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921.
Ogawa Masami; Matsunaga Eisuke; Yamazaki Yoshio; Oyamada Kozo; Matsui Takashi; Tobitsuka Junzo 《Plant & cell physiology》1976,17(4):743-749
2-Ethyl-1-isopropoxycarbonyl-3-(4-tolylcarbamoyl)isourea [EITIU]stimulated both shoot and root growth of rice seedlings. Gibberellicacid [GA]-induced shoot elongation was further stimulated byEITIU, and the combined application of both compounds was shownto be distinctly synergistic. A similar synergistic action wasobserved in the growth of rice mesocotyls in the dark. The inhibitionof root growth caused by GA was overcome by combination withEITIU. The growth-stimulating activity of EITIU was not observedin lettuce hypocotyls.
1 This paper is Part I in the series "Plant growth-regulatingactivities of isourea derivatives and related compounds." (Received February 7, 1976; ) 相似文献
922.
Mechanical properties of the cell wall are represented by relaxationparameters. This paper describes an easy method of estimatingthe stress-relaxation parameters T0 and b, in which they canbe calculated using stress-relaxation data directly obtainedwith a simple tensile tester. The value of A is calculated fromthe relaxation data at time = 1, 2, 3 and 5 sec, and the valueof T0 is calculated by multiplying b by T, which is calculatedfrom the data at time = 0, 1 and 2 sec. (Received April 27, 1976; ) 相似文献
923.
Two kinds of monoclonal antibodies against HN protein of HVJ were isolated. In competitive binding assay, binding of one of these antibodies to HN protein did not inhibit binding of the other antibody to the same molecule. One of the antibodies, named HN-1 antibody, inhibited hemagglutination activity of HVJ and also blocked neuraminidase activity of the virus when fetuin and Ehrlich ascites tumor cells were used as substrates, but it did not inhibit the activity when neuramine-lactose was used as substrate. The other antibody, HN-2, did not inhibit hemagglutination activity or neuraminidase activity, but blocked HVJ-induced viral envelope-cell fusion, cell-cell fusion and hemolysis. The mechanism by which HN-2 antibody blocked the fusion process is discussed. 相似文献
924.
Glucose oxidase (β-d-glucose: oxygen 1-oxidoreductase, EC 1.1.3.4, GOD) was continuously released from Aspergillus sp. under mild ultrasound waves (20 kHz, 15 W). However, GOD was not released from the cells under normal conditions because of their thick wall. GOD production under ultrasound waves was optimum at pH 7.5 and 30°C and decreased with increasing ultrasonic frequency. Ultrasonic cavitation accelerated GOD release from the cells. Microscopic observation and determination of ATP and nucleic acids in the broth revealed that the mycelia were not broken during a 5 h reaction under ultrasound waves (15 W). About 10% of GOD produced in cells was released during the reaction. 相似文献
925.
Kenzo Yokozeki Shigeru Yamanaka Takashi Utagawa Koichi Takinami Yoshio Hirose Atsuo Tanaka Kenji Sonomoto Saburo Fukui 《Applied microbiology and biotechnology》1982,14(4):225-231
Summary Gel-entrapped whole cells of Enterobacter aerogenes, which has a transglycosylation activity, were used to produce adenine arabinoside from uracil arabinoside and adenine, in an appropriate water-organic cosolvent system. Cells of E. aerogenes entrapped with a hydrophilic photo-crosslinkable resin prepolymer, ENT-4000, or a urethane prepolymer, PU-6, had a high and stable transglycosylation activity. To improve the poor solubility in water of the substrate (adenine) and product (adenine arabinoside), dimethyl sulfoxide was selected as the cosolvent based on the criteria of operational stability of the immobilized biocatalyst and solubility of both substrate and product. Addition of 40% dimethyl sulfoxide to the reaction mixture permitted use of a high substrate concentration range which gave high productivity under homogeneous reaction conditions. The immobilized cells of E. aerogenes exhibited a markedly improved operational stability, retaining their initial level of activity during repeated use for at least 35 days at 60°C in 40% dimethyl sulfoxide. When the reaction was carried out with 150 mM uracil arabinoside and 50 mM adenine as the substrates, the yield of adenine arabinoside was maintained at 100% based on the molar ratio of adenine, throughout the reaction.Abbreviations used AraA
adenine arabinoside
- AraU
uracil arabinoside 相似文献
926.
Summary Twin and single sister chromatid exchanges (SCEs) induced by short treatments with mitomycin C (MC) and 4,5,8-trimethylpsoralen (TMP)-plus-near ultraviolet light (NUV) were analyzed in colcemid-induced endoreduplicated normal human and typical Fanconi's anemia (FA) fibroblasts with diplochromosomes. The induction rate of twin SCEs that had occurred in the first cycle (S1) after the treatment was 1.7–2.4 times higher in FA cells than in normal cells. The induction rate of single SCEs that had arisen during the second cycle (S2) long after the treatment was also much higher, though less than the twin SCE rate, in FA cells than the almost neglible rate after repair of cross-links and monoadducts in normal cells. These results in FA cells, which specifically lack the first half-excision step of the two-step cross-link repair but retain the normal monoadduct repair, indicate that MC or TMP cross-links remaining unrepaired are indeed responsible for higher inductions of twin (S1 exchange) and single SCEs (S2 exchange). Thus, these findings indicate that Shafer's model of replication bypass for cross-link-induced SCE, which predicts greatly reduced twin SCE formation in FA cells due to half cancellation, is apparently inadequate as such. We present three plausible models, incorporating the ordinary replication model, random unilateral cross-link transfer, and chromatid breakage/reunion, that can account for the probabilistic inductions of single and twin SCEs and even for no SCE formation.This work was supported in part by a grant-in-aid for cancer research from the Ministry of Education, Science and Culture, Japan 相似文献
927.
