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排序方式: 共有463条查询结果,搜索用时 171 毫秒
41.
Kumar Samir Taneichi Taiga Fukuoka Takao Namura Kyoko Suzuki Motofumi 《Cellulose (London, England)》2021,28(17):10803-10813
Cellulose - Surface-enhanced Raman spectroscopy (SERS)-based biosensors have recently been extensively developed because of their high sensitivity and nondestructive nature. Conventional SERS... 相似文献
42.
Yukiko Yasuoka Yuichiro Izumi Takashi Fukuyama Haruki Omiya Truyen D. Pham Hideki Inoue Tomomi Oshima Taiga Yamazaki Takayuki Uematsu Noritada Kobayashi Yoshitaka Shimada Yasushi Nagaba Tetsuro Yamashita Masashi Mukoyama Yuichi Sato Susan M. Wall Jeff M. Sands Noriko Takahashi Katsumasa Kawahara Hiroshi Nonoguchi 《Molecules (Basel, Switzerland)》2022,27(3)
Anemia is a major complication of chronic renal failure. To treat this anemia, prolylhydroxylase domain enzyme (PHD) inhibitors as well as erythropoiesis-stimulating agents (ESAs) have been used. Although PHD inhibitors rapidly stimulate erythropoietin (Epo) production, the precise sites of Epo production following the administration of these drugs have not been identified. We developed a novel method for the detection of the Epo protein that employs deglycosylation-coupled Western blotting. With protein deglycosylation, tissue Epo contents can be quantified over an extremely wide range. Using this method, we examined the effects of the PHD inhibitor, Roxadustat (ROX), and severe hypoxia on Epo production in various tissues in rats. We observed that ROX increased Epo mRNA expression in both the kidneys and liver. However, Epo protein was detected in the kidneys but not in the liver. Epo protein was also detected in the salivary glands, spleen, epididymis and ovaries. However, both PHD inhibitors (ROX) and severe hypoxia increased the Epo protein abundance only in the kidneys. These data show that, while Epo is produced in many tissues, PHD inhibitors as well as severe hypoxia regulate Epo production only in the kidneys. 相似文献
43.
Shusuke Yamanaka Keita Kanda Toru Saito Yasutaka Kitagawa Takashi Kawakami Masahiro Ehara Mitsutaka Okumura Haruki Nakamura Kizashi Yamaguchi 《Chemical physics letters》2012
We assessed the applicability and basis set dependency of the B3LYP functional to investigate magnetic interactions of Mn complexes. For the purpose, we constructed a test set consisting of 16 Mn complexes with various oxidation states and structural motifs.The B3LYP results correctly reproduced magnetism and magneto–redox correlation of the standard μ-oxo motifs with superexchange paths, while it does not work for weak magnetic complexes. We also showed that a modest basis set yields results similar to those of triple-zeta plus diffuse-and-polarization functions. This basis set is expected to be a standard basis set for investigating magnetism of manganese complexes. 相似文献
44.
We calculate scattering functions S(q-->,omega) of neutron Compton scattering (NCS) for a proton (deuteron) pair in the entangled state caused by the indistinguishability of particles. From the calculation, it is concluded that the effect of entanglement on the scattering intensity is undetectable in NCS experiments because of their high energy transfer and broad energy resolution. 相似文献
45.
46.
Oka H Ito Y Ikai Y Matsumoto H Kato K Yamamoto I Shimizu M Kawamura N Miyazaki Y Nojiri T Okumura M Ohmi S Sato T Mori G 《Journal of AOAC International》2001,84(2):350-353
A survey was conducted to determine the incidence of tetracycline antibiotic (TCAs) residues in the kidneys of slaughtered animals that did not pass inspection for human consumption by the Japanese Food Sanitation Law and the Meat Inspection Law at the slaughterhouses in Aichi Prefecture, Japan, from April 1985 to March 1998. The kidneys were analyzed by the AOAC Official Method 995.09. Among 424 animals (147 cattle and 277 pigs), 131 (30.9%) were contaminated with TCAs, including 69 (16.3%) with chlortetracycline (CTC), 61 (14.4%) with oxytetracycline (OTC), 3 (0.7%) with tetracycline (TC), and 1 (0.2%) with doxycycline (DC). One sample (cattle kidney) was contaminated with both OTC and DC. The frequencies of OTC and TC residues were significantly higher (p < 0.05) in cattle than in pigs, whereas, the frequency of CTC was significantly higher (p < 0.01) in pigs. Pig kidney samples collected in 1991-1997 had significantly higher incidences of TCAs and CTC (p < 0.01) residues than those in 1985-1986. 相似文献
47.
