 (Sendai) virus or sterile vehicle, and treated with either imiquimod or water. Respiratory system resistance (Rrs), arterial oxygen tension (Pa,O2), lung viral titres and bronchoalveolar lavage (BAL) leucocyte counts were measured in anaesthetized, paralysed, ventilated rats. Virus-infected, water-treated rats had a significant decrease in Pa,O2 and had significant increases in leucocyte count and Rrs when compared to both the virus-infected, imiquimod-treated, (Pa,O2, p = 0.03; leucocyte count, p = 0.02; and Rrs, p = 0.009) and noninfected, water-treated rats (Pa,O2, p = 0.007; leucocyte count, p = 0.001; and Rrs, p = 0.01). In addition, imiquimod suppressed BAL eosinophils in both virus-infected (p = 0.02) and noninfected (p = 0.001) groups, and lowered overall virus titres (p = 0.03). Thus, both virus-induced airway inflammation and physiological dysfunction were attenuated significantly by imiquimod treatment in this animal model. By further delineating mechanisms by which infections induce airway dysfunction in animal models, more specific pharmacological interventions can be developed for the treatment of virus-induced asthma. 相似文献
120.