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Chinese Journal of Chemistry 2011年第7期29卷 1473-1482页

作者： Youssef, mohamed salah K. Abbady, mohamed S. Ahmed, Ragaa A. Omar, Ahmed A. Chemistry Department Faculty of Science Assiut University Assiut 71516 Egypt

Ethyl 7-amino-3-（3-methyl-5-oxo- 1-phenyl-2-pyrazolin-4-yl）-5-aryl-5H-thiazolo[3,2-a]pyrimidine-6-carboxy- late was hydrolyzed with an ethanolic sodium hydroxide and the sodium salt thus formed underwent cyclization with acetic anhydride to afford 2-methyl-7-（3-methyl-5-oxo-l-phenyl-2-pyrazolin-4-yl）-5-arylthiazolo[3,2-a]- pyrimido[4,5-d]oxazin-4（SH）-one. This compound was transformed to related heterocyclic systems via its reaction with various reagents. The biological activity of the prepared compounds was tested against Gram positive and Gram negative bacteria as well as yeast-like and filamentous fungi. They revealed in some cases excellent biocidal properties.

关键词： thiazolopyrimidooxazinone thiazolopyrimidopyrimidines antimicrobial activity

Experimental Investigation of the Small-scale Fixed Multi-chamber OWC Device

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Chinese Journal of Mechanical Engineering 2021年第5期34卷 408-421页

作者： Mohammad Shalby Ahmed Elhanafi Paul Walker David G.Dorrell Ahmad salah mohamed R.Gomaa mohamed Behiri Mechanical Engineering Department Faculty of EngineeringAl-Hussein Bin Talal UniversityMa’an 71111Jordan National Centre for Maritime Engineering and Hydrodynamics Australian Maritime CollegeUniversity of TasmaniaLauncestonTAS 7250Australia School of Mechanical and Mechatronic Systems University of Technology SydneySydneyNSW 2007Australia School of Electrical and Information Engineering University of the WitwatersrandDurban 2000South Africa Electrical Engineering Department Faculty of EngineeringAl Hussein Bin Talal UniversityMa’an 71111Jordan Mechanical Engineering Department Benha Faculty of EngineeringBenha UniversityBenha 13518Egypt 不详

Sea wave energy generators or converters(WECs)have the potential to become a viable technology for clean,renewable energy *** the WEC technologies,the oscillating water columns(OWCs)are the most common WEC devices *** have been studied and developed over many ***-chamber oscillating water columns(MC-OWC)have the potential to have a higher energy conversion when extracting energy in mixed sea states than single-chamber *** the work reported in this paper,physical experiments are carried under regular wave conditions to test the wave power extraction of a fixed MC-OWC small-scale *** Power Take-Off(PTO)of the device is simulated using orifice *** flow characteristics through these orifices are pre-calibrated such that the extracted power can be obtained only using the pressure *** condition effects on the damping of the PTO of the device power extraction are *** test results illustrate that the PTO system damping is critical and affects device performance.

关键词： cean wave energy Energy conversion Oscillating water column Multi-chamber OWC

Roscovitine synergizes with conventional chemo-therapeutic drugs to induce efficient apoptosis of human colorectal cancer cells

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World Journal of Gastroenterology 2008年第33期14卷 5162-5175页

作者： mohamed salah I Abaza Abdul-Majeed A Bahman Rajaa J Al-Attiyah Molecular Biology Program Department of Biological Sciences Faculty of Science Kuwait UniversitySafaat 13006 Kuwait Department of Microbiology Faculty of Medicine Kuwait UniversitySafaat 13006 Kuwait

