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排序方式: 共有1007条查询结果,搜索用时 171 毫秒
991.
T. Aravinda B. Vinay Kumar M. S. Raghu L. Parusharam Srilatha Rao 《Nucleosides, nucleotides & nucleic acids》2020,39(4):630-647
AbstractContemporary research reveals an undemanding protocol for the catalytic synthesis of 1,2,4-oxadiazole-quinolinepeptide in the incidence of a cost-effective and reusable mesoporous ZrO2-supported Cu2O (Cu2ZrO3) catalyst. This paper depicts a unique system for peptide bond synthesis staying away from toxic solvents and reactants. The catalyst was reused for four cycles without noteworthy loss in the activity, and the catalyst was genuinely heterogeneous. The method followed a simple workup procedure, and no column chromatography was needed. Further, the synthesized 1,2,4-oxadiazole-quinolinepeptide ligand (L), and its complexes of type, [FeLCl2] and [CuL]Cl2 were synthesized and characterized by spectral and analytical techniques. An octahedral geometry has been projected for Fe(II) complexes, while the Cu(II) complex exhibits a square planar geometry. The binding properties of the complexes with CT-DNA were studied by absorption spectral analysis, followed by viscosity measurement and thermal denaturation studies. The photo-induced cleavage studies revealed that the complexes possess photonuclease activity against pUC19 DNA under UV–visible irradiation. 相似文献
992.
Sharma Vinay Kumar Rajender Sharma Vishal Kumar Yadav Ashok kumar Tiirola Marja Sharma Pushpender Kumar 《Molecular biology reports》2020,47(1):533-544
Molecular Biology Reports - In the present investigation, we report cloning, expression, purification and characterization of a novel Bleomycin Resistance Dioxygenase (BRPD). His-tagged fusion... 相似文献
993.
Y Boulanger P Legault A Tejedor P Vinay Y Theriault 《Canadian journal of physiology and pharmacology》1988,66(10):1282-1290
Papillary collecting duct tubules were prepared in gram quantities from the papillae of dog and pig kidneys. Measurements of substrate and oxygen utilizations by these tubules under both aerobic and anaerobic conditions showed the potential for both glycolysis and oxidative phosphorylation. Oxygen is not necessary to maintain a normal adenosine 5'-triphosphate concentration, but oxidative phosphorylation contributes to more than 65% of the metabolism under aerobic conditions in the two species. Both phosphorus-31 and proton nuclear magnetic resonance spectra recorded from extracts of dog cortex, red medulla, and papilla showed a clear gradient from cortex to papilla for osmolytes, such as glycerophosphorylcholine, sorbitol, inositol, betaine, and sugar phosphates. Other molecules identified in the spectra included glucose, sorbitol, mannitol, lactate, glutamine, alanine, threonine, and adenosine 5'-triphosphate. Conventional biochemical measurements supported these findings. An increase in osmolality from 300 to 600 mosmol/kg H2O for 120 min did not increase the glycerophosphorylcholine and sorbitol concentrations of dog papillary collecting ducts in vitro, but a small effect of a 24-h dehydration was detected in vivo. 相似文献
994.
In a crossover study bumetanide, 2 to 6 mg/d, was compared with furosemide, 40 to 160 mg/d, in the treatment of 10 patients with the nephrotic syndrome and massive edema. The two drugs, which both act on the loop of Henle, were found to be equally effective. Patients with renal insufficiency responded poorly to both drugs. 相似文献
995.
Gupta Surbhi Paliwal Ayushi Gupta Vinay Tomar Monika 《Plasmonics (Norwell, Mass.)》2020,15(3):661-669
Plasmonics - Present article demonstrates the effective tuning of thermo-optic (TO) properties with the Electro-Optic (EO) modulation characteristics of SBN60 thin films utilizing Waveguide coupled... 相似文献
996.
997.
V. Marshansky A. Fleser J. Noël S. Bourgoin P. Vinay 《The Journal of membrane biology》1996,153(1):59-73
During the preparation of a suspension of dog kidney proximal tubules by collagenase treatment, an uptake of FITC-albumin
was demonstrated. This process is attributed to the activation of receptor-mediated endocytosis leading to the appearance
of FITC-albumin into intracellular vesicular structures. The isolation of brush border membrane vesicles (BBMV) from the dog
kidney proximal tubules in suspension by the magnesium precipitation technique leads to the copurification of a large population
of endosomes. These endosomes were separated from BBM vesicles by a technique involving wheat-germ agglutinin. The enrichment
in BBM markers and in bafilomycin-sensitive ATPase activity was comparable in endosomes and BBM vesicles. However, the acridine
orange acidification assay showed a V-type ATPase-dependent acidification in endosomes but not in BBMV, demonstrating a different
orientation of the proton pumps in these structures. SDS-PAGE analysis also showed significant differences in protein pattern
of vesicles and endosomes. The most notable difference was the presence of 42–44 kDa and 20–24 kDa proteins in BBMV and their
complete absence in endosomes. Western blot analysis identified these proteins as actin and RhoA, among other small proteins,
respectively. Western blot experiments also demonstrated a different distribution of β-COP, β-adaptin, and RhoGDI in vesicles
and endosomes. The morphological aspect (electron microscopy) and sedimentation of endosomes in a 50% Percoll gradient identified
these structures as ``heavy endosomes' (buoyant density D= 1.036 g/ml). Flow cytometry analysis of heavy endosomes purified from tubules isolated in presence of FITC-albumin showed
the presence of FITC-albumin in up to 92% of these intracellular organelles. Western blot analysis using anti-FITC and anti-collagenase
antibodies allowed quantification of the FITC-albumin and collagenase A in the purified endosomes. Our results indicate that
heavy endosomes are formed during the preparation of the proximal tubules following activation of receptor-mediated endocytosis,
probably by soluble proteins. The suspension of tubules thus offers a experimental tool to study the protein reabsorption
and traffic of endosomal vesicles in the proximal tubules.
Received: 13 July 1995/Revised: 8 May 1996 相似文献
998.
999.
Gopal K. Khuller Kasinathan Chinnaswamy Reeta Taneja Nalini Penumarti Vinay S. Bansal 《Current microbiology》1982,7(1):49-51
Enzymes of phospholipid synthesis were studied inMycobacterium smegmatis ATCC 607 grown at 37 and 27°C. The synthesis seemed to be regulated, at least partly, at the phosphatidic acid level by the specificity of the acyltransferases. The individual phospholipid species were found to be regulated at the enzymatic level in the maintenance of membrane fluidity. 相似文献
1000.
The interrelationship among seasonality of cambium, wood formation, cell size variation, lignification, tree phenology and climatic factors has been examined in Moringa oleifera, a tropical evergreen tree. The vascular cambium in Moringa is a storied with a distinct seasonal variation in its structure due to dimensional changes in rays. Though cambium remains active throughout the year it is sensitive to water availability. Peak cambial cell division and rate of xylem differentiation are influenced by average rainfall during the monsoon period. Cambial cell division reaches higher up in the tree trunk when it is supporting a high number of branches and leaves. Statistical analysis of cell size variation and climate factors revealed that xylem cell development is greatly influenced by rainfall and rarely by temperature. Lengths of fusiform initials and vessel elements are positively correlated. The pattern of lignification during xylogenesis shows that the vessels are the first element to develop lignified walls and ray cells are the last elements to become lignified. Fiber cell walls show more syringyl lignin, while the cell walls of other xylem elements are characterized by relatively more guaiacyl lignin units. 相似文献