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971.
4-Phenyl-1,2,3,6-tetrahydropyridine, an excellent fragment to improve the potency of PARP-1 inhibitors 总被引:1,自引:0,他引:1
Ishida J Hattori K Yamamoto H Iwashita A Mihara K Matsuoka N 《Bioorganic & medicinal chemistry letters》2005,15(19):4221-4225
We have shown that a 4-phenyl-1,2,3,6-tetrahydropyridine fragment plays an important role in improving inhibitory potency against poly(ADP-ribose) polymerase-1 (PARP-1). Various benzamide analogues linked with this fragment via alkyl spacers have been prepared and evaluated. As a result, some of them have been found to be highly potent PARP-1 inhibitors. 相似文献
972.
Ishida T 《化学与生物多样性》2005,2(5):569-590
This review article summarizes our knowledge of the metabolism of mono- and sesquiterpenoids in mammals, microorganisms, cloned-insect enzymes, and plant-cultured cells. A number of unusual enzymatic reactions and products are reported such as the stereoselective formation of primary alcohols from sterically congested Me2C groups. Such enzymatic processes, including unknown chemical transformations under abiotic conditions, could lead to the discovery of new chemical reactions and might be helpful in the design of new drugs. The transformations of the following mono- and sesquiterpenoids (in alphabetical order) are discussed: (+)-(1R)-aromadendrene (61), (-)-allo-aromadendrene (62), (+/-)-camphene (21), (-)-cis-carane (20), (+)-3-carene (17), (+/-)-carvone (27), (-)-beta-caryophyllene (43), (+)-cedrol (35), cuminaldehyde (25), (+)-curdione (69), (-)-cyclocolorenone (60), (-)-elemol (51), (2E,6E)-farnesol (31), germacrone (67), ginsenol (40), (-)-globulol (63), isoprobotryan-9alpha-ol (82a), juvenile hormone III (33), (+)-ledol (65), (+)-longifolene (46), myrcene (3), (-)-myrtenal (23), (+)-nootkatone (48), patchouli alcohol (37), (-)-perillaldehyde (24), (-)-alpha- and beta-pinene (8 and 9), alpha-santalol (28), (-)-6beta-santonin (83a), 6beta-tetrahydrosantonin (83b), beta-selinene (57), alpha-thujone (26a), beta-thujone (26b), T-2 toxin (87), and valerianol (53). 相似文献
973.
974.
Generative Cell Specification Requires Transcription Factors Evolutionarily Conserved in Land Plants
975.
Atsuko Takeuchi Yuki Ishida Hiroko Sekimoto Sonoko Masuda Toshio Okano Soroku Nishiyama Ichiro Matsuda Tadashi Kobayashi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,691(2):1987
A simplified method for the determination of 25-hydroxy and 1α,25-dihydroxy metabolites of vitamins D2 and D3 in human plasma was developed. Plasma samples were deproteinizated and applied to a Bond Elut C18 OH cartridge to separate 25-hydroxyvitamin D (25-OH-D) and 1α-25-dihydroxyvitamin D [1,25(OH)2D] fractions. The 25-OH-D fraction was purified by a Bond Elut C18 cartridge and 25-OH-D2 and 25-OH-D3 were assayed by HPLC using a Zorbax SIL column. The 1,25(OH)2D fraction obtained above was subsequently applied to HPLC using a Zorbax SIL column to separate 1,25(OH)2D2 and 1,25(OH)2D3 fractions which were determined by a radioreceptor assay (RRA) using calf thymus receptor. The method was applied to nutritional studies. 相似文献
976.
977.
978.
A new species of chlorarachniophyte alga, Lotharella vacuolata Ota et Ishida sp. nov., is described. This alga has been maintained as strain CCMP240 at the Provasoli‐Guillard National Center for Culture of Marine Phytoplankton at Bigelow Laboratory for Ocean Sciences. We examined in detail its morphology, ultrastructure and life cycle, using light microscopy, transmission electron microscopy and time‐lapse videomicroscopy. The dominant stage in the life cycle was represented by coccoid cells; however, amoeboid and flagellated stages were also observed. This alga showed unique post‐cell division behavior: one of the two daughter cells became amoeboid and escaped through a pore on the parental cell wall; the other daughter cell remained within the parental cell wall. Pyrenoid ultrastructure and nucleomorph location, which are used as the main generic criteria of chlorarachniophytes, confirmed that the strain CCMP240 is a member of Lotharella. This alga, however, was clearly distinguished from other known Lotharella species by the presence of large vacuoles, unusual post‐cell division behavior and some unique ultrastructural characters. 相似文献
979.
Mitotic metaphase plates of a new species of the genus Macrostomum were studied using conventional Giemsa staining, Orcein staining and semi-thin sections stained after Richardson. Because of the ease in culturing it, this species has the potential to become the new model organism for developmental and evolutionary studies among the lower metazoa. The chromosome number was found to be 2 n = 8. Reaching a relative length of 45.9% of the haploid genome size, the chromosomes of one pair were significantly larger than all other chromosomes. Of the smaller pairs, chromosomes of one pair were slightly larger (relative length of 21.3%) than the chromosomes of the remaining two pairs (each with a relative length of 16.4%). All chromosomes were metacentric (2 m + 2 m + 2 m + 2 m ). For the first time, a diploid chromosome set of four pairs was described for the genus, as compared with previous studies showing predominantly 2 n = 6 for 20 different Macrostomum species. 相似文献
980.
Yoshihiko Sako Keshab Shrestha Aritsune Uchida Yuzaburo Ishida Shoichi Saito 《Journal of phycology》1991,27(2):309-315
Intraspecific variation among 36 strains of the freshwater alga Gonium pectorale Müller (Chlorophyceae) isolated from three geographically different locations in Tibet, Nepal, and Japan was investigated by isozyme analysis. Variation in isozyme patterns of eight enzyme systems (malate dehydrogenase, glutamate dehydrogenase, tetrazolium oxidase, lactate dehydrogenase, octanol dehydrogenase, xanthine dehydrogenase, phosphoglucomutase, and malic enzyme) of axenic and clonal cultures was revealed by polyacrylamide gel electrophoresis. Unweighted average linkage clustering, based on Jaccard's similarity coefficient, illustrated the high similarity between most strains from Nepal and all strains from the Ryukyu Islands (Japan). However, there was relatively low similarity between strains from Tibet and those from Nepal and Japan. Strains from the Ryukyu Islands (Japan) grouped into two clusters, and most Nepalese strains formed a single cluster, but Tibetan strains were heterogenous. 相似文献