AIM: To examine the ability of cyclin-dependent kinase inhibitor (CDKI) roscovitine (Rosco) to enhance the antitumor effects of conventional chemotherapeutic agents acting by different mechanisms against human colorectal cancer. METHODS: Human colorectal cancer cells were treat-ed, individually and in combination, with Rosco, taxol, 5-Fluorouracil (5-FU), doxorubicine or vinblastine. The antiproliferative effects and the type of interaction of Rosco with tested chemotherapeutic drugs were de-termined. Cell cycle alterations were investigated by fluorescence-activated cell sorter FACS analysis. Apop-tosis was determined by DNA fragmentation assay. RESULTS: Rosco inhibited the proliferation of tumor cells in a time-and dose-dependent manner. The ef-ficacies of all tested chemotherapeutic drugs were markedly enhanced 3.0-8.42 × 103 and 130-5.28 × 103 fold in combination with 5 and 10 μg/mL Rosco, re-spectively. The combination of Rosco and chemothera-peutic drugs inhibited the growth of human colorectal cancer cells in an additive or synergistic fashion, and in a time and dose dependent manner. Rosco induced apoptosis and synergized with tested chemothera-peutic drugs to induce efficient apoptosis in human colorectal cancer cells. Sequential, inverted sequential and simultaneous treatment of cancer cells with combi-nations of chemotherapeutic drugs and Rosco arrested the growth of human colorectal cancer cells at various phases of the cell cycle as follows: Taxol/Rosco (G2/M-and S-phases), 5-FU/Rosco (S-phase), Dox/Rosco (S-phase) and Vinb/Rosco (G2/M-and S-phases). CONCLUSION: Since the eff icacy of many anticancer drugs depends on their ability to induce apoptotic cell death, modulation of this parameter by cell cycle inhibi-tors may provide a novel chemo-preventive and chemo-therapeutic strategy for human colorectal cancer.

关键词： Human colorectal cancer cell lines Cyclindependent kinase inhibition Chemosensitization Synergy Apoptosis Cell cycle

Dolomite apatite separation by amphoteric collector in presence of bacteria

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Journal of Central South University 2013年第6期20卷 1645-1652页

作者： Elmahdy Ahmed El-Mofty salah Abdel-Khalek mohamed Abdel-Khalek Nagui El-MidanyAyman Central Metallurgical Research and Development Institute Mining Petroleum and Metallurgical Engineering DepartmentCairo University

Bioflotation represents one of the growing trends to enhance the selectivity of conventional flotation processes. It utilizes the micro-organisms to replace or to interact with the chemical reagents to increase the gap between surface properties of similar minerals and to enhance the separation selectivity. In this work, dolomite-phosphate separation was investigated using amphoteric collector （dodecyl-N-carboxyethyl-N-hyroxyethyl-imidazoline） in presence of bacteria. Two types of bacteria, Corynebacterium- diphtheriae-intermedius （CDI）, and Pseudomonas aeruginosa （PA）, were used. The collector-bacteria interaction was characterized by Fourier transform infra-red （FTIR）, frothing height and Zeta potential. The results show that the collector-bacteria interaction improves the flotation selectivity. Although, the PA positively affects the separation results, the CDI cannot lower the MgO to less than 1%. A phosphate content of 0.7% MgO and 31.77% P205 with a recovery of 68% at pH 11, 3.0 kg/t amphoteric collector, 4× 10^7 cells of PA is obtained.

关键词： dolomite phosphate amphoteric collector bacteria bio-flotation carbonate minerals

Assessment of the impact of a 10-MW grid-tied solar system on the Libyan grid in terms of the power-protection system stability

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Clean Energy 2023年第2期7卷 389-407页

作者： Feras Alasali Abdelaziz salah Saidi Naser El-Naily Othman Alsmadi mohamed Khaleel Ibrahim Ghirani Department of Electrical Engineering Faculty of EngineeringThe Hashemite UniversityPO Box 330127Zarqa 13133Jordan Department of Electrical Engineering King Khalid UniversityAbha PO Box 394Abha City 61411Saudi Arabia Universitéde Tunis El Manar Ecole Nationale d’Ingénieurs de TunisLaboratoire des SystèmesÉlectriquesTunisie Electrical Engineering Department College of Electrical and Electronics Technology-BenghaziBenghaziLibya Electrical Engineering Department Faculty of EngineeringThe University of JordanAmmanJordan Aeronautical Engineering Department College of Civil Aviation MisrataLibya

The energy market in Libya is expected to face substantial changes in the next few years:electrical energy consumption will increase by 50% within the next 4 ***,there is a plan to gradually increase renewable energy sources in the power network by 2030 to 30%.Solar photovoltaic(PV)plants will play a significant role in the energy transition and the mix of energy sources in *** article is a study conducted to investigate the challenges of power-flow management and power protection from integrating PV power plants into the Libyan power *** particular,a simulation model is built for the Kufra PV power plant(10 MW)with eight buses to assess the power network performance in terms of power quality such as voltage profile,power losses and ***,the impact of the PV plant on the short-circuit level and the power-protection system is presented under different operating *** fault ride-through(FRT)is operated using standard ambient temperature and a wide range of irradiation intensity,and is verified by using the Libyan grid *** results show that the integration of the PV plant into the grid has a significant impact on the short-circuit level and the FRT over the different fault levels and locations on the *** initial period of the three-phase fault shows that the PV plant will be disconnected from the grid due to a decrease in the root mean square value voltages where the reactive and active power of the grid reach 938 MVAR and 261 MW,*** results show that increasing the fault level will lead to an increase in injecting the active *** work is considered the first extensive investigation into the challenges of modern power-flow management and power protection for the power network system in Libya.

