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101.
Abdelhakim Bouyahya Aicha El Allam Ikrame Zeouk Douae Taha Gokhan Zengin Bey Hing Goh Michelina Catauro Domenico Montesano Nasreddine El Omari 《Molecules (Basel, Switzerland)》2022,27(1)
Grifolin is a volatile compound contained in essential oils of several medicinal plants. Several studies show that this substance has been the subject of numerous pharmacological investigations, which have yielded interesting results. Grifolin demonstrated beneficial effects for health via its multiple pharmacological activities. It has anti-microbial properties against bacteria, fungi, and parasites. In addition, grifolin exhibited remarkable anti-cancer effects on different human cancer cells. The anticancer action of this molecule is related to its ability to act at cellular and molecular levels on different checkpoints controlling the signaling pathways of human cancer cell lines. Grifolin can induce apoptosis, cell cycle arrest, autophagy, and senescence in these cells. Despite its major pharmacological properties, grifolin has only been investigated in vitro and in vivo. Therefore, further investigations concerning pharmacodynamic and pharmacokinetic tests are required for any possible pharmaceutical application of this substance. Moreover, toxicological tests and other investigations involving humans as a study model are required to validate the safety and clinical applications of grifolin. 相似文献
102.
Till?R?hrich Bassam Abu?Thaher Hans-Hartwig?OttoEmail author 《Monatshefte für Chemie / Chemical Monthly》2004,135(1):55-68
Summary. 1,2-Thiazetidine-3-acetic acid 1,1-dioxide was N-alkylated using bromoacetates, and N-acylated using either acyl chlorides, protected amino acid fluorides, or N-protected amino acid NCA, which seemed to be the most universal method. Most of the obtained -sultam peptides were sensitive against humidity, they hydrolyzed forming sulfonic acids, and reactions with amines resulted in sulfonamides. Reactions of N-acylated products showed that the sulfonyl group was faster attacked than the imide structure. 相似文献
103.
Bassam A. Abu Thaher Jalal A. Zahra Mustafa M. El‐Abadelah 《Journal of heterocyclic chemistry》2002,39(5):901-904
2‐Aminobenzoic acid reacts readily, in the presence of triethylamine, with hydrazonoyl chlorides ( 5a‐c ) (precursors of the reactive nitrile imine 1,3‐dipolar species) to afford high yields of the corresponding acyclic amidrazone adducts ( 6a‐c ). The latter adducts undergo, in THF in presence of 1,1‐carbonyldiimida‐zole, smooth intramolecular cyclization involving the activated carboxyl and the NH‐ termini to deliver unequivocally the respective dihydro‐1,3,4‐benzotriazepin‐5‐ones ( 7a‐c ). 相似文献
104.
105.
Aissa Aibeche Nasreddine Amroune Stephane Maingot 《Mediterranean Journal of Mathematics》2016,13(3):1051-1063
In this work, we give new results concerning existence, uniqueness and maximal regularity of the strict solution of a class of elliptic equations with non-local boundary conditions containing an unbounded linear operator. This study is performed in the framework of UMD Banach spaces. 相似文献
106.
We analyze a problem which describes the frictional contact between a thermoviscoelastic body and a rigid foundation. The process is assumed to be quasistatic and the contact is modeled by a general normal damped response condition with friction law and heat exchange. Then we present a variational formulation of the problem, which is set in an abstract form as a system of evolution equations for the displacements and temperature. We establish the existence and uniqueness of the weak solution, using general results on evolution equations with monotone operators and fixed point arguments. Finally, we study the continuous dependence of the solution with respect to the initial data and contact conditions. 相似文献
107.
Guerrero J Salcudean SE McEwen JA Masri BA Nicolaou S 《IEEE transactions on bio-medical engineering》2006,53(5):845-854
A system for objective vessel compression assessment for deep venous thrombosis characterization using ultrasound image data and a sensorized ultrasound probe is presented. Two new objective measures calculated from applied force and transverse vessel area are also presented and used to describe vessel compressibility. A modified star-Kalman algorithm is used for feature detection in acquired ultrasound images, and objective measures of vessel compressibility are calculated from the detected features and acquired force and location data from the sensorized probe. A three-dimensional shape model of the examined vessel that includes compressibility measures mapped as colors to its surface is presented on the user interface, as well as a virtual representation of the image plane. The compressibility measures were validated using expert segmentation of healthy and diseased vessels and compared using paired t-tests, which showed a significant difference between healthy and diseased cases for both measures. 100% sensitivity and specificity were obtained for both measures. The system was implemented in real-time (16 Hz) and evaluated using a tissue phantom and on healthy human subjects. Sensitivity was 100% and 60%, while specificity was 97% for both measures when implemented. The initial results for the system and its components are promising. 相似文献
108.
Saad Haj Bakry Bassam Al‐Bassam Abdulmohsen Alheraish 《International Journal of Network Management》2004,14(6):391-403
This paper presents an integrated and simple approach for the analysis of Internet backbone networks, emphasizing the need for a balance between the network resources utilization requirements of the Internet services providers (ISPs) and the services delay constraints of the Internet users (IUs). The integration of the approach is achieved by putting together the various issues associated with the target analysis, including network topology, capacity, traffic load, routing, traffic flow, and performance; and by considering the analysis both at the link level and at the path level. The simplicity of the approach is achieved by eliminating unnecessary details; and by allowing the approach to be applied in easy steps, using an open source, straightforward computer program. A typical example is used to illustrate the practical application of the approach. The work would be useful to the designers and administrators of ISP networks facing the continuous challenge of newer e‐services and higher user traffic. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
109.
110.
Na’il Saleh Abbas Khaleel Hmoud Al-Dmour Bassam al-Hindawi Elena Yakushenko 《Journal of Thermal Analysis and Calorimetry》2013,111(1):385-392
The inclusion complex of cucurbit[7]uril (CB7) and albendazole (ABZ) in solid state was prepared by freeze-drying. The formation of a host–guest complex was confirmed by microanalysis, 1H-nuclear magnetic resonance spectroscopy, and fourier transformed-infrared spectroscopy (FT-IR) techniques. The shifts in the NMR peaks supported the encapsulation from the propylthio and not the carbamate site, in agreement with the previously reported results in solution. The N2 adsorption–desorption isotherms indicated no change in the calculated surface area or the pore size distribution for the unbound and CB7-bound ABZ solid drugs. Freeze-drying produced a system with a higher degree of amorphisation as confirmed by the X-ray powder diffraction (XRD) technique. Thermal analysis of the drug-loaded CB7 by using differential scanning calorimetry and thermogravimetry demonstrated the possibility of dehydration at temperature 100 °C beyond the melting point of unbound ABZ since no melting of the samples was observed until the CB7 itself begins to decompose around 300 °C. Putting it all together, the results supported that CB7 imparts significant thermal/physical stability on the ABZ drug in the solid state. 相似文献