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      • KCI등재

        Attempts to enhance the anti-cancer activity of curcumin as a magical oncological agent using transdermal delivery

        Abdel-Hafez Salma M.,Hathout Rania M.,Sammour Omaima A. 경희대학교 융합한의과학연구소 2021 Oriental Pharmacy and Experimental Medicine Vol.21 No.1

        For the past few years, curcumin has drawn the attention of scientists in multidisciplinary fields related to oncology and therapeutics. However, despite its high potency, its delivery suffers from several limitations and challenges that hinders the complete benefit from this magical molecule. Accordingly, this review demonstrates the several attempts and endeavors that the scientists exerted in order to delivery this molecule successfully through the transdermal route. We believe that the transdermal route of delivery of drugs can pose a new platform of targeting solid tumors such as the breast carcinoma so that applying a transdermal patch over the skin or the membrane covering the solid tumor can provide a means of the cure.

      • KCI등재

        Benzimidazole Condensed Ring Systems: New Synthesis and Antineoplastic Activity of Substituted 3,4-Dihydro-and 1,2,3,4-Tetrahydro-benzo[4,5]imidazo[1,2-a]pyrimi dine Derivatives

        Abdel-hafez, Atef Abdel-monem 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.6

        As part of an ongoing effort to develop new antineoplastic agents, a series of substituted 3,4-dihydro- and 1,2,3,4-tetrahydro-benzo[4,5]imidazo[1,2-a]pyrimidine derivatives (5-19) were synthesized. 1,2,3,4-Tetrahydrobenzo[4,5]imidazo[1,2-a]pyrimidine-2-one derivatives (5-7) were prepared via one-pot two-component thermal cyclization reaction of 2-aminobenzimidazole 1 and P-substituted methyl cinnamates (2-4). Vilsmir-Haack formylation of these derivatives (5-7) afforded the 2-chloro-3-carboxaldehyde targets (8-10) followed by nucleophilic displacement of the chloro atom in the 3-carboxaldehyde compounds (8-10) to yield the remaining final targets(11-19). The structures of the synthesized derivatives (5-19) were confirmed by means of IR, $^1$H NMR, MS and elemental analyses. The synthesized derivatives (5-19) were subjected to the National Cancer Institute (NCI) in vitro disease human cell screening panel assay. 2-chloro-4-phenyl-3,4-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxyaldehyde (8, NCl722731) and 4-(4-methoxyphenyl)-2-(4-methylpiperazin-1-yl)-3,4-dihydrobenzo[4,5]imidazo(1,2-a)pyrimidine-3-carboxaldehyde (18, NCI 722739) showed a variable degree of antineoplastic activity against some of the cell lines tested. 2-Chloro-4-(4-nitrophenyl)-3,4-dihy-drobenzo[4,5]imidazo[1,2-a)pyrimidine-3-carboxyaldehyde (10, NCI 722743) exhibited good in vitro antineoplastic activity with subpanel disease selectivity against all the cell lines tested with log$_{10}$ GI$_{50}$ (M), the concentration that inhibits 50% of cell growth, values ranging from -5.08 to <-8.00.

      • SCIESCOPUSKCI등재

        Synthesis and Anticonvulsant Evaluation of N-Substituted-Isoindolinedione Derivatives

        Abdel-Hafez, Atef Abdel-Monem The Pharmaceutical Society of Korea 2004 Archives of Pharmacal Research Vol.27 No.5

