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81.
The most methylated phenolic substrate in coal tar creosote, 2,3,5-trimethylphenol (TMP), was mineralized photocatalytically to CO2 and water at pH 3 in illuminated air-equilibrated titania dispersions. Trimethylhydroquinone and trimethylbenzoquinone were the two major aromatic intermediates; trace amounts of trimethylcatechol also formed. Complete mineralization was achieved in oxygenated solutions in ~1 h; conversion of TMP was over in less than ~25 min in aerated solutions and in less than 12 min in oxygenated solutions. 相似文献
82.
We have reported that high glucose conditions (27 mM for 4 days) induces activation of protein tyrosine phosphatases (PTPases) which are associated with impaired insulin signaling in Rat 1 fibroblasts expressing human insulin receptors [Maegawa, H. et al. (1995) J. Biol. Chem. 270, 7724-7730]. In this study, we found increased mRNA-levels of a non-receptor type PTPase, protein tyrosine phosphatase 1B (PTP1B), and receptor type PTPases, leukocyte common antigen-related phosphatase (LAR), and LAR-related phosphatase (LRP), under high glucose conditions. In accordance with these results, LAR content was significantly increased, whereas LRP content was not increased. Cytosolic PTP1B content was increased, but membrane-associated PTP1B content showed no detectable change. Pioglitazone, a thiazolidinedione, normalized increased cytosolic PTPase activity through reduction of cytosolic PTP1B content, but it had no effect on mRNA levels of these PTPases. Under the high glucose condition, we also found that epidermal growth factor (EGF)-stimulated signaling, including tyrosine-phosphorylation of EGF receptor and phosphatidylinositol 3'-kinase activities, was attenuated. Nevertheless, pioglitazone failed to restore the attenuated EGF-signaling. These results indicate that the high glucose conditions cause dysfunction of EGF receptor. However, the increased cytosolic PTP1B content is not involved in the abnormal regulation of EGF-signaling, in contrast to insulin-signaling. 相似文献
83.
Tofani S. Ossola P. d'Amore G. Anglesio L. Kanda M. Novotny D.R. 《Electromagnetic Compatibility, IEEE Transactions on》1996,38(3):341-347
This paper discusses the use of a three-loop antenna system (TLAS) for near-field measurement of electric and magnetic fields from video display terminals (VDTs). We calculated the electric and magnetic dipole moments to derive the electric and magnetic field patterns in the near field region. Electric and magnetic fields, emitted by several different models of VDTs, were evaluated with the TLAS and were compared with those measured by conventional electric and magnetic field probes at different distances and directions from VDTs. A good correlation (±1.6 dB) between the two measurement techniques was found. This agreement is within the accuracy (±2 dB) of the conventional field probe measurements 相似文献
84.
M Shimizu J Ussmüller K Donath K Yoshiura S Ban S Kanda S Ozeki M Shinohara 《Canadian Metallurgical Quarterly》1998,86(5):606-615
BACKGROUND: Patients with asthma show altered surface expression of the adhesion molecules CD11b and L-selectin on airway granulocytes compared with blood granulocytes. OBJECTIVE: To investigate whether this modulation is related to disease activity or due to transendothelial migration, we compared the CD11b and L-selectin expression on blood and induced sputum eosinophils and neutrophils between patients with asthma and normal subjects. METHODS: Eleven normal subjects (21-43 years), nine patients (21-34 years) with mild atopic asthma and 10 patients (20-47 years) with moderate to severe atopic asthma on regular treatment with inhaled steroids underwent sputum induction by inhalation of nebulized hypertonic saline (4.5%). CD11b and L-selectin expression on granulocytes from blood and DTT-homogenized sputum were analysed by flow cytometry. Eosinophils could be discriminated from neutrophils by using depolarized light scatter. Disease activity was assessed by baseline FEV1 and airway responsiveness to histamine (PC20). RESULTS: Sputum eosinophils showed higher expression of CD11b (P<0.001) and lower expression of L-selectin (P<0.001) compared with peripheral blood eosinophils. CD11b and L-selectin expression on eosinophils from blood or sputum did not differ between the three groups. Similar results were obtained for neutrophils. The PC20 in the patients with moderate-to-severe asthma was related to CD11b expression on blood (R=-0.92, P=0.001) and sputum eosinophils (R=0.75, P=0.02). CONCLUSIONS: Flow cytometry of induced sputum granulocytes from asthmatic as well as normal subjects is feasible. We conclude that the modulated expression of CD11b and L-selectin on airway granulocytes is not specific for asthmatic airway inflammation, but is probably the result of tissue migration per sé. This implies that CD11b and L-selectin expression on granulocytes in induced sputum cannot be used as marker of disease activity. 相似文献
85.
Genetic algorithms for flowshop scheduling problems 总被引:11,自引:0,他引:11
Tadahiko Murata Hisao Ishibuchi Hideo Tanaka 《Computers & Industrial Engineering》1996,30(4):1061-1071
In this paper, we apply a genetic algorithm to flowshop scheduling problems and examine two hybridizations of the genetic algorithm with other search algorithms. First we examine various genetic operators to design a genetic algorithm for the flowshop scheduling problem with an objective of minimizing the makespan. By computer simulations, we show that the two-point crossover and the shift change mutation are effective for this problem. Next we compare the genetic algorithm with other search algorithms such as local search, taboo search and simulated annealing. Computer simulations show that the genetic algorithm is a bit inferior to the others. In order to improve the performance of the genetic algorithm, we examine the hybridization of the genetic algorithms. We show two hybrid genetic algorithms: genetic local search and genetic simulated annealing. Their high performance is demonstrated by computer simulations. 相似文献
86.
