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1.
4′,5′-Unsaturated nucleosides are obtained by the action of 1,5-diazabicyclo-[5.4.0]undec-5-ene on N1- and N3-(methyl 2,3,4-tri-O-acetyl-β-d-glucopyranosyluronate)-5-fluorouracil. The 2H1 conformation of N1- and N3-(methyl 4-deoxy-α-l-threo-hex-4-enopyranosyluronate)-5-fluorouracil has been established by 1H-n.m.r. and c.d. methods. Interaction of the heterocyclic base and the double bond of the sugar moiety is demonstrated. 相似文献
2.
The heterogeneity of bromophenol blue from different commercial sources was revealed by paper chromatography. Isopropanol:ammonia:water (20:1:2) as the solvent system gave the best separation. A variety of impurities: violet, pink, light blue and yellow coloured ones were observed. Two of the yellow fractions showed a spectral shift to red in the presence of ammonia vapour. The respone of the main dye component with the anionic chromotropes such as heparin and hyaluronate was found to be metachromatic similar to that exhibited by the dye solution and not due to a polychromatic effect. The metachromatic effect was blocked by FeCl3 as in the case of cationic dye metachromasy. The observed metachromatic colour is not one of the colours which characterize those resulting from changes caused by pH. 相似文献
3.
4.
Kalaiyarasi Ramalingam Scott R. Eaton Wayne L. Cody Joseph A. Loo Annette M. Doherty 《Letters in Peptide Science》1994,1(2):73-79
Summary A series of phosphopeptides Tyr(PO3H2)-Val-Pro-Xxx-Leu (Xxx=Met, Met(O), Nle, Dab or Cys), derived from the native platelet-derived growth factor- receptor (PDGF-) sequence, has been prepared to study their interaction with the src-homology 2 (SH2) domains of the p85 subunit of PI3 kinase. The phosphopeptides were synthesized using Fmoc methodology incorporating N-Boc dibenzyl-protected phosphotyrosine (Boc-Tyr[PO3(Bzl)2]) as the N-terminal amino acid, since the benzyl groups can be removed during resin cleavage with TFA. Only peptides containing methionine were found to exist partially as S-benzyl sulfonium salts after TFA cleavage from the resin. The desired peptide could be obtained from the S-benzyl sulfonium salt by hydrogenolysis. 相似文献
5.
Surfacing activity and food utilisation in the obligatory air-breathing fish ophiocephalus striatus as a function of body weight 总被引:1,自引:1,他引:0
E. Vivekanandan 《Hydrobiologia》1977,55(2):99-112
Reared in cylindrical aquaria containing different depths of water (2.5 to 70 cm) the obligatory air-breathing fish Ophiocephalus striatus, belonging to different weight classes (0.1, 0.75, 10, 20 and 41 g), was forced to swim vertically a longer or shorter distance per surfacing. Surfacing frequency was a depth-dependent, activity in individuals weighing less than 20 g in all weight classes, the frequency was nearly 2 times more in the series fed ad libitum on fish muscle, than in the one where the fish were starved. Owing to the sustained surfacing activity and the consequent fatigue, the test individuals hung to the surface for a definite period. Neither frequency nor duration of hanging was depth-dependent. Mean hanging durations for the feeding series were 1.1, 3.8, 5.9, 7.9 and 8.8 hr/day in the 0.1, 0.75, 10, 20 and 41 g weight classes, respectively; the corresponding values for the starving series were 1.3, 15.0, 13.0, 12.7 and 12.8 hr/day. The distance swum by the feeding fish increased from 57 to 681 m/day and from 61 to 507 m/day in the 0.1 and 41 g individuals exposed to the minimum and maximum aquarium depths. Feeding rate, which was a depth-dependent activity, decreased from 280 to 113 g cal/g live fish/day with increasing weight. Rate and efficiency of conversion also decreased with increasing body weight; in larger fish conversion was dependent on volume rather than on depth of the aquarium. O2 uptake of feeding fish was about 6 times higher than the starving ones of the tested weight classes at different aquarium depths.This paper is part of a thesis submitted by the author (from A.P.A. College, PALNI) to Madurai University in partial fulfillment of the requirement of the Ph. D. degree. Contribution No. 12 under a research scheme granted to Dr. T. J. Pandian by the UGC (New Delhi). The author is grateful to Dr. T. J. Pandian for valuable guidance, financial support and encouragements. 相似文献
6.