        A series of N-substituted-1,3-isoindolinedione derivatives (2-16) were synthesized for the purpose of defining the effect of N-substitution on the anticonvulsant activity of these derivatives. The target compounds (2-16) were obtained by condensation of phthalic anhydride with the corresponding amine derivative. The structures of the synthesized derivatives (2-16) were confirmed by means of IR, $^1$H-NMR, $^{13}$ C-NMR, MS and elemental analyses. The anticonvulsant activity of all compounds (2-16) were evaluated by subcutaneous pentylenetetrazole seizure threshold test at doses of 0.2, 0.4 and 0.8 mmol/kg compared with sodium valproate as a positive control. Their neurotoxicity were determined by the rotorod test. Many of the present series of compounds showed good anticonvulsant activity at the tested doses, as compared to sodium valproate. Three of them (4, 6 and 11) exhibited 100 % protection against convulsions, neurotoxicity and death at all tested doses. Out of the series, two compounds (12 and 13) were completely inactive with 100% mortality. 3-(p-chlorophenyl)-4-(1 ,3-dioxo-2,3-dihydro-1 H-2-isoindolyl) butanoic acid derivative (11) has emerged as the most active compound which is 20 times more active than valproate with ED$_{50}$ 8.7, 169 mg/kg; TD$_{50}$ 413, 406 mg/kg and PI 47.5, 2.4. The results revealed the importance of the combination of baclofenic and phthalimide moieties (compound 11) as a promising anticonvulsant candidate.

      • KCI등재

        Synthesis and Anticonvulsant Evaluation of N-Substituted-Isoindolinedione Derivatives

        Atef Abdel-Monem Abdel-Hafez 대한약학회 2004 Archives of Pharmacal Research Vol.27 No.5

        A series of N-substituted-1,3-isoindolinedione derivatives (2-16) were synthesized for the purpose of defining the effect of N-substitution on the anticonvulsant activity of these derivatives. The target compounds (2-16) were obtained by condensation of phthalic anhydride with the corresponding amine derivative. The structures of the synthesized derivatives (2-16) were confirmed by means of IR, 1H-NMR, 13C-NMR, MS and elemental analyses. The anticonvulsant activity of all compounds (2-16) were evaluated by subcutaneous pentylenetetrazole seizure threshold test at doses of 0.2, 0.4 and 0.8 mmol/kg compared with sodium valproate as a positive control.Their neurotoxicity were determined by the rotorod test. Many of the present series of compounds showed good anticonvulsant activity at the tested doses, as compared to sodium valproate. Three of them (4, 6 and 11) exhibited 100 % protection against convulsions, neurotoxicity and death at all tested doses. Out of the series, two compounds (12 and 13) were completely inactive with 100% mortality. 3-(p-chlorophenyl)-4-(1,3-dioxo-2,3-dihydro-1H- 2-isoindolyl)butanoic acid derivative (11) has emerged as the most active compound which is 20 times more active than valproate with ED50 8.7, 169 mg/kg; TD50 413, 406 mg/kg and PI 47.5, 2.4. The results revealed the importance of the combination of baclofenic and phthalimide moieties (compound 11) as a promising anticonvulsant candidate.

      • KCI등재

        Benzimidazole Condensed Ring Systems: New Synthesis and Antineoplastic Activity of Substituted 3,4-Dihydro- and 1,2,3,4-Tetrahydro-benzo[4,5]imidazo[1,2-a]pyrimidine Derivatives

        Atef Abdel-monem Abdel-hafez 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.6

        As part of an ongoing effort to develop new antineoplastic agents, a series of substituted 3,4- dihydro- and 1,2,3,4-tetrahydro-benzo[4,5]imidazo[1,2-a]pyrimidine derivatives (5-19) were synthesized. 1,2,3,4-Tetrahydrobenzo[4,5]imidazo[1,2-a]pyrimidine-2-one derivatives (5-7) were prepared via one-pot two-component thermal cyclization reaction of 2-aminobenzimidazole 1 and P-substituted methyl cinnamates (2-4). Vilsmir-Haack formylation of these derivatives (5-7) afforded the 2-chloro-3-carboxaldehyde targets (8-10) followed by nucleophilic displacement of the chloro atom in the 3-carboxaldehyde compounds (8-10) to yield the remaining final targets (11-19). The structures of the synthesized derivatives (5-19) were confirmed by means of IR, 1H NMR, MS and elemental analyses. The synthesized derivatives (5-19) were subjected to the National Cancer Institute (NCI) in vitro disease human cell screening panel assay. 2- Chloro-4-phenyl-3,4-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxyaldehyde (8, NCI 722731) and 4-(4-methoxyphenyl)-2-(4-methylpiperazin-1-yl)-3,4-dihydrobenzo[4,5]imidazo [1,2-a]pyrimidine-3-carboxaldehyde (18, NCI 722739) showed a variable degree of antineoplastic activity against some of the cell lines tested. 2-Chloro-4-(4-nitrophenyl)-3,4-dihydrobenzo[ 4,5]imidazo[1,2-a]pyrimidine-3-carboxyaldehyde (10, NCI 722743) exhibited good in vitro antineoplastic activity with subpanel disease selectivity against all the cell lines tested with log10 GI50 (M), the concentration that inhibits 50% of cell growth, values ranging from –5.08 to < -8.00.

