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1.
The influence of wilting on the levels of free proline, soluble proteins, reducing sugars, starch and on the activities of
nitrate reductase, invertase, amylase and pyrophosphatases have been studied in the leaf tissue of five cultivars of pearl
millet at their vegetative stage under pot culture conditions. The metabolic changes could not be correlated with the yield
behaviour of the cultivars under a drought condition in the field. 相似文献
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The effect of high supercoil densities on the melting characteristics of a supercoiled DNA has been studied. It is found that although the melting temperature increases abruptly on converting a linear DNA merely into the relaxed circular form, it falls back substantially at high supercoil densities. It is further predicted, in such cases, that the number of melted base pairs should be significantly enhanced even at the physiological temperature, which may facilitate the binding of other molecules to the highly supercoiled DNA. 相似文献
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A binding isotherm in the form of a modified McGhee-Von Hippel equation is proposed, on the basis of thermodynamical considerations, to include the non-cooperative binding of extended ligands to supercoiled DNA, where a stretch of non-B form may be present under superhelical stress. It is then studied, on the basis of a non-linear Scatchard plot, how the presence of an intercalating ligand can relax the supercoiled molecule and thus destabilise the non-B stretch, which may be recognised by the existence of a significant kink in the Scatchard plot. 相似文献
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Lahiri V. L. Srivastava R. K. Hazra D. K. Gupta A. K. Painuly N. K. Sharma S. K. Khanna-Hazra P. Khanna P. Gupta R. K. Pathak Manish 《Cell biochemistry and biophysics》1994,24(1-3):9-14
Cell Biochemistry and Biophysics - Despite attempts to maintain asepsis, good manufacturing practices, and the use of terminal sterilization by millipore filtration, the nuclear practitioner is... 相似文献
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Antibodies were raised in rabbits against 70S ribosomes, 50S and 30S ribosomal subunits individually. Purified immunoglobulins
from the antiserum against each of the above ribosomal entities were tested for their capabilities of precipitating 70S, 50S
and 30S ribosomes. The observations revealed the following: (i) The antiserum (IgG) raised against 70S ribosomes precipitates
70S ribosomes completely, while partial precipitation is seen with the subunits, the extent of precipitation being more with
the 50S subunits than with 30S subunits; addition of 50S subunits to the 30S subunits facilitates the precipitation of 30S
subunits by the antibody against 70S ribosomes. (ii) Antiserum against 50S subunits has the ability to immunoprecipitate both
50S and 70S ribosomes to an equal extent. (iii) Antiserum against 30S subunits also has the property of precipitating both
30S and 70S ribosomes. The differences in the structural organisation of the two subunits may account for the differences
in their immunoprecipitability. 相似文献