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81.
Dr. Dimitar R. Peev 《Plant Systematics and Evolution》1982,140(2-3):235-242
Flavonoid patterns of several provenances ofVeronica triloba, V. sublobata, andV. hederifolia s. str. have been investigated. 7-0-glucuronides of apigenin and luteolin as well as of 6-substituted (6-hydroxyluteolin
and hispidulin) and 3′-methylated (chrysoeriol) derivatives represent characteristic accumulation tendencies in theV. hederifolia group. The three species show slightly different flavonoid profiles.V. hederifolia exhibits a cumulative pattern of all compounds occurring either inV. triloba orV. sublobata, thus supporting the hypothesis of an allopolyploid origin ofV. hederifolia. 相似文献
82.
Michael R. Boarder Alexandre J. Lockfeld Jack D. Barchas 《Journal of neurochemistry》1982,38(2):299-304
Abstract: A specific and sensitive radioimmunoassay procedure for Metenkephalin[Arg6 ,Phe7 ] which allows its measurement in regions of the rat brain is described. The antiserum was raised against the methionine sulphoxide derivative of the peptide, and all samples and standards were oxidized with hydrogen peroxide prior to use in the assay with chloramine T-oxidized 125 I-labelled Met(O)-enkephalin[Arg6 ,Phe7 ]. The only significant cross-reactivity was 30% with the reduced heptapeptide Met-enkephalin[Arg6 ,Phe7 ]. The assay showed less than 0.15% cross-reactivity with fragments of the heptapeptide and with leucine-enkephalin-containing peptides. Acid acetone extraction of rat striatum followed by Sephadex G-50 chromatography and reverse-phase high pressure liquid chromatography showed that essentially all immunoreactivity co-chromatographed with Met-enkephalin[Arg6 ,Phe7 ]. This confirmed the specificity of the assay and showed that the striatum does not contain a high concentration of larger molecular weight forms with the heptapeptide at the COOH terminus. Distribution of the heptapeptide followed that of methionine enkephalin, with highest concentrations in the globus pallidus, intermediate levels in caudate-putamen and hypothalamus, and low levels in cortex and cerebellum. 相似文献
83.
John S. Hothersall Salmata Zubairu Patricia McLean A. Leslie Greenbaum 《Journal of neurochemistry》1981,37(6):1484-1496
The effect of 6-aminonicotinamide (6AN) treatment on the activities of alternative pathways of glucose metabolism in 20-day-old rat brain was evaluated by measurements of yields of 14CO2 from glucose labeled with 14C on carbons 1, 2, 3 + 4, or 6 and uniformly labeled glucose, and from the incorporation of 14C from specifically labeled glucose into lipids by brain slices from cerebral hemispheres and cerebellum. At the highest dose of 6AN used (35 mg/kg body weight) there was a significant decrease in the 14CO2 yields via the pentose phosphate pathway, the glycolytic route, tricarboxylic acid (TCA) cycle, and via the glutamate-gamma-aminobutyric acid pathway. Giving a graded series of doses (20-35 mg 6AN/kg body weight) revealed a hierarchy of responses in which the pentose phosphate pathway, lactate, glyceride-glycerol, and fatty acid formation were most sensitive, followed, in sequence, by the pyruvate dehydrogenase reaction, the glutamate-gamma-aminobutyrate route and, finally, the TCA cycle. The nature of the blocks in the various pathways was examined by the use of metabolite profiles. 相似文献
84.
Four known sesquiterpene lactones, tomentosin, ivalin, 4-epi-isoinuviscolide and gaillardin, together with three new lactones, inuchinenolides A, B and C, were identified in the whole plant of Inula britannica var. chinensis. 相似文献
85.
