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31.
Hypsorhodopsin was formed in frog retina by irradiation at liquid helium temperature and converted into bathorhodopsin above about 29 K. 相似文献
32.
Takumi Yoshizawa Nobuichi Morooka Yuzuru Sawada Shun-Ichi Udagawa 《Applied microbiology》1976,32(3):441-442
A tremorgenic mycotoxin was isolated from Penicillium paraherquei Abe ex G. Smith and identified as verruculogen. It was produced at the rate of approximately 1 mg/g of the dried fungal mycelium cultured on peptone-enriched Czapek-Dox medium at 28°C. 相似文献
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Satoh T Fujita KI Munakata H Itoh S Nakamura K Kamataki T Itoh S Yoshizawa I 《Analytical biochemistry》2000,286(2):179-186
To establish a prediction system for drug-induced gynecomastia in clinical fields, a model reaction system was developed to explain numerically this side effect. The principle is based on the assumption that 50% inhibition concentration (IC(50)) of drugs on the in vitro metabolism of estradiol (E2) to its major product 2-hydroxyestradiol (2-OH-E2) can be regarded as the index for achieving this purpose. By using human cytochrome P450s coexpressed with human NADPH-cytochrome P450 reductase in Escherichia coli as the enzyme, the reaction was examined. Among the nine enzymes (CYP1A1, 1A2, 2A6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4) tested, CYP3A4 having a V(max)/K(m) (ml/min/nmol P450) value of 0.32 for production of 2-OH-E2 was shown to be the most suitable enzyme as the reagent. The inhibitory effects of ketoconazole, cyclosporin A, and cimetidine toward the 2-hydroxylation of E2 catalyzed by CYP3A4 were obtained, and their IC(50) values were 7 nM, 64 nM, and 290 microM, respectively. The present results suggest that IC(50) values thus obtained can be substituted as the prediction index for gynecomastia induced by drugs, considering the patients' individual information. 相似文献
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Takuya Tsunoda Hiroshi Tanimura Hiroki Yamaue Makoto Iwahashi Masaji Tani Mikoko Tamai Kazuo Arii Kohei Noguchi 《Biotherapy》1992,4(1):9-15
In adoptive immunotherapy, the number of effector cells is one of the major factors relating to the therapeutic efficacy. We demonstrated that tumor-infiltrating lymphocytes (TILs) were stimulated to proliferate by incubation with interleukin 2 (IL-2) plus interleukin 4 (IL-4). TILs cultured with IL-2 plus IL-4 increased 3.1-fold more than TILs cultured with IL-2 alone. However, IL-4 did not alter the cytotoxic activity of TILs against autologous tumor cells and established tumor cell lines. It is suggested that IL-2 receptor is related to the mechanism of the proliferation of activated TILs cultured by combination with IL-2 and IL-4. Thus, the combination of IL-2 and IL-4 may increase the efficacy of adoptive immunotherapy using activated TILs. 相似文献
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Solvent polarity effects on supramolecular chirality of a polyfluorene‐thiophene copolymer 下载免费PDF全文
Takashi Hirahara Masahiro Yoshizawa‐Fujita Yuko Takeoka Masahiro Rikukawa 《Chirality》2018,30(6):699-707
This study demonstrates the supramolecular chirality control of a conjugated polymer via solvent polarity. We designed and synthesized a chiral polyfluorene‐thiophene copolymer having two different chiral side chains at the 9‐position of the fluorene unit. Chiral cyclic and alkyl ethers with different polarities were selected as the chiral side chains. The sign of the circular dichroism spectra in the visible wavelength region was affected by the solvent system, resulting from the change of supramolecular structure. The estimation of the solubility parameter revealed that the solubility difference of the side chains contributed to the change of the circular dichroism sign, which was also observed in spin‐coated films prepared from good solvents having different polarities. 相似文献
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T Saitoh J Komano Y Saitoh T Misawa M Takahama T Kozaki T Uehata H Iwasaki H Omori S Yamaoka N Yamamoto S Akira 《Cell host & microbe》2012,12(1):109-116
Neutrophils contribute to pathogen clearance by producing neutrophil extracellular traps (NETs), which are genomic DNA-based net-like structures that capture bacteria and fungi. Although NETs also express antiviral factors, such as myeloperoxidase and α-defensin, the involvement of NETs in antiviral responses remains unclear. We show that NETs capture human immunodeficiency virus (HIV)-1 and promote HIV-1 elimination through myeloperoxidase and α-defensin. Neutrophils detect HIV-1 by Toll-like receptors (TLRs) TLR7 and TLR8, which recognize viral nucleic acids. Engagement of TLR7 and TLR8 induces the generation of reactive oxygen species that trigger NET formation, leading to NET-dependent HIV-1 elimination. However, HIV-1 counteracts this response by inducing C-type lectin CD209-dependent production of interleukin (IL)-10 by dendritic cells to inhibit NET formation. IL-10 suppresses the reactive oxygen species-dependent generation of NETs induced upon TLR7 and TLR8 engagement, resulting in disrupted NET-dependent HIV-1 elimination. Therefore, NET formation is an antiviral response that is counteracted by HIV-1. 相似文献