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31.
Two freshwater sponge species, Ephvdatia fluviatilis and Spongilla alba, were maintained in a continuous-flow laboratory culture system at several different water temperatures. Experimental results suggest that sponge growth rate is affected by water temperature and that it is affected differently in the two species. The results correlate well with field observations on species abundance at different water temperatures and thereby support the view that water temperature is a factor determining seasonality in these species. 相似文献
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Two cases of mycotic keratitis caused by the Colletotrichum state of Glomerella cingulata and Acrophialophora fusispora are reported for the first time. Both the isolates produced experimental corneal lesions in rabbit eyes but A. fusispora was more pathogenic. The experimental infection was more severe, with both the fungi, in rabbits pretreated with cortisone as compared with untreated animals. In vitro A. fusispora was most sensitive to miconazole and tolciclate followed by clotrimazole, amphotericin B and lactones while clotrimazole exerted maximum inhibitory effect on Colletotrichum followed by miconazole, lactones, amphotericin B and arnebins. Arnebins and tolciclate were inactive respectively against A. fusispora and Colletotrichum. Of the 3 drugs tested in vivo, against A. fusispora keratitis in rabbit, amphotericin B showed better results than tolciclate and miconazole. 相似文献
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The variations observed during earlier studies in the activity of NADP+-isocitrate dehydrogenase (EC. 1.1.1.42) in a strain of Aspergillus niger were found to be related to the extent of washing of mycelium. As a result the mycelium washed four times with phosphate buffer (0.05 M, pH 7.5), the enzyme activity present in 4 and 8 days old fungal mycelia increased five- and two-fold, respectively. In vivo studies showed a complete loss of enzyme activity in mycelia resuspended in HCl-KCl buffer (0.02 M, pH 2.2) containing citric acid (13 mM or more). The in vitro studies revealed 50% loss of enzyme activity in presence of 3.6 to 5.2 mM citric acid. However, in case of Aspergillus niger ATCC 1015, which produced less citric acid than the above strain, a much higher citric acid concentration (13 to 26 mM) was required to cause 50% loss of enzyme activity. These findings suggest a correlation between citric acid inhibition of NADP+-isocitrate dehydrogenase and the ability of A. niger to accumulate citric acid in the medium. 相似文献
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S. Gopal K. K. Maggon T. A. Venkitasubramanian K. G. Mukerji 《Biologia Plantarum》1971,13(5-6):396-401
Some biochemical properties ofTrigonella foenum-groecum infected withPeronospora trifoliorum have been investigated. Qualitative changes were observed in lipids, coumarins, amino acids and indole compounds only. A quantitative study of the phosphate content was also carried out. Neutral lipids did not show any significant changes. In addition to the fourteen phospholipid bands, the infected leaves contained a new band corresponding in Rf to phosphatidic acid or polyglycerophosphate. Seven coumarins were present in both the extracts. In addition 3-hydroxy coumarin, 5-hydroxy-4-methylcoumarin and 7-hydroxy-4-methyl-coumarin were detected in infected leaves. Higher levels of indole acetic acid and three of its derivatives were observed due to infection. Infection altered the free amino acid content. Tryptophan appeared and the total phosphate content increased. Increase in phenols and indoles suggest a higher respiratory rate whereas a higher content of inorganic phosphate suggests uncoupling of phosphorylation from respiration. 相似文献
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Summary Groundnut (TMV-2) seeds treated with 25 ppm boron solution germinated more quickly than the seeds supplied with deionized water. The borontreated seedlings also elongated rapidly in the initial phase of the growth even though all their different organs contained excess boron contents (with chlorosis in the leaves) than those of the control seedlings. However, the accentuation in the growth of treated seedlings was proceeded only upto a certain period (12 days after treatment); but further stimulation in the later phase of the growth was almost inhibited with ever increasing amounts of boron in the hypocotyl, plumule and leaves (which were severely chlorotic) and even brought about a deleterious effect on the total growth at the end of 21 days when compared to the controls. 相似文献
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Two new steroidal glycosides, agaveside A and B, isolated from the fruits of Agave cantala were characterized as 3 beta-O-[beta-D-xylopyranosyl-(1----2),beta-D-xylopyranosyl-(1----3), beta-D-glucopyranosyl-(1----3)-[beta-D-xylopyranosyl-(1----3)-beta-D- galactopyranosyl-(1----2)]-beta-D-glucopyranosyl]-(25R)-5 alpha-spirostane and 3 beta-O-[beta-D-xylopyranosyl-(1----2), beta-D-xylopyranosyl-(1----3)-beta-D-glucopyranosyl-(1----3)- [beta-D-galactopyranosyl-(1----2)]-beta-D-glucopyranosyl]-(25R)-5 alpha-spirostane. The structures were elucidated by a combination of 13CNMR spectroscopy, chemical degradation and fast atom bombardment mass spectrometry. 相似文献
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gamma-Glutamyl transpeptidase (gamma-GT), its substrate (GSH) and hydrolytic product (L-glutamic acid) were measured biochemically in mouse reproductive tissues. The epididymal caput and seminal vesicles showed the highest specific activities of gamma-GT, while GSH and L-glutamic acid were widely distributed in all tissues. Histochemically, gamma-GT displayed a strong apical and supranuclear reaction and a moderate basal activity in the ductuli efferents, a weak luminal reaction in the first, a moderate apical reaction in the second and a strong apical and supranuclear reaction in the third segment of the epididymal caput. In the epididymal corpus and cauda, the gamma-GT reaction was confined to the tubular lumina but an apical reaction was also present in the cauda. The daily administration of acivicin (12 mg/kg body weight), an irreversible inhibitor of gamma-GT, for 14 days resulted in a 60% suppression of the enzyme activity in the epididymal caput, while the gamma-GT inhibition in the kidney was greater than 95%. The treatment caused no change in the activity of alanyl aminopeptidase. Histochemically, the basal and supranuclear gamma-GT activities in the ductuli efferents and the third epididymal segment were suppressed, but the apical reactions were maintained. The in-vivo suppression of epididymal gamma-GT activity may have implications in the control of post-testicular sperm maturation. 相似文献