Summary The relative toxicity of nitrapyrin 2-chloro-6-(trichloromethyl) pyridine and ATC (4-amino-1, 2, 4-triazole) on the growth
of chick peas (Cicer arietinum L.) cow peas (Vigna sinensis L.), green beans (Phaseolus vulgaris L.), green peas (Pisum sativum L.) and mung beans (Phaseolus aureus Roxb.) and their effectiveness as nitrification inhibitor were studied under greenhouse conditions. ATC produced no toxicity
symptoms in green peas, whereas resulted in leaf chlorosis in cow peas, chick peas and green beans. However, nitrapyrin toxicity
appeared as leaf chlorosis in cow peas, and interveinal chlorosis in chick peas. Moreover, nitrapyrin-treated green beans
and peas developed leaf curling and cupping. Although ATC had no significant effect on growth, a suppression in plant growth
was associated with nitrapyrin application. Furthermore, green beans was the most resistant and chick peas the most sensitive
to nitrapyrin. Nitrapyrin was more effective nitrification inhibitor than ACT, especially at the lower rates. 相似文献
86.
Steroid acid esters, synthesized by modifying the 17-ketol side chain of prednisolone, were tested for their in vitro ability to stabilize heavy mitochondrial lysosomes prepared from rat liver. Membrane stabilization was determined by assessing capability of steroids to decrease extrusion of the marker enzymes (acid phosphatase, beta-glucuronidase and aryl sulfatase) from lysosomes incubated in hypo-osmotic sucrose-Tris acetate buffer. Results indicated that prednisolone (1) significantly inhibited the lysosomal release of acid phosphatase as did the new anti-inflammatory steroid, methyl 20-dihydroprednisolonate. Methyl prednisolonate exhibited weak membrane stabilization capacities and 20-dihydroprednisolonic acid, a metabolic product of methyl 20-dihydroprednisolonate, showed virtually no membrane stabilization. 相似文献
87.
Accessory reproductive organs of male rat were found to contain high activities of glucosamine-6-phosphate synthase (glucosaminephosphate isomerase (glutamine-forming), EC 5.3.1.19). Castration caused drastic reduction (75%) in the enzyme activity of ventral prostate. Testosterone propionate administration restored the enzyme activity while cortisol and estradiol-17β did not cause any effect. Cycloheximide blocked the stimulation caused by testosterone. 相似文献
88.
89.
Lipoxygenbase-derived products of arachidonic acid mediate stimulation of hexose uptake in human polymorphonuclear leukocytes 总被引:3,自引:0,他引:3
D A Bass M J Thomas E J Goetzl L R DeChatelet C E McCall 《Biochemical and biophysical research communications》1981,100(1):1-7
The titration of metal-freed bovine α-lactalbumin with Mg2+ ions causes a two-stepped decrease in the tryptophan fluorescence quantum yield and a pronounced spectral shift towards shorter wavelengths, which seems to be a result of the binding of two magnesium ions to the protein molecule. The magnesium binding constants evaluated from the fluorimetric Mg2+-titration are 2·103 and 2·102 M?1. Mg2+ ions in millimolar concentrations almost do not influence the binding of Ca2+ ions to the protein. 相似文献
90.
Marie-Luise Blue David L. Williams 《Biochemical and biophysical research communications》1981,98(3):785-791
Apo II and vitellogenin were detected in sera of nonestrogenized roosters by radioimmunoassay. Tamoxifen (30mg/kg) raised basal serum apo II more than 50 fold and vitellogenin more than 15 fold. Serum accumulation of apo II was biphasic in response to increasing doses of tamoxifen. This biphasic response was reflected in the relative rates of hepatic apo II synthesis. The tamoxifen metabolites, hydroxytamoxifen and desmethyltamoxifen, and the triphenylethylene antiestrogen, CI 628, also increased serum apo II. These studies show that the expression of vitellogenin and apo II genes occurs at a basal rate prior to exogenous estrogen treatment. These experiments also demonstrate that the triphenylethylene antiestrogens have agonist activity in the chicken when very sensitive techniques are used to measure estrogen-regulated proteins. 相似文献