      • KCI등재후보

        Performance of M-ary PPM UWB Radio in Fading Channels

        Mohammed, Abdel-Hafez,Alagoz, Fatih,Hamalainen, Matti The Korea Institute of Information and Commucation 2003 Journal of communications and networks Vol.5 No.4

        This paper investigates the performance of M-ary pulse position modulation (PPM) multiuser ultra-wideband (UWB) communication systems in terms of symbol error rate (SER) over fading and additive white Gaussian noise (AWGN) channel. Based on Gaussian approximation for the multiple access interference, an expression for the signal-to-noise ratio (SNR) is derived for the UWB system. This expression is used to derive exact SER expressions for coherent UWB receivers. The effect of pulse selection on the SER of multiuser UWB system is studied. In addition to rectangular pulse, the 2nd derivative Gaussian waveform and Rayleigh pulses were considered. We show that the system capacity and/or SER performance can be significantly increased by using the monocycle pulse in fading channels.

      • KCI등재

        Performance Improvement of the Wald Test for GPS RTK with the Assistance of INS

        Mamoun F. Abdel-Hafez,Dae Je Kim,Eunsung Lee,Sebum Chun,Young Jae Lee,Taesam Kang,Sangkyung Sung 대한전기학회 2008 International Journal of Control, Automation, and Vol.6 No.4

        To use the Global Positioning System (GPS) carrier phase measurement for precise positioning, the integer ambiguities at the early stage of most algorithms must be determined. Furthermore, if a precise positioning is to be applied to real time navigation, fast determination and validation methods for integer ambiguity are essential. In this paper, the Wald test that simultaneously determines and validates integer ambiguities is used with assistance of the Inertial Navigation System (INS) to improve its performance. As the Wald test proceeds, it assigns a higher probability to the candidate that is considered to be true at each time step. The INS information is added during the Wald test process. Large performance improvements were achieved in convergence time as well as in requiring fewer observable GPS satellites. To test the performance improvement of the Wald test with the INS information, experimental tests were conducted using a ground vehicle. The vehicle moved in a prescribed trajectory and observed seven GPS satellites. To verify the effect of the INS information on the Wald test, the convergence times were compared with cases that considered the INS information and cases that did not consider the INS information. The results show that the benefits of using the INS were emphasized as fewer GPS satellites were observable. The performance improvement obtained by the proposed algorithm was shown through the fast convergence to the true hypothesis when using the INS measurements.

      • Novel approach to improve nano green mortar behaviour using nano-paper waste with nano-metakaolin

        Radwa Defalla Abdel, Hafez,Bassam A., Tayeh,Raghda Osama Abd-Al, Ftah,Khaled, Abdelsamie Techno-Press 2022 Advances in concrete construction Vol.14 No.5

