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Salwa A. Maksoud M. Nabil El Hadidi Wafaa Mahrous Amer 《Vegetation History and Archaeobotany》1994,3(4):219-224
Physical and chemical analyses of beer residues recovered from a vat site at Hierakonpolis (Upper Egypt) were carried out. Radiocarbon dates of the residues suggest a dating of 3500–3400 cal B.C. and are believed to represent the oldest known beer in the world. Macroscopic and microscopic examinations of the residues revealed the presence of intact remains of grains and spikelets of wheat and barley, as well as fragments of dates and grape pips. Chemical analyses included percentages of sample ingredients, pH and total soluble ions, quantitative determinations of sugars, carboxylic acids and free amino acids. A total of 25 compounds were identified, which are components of fermentation processes that are believed to have formed in connection with the preparation of what is called Nekhen-Hoffman beer. 相似文献
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Mohamed Ahmed El-Nabarawi Rehab Nabil Shamma Faten Farouk Samar Mohamed Nasralla 《AAPS PharmSciTech》2018,19(5):2174-2184
Dapsone (DPS) is a unique sulfone with antibiotic and anti-inflammatory activity. Owing to its dual action, DPS has a great potential to treat acne. Topical DPS application is expected to be effective in treatment of mild to moderate acne conditions. Invasomes are novel vesicles composed of phosphatidylcholine, ethanol, and one or mixture of terpenes of enhanced percutaneous permeation. In this study, DPS-loaded invasomes were prepared using the thin film hydration technique. The effect of different terpenes (Limonene, Cineole, Fenchone, and Citral) in different concentrations on the properties of the prepared DPS-loaded invasomes was investigated using a full factorial experimental design, namely, the particle size, drug entrapment, and release efficiency. The optimized formulation was selected for morphological evaluation which showed spherical shaped vesicles. Further solid-state characterization using differential scanning calorimetry and X-ray diffractometry revealed that the drug was dispersed in an amorphous state within the prepared invasomes. Finally, the ability of the prepared DPS-loaded invasomes to deliver DPS through the skin was investigated in vivo using wistar rats. The maximum in vivo skin deposition amount of DPS was found to be 4.11 mcg/cm2 for invasomes versus 1.71 mcg/cm2 for the drug alcoholic solution, representing about 2.5-fold higher for the invasomes compared to the drug solution. The AUC0–10 calculated for DPS-loaded invasomes was nearly 2-fold greater than that of DPS solution (14.54 and 8.01 mcg.h/cm2 for the optimized invasomes and DPS solution, respectively). These results reveal that the skin retention of DPS can be enhanced using invasomes. 相似文献
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Nabil?OmriEmail author Noura?Khemiri Manef?Abderrabba Fathi?Moussa Sabri?Messaoudi 《Journal of molecular modeling》2018,24(9):270
In this paper, we perform the synthesization of carbon nanoparticles for active principle vectorization, with the suggestion of a reaction mechanism of tryptophan methyl ester addition on [60]fullerene. Firstly, we studied the effect of tryptophan form on its addition reaction on [60]fullerene. So, in order to determine the preferred environment that makes this reaction the most favorable, we considered all tryptophan possible forms in our investigation: the molecular, the zwitterionic, and the dibasic forms. Secondly, we investigate the proposed reaction mechanism of tryptophan methyl ester addition on [60]fullerene using theoretical thermodynamic calculation. Our hypothesis suggests the formation of azomethine ylide molecule in a first step followed by its addition on [60]fullerene in the second step by the photo-addition reaction involving the oxygen in its singlet state. The stability of each reactive intermediate involved in this mechanism is verified thermodynamically. The 12 most stable conformations of azomethine ylide were observed through potential energy surface analysis. They were obtained by a relaxed scan of the four dihedral angles. The calculations were conducted on the optimized geometry of fulleropyrrolidine mono-adduct and the bulk values of its thermodynamic constants were also determined. Infrared spectra observed in 100–4000 cm?1 region confirmed our hypothesis suggesting the first step of azomethine ylide formation followed by the second step of azomethine ylide addition on [60]fullerene by ν(Caliphatic-C-N), ν(Caromatic-C-N) and δ(N-H) coupled with ν(C-N) absorption bond. 相似文献
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Gestational surrogacy and the role of routine embryo screening: Current challenges and future directions for preimplantation genetic testing 下载免费PDF全文
E. Scott Sills Robert E. Anderson Mary McCaffrey Xiang Li Nabil Arrach Samuel H. Wood 《Birth defects research. Part C, Embryo today : reviews》2016,108(1):98-102
Preimplantation genetic screening (PGS) is a component of IVF entailing selection of an embryo for transfer on the basis of chromosomal normalcy. If PGS were integrated with single embryo transfer (SET) in a surrogacy setting, this approach could improve pregnancy rates, minimize miscarriage risk, and limit multiple gestations. Even without PGS, pregnancy rates for IVF surrogacy cases are generally satisfactory, especially when treatment utilizes embryos derived from young oocytes and transferred to a healthy surrogate. However, there could be a more general role for PGS in surrogacy, since background aneuploidy in embryos remains a major factor driving implantation failure and miscarriage for all infertility patients. At present, the proportion of IVF cases involving GS is limited, while the number of IVF patients requesting PGS appears to be increasing. In this report, the relevance of PGS for surrogacy in the rapidly changing field of assisted fertility medicine is discussed. Birth Defects Research (Part C) 108:98–102, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
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The compound eye of the opaque-eye mutant ofDrosophila melanogaster was investigated by means of electron microscopy to determine the morphological and physical properties of ommatidial elements. These elements in the mutant were found to differ from those of the wild-type flies in the following ways: (1) The cuticular lens was thinner than that of the control and lacked the typical lamellar construction. (2) The Semper cells were irregular in shape and contained many membranous inclusions similar to those found in degenerating cells; also their nuclei contained virus-like particles. (3) The primary pigment cells contained an abundance of drosopterin-containing granules which were lacking in those of wild-type flies. (4) The superior and inferior central photoreceptor cells were misplaced and their rhabdomeres evidenced some degeneration. (5) The secondary pigment cells had only one type of pigment granules instead of the three types found in the control. These morphological changes in ommatidial elements induced physical abnormalities such as the apparent opaqueness of the eye, the lack of a pseudopupil, the probable disability of the photoreceptor cells to respond to light and the inability of the dioptric system to produce utilizable geometrical images. 相似文献