K E Linder M D Wen D P Nowotnik K Ramalingam R M Sharkey F Yost R K Narra A D Nunn W C Eckelman 《Bioconjugate chemistry》1991,2(6):407-414
BATO (boronic acid adduct of technetium dioximes) complexes, TcCl(dioxime)3BR, were prepared in which the boron substituent (R) was the protein-reactive 2-carboxy-4-phenyl isothiocyanate (CPITC). The 99Tc complexes, where the dioxime was either dimethylglyoxime (DMG) or cyclohexanedione dioxime (CDO), were prepared and characterized. The 99mTc complex TcCl(DMG)3CPITC was prepared from a freeze-dried kit and used to label B72.3 (anti-TAG.72) and NP-4 (anti-CEA) whole antibodies, and the NP-4 F(ab')2 fragment. SDS-PAGE electrophoresis indicated that the labeling reagent was strongly bound to antibody. The labeled antibodies displayed high binding to affinity columns and good tumor uptake in GW39 tumor-bearing mice. 相似文献
7.
8.
Effects of feeding and starvation on growth and swimming activity in an obligatory air-breathing fish 总被引:4,自引:4,他引:0
Reared in (tubular) aquaria containing different depths of water, Ophiocephalus striatus (0.7 g, 4.5 cm body length), an obligatory air-breathing tropical fish, swam long or short distances to enable themselves to exchange atmospheric air. In each tested depth (2.5, 5.0, 15.5, 31.0 and 40.0 cm) series, one group was starved, while the other was fed ad libitum twice a day on fish muscle. In the shallowest water (2.5 cm depth), the feeding group surfaced 1,294 times, travelling 64.7 m at an energy cost of 20.4 mg dry fish substance/g live fish/day, against those exposed to the deepest water (40 cm depth), which expended 35.8 mg/g/day, swimming 1,503.4 m on 1,879 visits to the surface. The starving group surfaced only 482 times, travelling 24.1 m at an expense of 5.8 mg/g/day in the shallowest water, while those at 40 cm depth surfaced 504 times, swimming 403.2 m at an energy cost of 7.4 mg/g/day. Owing to the sustained swimming activity and the consequent fatigue, the test individuals belonging to both groups in all the tested series hang to the surface for a definite interval, repaying the O2 debt. Observations were also made to assess the duration of hanging to precisely estimate the distance travelled. Irrespective of changes in depths of water, the duration of hanging to surface was only 3.0 hr/day for the feeding groups, while it was as much as 15.5 hr/day for the starving groups. The maximum sustained metabolic level of O.striatus reared in 40 cm depth was equivalent to 1.23 ml O2/g/hr, which is about 2 times higher than the value reported for the active metabolism of swimming Oncorhynchus nerka at 15°C in Brett's (1964) respirometer. O.striatus reared in 2.5 cm depth fed 32.0 mg and converted 6.7 mg dry food/g live fish/day, while those exposed to the deepest water fed 49.1 mg, but converted only 5.5 mg/g/day. Culturing obligatory air-breathing fishes in shallow waters will be advantageous. 相似文献
9.
Mohanan Manoj Vadakkenchery Pushpanathan Anunanthini Padmanabhan Sarath Sasikumar Thelakat Jayanarayanan Ashwin Narayan Selvarajan Dharshini Ramalingam Sathishkumar Ram Bakshi Chinnaswamy Appunu 《Journal of plant research》2021,134(5):1083-1094
Journal of Plant Research - The glyoxalase pathway is a check point to monitor the elevation of methylglyoxal (MG) level in plants and is mediated by glyoxalase I (Gly I) and glyoxalase II (Gly II)... 相似文献
10.
S.A. Syam Kumar Raghavendra Holla Prabakar Sukumar Sriram Padmanaban Nagarajan Vivekanandan 《Reports of Practical Oncology and Radiotherapy》2013,18(2):87-94