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Chinese Chemical Letters 2012年第4期23卷 411-414页

作者： afaf m.abdel hameed Chemistry Department Faculty of ScienceMinia University

Azidation of aminothiophene derivative 1 afforded the corresponding azido derivative *** latter reacted with triphenylphosphine to afford iminophosphorane derivatives *** 3 with phenylisocyanate gave the highly reactive carbodiimide intermediate 4,which was reacted with different nitrones to afford new l,2,4-oxadiazolidin-5-ylidene-aminothiophenes 5a-c. Treatment of 4 with absolute EtOH at room temperature gave methyleneamino-5-（methylthio）thiophene 7,（methylthio）-3-（3- phenylureidothiophene）-2-carboxylate 8 or thienopyrimidine 9 and 10 at refluxing *** reaction of carbodiimide intermediate 4 with different secondary amines gave the new thienopyrimidines 11a-c.

关键词： Carbodiimide Cycloaddition 1 2 4-Oxadiazolidin-5-ylideneaminothiophene derivatives Thienopynmidine Aza-Wittig reaction

Solar thermochemical reactionsⅢ:A convenient one-pot synthesis of 1,2,4,5-tetrasubstituted imidazoles catalyzed by high surface area SiO_2 and induced by solar thermal energy

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Chinese Chemical Letters 2009年第7期20卷 812-814页

作者： Ramadan A.mekheimer afaf m.abdel hameed Seham A.A.mansour Kamal Usef Sadek Chemistry Department Faculty of ScienceEl-Minia UniversityEl-Minia 61519 Egypt Chemistry Department Faculty ofScienceEl-Minia UniversityEl-Minia 61519 Egypt

A simple, convenient and efficient method for the synthesis of 1,2,4,5-tetrasubstituted imidazole derivatives using benzoin, an aromatic aldehyde, an aromatic amine in the presence of ammonium acetate catalyzed by high surface area SiO2 and induced by free solar thermal energy was reported. C 2009 Kamal User Sadek. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： One-pot synthesis SiO2 Solar thermal energy Tetrasubstituted imidazole

The Influence of Tartaric Acid in the Silver Nanoparticle Synthesis Using Response Surface methodology

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Journal of Renewable materials 2024年第2期12卷 245-258页

作者： Yatim Lailun Ni’mah afaf Baktir Dewi Santosaningsih Suprapto Suprapto Chemistry Department Faculty of Science and Data AnalyticsInstitut Teknologi Sepuluh NopemberSurabayaIndonesia Chemistry Department Faculty of Science and TechnologyAirlangga UniversitySurabayaIndonesia Department Clinical microbiology Faculty of MedicineBrawijaya UniversityMalangIndonesia

Silver nanoparticles(AgNPs)synthesized using tartaric acid as a capping agent have a great impact on the reaction kinetics and contribute significantly to the stability of *** protective layer formed by tartaric acid is an important factor that protects the silver surface and reduces potential cytotoxicity *** attributes are critical for assessing the compatibility of AgNPs with biological systems and making them suitable for drug delivery *** aim of this research is to conduct a comprehensive study of the effect of tartaric acid concentration,sonication time and temperature on the formation of silver *** Response Surface methodology(RSm)with Face-Centered Central Composite Design(FCCD),the optimization process identifies the most favorable synthesis ***-Vis spectrum regression analysis shows that AgNPs stabilized with tartaric acid are more stable than AgNPs without tartaric *** highlights the increased stability that tartaric acid provides in AgNP *** size distribution analysis showed a multimodal distribution for AgNPs with tartaric acid and showed the smallest size peak with an average size of 20.53 *** second peak with increasing intensity shows a dominant average size of 108.8 nm accompanied by one standard deviation of 4.225 nm and a zeta potential of−11.08 *** contrast,AgNPs synthesized with polyvinylpyrrolidone(PVP)showed a unimodal particle distribution with an average particle size of 81.62 nm and a zeta potential of−2.96 *** more negative zeta potential of AgNP-tartaric acid indicates its increased *** of antibacterial activity showed that AgNPs stabilized with tartaric acid showed better performance against *** and *** bacteria compared with *** summary,this study highlights the potential of tartaric acid in AgNP synthesis and suggests an avenue for the development of stable AgNPs with versatile applications.

