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951.
952.
The effect of visible light on carotenoid content in the dermatophyte Trichophyton mentagrophytes ATCC 26323 was investigated. The fungus T. mentagrophytes accumulated several carotenoids when arthroconidiated on Sabouraud glucose agar at 37°C. When this fungus was irradiated with moderate fluence rates of white light, the resultant arthroconidia contained considerably less carotenoids in comparison with dark controls although growth and arthroconidiation of this fungus were not at all affected by visible light. The reduction of carotenoid content in arthroconidia was due primarily to blue light, although red light caused a slight decrease in pigmentation. The suppressive effect of visible light on pigmentation was fluence rate dependent. Carotenoid accumulation in arthroconidia was inversely and exponentially related to the fluence rate of light. Carotenoid formation in arthroconidiating T. mentagrophytes was neither photoinducible nor photostimulative. An analysis of isolated carotenoids revealed that visible light caused a quantitative reduction in pigmentation, and no single carotenoid was selectively decreased.Non-standard abbreviations PI
pigmentation index
-
r
coefficient of correlation 相似文献
953.
The activity of topoisomerase I in nuclear extracts increased about three-fold 5 min after gamma-irradiation (840-2500 rads) of human peripheral blood lymphocytes or cultured lymphoblastoid cells. The change may reflect modification of the enzyme by nuclear ADP-ribosyl transferase, which is known to be activated by DNA breaks. 相似文献
954.
955.
Steven W. Kortum Rhonda M. Lachance Barbara A. Schweitzer Gopichand Yalamanchili Hayat Rahman Michael D. Ennis Rita M. Huff Ruth E. TenBrink 《Bioorganic & medicinal chemistry letters》2009,19(20):5919-5923
Herein we describe the design and synthesis of a novel series of potent thienopyrimidine P2Y12 inhibitors and the negative impact protein binding has on the inhibition of platelet aggregation. 相似文献
956.
Under appropriate experimental conditions, phytochrome controls leaflet closure in Albizzia by regulating differential turgor changes in motor cells of the pulvinule. Closure occurs when subepidermal dorsal cells expand and ventral cells become compressed; reopening involves the reverse changes. The internal cells surrounding the vascular core remain relatively unchanged during leaflet movement. Fine structural studies revealed several unusual features of the motor cells including: (1) fibrils oriented parallel to one another in the cytoplasmic matrix; (2) numerous spherosomes that appear to coalesce and enlarge to form vacuoles; and (3) a multivacuolate condition. 相似文献
957.
958.
959.
960.
Seetharamaiyer Padmanabhan Ruth C. Lavin Paresh M. Thakker Jinqing Guo Lu Zhang Deke Moore Michael E. Perlman Cassandra Kirk Deborah Daly Kathy J. Burke-Howie Teresa Wolcott Suchitra Chari David Berlove James B. Fischer William F. Holt Graham J. Durant Robert N. McBurney 《Bioorganic & medicinal chemistry letters》2001,11(24):1945-3155
Solution-phase synthesis of various acylguanidine derivatives and the evaluation of a small library of compounds as potential sodium channel blockers are described. 相似文献