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Jaganmoy Bhattacharya Dhirendra Kumar Chaudhuri 《Biochimica et Biophysica Acta (BBA)/General Subjects》1974,343(1):211-214
The isolation and characteristics of a crystalline antithiamine factor from mustard seed, Brassica juncea is described.This oil bearing seed seems to contain at least two antithiamine factors, one of these is the methyl ester of 3,5-dimethoxy 4-hydroxy cinnamic acid (methyl sinapate). The chemical nature of the other is not yet known because it could not be isolated in pure form as yet. 相似文献
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105.
A new name for Limnophyes montanus Chaudhuri,Sinharay & Das Gupta (Diptera: Chironomidae) from India
P. K. Chaudhuri 《水生昆虫》2013,35(4)
Limnophyes nigripes is proposed as a replacement name for Limnophyes montanus Chaudhuri, Sinharay & Das Gupta, nee Limnophyes montanus Goetghebuer. 相似文献
106.
In this paper we present an application of deformable models for the segmentation of volumetric tissue images. The three-dimensional images are obtained using confocal microscope. The segmented images have been used for the quantitative analysis of the Fluorescence In Situ Hybridization (FISH) signals. An ellipsoidal surface initialized around the cell of interest acts as a deformable model. The deformable model surface voxels are subjected to various internal and external forces derived from underlying image features as well as externally imposed constraints. The deformable model converges to the optimum cell shape when the vector sum of all the forces acting on the model is zero. The result of segmentation is used to confirm the cell membership of the FISH signals and to reject all the signals that lie outside the cell nuclei. Three-dimensional region isolation and labeling technique is used to label and count the FISH signals per cell nucleus. A simple study on the effect of different segmentation methods over a quantitative analysis of FISH signals is also presented. 相似文献
107.
Endothelium-derived relaxing factor, identified as nitric oxide or its adducts, is metabolized to nitrate and excreted in the urine. Since blood pressures are lower in newborn infants compared to adults, we hypothesized that newborn infants would have increased excretion of nitrate on the day of birth. Neonatal urine was collected before 24 h of age when exogenous intake of nitrate was low. Two different analytical methods showed that nitrate accounted for >99% of nitrogen oxides in urine of healthy neonates and adults. The absolute micromolar concentration of nitrate in urine from infants was significantly below that of adults. When nitrate content was standardized for the reduced renal function in the newborn infant (creatinine content) and body mass (kilogram weight), the concentration of nitrate in neonatal urine was significantly higher than that of adults. Nitrate concentrations in the urine of prematurely born infants were twice that of nitrate measured in urine from term infants. These findings suggested that nitric oxide is produced in larger intravascular quantities in newborn infants versus adults. Thus, we postulated that nitric oxide released from a nitrosothiol would be metabolized to nitrate more readily by neonatal erythrocytes compared to red blood cells obtained from adults. Neonatal erythrocytes, suspended at concentrations of 8, 12, or 16 g per deciliter of hemoglobin, produced 1.7- to 2.1-fold more nitrate than equivalent hemoglobin concentrations of adult erythrocytes that were each incubated with S-nitroso-N-acetylpenicillamine (100 microM) over a 2-h period. Taken together, the studies of urinary nitrate in newborn infants and the ability of neonatal erythrocytes to generate nitrate are consistent with a robust production of nitric oxide immediately after birth. 相似文献
108.
A A Laxmi P Vijayalakshmi T N Kaimal A Chaudhuri Y Ramadas N M Rao 《Biochemical and biophysical research communications》2001,289(5):1057-1062
We report herein the design, synthesis, and transfection biology of a novel series of non-glycerol-based cationic lipids with lactic acid-derived head groups The synthetic procedure adopted herein for preparing 1-hydroxy-prop-2-yl head-group-based monocationic transfection lipids 1-7 is fairly straightforward and potentially applicable in designing other cationic lipids with lactic acid-derived head groups. A striking anchor-length dependency was observed in NIH3T3 cells in the sense that except lipid 4, all the other lipids were essentially transfection-inefficient. Ethidium bromide assay for the lipid:DNA interactions is consistent with the general observation that significant lipid:DNA interactions do not guarantee on improved transfection efficiency cationic lipid mediated gene delivery. Given its remarkable transfection properties and low cellular toxicity, lipid 4 is likely to find future use in the area of liposomal gene delivery. 相似文献
109.
Tripathi Laxmi Narayan Praveena M. Johns Ben Basu Jaydeep Kumar 《Plasmonics (Norwell, Mass.)》2018,13(5):1811-1816
Plasmonics - Nanoantenna-enhanced ultrafast emission from colloidal quantum dots as quantum emitters is required for fast quantum communications. On-chip integration of such devices requires a... 相似文献
110.
The crystal structure of the nickel(II) complex (C20H22N6S2Ni) of the N2S2 ligand hexan-2,5-dionebis(4-phenyl-thiosemicarbazone) has been solved using diffractometric data. The complex, exhibiting greater antibacterial activity than the free ligand, crystallizes in the space group C2 with a = 17.414(1) Å, b = 8.485(1) Å, c = 15.129(3) Å, β = 104.09(3)°, Z = 4, d(obsd) = 1.425 g cm?3, d(calc) = 1.438 g cm?3 and μ(Mo-Kga) = 10.978 cm?1. The structure has been refined by full-matrix least squares to a final R = 0.033 and Rw = 0.041 using 1743 reflections with I ≥ 3σ(I) out of 2049 unique reflections measured (2° ≤ gq ≤ 27°). The hydrogens were either located or placed in their calculated positions. The nickel(II) ion lies in the tetrahedrally distorted square planar ligand field of the tetradentate ligand forming two five membered and one seven membered chelate rings. It is observed that the lack of conjugation in the seven membered chelate rings of the present complex and of similar complexes leads to dissymmetry in the ring geometry. The metal ion is coordinatively unsaturated and available for additional coordination in its axial directions. 相似文献