关键词： Tartaric acid silver nanoparticle polyvinyl pyrrolidone response surface methodology

The role of polymorphic cytochrome P450 gene(CYP2B6)in B-chronic lymphocytic leukemia(B-CLL)incidence and outcome among Egyptian patients

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Oncology Research 2024年第4期32卷 785-797页

作者： mENNA AL-ADL mAGDY mYOUSSEF AHmED EL-SEBAIE SHERIF REFAAT afaf EL-SAID Division of Biochemistry Department of ChemistryFaculty of ScienceMansoura UniversityMansoura35511Egypt Hematology Unit Department of Clinical PathologyFaculty of MedicineMansoura UniversityMansoura35511Egypt medical Oncology Unit Oncology Center Mansoura UniversityMansoura35511Egypt Department of Genetics Mansoura University Children’s HospitalMansoura35511Egypt

Cytochromes P450(CYPs)play a prominent role in catalyzing phase I xenobiotic biotransformation and account for about 75%of the total metabolism of commercially available drugs,including *** gene expression and enzyme activity of CYPs are variable between individuals,which subsequently leads to different patterns of susceptibility to carcinogenesis by genotoxic xenobiotics,as well as differences in the efficacy and toxicity of clinically used *** research aimed to examine the presence of the CYP2B6*9 polymorphism and its possible association with the incidence of B-CLL in Egyptian patients,as well as the clinical outcome after receiving cyclophosphamide *** was isolated from whole blood samples of 100 de novo B-CLL cases and also from 100 sex-and age-matched healthy *** presence of the CYP2B6*9(G516T)polymorphism was examined by PCR-based allele specific amplification(ASA).Patients were further indicated for receiving chemotherapy,and then they were followed *** CYP2B6*9 variant indicated a statistically significant higher risk of B-CLL under different genetic models,comprising allelic(T-allele vs.G-allele,OR=4.8,pminant(GT+TT ***,OR=5.4,pmide chemotherapy,we found that the patients with variant genotypes(GT+TT)were less likely to achieve remission compared to those with the wild-type genotype(GG),with a response percentage of(37.5%vs.83%,respectively).In conclusion,our findings showed that the CYP2B6*9(G516T)polymorphism is associated with B-CLL susceptibility among Egyptian *** variant greatly affected the clinical outcome and can serve as a good therapeutic marker in predicting response to cyclophosphamide treatment.

关键词： B-CLL Xenobiotics Cytochromes P450 CYP2B6

Pediatric and adult liver transplantation in Bahrain: The experiences in a country with no available liver transplant facilities

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World Journal of Transplantation 2024年第1期14卷 96-111页

作者： Hasan m Isa Fatema A Alkharsi Jawad K Khamis Sawsan A Hasan Zainab A Naser Zainab N mohamed afaf m mohamed Shaikha A Altamimi Department of Pediatrics Salmaniya Medical ComplexManama 26671Bahrain Department of Pediatrics Arabian Gulf UniversityManama 26671Bahrain Department of medicine Salmaniya Medical ComplexManama 26671Bahrain Public Health Directorate Ministry of HealthManama 26671Bahrain The Overseas Office Supreme Committee for Treatment AbroadMinistry of HealthManama 26671Bahrain

BACKGROUND Liver transplantation(LT)is a life-saving procedure for patients with end-stage liver disease and has become the standard and most effective treatment method for these *** are many indications for LT that vary between countries and *** outcome of LT depends on the available facilities and surgical expertise,as well as the types of liver graft donors *** To assess the clinical characteristics of patients from Bahrain who underwent LT overseas,and analyze factors affecting their *** In this retrospective cohort study,we reviewed the medical records and overseas committee registry information of all pediatric and adult patients who were sent overseas to undergo LT by the Pediatric and medical Departments of Salmaniya medical Complex and Bahrain Defence Force Hospital via the Overseas Treatment Office,ministry of Health,Kingdom of Bahrain,between 1997 and *** data,LT indication,donor-recipient relationship,overseas LT center,graft type,post-LT medications,and LT complications,were *** measured included the overall and 5-year LT survival ***’s exact,Pearsonχ2,and mann-Whitney U tests were used to compare the pediatric and the adults’group in terms of clinical characteristics,donor-recipient relationship,medication,complications,and *** analysis was estimated via the Kaplan-meier’s *** and multivariate analyses were used to detect predictors of *** Of the 208 eligible patients,170(81.7%)were sent overseas to undergo LT while 38(18.3%)remained on the waiting *** the 170 patients,167(80.3%)underwent LT and were included in the *** majority of the patients were Bahraini(91.0%),and most were males(57.5%).One-hundred-and-twenty(71.8%)were adults and 47(28.3%)were *** median age at transplant was 50.0[interquartile range(IQR):14.9–58.4]*** main indication for pediatric LT was biliary atresia(31.9%),while that of adult LT was

