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61.
Shuhichi Takahashi Susumu Kitanaka Michio Takido Ushino Sankawa Shoji Shibata 《Phytochemistry》1977,16(7):999-1002
From seedlings of Cassia torosa four dimeric hydroanthracenes have been isolated. Two, a pair of atropisomeric dimers consisting of two molecules o 相似文献
62.
The potential use of antibodies that selectively recognize either X-bearing or Y-bearing sperm is self-evident. Thus our attention was directed to the fact that under optimal conditions, H-Y antibody lyses 50% of mouse spermatozoa. Accordingly, we asked whether expression of H-Y antigen is haploid in spermatozoa from XY male mice heterozygous for the autosomal dominantSxr gene, for if H-Y expression were haploid, H-Y antibody would be expected to kill 75% of spermatozoa derived from these XY,Sxr/- males. However, maximal lysis remained at the 50% level, which indicates that haploid expression of H-Y antigen and the potential immunoselection of Y-(or X-) bearing spermatozoa are unlikely. 相似文献
63.
Wen-Chang Chang Sei-itsu Murota Susumu Tsurufuji 《Prostaglandins & other lipid mediators》1977,13(1):17-24
A main product (PI) transformed from arachidonic acid in carrageenin-induced granuloma in rats was structurally analysed. PI was converted to a more polar substance by the reduction with sodium borohydride. On the basis of the data on gas chromatography-mass spectrometry, its structure was identified with the hemiacetal derivative of 8-(1-hydroxy-3-oxopropyl)-9,12-heptadecadienoic acid (Thromboxane B2) 相似文献
64.
The levels of free amino acids in the cerebral cortex of acute and chronic uremic rats were examined. Amino acids significantly elevated were aspartate, glutamine, glycine, histidine, ornithine, phenylalanine, phosphoethanolamine and taurine, whereas 1-methyl histidine and 3-methyl histidine were specifically detected in uremic rats. Glutamate, arginine and carnosine disclosed a significant reduction. There was no change in the concentrations of γ-aminobutyrate and alanine. The above findings were essentially identical in both acute and chronic uremia. It was conjectured that these changes of amino acid levels in the brain might participate in the progress of uremic encephalopathy. 相似文献
65.
66.
Eiji Hara Tomoko Ohshima Takako Ishii Wataru Sugino Ko Tsutsui Susumu Nakada Nobuo Tsuchida Kinichiro Oda 《Experimental cell research》1992,198(2):250-258
The mechanism of induction of DNA synthesis in quiescent rat 3Y1 cells by the adenovirus E1A gene was investigated using the 3Y1 derivative cell lines g12-21, gn12RB1, and gn12RB2. The g12-21 cells express the E1A 12S cDNA and the latter two cells express both the E1A 12S cDNA and the human retinoblastoma susceptibility (Rb) gene at different levels in response to dexamethasone (dex). The cDNA sequences of E1A-inducible cell cycle-dependent genes, clone 3 and clone 16, were isolated by differential screening of a cDNA library constructed from dex-treated g12-21 cells. The quiescent 3Y1 cells induced c-fos and c-myc expression within 2 h after serum stimulation and expressed clone 16 and clone 3 transiently at around 8 h before the onset of DNA synthesis (10 h). In contrast, the quiescent g12-21 cells treated with dex expressed a high level of E1A at 6 to 8 h after treatment and expressed clone 16 and clone 3 at around 8 h without stimulation of c-fos and c-myc expression, suggesting that E1A bypasses the cell cycle early in G1. The half-maximal rate of DNA synthesis was reached in a much shorter time in dex-treated g12-21 cells (12 h) than in serum-treated 3Y1 cells (18 h), suggesting that E1A also bypasses the cell cycle at the G1/S boundary. The gn12RB1 and gn12RB2 cells were unable to induce DNA synthesis in response to dex presumably due to lower levels of E1A expression, although gn12RB2 but not gn12RB1 cells could express clone 16 and clone 3. These results suggest that the level of E1A required for bypass at the G1/S boundary is higher than that required early in G1. 相似文献
67.
Changes in Electrophoretic Patterns of Oocyte Proteins during Oocyte Maturation in Oryzias latipes 总被引:2,自引:2,他引:0
Takashi Iwamatsu Susumu Y. Takahashi Masamichi Oh-ishi Takashi Yokochi Hiroko Maeda 《Development, growth & differentiation》1992,34(2):173-179
Changes in the two-dimensional SDS-electrophoretic patterns of extracts of maturing denuded oocytes of the medaka ( Oryzias latipes ) were surveyed. In oocytes without follicular constituents several proteins became detectable in the area between the acidic and slightly basic proteins on the two-dimensional electrophoretograms, while a few of the protein spots disappeared during the process of oocyte maturation. The former proteins were detected also in oocytes that were induced to mature in vivo without breakdown of the germinal vesicle. Several proteins newly observed in extracts of post-vitellogenic oocytes during maturation after breakdown of the germinal vesicle were also identified by two-dimensional electrophoresis. Of several proteins that exhibited noticeable changes in maturing oocytes, only one spot incorporated 14 C-labeled amino acid during maturation, suggesting that post-translational modification of many proteins occurred during oocyte maturation. 相似文献
68.
Torosachrysone and two new naphthalenic lactones, isotoralactone and cassialactone, were isolated from the seeds of Cassia obtusifolia. Their structures were established as 9,10-dihydroxy-7-methoxy-3-methylene-1H-naphtho(2,3-c)dihydropyrone-1-one and 8-methoxy-4-methyl-1-oxo-4,10,11-trihydroxy-naphtho(2,3-c)oxepin, respectively. 相似文献
69.
Sumio Iwai Kazuo Nakata Teruyoshi Nagao Nobumaro Kawashima Susumu Matsuyama 《Planta》1981,152(5):478-480
Nine plants were produced from anthers of a somatic hybrid which had been obtained by fusion of Nicotiana tabacum L. and N. rustica L. protoplants. As determined by electrofocusing, the Fraction I protein of the original somatic hybrid had largesubunit polypeptides exclusively of the N. tabacum type. Two of the plants regenerated from anthers contained Fraction-I-protein large subunits exclusively of the N. rustica type. Since each plant was regenerated from a single cell, the somatic hybrid must have had cells containing both the N. tabacum and N. rustica chloroplast genome although the latter was not expressed. Possibilities to account for this non-expression of a chloroplast genome in the somatic hybrid are discussed. 相似文献
70.
Pure phloem sap from rice plant was collected by a method similarto the aphid technique using leafhoppers and planthoppers instead.A Yttrium-Aluminium Garnet laser was used to sever the insectstylets. Sap exuded from the plant through the stylet for upto 3 hr at a rate of 0.2 µl/hr. Analysis of the sap forsugars revealed that the only carbohydrate present was sucrose;its content was estimated to be 17% and remained at this levelfor 3 hr. (Received April 16, 1980; ) 相似文献