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21.
Brassinolide-Induced Elongation of Inner Tissues of Segments of Squash (Cucurbita maxima Duch.) Hypocotyls 总被引:1,自引:0,他引:1
Brassinolide (BR) stimulated elongation of etiolated squashhypocotyl segments with outer tissues removed, as well as thatof unpeeled segments, while IAA has no effect on peeled segments.BR changed the mechanical properties of cell walls of the innertissue. The inner tissue is probably the target tissue in BR-inducedelongation.
1Dr. Susumu Kuraishi died in 1993. 相似文献
22.
Naoko Miyano-Kurosaki Hideki Nakashima Koji Ichiyama Kazuhiko Inazawa Hidenori Tabata Hideyuki Tanabe Kiyotaka Ohnishi Hiroshi Mizusawa Yukako Ohshiro Naoki Yamamoto 《Microbiology and immunology》1994,38(10):813-818
A subclonal cl.1–14 cell was established from a monocytic cell line U937 by a limiting dilution method. The anti-HIV-1 activity of some antiviral compounds was evaluated in HIV-1-infected cl.1–14 cells. The results demonstrated that although AZT was a potent inhibitor of HIV-1 replication in cl.1–14 cells, its 50% effective concentration (EC50) values was 80 times higher than that in HIV-1 infected MT-4 cells; the EC50 of AZT was 0.16 μM and 0.002 μM in cl.1–14 and MT-4 cells, respectively. In contrast, the anti-HIV-1 activity of ddA, ddI and ddC in cl.1–14 cells was comparable to that in MT-4 cells. The antiviral activity of nevirapine, dextran sulfate, curdlan sulfate and T22 did not differ significantly between the cl. 1–14 and MT-4 cells. The antiviral activity of several compounds in the HIV-1-infected cl.1–14 cells was similar to that in the HIV-1jr -fl -infected human peripheral macrophages. Our results suggest that cl.1–14 cell cultures are very useful for estimating antiviral activity and more advantageous than the use of peripheral blood macrophages. 相似文献
23.
Tsukio Masegi Satoshi Nakamura Masami Fukuoka Kazuo Kitai Yataro Ichikawa Naoki Watanabe Yoshiro Niitsu 《Biotechnology letters》1993,15(11):1107-1110
Summary We prepared various TNF- derivatives by protein engineering techniques. Mutant 471, in which 7 N-terminal amino acids were deleted and Pro8Ser9Asp10 was replaced by ArgLysArg, had a 8-fold higher antitumor activity against mouse L929 cells than wild-type TNF-. The additional substitution of Ala156 or Leu157 by more hydrophobic amino acids enhanced the activity of mutant 471. These results suggested that the combinational mutations in the N- and C-terminal regions of TNF- are effective for the improvement of antitumor activity. 相似文献
24.
Zenjiro Osawa Tsubura Morota Kenichi Hatanaka Toshihiro Akaike Kei Matsuzaki Hideki Nakashima Naoki Yamamoto Eiichiro Suzuki Hiroshi Miyano Tohru Mimura Yutaro Kaneko 《Carbohydrate polymers》1993,21(4):283-288
Sulfopropyl curdlan was synthesized, its structure was determined, and the anti-HIV activity was compared with that of standard curdlan sulfates obtained with piperidine N-sulfonic acid in dimethyl sulfoxide. It was shown that sulfopropyl curdlan exhibits weaker anti-HIV activity than curdlan sulfate. Curdlan sulfates were synthesized with a SO3-pyridine complex in a heterogeneous phase. It was shown from 13C-NMR spectra of acetylated curdlan sulfates that they had a different substituent distribution from standard curdlan sulfate. The cytotoxicity of the curdlan sulfates was attributed to their heterogeneous structure. 相似文献
25.
Bulb canker of garlic caused byEmbellisia allii was newly detected in Japan. Symptoms of the disease are described and the morphological characteristics of the causal fungus are illustrated and described. 相似文献
26.
Masaharu Inouye Yoshio Takada Naoki Muto Teruhiko Beppu Sueharu Horinouchi 《Molecular genetics and genomics : MGG》1994,245(4):456-464
A 29 kb shuttle cosmid vector, pTYS507, was constructed from a cryptic Micromonospora griseorubida plasmid and the Escherichia coli cosmid pJB8. Subcloning of mycinamicin II biosysnthesis genes in pTYS507 led to the identification of a DNA region that could complement a mutant of M. griseorubida that lacked both hydroxylase and epoxidase activities. Nucleotide sequence and mutational analysis suggested that a single P-450-like protein catalyzes both reactions. 相似文献
27.
28.
Naoyuki Nakahama Ryosuke Okano Yuichiro Nishimoto Yusuke Nakatani Asato Noishiki Naoki Ogawa 《Entomological Science》2023,26(2):e12545
Wetland biodiversity is currently declining on a global scale. Wetland biodiversity understanding is critical for determining the wetlands' conservation value. In this study, Macroplea Samouelle, 1819 (Coleoptera: Chrysomelidae) was discovered in Aomori Prefecture, Honshu Island, Japan. Only two Macroplea species have been recorded in Japan, M. japana (Jacoby, 1885) and M. mutica (Fabricius, 1792). Macroplea japana had been unrecorded for 60 years before being rediscovered in Honshu Island in 2022, and a single adult M. mutica female was discovered in Hokkaido Prefecture in 2003. The discovered individuals were concluded to be M. mutica based on morphological and molecular analyses. Although morphological differences were observed with the Eurasian M. mutica individuals, the male genitalia was nearly identical to M. mutica. For the molecular phylogenetic analysis based on COI and 28S sequences, Macroplea individuals in Japan were clustered with M. mutica on the Eurasian Continent. This is the first record of this species on Honshu Island (and the second in Japan), as well as the first record of adult males. This species would require conservation policies and additional distributional surveys. 相似文献
29.
30.
Qiulin Li Naoki Yamamoto Seiji Morisawa Akira Inoue 《Journal of cellular biochemistry》1993,51(4):458-464
Long-chain fatty acids and their acyl-CoA esters are potent inhibitors of nuclear thyroid hormone (T3) receptor in vitro. In the present study, we obtained evidence for acyl-CoA binding activity in the nuclear extract from rat liver. The activity sedimented at a position (3.5 S) identical with that of the T3 receptor, and the two activities sedimented together. Similarly, they coeluted on DEAE-Sephadex. After partial purification of the receptor, it was again inhibited strongly by acyl-CoAs. Heat stability and a partial trypsin digestion of the receptor both suggested that the action site of oleoyl-CoA overlapped the T3-binding domain of the receptor. In addition, thyroid hormone receptor β1, synthesized in vitro, bound oleoyl-CoA specifically and its T3-binding activity was inhibited. The dissociation constant for oleoyl-CoA binding to the partially purified receptor was 1.2 × 10?7 M. This value as well as its molecular size distinguished the nuclear binding sites from the cytoplasmic fatty acid/acyl-CoA binding proteins. Oleoyl-CoA had no effect on the glucocorticoid receptor, another member of the nuclear hormone-receptor superfamily. From these results, we propose that thyroid hormone receptor is a specific acyl-CoA binding protein of the cell nucleus. 相似文献