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1.
Amino acid germanate compounds are synthesized by the chemical reaction of germanium dioxide with a selected amino acid in the presence of an alkali medium at a suitable elevated temperature. Amino acids included in the novel synthesis include histidine, methionine and glutathione. The study evaluated their effects on induction of interleukin-12 and interferon-γl in Swiss albino Webster rats. The new germanium compounds, especially bis-methionino germanate, are considered as good interferon inducer that significantly enhance the immunologic function. 相似文献
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Yasser M. Loksha Per T. Jrgensen Erik B. Pedersen Mahmoud A. El‐Badawi Ahmed A. El‐Barbary Claus Nielsen 《Journal of heterocyclic chemistry》2002,39(2):375-382
5‐Alkyl‐4‐benzyl‐1,3‐dihydroimidazol‐2‐ones ( 3a‐d ) and 5‐alkyl‐4‐benzyl‐1,3‐dihydroimidazole‐2‐thiones (7a‐d) were prepared via Dakin West reaction on DL‐phenylalanine with the appropriate aliphatic acid anhydrides followed by hydrolysis and reaction with potassium cyanate or potassium thiocyanate. Compounds 3a‐d were alkylated with ethoxymethyl chloride to give the alkylated imidazoles 5a‐d which were considered analogues of Emivirine with deletion of carbonyl group at the 4‐position. Alkylation of 7a‐d afforded the corresponding S‐alkylated derivatives 8a‐p which in a similar way were considered analogues of S‐DABO. However all the imidazole derivatives were devoid of activity against HIV. 相似文献
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Tissues samples of chicken /blood, liver, spleen, fat, pancreas, kidney, lung, breast muscle, brain, femur, faeces, egg yolk, white of egg/, were analyzed for scandium concentration. ScCl3 was applied intravenously /1 mg kg–1 body weight/. High scandium concentrations were found in the liver /34. 35 ppm/, spleen /15.46 ppm/, and lung /15.52 ppm/ three days after application. This experiment shows that accumulation of scandium occurs in the yolk of egg but not in the white of the egg. 相似文献
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Hassan M. Badawi 《Journal of Molecular Structure》1995,343(1-3):117-124
The conformational stability and structure of 2,3-dimethylpropenal, 2,3-difluoropropenal and their 3,3-dimethyl and 3,3-difluoro derivatives were investigated utilizing ab initio calculations with 3-21G and 6-31G basis sets. For 2,3-dimethylpropenal and 3,3-difluoropropenal the s-trans was predicted to be the low-energy form. In the case of 3,3-dimethylpropenal and 2,3-difluoropropenal the s-cis was predicted by both levels of calculation to be the more stable conformer. Full optimization was performed at the transition states and the barriers to internal rotation were calculated. Methyl and fluorine substitution were found to significantly increase the barrier to interconversion in propenal. The relative change in the barrier depends on the position and the type of the substituent. The trans to cis barrier in 2,3-dimethylpropenal was calculated to be about 3 kcal mol−1 greater than that in 3,3-dimethylpropenal, while the cis to trans barrier in 2,3-difluoropropenal was predicted to be about 7 kcal mol−1 higher than the corresponding one in 3-3-difluoropropenal. 相似文献
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From the decay of their most intense -ray, /or rays/, the half-lives of24Na,31Si,49Ca,52V,139Ba,142Pr,153Sm,159Gd,165Dy,166Ho,175Yb,187W,233Th and239U have been redetermined. 相似文献
10.
E. M. S. Azzam A. M. Badawi A. R. E. Alawady A. Soliman 《Journal of Dispersion Science and Technology》2013,34(4):540-547
The purpose of this work is to study the self-assembling of some synthesized thiol surfactants namely (mercaptopropane-, mercaptohexane-, mercaptooctane-, and mercaptodecane sodium sulfonate) on the fabricated gold nanoparticles. The self-assembling of these surfactants on gold nanoparticles characterized using different techniques such as FTIR spectroscopy, UV spectroscopy, and transmission electron microscopy (TEM). Spectroscopic evidence suggests that the synthesized thiol surfactants have been attached to the gold nanoparticles. The effect of self-assembling of these surfactants on the size of the gold nanoparticles was studied using TEM images. The growth of the gold nanoparticles was investigated with respect to the increase of alkyl chain in the synthesized thiol surfactants. The results show that the stabilization of gold nanoparticles was affected by the increase in alkyl chain length of these surfactants. The effect of gold nanoparticles on the interfacial tension and the emulsion stability of these surfactants with crude oil was studied. 相似文献