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排序方式: 共有89条查询结果,搜索用时 15 毫秒
1.
Lydia Saidi Dr. Djenisa H. A. Rocha Dr. Oualid Talhi Dr. Yamina Bentarzi Prof. Dr. Bellara Nedjar-Kolli Dr. Khaldoun Bachari Dr. Filipe A. Almeida Paz Dr. Luisa A. Helguero Prof. Dr. Artur M. S. Silva 《ChemMedChem》2019,14(10):1041-1048
Breast and prostate cancers are frequently treated with chemotherapy. Several novel chemicals are being reported for this purpose, particularly synthetic and natural benzophenones. This work reports the synthesis of substituted 2-hydroxybenzophenones through 1,4-conjugate addition/intramolecular cycloaddition/dehydration of nitromethane on key intermediate chromones. Structures were extensively studied by means of 2D NMR spectroscopy and single-crystal XRD. Their cytotoxicity was evaluated in vitro in two breast cancer cell lines (MDA-MB-231 and T47-D) and one prostate cancer cell line (PC3). The most potent compound exhibited good cytotoxic effects against the three cancer cell lines (IC50 values ranging from 12.09 to 26.49 μm ) and induced cell-cycle retardation only on prostate cancer cells, which suggested that it might exert cell-type-specific effects. 相似文献
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A study of the noise performance of gate overlapped polycrystalline silicon thin-film transistors (TFTs) is presented. Low-frequency noise measurements were carried out on n- and p-type samples fabricated by excimer laser crystallization. It is shown that the carrier number fluctuation model applies not only to n-type but also to p-type devices. The density of oxide traps was extracted from the noise measurements and was of the order of 1018-1019 eV-1 cm-3 相似文献
4.
Kouzaev G.A. Deen M.J. Nikolova N.K. Rahal A.H. 《Microwave and Wireless Components Letters, IEEE》2004,14(6):265-267
We study the influence of the technologically caused eccentricity of a circular-pad via-hole. We derive an eigenvalue equation using a rigorous method based on a linear transformation of the via-hole polar coordinates. The eigenvalue equation is used to compute the modal resonant frequencies and the modal fields of the eccentric via. It is shown that the via-hole misalignment shifts the modal frequencies and influences its frequency band. The proposed model is verified with published experimental data, and is also compared with results generated with the full-wave simulator Agilent Momentum-2002. 相似文献
5.
Said Ghaout Alain Louveaux Anne Marie Mainguet Max Deschamps Youssef Rahal 《Journal of chemical ecology》1991,17(8):1499-1515
A field study of the food eaten by solitary desert locusts was carried out in a winter breeding area in Mauritania. The food eaten, determined by the plant epidermis found in fecal pellets, was compared to the plant's availability in the habitat.Schouwia purpurea, well represented in the diets, was dominant at the study site. Adults had a preference forTribulus terrester. Growth and feeding on these two plants were compared. The high water content ofS. purpurea leaves limited the dry matter eaten and slowed down growth. Glucosinolates were separated and quantified by gas chromatography. There are 132mol/g dry matter in green leaves. In multiple choice tests, with paper disks, glucosinolate extracts were phagostimulant at a low concentration (21mol/g dry matter) and repulsive at a higher one (214mol/ g dry matter). Biting behavior onS. purpurea was recorded and analyzed on video. The importance ofSchouwia purpurea in desert locust habitats and its defenses is discussed. 相似文献
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Charles Rahal 《Computational Economics》2016,48(1):183-188
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Meriem Yatim Rahal El Kahkahi Taoufik El-Askri Samia El Oirdi Fouad Benhnini Adnane El Yaacoubi Abdelmounaim Mouhajir Ali Amechrouq Abdelilah Rahou Majida Hafidi Rachid Zouhair 《Journal of the American Oil Chemists' Society》2022,99(8):685-696