        Treatment of solid waste building materials is a crucial method of disposal and an area of ongoing research. New standards for the treatment of solid waste building materials are necessary due to multisource features, huge quantities, and complicated compositions of solid waste. In this research, sustainable nanomaterial mixtures containing nano-paper waste (NPW) and nano-metakaolin (NMK) were used as a substitute for Portland cement. Portland cement was replaced with different ratios of NPW and NMK (0%, 4%, 8%, and 12% by weight of cement) while the cement-to-water ratio remained constant at 0.4 in all mortar mixtures. The fresh properties had a positive effect on them, and with the increase in the percentage of replacement, the fresh properties decreased. The results of compressive strength at 7 and 28 days and flexural strength at 28 days show that the nanomaterials improved the strength, but the results of NMK were better than those of NPW. The best replacement rate was 8%, followed by 4%, and finally 12% for both materials. The combination of NMK and NPW as a replacement (12% NMK + 12% NPW) showed less shrinkage than the others because of the high pozzolanic reactivity of the nanomaterials. The combination of NMK and NPW improved the microstructure by increasing the hydration volume and lowering the water in the cement matrix, as clearly observed in the C-S-H decomposition.

      • KCI등재

        Building a Robust Integrity Monitoring Algorithm for a Low Cost GPS-aided-INS System

        Mamoun F. Abdel-Hafez,Tariq S. Abuhashim,Mohammad Ameen Al-Jarrah 제어·로봇·시스템학회 2010 International Journal of Control, Automation, and Vol.8 No.5

        In this paper, the integrity of low cost GPS/INS systems is investigated to ensure the ability to obtain continuous high-integrity, high-accuracy vehicle state estimate under low-computational system requirement. The utilization of two fault detection and identification (FDI) techniques, the (or sometimes referred to as chi-squared) gating function and the multiple model adaptive estimation (MMAE), is proposed to monitor the integrity of GPS measurements. A fault in GPS measurements is modeled with an increase in GPS measurements noise covariance matrix which may result from mis-tuning of filter’s noise parameters, interference, jamming, or multipath errors. These types of faults are covered by this work and are assumed to last for unconstrained period of time. FDI systems are computationally very inexpensive, have good fault detection ability and require no a priori knowledge on system dynamics. However, they are sensitive to filter tuning and fail to detect faults when the filter converges to them rather than rejecting them. Model-based approaches provide outstanding FDI ability. However, they are computationally demanding, require a priori knowledge on system model, sensitive to mismodeling errors, have finite convergence time, and compromise filter optimality under no-failure conditions. The proposed fusion algorithm guarantees integrity and does not affect filter’s optimality under no-failure conditions. Simulated and experimental tests were conducted to verify the accuracy of the proposed techniques. Results are presented at the end of the paper to highlight the performance characteristics of the proposed FDI system implementation.

      • KCI등재

        Effect of nicotine on the structure of cochlea of guinea pigs

        Amel M M Abdel Hafez,Sanaa A M Elgayar,Ola A Husain,Huda S A Thabet 대한해부학회 2014 Anatomy & Cell Biology Vol.47 No.3

        Smoking has been positively associated with hearing loss in human. However, its effect on the cochlea has not been previously evaluated. Aim of work is to investigate the effect of nicotine, which is the primary pharmacological component of tobacco, on the structure of the cochlea of adult male guinea pigs. Fifteen male guinea pigs were classified into two groups: group I (control) and group II (nicotine treated group). Group II was further subdivided into two subgroups; IIA and IIB according to the dose of nicotine (3 mg/kg and 6 mg/kg, respectively). The cochlea was harvested and processed for light microscopy, transmission electron microscopy and scanning electron microscopy. Nicotine administration induced damage of outer hair cells which were distorted in shape with vacuolated cytoplasm and heterochromatic nuclei. Topography revealed damage of the stereocilia which included disorganization, bent and limp or complete loss and expansion of the surrounding supporting cells. These changes were more pronounced in the basal turn of the cochlea and mainly involved the outer hair cells. High dose induced more damage and resulted in protrusion of the apical poles of hair cells (blebing), particularly the outer two rows. Nicotine is proved to be harmful to the cells of the cochlea, particularly the outer hair cells of the basal turn. High doses induce blebing of hair cells.

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