关键词： Overseas liver transplantation End-stage liver disease Liver transplant facilities Liver donor Biliary atresia Hepatitis C

Adherence to Advisory Committee on Immunization Practices in diabetes mellitus patients in Saudi Arabia:A multicenter retrospective study

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World Journal of Diabetes 2024年第3期15卷 440-454页

作者： Saleh Fahad Alqifari Aya K Esmail Dalal m Alarifi Ghalya Y Alsuliman maram m Alhati may R mutlaq mohammed Aldhaeefi Shaden A Alshuaibi Palanisamy Amirthalingam Abrar Abdallah afaf S Wasel Heba R Hamad Shoroq Alamin Tasneem H Atia Tariq Alqahtani Department of Pharmacy Practice University of TabukTabuk 71491Saudi Arabia Department of Clinical Sciences Sulaiman Alrajhi UniversityQassim 52726Saudi Arabia Department of Family medicine International Medical CenterJeddah 23214Saudi Arabia Clinical and Administrative Pharmacy Sciences College of PharmacyHoward UniversityWashingtonDC 20059United States Department of Pharmacology King Saud Bin Abdulaziz University for Health SciencesKing Abdullah International Medical Research CenterRiyadh 11481Saudi Arabia

BACKGROUND Patients with diabetes mellitus(Dm)are predisposed to an increased risk of infection signifying the importance of vaccination to protect against its potentially severe *** Centers for Disease Control and Prevention/Advisory Committee on Immunization Practices(CDC/ACIP)issued immunization recommendations to protect this patient *** To assess the adherence of patients with Dm to the CDC/ACIP immunization recommendations in Saudi Arabia and to identify the factors associated with the vaccine adherence *** An observational retrospective study conducted in 2023 was used to collect data on the vaccination records from 13 diabetes care centers in Saudi Arabia with 1000 eligible patients in phase I with data collected through chart review and 709 patients in phase II through online *** Among participants,10.01%(n=71)had never received any vaccine,while 85.89%(n=609)received at least one dose of the coronavirus disease 2019(COVID-19)vaccine,and 34.83%(n=247)had received the annual influenza *** 2.96%(n=21),2.11%(n=15),and 1.12%(n=8)received herpes zoster,tetanus,diphtheria,and pertussis(Tdap),and human papillomavirus(HPV)vaccines,*** patients with Dm in Saudi Arabia,the rate of vaccination for annual influenza and COVID-19 vaccines was higher compared to other vaccinations such as herpes zoster,Tdap,pneumococcal,and *** such as vaccine recommendations provided by family physicians or specialists,site of care,income level,Dm-related hospitalization history,residency site,hemoglobin A1c(HbA1c)level,and health sector type can significantly influence the vaccination rate in patients with *** non-vaccinated patients with Dm,the most reported barriers were lack of knowledge and fear of side *** signifies the need for large-scale research in this area to identify additional factors that might facilitate adherence to CDC/ACIP vaccine recommendations in patients with *** In S

关键词： Diabetes mellitus Vaccine recommendation COVID-19 vaccine Influenza vaccine Pneumococcal vaccine Immunization Retrospective study

A New Navigation Force model for the Earth’s Albedo and Its Effects on the Orbital motion of an Artificial Satellite

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Applied mathematics 2011年第7期2卷 801-807页

作者： Yehia A. abdel-Aziz afaf m. abdel-hameed Khalil I. Khalil 不详

In this paper, we developed a new approach of an analytical model to calculate the radial and transversal components of the acceleration due to the effects of Earth’s albedo. Its effects on the orbital motion of an artificial satellite are introduced. It is assumed that the satellite’s horizon is illuminated and the sun lies on the equator. The magnitudes of those components are obtained and their effects on orbital evolution have been tested for different satellites elements. The perturbations in orbital elements due to Earth’s albedo have been obtained using Lagrange Planetary equation in Gaussian form, in particular the case of LAGEOS satellite, have been found using this new analytical formalism.