Morphological characterization was investigated by agro-morphological criteria related to carob seed size in four different moroccan regions collected in 2018 and 2019. There was no significant difference (p ≤ 0.05) on the seeds lengths and widths. However, a significant difference between seeds thickness and total seeds weight per pod (p ≤ 0.05) were observed between these four populations. The fatty acid, sterol, tocopherol, hydrocarbon, and the unoxygenated composition of carob seed extracts (Ceratonia siliqua L.) were studied. The mean fat yield of the seeds obtained is 1.53%–2.17%, 2.14%–2.15%, 1.61%–1.62%, 1.71%–1.75% for, respectively, the P1 (Meknes), P2 (Fez), P3 (Khemisset), and P4 (Marrakech) in 2018 and 2019. The seed oil was extracted with hexane and the analysis of the fatty fraction was performed by gas chromatography–mass spectrometry (GC–MS). Results show that the major fatty acids for 2018 and 2019 are linoleic acid (61.48%–61.52%, 52.12%–52.14%, 57.76%–58.15%, 61.33%–61.52%), palmitic acid (15.78%–15.81%, 16.44%–16.45%, 19.11%–18.37%, 20.24%–20.32%), oleic acid (11.03%–11.04%, 8.72%–8.82%, 8.51%–8.61%, 8.41%–8.53%), stearic acid (4.35%–3.14%, 5.40%–5.43%, 3.12%–3.13%, 0.96%–1.56%), and cerotic acid (0.62%–0.53%, 4.51%–4.52%, 4.03%–4.06%, 3.84%–3.87%). The unsaturated fatty acids (69.39% in 2018 and 69.68% in 2019) are the most dominant in the four seed extracts compared to the saturated fatty acids. In addition, the oil carob seeds analysis revealed the presence of γ-tocopherol, α-tocopherol and four sterols that included campesterol, stigmasterol, and β-sitosterol. Moreover, the determination of hydrocarbon and un-oxygenated compounds confirmed the existence of major compounds such as heptadecane, 2-methyltriacontane, 1-iodo hexadecane and 1-iodo octadecane. The hierarchical analysis based on the morphological and chromatographic characterization of the seeds allowed the identification of three groups. Consequently, the first group consisted of populations from Marrakesh (P4) and Khemisset (P3), the second group consisted of the P1 from Meknes, and the P2 from Fez constituted the third group. 相似文献
9.
Carl Thodesen Khaldoun Shatanawi Serji Amirkhanian William Bridges 《Construction and Building Materials》2009,23(5):1922-1927
This paper describes the development of an empirical model which may be used for predicting the G*/sin δ for neat and crumb rubber modified (CRM) binders. The model was developed using 36 unique CRM binder combinations, crumb rubber concentrations were varied at 5% intervals between 5% and 20%. The effects of crumb rubber particle size on model accuracy were also studied, ultimately a model was produced with the capability of predicting G*/sin δ values over a range of temperatures and crumb rubber concentrations. By definition, the upper limit of the performance grade is dependent on the G*/sin δ value; therefore, the relationship was also considered in terms of high end failure temperature.The rubber coefficient for G*/sin δ (Rcg) was identified as an important parameter in the estimation of G*/sin δ in addition to the CRM. This term is a quantitative representation of the increase typically witnessed in G*/sin δ values with the addition of CRM. Ambient ground CRM exhibited higher Rcg values than cryogenically ground particles. Additionally, 95% confidence intervals were generated for the predictive model, thus providing a range of accuracy for the model. The resulting confidence intervals were approximately ±1300 Pa, these confidence intervals were seen to capture 92.6% of the 462 data points used. Findings from this research suggest that the differences between cryogenic and ambient CRM binder are accurately described using the Rcg, furthermore binder properties may be predicted using an empirical equation. 相似文献
10.
The effect of nonlinearity in the extrafascicular field in tripolar electrode cuffs on interference pick-up was investigated. It was concluded that the interference is sensitive to electrode separation, especially in short cuffs. This suggests that significant improvements can be obtained by placing the end electrodes a few mm from the cuff ends. 相似文献