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11.
A simple and rapid technique is reported for the preliminary screening of fungi-toxic extracts/samples by direct spotting onto silica gel plates and subsequent over-spraying with a fungal spore suspension. After incubation fungi-toxicity is indicated by a growth inhibition zone, the area of which is related to the concentration of the sample.B.K. Rana and V. Taneja are with the Department of Biochemistry. Faculty of Science, Banaras Hindu University, Varanasi 221005, India; U.P. Singh is with the Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi 221005, India. 相似文献
12.
S V Rana S Mehta J S Chopra C K Nain U K Dhand J Mehta 《Journal of medical primatology》1984,13(4):205-217
An experimental model of protein calorie malnutrition (PCM) was created in young rhesus monkeys. Ulnar and tibial nerves from six monkeys with PCM, six rehabilitated and 12 control monkeys were studied for lipid composition and activity of myelin marker enzyme. Total lipids, myelin marker lipids and activity of myelin marker enzyme, 2', 3'-cyclic nucleotide 3' - phosphohydrolase were decreased, while esterified cholesterol and free fatty acids were increased in PCM as compared to controls. There was partial recovery in myelin marker lipids and complete restoration of other lipids on nutritional rehabilitation. 相似文献
13.
phenyl 2-acetamido-2-deoxy-4,6-O-(p-methoxybenzylidene)-3-O-[4,6-O-(p-methoxybenzylidene)-β-d-alactopyranosyl]-α-d-galactopyranoside (3) was prepared from phenyl 2-acetamido-2-deoxy-4,6-O-(p-methoxybenzylidene)-3-O-(2,3,4,6-tetra-O-acetyl-β-d-galactopyranosyl)-α-d-galactopyranoside by zemplén deacetylation, followed by reaction with p-methoxybenzaldehyde in the presence of anhydrous zinc chloride. The selective benzoylation of 3 gave the 3′-benzoate which, on condensation with 2,3,4-tri-O-benzyl-α- l-fucopyranosyl bromide under catalysis by halide ion, afforded a crystalline trisaccharide from which the title trisaccharide was obtained by debenzoylation followed by catalytic hydrogenolysis. 相似文献
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Summary Soil nitrate profiles under seven treatments of an experiment on intercropping in row crops were studied at sowing and the after harvesting of different crops. The estimates of NO3
––N in these profiles indicate that intercropping in the row crops grown during the rainy season considerably reduced leaching loss of nitrates. Where the main crop receives the recommended fertilizer amount and the intercrop a small additional application, intercropping greatly reduced the amount of unutilized nitrates and hence their leaching beyong root zone. 相似文献
16.
Interactions between magainin 2 and Salmonella typhimurium outer membranes: effect of lipopolysaccharide structure 总被引:11,自引:0,他引:11
The role of the outer membrane and lipopolysaccharide (LPS) in the interaction between the small cationic antimicrobial peptide magainin 2 and the Gram-negative cell envelope was studied by FT-IR spectroscopy. Magainin 2 alters the thermotropic properties of the outer membrane-peptidoglycan complexes from wild-type Salmonella typhimurium and a series of LPS mutants which display differential susceptibility to the bactericidal activity of cationic antibiotics. These results are correlated with the LPS phosphorylation pattern and charge (characterized by high-resolution 31P NMR) and outer membrane lipid composition, and are compared to the bactericidal susceptibility. LPS mutants show a progressive loss of resistance to killing by magainin 2 as the length of the LPS polysaccharide moiety decreases. Disordering of the outer membrane lipid fatty acyl chains by magainin 2, however, depends primarily upon the magnitude of LPS charge rather than the length of the LPS polysaccharide, contradicting the proposal by Weiss et al. [Weiss, J., Beckerdite-Quagiata, S., & Elsbach, P. (1980) J. Clin. Invest. 65, 619-628] that the sugar side chain of LPS shields the negative charges of the outer membrane surface. While disruption of outer membrane structure most likely is not the primary factor leading to cell death, the susceptibility of Gram-negative cells to magainin 2 is associated with factors that facilitate the transport of the peptide across the outer membrane, such as the magnitude and location of LPS charge, the concentration of LPS in the outer membrane, outer membrane molecular architecture, and the presence or absence of the O-antigen side chain. 相似文献
17.
The effect of human recombinant DNA interferon-alpha type A on inositol lipid and diacylglycerol metabolism was investigated in Daudi lymphoma whole cells and isolated nuclei. In isolated nuclei after 90 min of interferon treatment an enhanced rate of PIP2 phosphorylation and an increase of DAG mass were observed. In whole cells, after 1 min of interferon treatment, there was a rapid and transient shift of DAG mass apparently not related to inositol lipid modifications, thus indicating the presence in nuclear and cytoplasmic compartments of inositol lipid fractions with different metabolic features in response to interferon-alpha. 相似文献
18.
Sharma Amey Sharma Avani Rana Apoorva Niraj Ravi Ranjan Kumar 《International journal of peptide research and therapeutics》2020,26(4):2137-2145
International Journal of Peptide Research and Therapeutics - The Centers for Disease Control and Prevention (CDC) reported earlier that more than 11,000 people died from a methicillin-resistant... 相似文献
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