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11.
We have investigated the effect of methylprednisolone on the intracellular activity of erythromycin and clindamycin in vitro. An assay system was developed for the determination of intracellular activity of antibiotics against Legionella pneumophila using guinea pig resident alveolar macrophages. Erythromycin at a concentration of 0.625 mg/L (5 x MIC) and clindamycin at a concentration of 8 mg/L (MIC) inhibited the growth of a single strain of L. pneumophila in macrophages, whilst ceftizoxime at a concentration of 0.625 mg/L (5 x MIC) did not. Methylprednisolone at therapeutic concentrations did not affect the intracellular antibacterial activity of either erythromycin or clindamycin against L. pneumophila. We found no direct effect of methylprednisolone on the intracellular antibacterial activity of either erythromycin or clindamycin. 相似文献
12.
F Higa N Kusano M Tateyama T Shinzato N Arakaki K Kawakami A Saito 《Canadian Metallurgical Quarterly》1998,36(5):1392-1398
We developed a new simple assay for the quantitation of the activities of drugs against intracellular Legionella pneumophila. The cells of a murine macrophage-like cell line (J774.1 cells) allowed the intracellular growth and replication of the bacteria, which ultimately resulted in cell death. The infected J774.1 cell monolayers in 96-well microplates were first treated with antibiotics and were further cultured for 72 h. The number of viable J774.1 cells in each well was quantified by a colorimetric assay with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and an enzyme-linked immunosorbent assay reader. The number of growing bacteria in each well was also determined by counting the numbers of CFU on buffered charcoal yeast extract-alpha agar plates. Viable J774.1 cell counts, determined by the colorimetric assay, were inversely proportional to the number of intracellular replicating bacteria. The minimum extracellular concentrations (MIECs) of 24 antibiotics causing inhibition of intracellular growth of L. pneumophila were determined by the colorimetric assay system. The MIECs of beta-lactams and aminoglycosides were markedly higher than the MICs in buffered yeast extract-alpha broth. The MIECs of macrolides, fluoroquinolones, rifampin, and minocycline were similar to the respective MICs. According to their intracellular activities, clarithromycin and sparfloxacin were the most potent among the macrolides or fluoroquinolones tested in this study. Our results indicated that the MTT assay system allows comparative and quantitative evaluations of the intracellular activities of antibiotics and efficient processing of a large number of samples. 相似文献
13.
A Nakamura S Tanaka H Takayama M Sakamoto H Ishii M Kusano Y Onizuka S Ota K Mitamura 《Canadian Metallurgical Quarterly》1998,37(10):884-890
A 77-year-old female was admitted to our hospital because of pyrexia and a right retroperitoneal mass. Leukocytosis and other inflammatory findings were noted. Bone-marrow aspiration revealed hypercellularity with no malignant cells. An additional mass was detected sonographically in the pelvis. The serum concentration of granulocyte colony-stimulating factor (G-CSF) was highly elevated (299 pg/ml). The tumors were removed at laparotomy, and the pelvic mass was found to arise from the ileocecal mesentery. Postoperatively, white blood cell count and serum G-CSF concentrations decreased to normal levels. The mesenteric tumor showed weakly positive immunostaining for human G-CSF, and Northern and polymerase chain reaction (PCR) analyses detected CSF and its mRNA in the mesenteric tumor. 相似文献
14.
The kinetic parameters of the first stage of polystyrene degradation have been investigated to elucidate the reaction mechanisms using the flow reactor system. The decrease in molecular weight of polystyrene was recorded at minute intervals over the temperature range 310°–390°C. Generally, the first and second stages were observed by thermogravimetric analysis (t.g.a.), however in the early stage of the degradation volatile yields of at least 5% occurred. Therefore, using t.g.a. analysis it is difficult to detect this earlier stage. It became evident that the first stage in the earlier part of the reaction could be detected by g.p.c. analysis. We have observed the hidden kinetic parameters of the nature of the first stage of the polystyrene degradation. The results indicate that the main chains were degraded randomly with the small quantitative volatile groups in the first stage and the rates of decrease in molecular weight in the first stage against reaction temperatures were evaluated as log ks = 12.0 ? 41300/RT. 相似文献
15.
Arachidonic acid hydroperoxide (15-hydroperoxyeicosatetraenoic acid; 15-HPETE) was introduced into human parotid saliva and
incubated at 37°C. Straight phase high-performance liquid chromatography analysis of the reaction mixture showed that 15-HPETE
was detoxified to its reduced form, 15-hydroxyeicosatetraenoic acid, in the presence of glutathione. Therefore, it is concluded
that human parotid saliva possesses fatty acid hydroperoxide-reducing ability. However, its effectiveness was found to be
lower than that of blood plasma. 相似文献
16.