Kohji Jiro; Hagimoto Hirohumi; Yamamoto Ryoichi; Masuda Yoshio 《Plant & cell physiology》1982,23(8):1329-1336
The straightening process in the georeaction of the flower stalk(peduncle) of a poppy, Papaver Rhoeas L., was studied in relationto IAA transport in the peduncle and the receptacle. After thepeduncle had been formed, it first nodded. Cutting the flowerbud off at the nodding stage (stage 34 if the developmentis divided into 12 stages) caused rapid straightening of thenodding peduncle but the curvature was maintained if IAA wasapplied to the cut end of the decapitated peduncle. Applicationof 2,3,5-triiodobenzoic acid to the upper part of the pedunclejust below the flower bud at various growth stages caused immediatestraightening of the nodding peduncle. The IAA content in thepeduncle was lower at the straightening stages than at the noddingstage. Transport of 14C-IAA through the receptacle was lessat the straightening stages than at the nodding stage, whilethat through the peduncle was the same at these stages. Theseresults led to the conclusion that the straightening processof the poppy peduncle, which is considered to be a negativegeotropic response, is controlled by a decrease in the basipitaltransport of IAA from the flower bud to the peduncle throughthe receptacle. (Received April 12, 1982; Accepted September 13, 1982) 相似文献
928.
Cellulose tris(3,5-dimethylphenylcarbamate) (CDMPC) was coated on large-pore silica gels and used as a chiral stationary phase (CSP) for high-performance liquid chromatographic separation of enantiomers. The influences of pore size of silica gel, coating amount of CDMPC, coating solvent, and column temperature on chiral discrimination were investigated. CSPs prepared with a large-pore silica gel having a small surface area showed higher chiral recognition. The amount of CDMPC adsorbed on the silica gel influenced the chiral recognition of some racemates. Loading capacity of racemates increased with an increase of the amount of CDMPC supported on the silica gel, and a CSP coated with 45% CDMPC by weight can be used for both analytical and semi-preparative scale separations. The CDMPC, coated using acetone as the coating solvent, exhibited, in many cases, higher enantioselectivity than that obtained with tetrahydrofuran F as the coating solvent. © 1996 Wiley-Liss, Inc. 相似文献
929.
Nobuhiro Mori Kamon Shirakawa Ken-saku Uzura Yutaka Kitamoto Yoshio Ichikawa 《FEMS microbiology letters》1988,51(1):41-44
Abstract The degradation of choline by Candida tropicalis cells grown in a medium containing choline as a nitrogen source was examined. The degradation of choline by resting cells was stimulated by the addition of Cu2+ or glutathione, and inhibited by 2-mercaptoethanol or potassium cyanide. With feeding of [1,2-14 C]choline in the resting cell reaction, the release of 14 C-labelled ethylene glycol was observed on radio-gas-liquid chromatography. Ethylene glycol, as one of the degradation products, was also observed on thin-layer and gas-liquid chromatographies, and mass spectrometry. Thus, it is suggested that choline is converted to ethylene glycol and trimethylamine by C. tropicalis . 相似文献
930.
Masahito Katahira Taku Tsunekawa Akira Mizoguchi Mariko Yamaguchi Kahori Tsuru Hiromi Takashima Ryoma Terada 《Current issues in molecular biology》2021,43(1):107
The effects of amino acid variants encoded by the human leukocyte antigen (HLA) class II on the development of classical type 1 diabetes (T1D) and latent autoimmune diabetes in adults (LADA) have not been fully elucidated. We retrospectively investigated the HLA-DRB1 and -DQB1 genes of 72 patients with classical T1D and 102 patients with LADA in the Japanese population and compared the frequencies of HLA-DRB1 and -DQB1 alleles between these patients and the Japanese populations previously reported by another institution. We also performed a blind association analysis with all amino acid positions in classical T1D and LADA, and compared the associations of HLA-DRB1 and -DQB1 amino acid positions in classical T1D and LADA. The frequency of DRß-Phe-13 was significantly higher and those of DRß-Arg-13 and DQß-Gly-70 were significantly lower in patients with classical T1D and LADA than in controls. The frequencies of DRß-His-13 and DQß-Glu-70 were significantly higher in classical T1D patients than in controls. The frequency of DRß-Ser-13 was significantly lower and that of DQß-Arg-70 was significantly higher in LADA patients than in controls. HLA-DRß1 position 13 and HLA-DQß1 position 70 could be critical amino acid positions in the development of classical T1D and LADA. 相似文献