DeLyser R.R. Holloway C.L. Johnk R.T. Ondrejka A.R. Kanda M. 《Electromagnetic Compatibility, IEEE Transactions on》1996,38(4):576-584
Return loss as a function of frequency and angle of incidence is studied to determine the effectiveness of the absorbing material used in an anechoic chamber. This alone is not enough to determine a figure of merit for an anechoic chamber or to compare the figure of merit for one anechoic chamber to that of another. While the information gained from return loss calculations and measurements as a function of angle of incidence is valuable, an overall measure of anechoic chamber effectiveness is necessary in order to compare different designs. In this paper, a new chamber figure of merit which is based on the decay time of the chamber is introduced. This decay time is, in turn, based on the average power absorbed by the chamber walls. The resulting model is simple and does not require intensive numerical computation. Calculations of the figure of merit for anechoic chambers which contain different types of absorbing materials are shown, and calculated and measured values of decay time for a primary standards calibrations facility are compared 相似文献
87.
We have reported previously that cathodoluminescence (CL) spectra of type II diamond change with irradiation of 20 kV electron beam using a scanning electron microscope (SEM), although it is known that diamond has high resistance against radiation beams. Following the previous paper, the diamond irradiated with the electron beam was annealed at 500 °C, and the CL spectra were measured. It was found from the annealed sample that the CL spectra which changed with the irradiation are partially recovered, namely, the lines at 420 nm and 540 nm formed with the irradiation are annealed out, and the lines at 485 nm, 535 nm and 545 nm which disappeared with the irradiation are recovered. However the 420 nm broad band that appeared with the irradiation does not change with the heat treatment. The effect of the heat treatment suggests that the CL peaks which changed with the irradiation are related to ionization of defects. 相似文献
88.
To develop a less reactogenic but equally immunogenic vaccine, this study of 91 human volunteers compared the safety and immunogenic potency of a new, cell culture-derived vaccinia virus vaccine administered intradermally and intramuscularly with the licensed vaccinia vaccine administered by scarification. Cutaneous pox lesions developed in a higher proportion of scarification vaccinees. Scarification and intradermal vaccine recipients who developed cutaneous pox lesions had more local reactions but also achieved significantly higher cell-mediated and neutralizing antibody responses than those who did not develop pox lesions. Although less reactogenic, intradermal or intramuscular administration of vaccinia vaccine without the concomitant development of a cutaneous pox lesion induced lower immune responses. 相似文献
89.
A Kinoshita M Nakano N Suyama H Takatani T Kanda S Fujimoto M Oka S Kohno 《Canadian Metallurgical Quarterly》1997,36(11):815-818
Hemorrhagic adrenal metastasis from lung cancer is extremely rare, although adrenal involvement is common in widely disseminated cancer. We report a case of massive adrenal hemorrhage secondary to metastasis of lung cancer. A 47-year-old female was treated by left upper lobectomy and mediastinal lymph node resection for an adenocarcinoma with intrapulmonary metastasis in the left upper lobe. Eight months later, she presented with right flank and back pain, and abdominal ultrasonography and computed tomography showed a right solitary adrenal tumor with massive hemorrhage. The tumor was not resectable and partially responded to chemotherapy. A massive adrenal hemorrhage, secondary to metastasis of lung cancer, presents with nonspecific clinical signs and symptoms. In lung cancer patients with an acute flank or back pain, hemorrhagic adrenal metastasis should be considered in the differential diagnosis. 相似文献
90.
T Sawada M Ohmichi K Koike Y Kanda A Kimura K Masuhara H Ikegami M Inoue A Miyake Y Murata 《Canadian Metallurgical Quarterly》1997,138(12):5275-5281
The GT1-1 GnRH neuronal cell lines exhibit highly differentiated properties of GnRH neurons. We have used GT1-1 cells to study the roles of norepinephrine (NE), membrane depolarization, calcium influx, and phorbol esters in the regulation of mitogen-activated protein (MAP) kinase. NE, which is known to stimulate the release of GnRH, induced MAP kinase activity, the tyrosine phosphorylation of MAP kinase, and MAP kinase kinase activity. Forskolin led to activation of MAP kinase comparable with that induced by NE, and a selective inhibitor of cAMP-dependent protein kinase, H8, attenuated the NE-induced activation of MAP kinase. On the other hand, elimination of extracellular calcium by EGTA completely blocked NE-induced tyrosine phosphorylation of MAP kinase, and a selective inhibitor of calcium/calmodulin-dependent protein kinase, KN-62, attenuated the NE-induced activation of MAP kinase. Furthermore, depolarization of GT1-1 cells with 75 mM KCl, 10 microM BayK 8644, or 1 microM calcium ionophore (A23187) induced rapid tyrosine phosphorylation of MAP kinase. The omission of calcium from the extracellular medium completely abolished these effects of tyrosine phosphorylation of MAP kinase. Phorbol 12-myristate 13-acetate (PMA) also induced MAP kinase activity, but pretreatment of the cultured cells with PMA to down-regulate protein kinase C did not abolish the activation of MAP kinase by NE. In addition, although phosphorylation of Raf-1 kinase was stimulated by PMA, this phosphorylation was not induced by either NE or A23187. These results demonstrate that NE activates MAP kinase directly in GT1-1 cells, and that the effect of NE is mediated by increase in the cAMP level and by calcium influx, but not by PMA-sensitive protein kinase C or Raf-1 kinase. 相似文献