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61.
George M. Isakander Ibrahim El Shiekh El Khawad Hassan B. Zahran Elmer O. Schlemper 《Advanced Synthesis \u0026amp; Catalysis》1989,331(1):82-88
2-Aroyl-3-methyl-1 H-1,4-benzothiazine ylids ( 2a – k ) were prepared by alkylation of the corresponding 4H-benzothiazines 1 . The ylids 2 are labile at room temperature; proper analytical and 1H-n.m.r. data were obtained for their picrates. E.s.r. studies of u. v. irradiated polycrystalline form of ( 2 ; R1 = Me, R2 = H) gave evidence for a long-lived benzothiazinyl radical with the odd electron residing on nitrogen 6 . 相似文献
62.
63.
Michael H. Gordon Ibrahim Abdul Rahman 《Journal of the American Oil Chemists' Society》1991,68(8):574-576
The effect of various processing procedures on the composition and oxidative stability of coconut oil has been studied. The
crude oil is relatively stable but major reductions in oxidative stability occur during the bleaching of oil degummed with
phosphoric acid; during alkali refining; during the deodorization of oil degummed with citric acid and bleached; and during
the deodorization of oil processed with a combined phosphoric acid degumming and bleaching operation. The reasons for the
loss of oxidative stability during processing are discussed with reference to changes in the composition of the oil. Residual
traces of citric acid or phosphoric acid play an important role in stabilizing processed oils. The tocopherol content is also
important, although no additional stabilization of the oil occurs on adding levels of tocopherol above those present naturally
in the crude oil. A combined phosphoric acid degumming and bleaching process leads to smaller losses of tocopherols than sequential
treatments. 相似文献
64.
Fine flour from corn and the isolated starch were dextrinized in the presence of acid and irradiated with y-rays. Starch irradiated with high doses of y-rays was highly modified while fine flour was less affected. The irradiated starch was reduced with sodium borohydride and then hydrolysed. Erythritol and other compounds were identified in the hydrolysate. It was concluded that the C2-C3 bonds in the intermediate glucose units are probably broken by irradiation. Such hypothesis was confirmed by periodate oxidation, hydrolysis with α-amylase and ferricyanide number determination of the irradiated starch. 相似文献
65.
Anna Liguori Alessandro De Vita Giulia Rossi Luisa Stella Dolci Silvia Panzavolta Chiara Gualandi Laura Mercatali Toni Ibrahim Maria Letizia Focarete 《International journal of molecular sciences》2022,23(6)
In the clinical management of solid tumors, the possibility to successfully couple the regeneration of injured tissues with the elimination of residual tumor cells left after surgery could open doors to new therapeutic strategies. In this work, we present a composite hydrogel–electrospun nanofiber scaffold, showing a modular architecture for the delivery of two pharmaceutics with distinct release profiles, that is potentially suitable for local therapy and post-surgical treatment of solid soft tumors. The composite was obtained by coupling gelatin hydrogels to poly(ethylene oxide)/poly(butylene terephthalate) block copolymer nanofibers. Results of the scaffolds’ characterization, together with the analysis of gelatin and drug release kinetics, displayed the possibility to modulate the device architecture to control the release kinetics of the drugs, also providing evidence of their activity. In vitro analyses were also performed using a human epithelioid sarcoma cell line. Furthermore, publicly available expression datasets were interrogated. Confocal imaging showcased the nontoxicity of these devices in vitro. ELISA assays confirmed a modulation of IL-10 inflammation-related cytokine supporting the role of this device in tissue repair. In silico analysis confirmed the role of IL-10 in solid tumors including 262 patients affected by sarcoma as a negative prognostic marker for overall survival. In conclusion, the developed modular composite device may provide a key-enabling technology for the treatment of soft tissue sarcoma. 相似文献
66.
67.
Guven Ibrahim Cinar Kenan 《International Journal of Mechanics and Materials in Design》2019,15(4):695-714
International Journal of Mechanics and Materials in Design - A method based on X-ray micro-CT was introduced to create realistic representative volume elements (RVE) for particulate-filled... 相似文献
68.
Ibrahim R. Shimi Nabila A. Maroun Mamdouh Y. Kamel Hemmat H. Ragheb Mohga M. Badran 《Lipids》1974,9(6):368-373
Gas liquid chromatographic analysis of the fatty acid methyl esters from eggs ofDermacentor andersoni Stiles (Ixodidae) revealed the presence of significant quantities (15% total fatty acids) of an unidentified component with a retention time between C18∶3−C22∶0 fatty acids. Smaller amounts of the unidentified component (ca. 5% total fatty acid) also were detected in host rabbit serum. Purified, the unidentified component's methyl ester collected from the tick eggs by preparative gas liquid chromatography was partially identified and characterized by chemical and spectroscopic analyses. The evidence suggests that the unidentified component is a methyl branched C15 tricarboxylic acid containing two vicinal carboxylic acid groups. Biosynthesis of the unidentified component by the tick is under investigation. 相似文献
69.
Redox systems based on potassium, sodium or ammonium peroxodisulphate or potassium periodate as oxidant and glucose, thiourea, sodium thiosulphate or potassium pyrosulphite as reductant were incorporated in the dyeing bath of nylon-6 under a variety of conditions. An acid dye, namely Kiton Scarlet 4 R was used. The colour strength and dye fixation enhanced outstandingly in presence of the redox system, depending upon kind and concentration of the redox components. Raising the dyeing temperature from 30 to 60°C caused significant improvement in colour strength. The same holds true for duration of dyeing up to 60 min. Beside association of the dye with nylon-6 by salt-like bond, a free radical mechanism was suggested. 相似文献
70.
Claude Leger Lucie Fremont Didier Marion Ibrahim Nassour Marie-Françoise Desfarges 《Lipids》1981,16(8):593-600
This paper describes evidence of (n−3) and particularly of 22∶6 (n−3) fatty acid enrichment in trout lipoproteins as well
as in vitellogenin, egg lipovitellin and oil globule. Among the lipoproteins, HDL and LDL were the main forms of blood lipid
transport, whereas phospholipids and cholesteryl esters are the preferential chemical carriers for (n−3) fatty acid transport.
However, cholesteryl esters were less important as esterified fatty acid carriers than in man. Taken together with the data
obtained in mammals, our results suggest that there may be a relationship between EFA activity and the distribution of the
EFA among the lipoprotein lipid fractions in vertebrates, irrespective of the EFA series. Administration of an (n−3) fatty
acid deficient diet for three months prior to trout spawning produced a significant increase in egg lipid content, primarily
as a result of the increase of the oil globule composed almost exclusively of triacylglycerols. This diet decreased the 22∶6
(n−3), as well as the (n−3) fatty acid contents of lipoproteins, lipovitellin, vitellogenin and the oil globule. In contrast,
the (n−3) fatty acid level was always higher in lipoproteins and lipovitellin than in the vitellogenin and the oil globule.
Moreover, the relative levels of 22∶6 (n−3) and total (n−3) fatty acids were quite similar in lipoproteins and lipovitellin
on the one hand, and in vitellogenin and the oil globule on the other. These findings suggest a direct relationship between
the two forms of plasma lipid transport and the two egg compartments. During ovogenesis, dietary lipids seemed to be diverted
from the adipose tissue and essentially deposited in the egg. 相似文献