关键词： Satellite Dynamics Non-Gravitational Forces Albedo Effect Orbital Perturbations Lagrange Planetary Equations

Anodic Coating Characteristics of Different Aluminum Alloys for Spacecraft materials Applications

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materials Sciences and Applications 2017年第2期8卷 197-208页

作者： afaf m. Abd El-hameed Yehia A. abdel-Aziz Fatma S. El-Tokhy National Research Institute of Astronomy and Geophysics (NRIAG) Cairo Egypt Faculty of Engineering El-Zagazig University Zagazig Egypt

Anodic oxide coatings on aluminum alloys are used for space environment applications. These provide specific thermo-optical properties to spacecraft surface. Fragments of these coatings lead to generate the contamination in satellites and affect the mission lifetime. The current work concerns studying of the anodic processes applied on aluminum and different groups of aluminum alloys as Al7075, Al2024 and Al6061. Experimental procedures are performed using sulfuric acid at different values of current density (1 - 2 A/dm2). The influence of the parameters of anodic film formation on the coating characteristics and layer thickness of aluminum alloys has been investigated. Reflectance and optical properties of the anodized aluminum alloy coatings are determined and found to be dependent on the alloying elements. Changes in anodic coating weight and film thickness of aluminium alloys with the process parameters as current density, temperature, time duration, acid concentration, and sealing system have been studied. moreover, morphology and surface structure of the considered samples are carried out in attempt to understand the physical characteristics. The obtained results are compared and briefly outlined.

关键词： Anodic Oxide Coatings Aluminum Alloy Samples Sulfuric Acid Optical Properties morphology Analysis

Development of micro/nanostructured‒based biomaterials with biomedical applications

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BIOCELL 2023年第8期47卷 1743-1755页

作者： afaf ALHARTHI Department of Clinical Laboratory Sciences College of Applied Medical SciencesTaif UniversityTaif21944Saudi Arabia

Natural biomaterials are now frequently used to build biocarrier systems,which can carry medications and biomolecules to a target region and achieve a desired therapeutic *** and polymers are of great importance in the synthesis of *** recent studies have tended to use these materials because they are easily obtained from natural sources such as fungi,algae,bacteria,and medicinal *** are also biodegradable,compatible with neighborhoods,and *** biomaterials and polymers are chemically changed when they are linked by cross linking agents with other polymers to create scaffolds,matrices,composites,and interpenetrating polymer networks employing microtechnology and *** review highlights how microengineered and nanoengineered biomaterials are utilized to produce efficient drug-delivery systems and biomedical and biological therapies and how innovative sources of biomaterials have been identified.

关键词： micro/Nanoparticles Biomaterials Green synthesis microorganisms Algae medicinal plants

Inter-population variabilities in seed mass and germination of Panicum turgidum and Pennisetum divisum in the desert of Kuwait

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Journal of Arid Land 2020年第1期12卷 144-153页

作者： Arvind BHATT Narayana R BHAT afaf AL-NASSER maría m CARÓN AndreaSANTO Kuwait Institute for Scientific Research Safat 24885Kuwait Laboratory of Botanical Research(LABIBO) Faculty of Natural SciencesNational University of Salta-CONICETSalta 4400Argentina Independent Researcher Selargius 09047Italy

Understanding variability in seed germination among populations is essential for planning an effective germplasm collection for restoration and conservation *** knowledge of germination and dormancy patterns among populations of desert grasses is crucial for determining the potential of the species and populations to be used for restoration and conservation as well as forage *** in seed germination of Panicum turgidum Forssk and Pennisetum divisum(Gmel.)*** the desert of Kuwait was evaluated in different populations in may *** of seed germination(25 seeds and 4 replicates)was conducted for each population at night/day temperatures of 15℃/20℃and 20℃/30℃under the following light condition:continuous darkness or 12 h/12 h light/*** showed that seed masses of both species strongly varied according to their seed provenances,and both species produced heavier seeds in population with a higher soil electrical *** germination percentage considerably varied between two species,and the variation in *** was greater(17%–49%)than that of ***(72%–93%).Germination percentage in *** was greater at high temperature(20℃/30℃)than at low temperature(15℃/20℃).However,temperature regimes had no effect on germination percentage of *** *** germination time of both species exhibited significant inter-population *** result is especially relevant to assure the selection of the best population of each species and the regeneration success of the *** this,inter-population variability also provides valuable information for enhancing our understanding of the mechanisms that regulate seed germination and how they might be related to seed provenance.

关键词： desert grass seed germination inter-population variability seed provenance seed dormancy