A. Ueda H. Ohta S. Okubo Z. Hiroi M. Okumura M. Takano 《Applied magnetic resonance》2000,19(3-4):399-402
Quasi-one-dimensional (1-D) cupric oxide Ca1?xCuO2 (x = 0.164) is the system with 25–40% hole-doped edge-sharing CuO2 chains. However, the holes are almost localized in Ca1?xCuO2 and its magnetic susceptibility with a peak at 30 K was explained by the model considering both 1-D antiferromagnetic chains and spin dimers (Z. Hiroi, M. Okumura, Y. Nabeshima, T. Yamada, M. Takano: J. Phys. Soc. Jpn.69, 1824, 2000). To clarify the magnetic nature of Ca1?xCuO2, we performed submillimeter-wave electron spin resonance (ESR) measurements on a powder sample of Ca0.83?6CuO2. The resonance above 12 K showed typical powder ESR of Cu2+ and theg-values were determined to be g∥= 2.33 and g⊥ = 2.06 from the analysis. The resonance below 12 K changed completely from ESR. The frequency-field relation of ESR at 1.8 K clearly showed the easy-axis type antiferromagnetic resonance. 相似文献
48.
The electrophoretic detection of two kinds of p-quinone anion radicals arising from the electrolysis of benzoquinone and chloranil was achieved by employing an acetonitrile medium. Sufficient dehydration of a running solution was necessary for the detection of the benzoquinone anion radical. Oxygen in the running solution also caused a serious decrease in the amount of the benzoquinone anion radical during electrophoresis. The addition of methanol as a hydrogen-donor decreased the electrophoretic mobility of the benzoquinone anion radical significantly, while that of the chloranil anion radical was little changed. This result is interpreted in terms of hydrogen-bonding interaction between the p-quinone anion radicals and methanol, reflecting the magnitude of their proton-accepting ability (benzoquinone anion radical > chloranil anion radical). 相似文献
49.
Hideya Kawasaki Naoyuki Takahashi Hiroki Fujimori Kouji Okumura Takehiro Watanabe Chisato Matsumura Syusuke Takemine Takeshi Nakano Ryuichi Arakawa 《Rapid communications in mass spectrometry : RCM》2009,23(20):3323-3332
The pyrolytic highly oriented graphite polymer film (PGS) was first employed to analyze low‐mass analytes in environmental analysis by surface‐assisted laser desorption/ionization mass spectrometry (SALDI‐MS). PGS is a synthetic uniform and highly oriented graphite polymer film with high thermal anisotropic conductivity. We have found that negative ion mode SALDI‐MS using oxidized PGS (PGS‐SALDI‐MS) can be used to detect [M–H]? ions from perfluorooctanoic acid (PFOA) and other perfluoroalkylcarboxylic acids when the PGS surface is modified with the cationic polymer polyethyleneimine (PEI). The signal intensity of PFOA when employing the PEI modification showed a ten‐fold increase over that obtained from desorption/ionization on porous silicon (DIOS). PFOA was quantified using PGS‐SALDI‐MS and the calibration curve showed a wide linear dynamic range of response (20–1000 ppb). The combination of atmospheric pressure ionization and PGS (AP‐PGS‐SALDI) showed greater signal intensity than vacuum PGS‐SALDI for deprotonated PFOA. Several other environmentally important chemicals, including perfluoroalkylsulfonic acid, pentachlorophenol, bisphenol A, 4‐hydroxy‐2‐chlorobiphenyl, and benzo[a]pyrene, were also successfully used to evaluate PGS‐SALDI‐MS. In addition, we found that nonafluoro‐1‐butanesulfonic acid was able to produce protonated peptides in positive ion PGS‐SALDI‐MS, but that perfluoropentanoic acid and trifluoroacetic acid were not. It is suggested that perfluoroalkylsulfonic acids are better protonating agents than perfluoroalkylcarboxylic acids in SALDI‐MS. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
50.
An acetylcholine sensor was constructed with acetylcholinesterase which was immobilized on a hydrogen ion-selective coated-wire electrode and fundamental properties of this sensor were investigated. Acetylcholine could be determined in the range 0.1–10 rum with response times of 3–10 min. The effects of pH and concentration of buffer solution on the determination and fluctuations in the data obtained with this sensor were also investigated. Possibilities for the practical use of this acetylcholine micro-sensor are suggested. 相似文献