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111.
Growth Regulation of Dark-grown Dwarf Barley Coleoptile by the Endogenous IAA Content 总被引:1,自引:0,他引:1
Growth curves of dark-grown coleoptiles of 11 isogenic coleoptilardwarf strains of barley (Hordeum vulagare L. cv. Akashinriki:uzu, 5, 77, 97, 105, 125, 131, 133, 136, 145 and 148) were simulatedwith a logistic equation and the endogenous IAA contents ofthe barley strains were determined. Growth analysis of the dwarfbarley coleoptiles revealed that the final coleoptile lengthwas correlated with the growth rate on the 2nd day after germination(r=0.897), when the growth rate was about maximum. The endogenousIAA Content of the barley strains, measured fluorometrically,indicated that on the 2nd day, the dwarf strains contained lessendogenous IAA than the normal Strain. The IAA content on the2nd day was correlated to the growth rate on the 2nd day (r=0.907,except for Strain 145) and the final coleoptile length (r=0.933,except for strains 77 and 145). The correlation, however, wasnot significant on the 3rd day. These results suggested thatthe dwarfism of the dark-grown coleoptiles of the barley Strainsexamined is primarily controlled by the endogenous IAA content.
1 Present address: Department of Biology, Faculty of Science,Osaka City University, Osaka 558, Japan. (Received February 1, 1982; Accepted April 13, 1982) 相似文献
112.
Michio Takido Susumu Kitanaka Shushichi Takahashi Tomohisa Tanaka 《Phytochemistry》1982,21(2):425-427
Two new yellow pigments, germitosone and methylgermitorosone, were isolated from the seedling of Cassia torosa. The structures of these substances were established as 3,7 dimethyl - 6 - methoxy - 1 - oxo - 2,3,8,9 - tetrahydroxy - 1,2,3,4 - tetrahydroanthracene and 6,9 dimethoxy - 3,7 - dimethyl - 1 - oxo - 2,3,8 - trihydroxy - 1,2,3,4 - tetrahydroanthracene respectively. 相似文献
113.
Susumu Terabayashi 《Journal of plant research》1981,94(2):141-157
The floral vasculature in three allied genera,Plagiorhegma, Jeffersoria andAchyls is investigated, and the results are compared with those ofEpimedium andVancouveria which are related closely toPlagiorhegma andJeffersonia.
The vasculature in the receptacle ofPlagiorhegma andJeffersonia is similar, but that ofAchlys is much simpler. Slightly different trace patterns are observed in the sepals ofPlagiorhegma andJeffersonia. InJeffersonia, the 3-trace condition leaving 2 or 3 gaps is most frequently observed, but inPlagiorhegma traces of a double nature leaving a single gap are more frequent. The traces to the innermost sepals, petals and stamens
are usually of a double nature leaving a single gap in both genera. Regular division and fusion are not observed in the receptacular
stele. The vascular differentiation between sepals and petals is more advanced inPlagiorhegma andJeffersonia than inEpimedium andVancouveria. InAchlys, the traces are all staminal and single throughout their course.
Two parts recognized in the pistils ofPlagiorhegma, Jeffersonia andAchlys are traversed by independent vasculature. The comparisons of pistil morphology including vasculature ofPlagiorhegma, Jeffersonia, Achlys, Epimedium andVancouveria lead to the interpretation that the pistils are based on the same morphological plan. The probable evolutionary trend in
pistil is then suggested in these five genera. 相似文献
114.
Mark J. Ottenbreit Susumu Inoue Ward D. Peterson James C. Lin 《Bioelectromagnetics》1981,2(3):203-215
Human marrow cells were irradiated with 2450-MHz CW microwaves in a fluid-filled waveguide irradiation system. Cell exposure was conducted by placing a marrow cell suspension in 20-μl glass microcapillary tubes that were positioned in the exposure chamber, and irradiated at power densities from 31 to 1,000 mW/cm2 (with corresponding specific absorption rates of 62 to 2,000 mW/g) for 15 minutes. The temperature of the sample was maintained at a fixed point. Sham-irradiated (SI) and microwave-irradiated (MWI) cells were cultured in a methylcellulose culture system for neutrophil colony proliferation. There was no reduction in neutrophil colony number on days 6–7 or 12–14 in cells exposed at 31 or 62 mW/cm2, but as the power density was increased to 1,000 mW/cm2, there was a reduction in colony number of MWI cells compared with SI cells. The microwave interaction with the human neutrophil colony-forming cells was apparently not related to temperature rise, or to the state of cell cycle, and was irreversible. 相似文献
115.
Summary The structure of mesenchymal cells distributed in some of the hypendymal organs of the circumventricular system in the cat and rat was demonstrated after intravenous injection of high doses of horseradish peroxidase. These cellular elements were observed in the vicinity of blood vessels of the organon vasculosum laminae terminalis, subfornical organ and area postrema. Electron-microscopically, these cells located between the basal laminae of the brain parenchyma and the blood capillaries show long cellular processes encircling fenestrated capillaries. Light and electron-microscopic examination revealed that this cell type is identical with the horseradish peroxidase-uptake cells, previously reported in the vicinity of the hypophysial portal system. Such phagocytic cells may be considered as a cellular component intervening between the brain parenchyma and the blood stream, playing a role in selective barrier functions in the above-mentioned circumventricular organs where a blood-brain barrier in the classical sense of the definition is lacking.This work was supported by grant No. 437002 from the Ministry of Education, Science and Culture, Japan 相似文献
116.
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
117.
Leaves of different ages from B. calycinum were exposed to 14CO2in light during day and night. The labelling pattern on thechromatogram differed with leaf age. Young leaves had similarpatterns to those of C3 plants during both day and night. Matureleaves showed high incorporation of 14C into C4 acids, especiallyat night. In contrast, no significant difference with leaf agewas observed in the pattern of dark 14CO2 fixation products.Study of the enzyme activity and the content of titratable acidat each leaf age suggested that high incorporation of 14C inC4 acids during the night was due to the simultaneous absorptionof CO2 by both enzymes RuDPcarboxylase and PEPcarboxylase. (Received November 24, 1977; ) 相似文献
118.
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
119.
120.
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