At temperature above 300°C the glycosyl units of cellulose are simultaneously depolymerized to a tar and decomposed to a char by evolution of H2O, CO, and CO2. When the glycosyl units are depleted, a stable char is formed containing about 30% aliphatic and 70% aromatic components. The aliphatic component is formed first, but on further heating is converted to polycyclic aromatic structures. The chars formed at lower temperatures are more combustible because the aliphatic component of the char is highly pyrophoric and is oxidized almost at the same temperature at which it is formed (~360°C). The aromatic component, however, is less reactive and is oxidized at ~520°C. Consequently, the chars formed at higher temperatures are less combustible. It has been shown that (NH4)2HPO4, which is a well-known flame retardant and smoldering inhibitor, lowers the pyrolysis temperature and increases the char yield by accelerating the decomposition reactions. This affects the composition of the intermediate chars but the final products have about the same composition irrespective of additives. (NH4)2HPO4 also lowers the rate of oxidation of the aromatic component and the corresponding heat release. NaCl, which is an enhancer of smoldering combustion, has a slight stabilizing effect on pyrolysis of cellulose. It lowers the oxidation temperature of the aromatic component and dramatically increases its rate. The corresponding heat release is also increased due to complete oxidation to CO2. The rate of oxidation calculated from the dynamic thermal analysis data is more than tripled by NaCl and significantly reduced by (NH4)2HPO4. 相似文献
17.
Yasuhiro Jimbo Yuki Tamatsukuri Minato Ito Kohei Yokoyama Yoshiharu Hirakata Shunpei Yamazaki 《Journal of the Society for Information Display》2015,23(7):313-318
To improve the reliability and mechanical durability of a flexible organic light‐emitting diode display, the entire flexible display is coated with an aluminum oxide film by atomic layer deposition (ALD). Because the step coverage of ALD is excellent, the AlOx film was deposited not only on the front and back surfaces but also on the side surfaces of the display. A high‐temperature and high‐humidity preservation test, repetitive bending tests, and a pencil hardness test were conducted on the flexible display with ALD‐AlOx coating. The display survived 500 h of a 65°C, 95% preservation test, endured a 100,000‐time repetitive bending test with a curvature radius of 4 mm, and was found to have a pencil hardness of 4H. 相似文献
18.
Computational Visual Media - Iris folding is an art-form consisting of layered strips of paper, forming a spiral pattern behind an aperture, which can be used to make cards and gift tags. This... 相似文献
19.
Yuki Takenaka Norihiro Abe Yoshihiro Tabuchi Hirokazu Taki Shoujie He 《Artificial Life and Robotics》2009,14(2):224-227
This research was aimed at making a robot that can go and get an object designated by the user. We produced a robot control
system that uses pointing and voice control. This control system is composed of two systems. One system is the object instruction
system that uses pointing, and the other is the object instruction system that uses voice. The approximate position of a designated
object is recognized by the object instruction system that uses pointing, and information about the object and instructions
about the operation are conveyed by the object instruction system that uses voice. This time, the object instruction system
that uses pointing has been designed and verified as the first step. A calculation resource to calculate the approximate position
of the designated object is obtained when the user points directly at the object. A robot can be moved around a designated
object by using this system. The object instruction system that uses voice will be constructed in future work. 相似文献
20.
Yuki Akinaga Tokuhisa Kawawaki Hinano Kameko Yuki Yamazaki Kenji Yamazaki Yuhi Nakayasu Kosaku Kato Yuto Tanaka Adie Tri Hanindriyo Makito Takagi Tomomi Shimazaki Masanori Tachikawa Akira Yamakata Yuichi Negishi 《Advanced functional materials》2023,33(33):2303321
Single-atom (SA) catalysts exhibit high activity in various reactions because there are no inactive internal atoms. Accordingly, SA cocatalysts are also an active research fields regarding photocatalytic hydrogen (H2) evolution which can be generated by abundant water and sunlight. Herein, it is investigated whether 10 transition metal elements can work as an SA on graphitic carbon nitride (g-C3N4; i.e., gCN), a promising visible-light-driven photocatalyst. A method is established to prepare SA-loaded gCN at high loadings (weight of ≈3 wt.% for Cu, Ni, Pd, Pt, Rh, and Ru) by modulating the photoreduction power. Regarding Au and Ag, SAs are formed with difficulty without aggregation because of the low binding energy between gCN and the SA. An evaluation of the photocatalytic H2-evolution activity of the prepared metal SA-loaded gCN reveals that Pd, Pt, and Rh SA-loaded gCN exhibits relatively high H2-evolution efficiency per SA. Transient absorption spectroscopy and electrochemical measurements reveal the following: i) Pd SA-loaded gCN exhibits a particularly suitable electronic structure for proton adsorption and ii) therefore they exhibit the highest H2-evolution efficiency per SA than other metal SA-loaded gCN. Finally, the 8.6 times higher H2-evolution rate per active site of Pd SA is achieved than that of Pd-nanoparticles cocatalyst. 相似文献