关键词： photovoltaic renewable energy sources power protection voltage profile fault ride-through

Essential oils from Elaeoselinum asclepium: Chemical composition, antimicrobial and antioxidant properties

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Asian Pacific Journal of Tropical Biomedicine 2016年第10期6卷 851-857页

作者： Moufida Bouchekrit Hocine Laouer mohamed Hajji Moncef Nasri Serkos Artin Haroutounian salah Akkal Laboratory of Natural Biological Resources Valorization Faculty of Sciences University of Setif Laboratory of Enzyme Engineering and Microbiology National School of Engineers of Sfax Chemistry Laboratory Agricultural University of Athens Valorization of Natural Resources Bioactive Molecules and Biological Analysis Unit Department of Chemistry University of Mentouri Constantine1

Objective: To evaluate the chemical composition of the essential oil isolated from Elaeoselinum asclepium(L.) Bertol.(E. asclepium), and test the efficiency of the essential oil as an antimicrobial and antioxidant ***: Essential oil was obtained from the aerial parts of E. asclepium by hydro distillation and analyzed by gas chromatography and gas chromatography coupled with mass spectrometry. We study for the first time the chemical composition of the essential oil of E. asclepium, followed by the in vitro antimicrobial activities, which were evaluated by agar diffusion method against six Gram-positive bacteria, five Gram-negative bacteria, and two fungi. In addition, The antioxidant activities were also investigated using assays of 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and ferricreducing ***: The analyzed essential oil of the aerial parts of E. asclepium was rich in apinene(43.9%), other compounds detected in appreciable amounts were sabinene(27.9%) and b-pinene(16.0%). The essential oil yields 1.2%, the IC50 values of essential oil in 1,1-diphenyl-2-picrylhydrazyl assay in the reducing power assay were 48.26 mg/m L and at 1 mg/m L, respectively. The absorbance value of essential oil at 700 nm was0.956. The antimicrobial effect was higher on Candida albicans ATCC 1024 strain with the inhibition zone 14.5 mm than bacteria and ***: The essential oil of E. asclepium has antimicrobial and antioxidant activities. These species may be used as an important source of natural antimicrobial and antioxidant agents.

关键词： Elaeoselinum asclepium Apiaceae Essential oil Antimicrobial activity Antioxidant activity Reducing power

Circulating microRNA 9-3p and serum endocan as potential biomarkers for hepatitis C virus-related hepatocellular carcinoma

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World Journal of Hepatology 2021年第11期13卷 1753-1765页

作者： Amany mohamed salah Eldin Wahb mohamed El Kassas Ahmed Kamal Khamis Mostafa Elhelbawy Nesreen Elhelbawy Mona salah Eldin Habieb Department of Medical Biochemistry and Molecular Biology Faculty of MedicineHelwan UniversityCairo 11795Egypt Department of Endemic Medicine Faculty of MedicineHelwan UniversityCairo 11795Egypt Department of Hepatology and Gastroenterology National Liver InstituteMenoufia UniversityShebin Elkom 32512MenoufiaEgypt Department of Medical Biochemistry and Molecular Biology Faculty of MedicineMenoufia UniversityShebin Elkoum 3511Egypt

BACKGROUND The high mortality rate of hepatocellular carcinoma(HCC)in Egypt is due mainly to the increasing prevalence of hepatitis C virus infection(HCV)and late diagnosis of the ***(miRNA),which regulate tumor proliferation and metastasis in HCC,may serve as a useful diagnostic approach for the early detection of HCC,thus decreasing its ***,endocan is a protein with angiogenic and inflammatory properties that are associated with tumor progression and poor *** To analyze the levels of miRNA 9-3p and endocan in HCV-infected HCC patients and correlate them with clinicopathological *** We compared levels of endocan and circulating miRNA 9-3p from 35 HCVrelated HCC patients to 33 patients with HCV-induced chronic liver disease and 32 age and gender matched healthy controls recruited from inpatient and outpatient clinics of the National Liver Institute,Menoufia University,Egypt in the period from January to March 2021 in a case-control *** samples from all groups were analyzed for *** was measured by enzymelinked immunosorbent assays,and the expression levels of circulating miRNA 9-3p were measured by real-time quantitative reverse transcriptase *** The levels of circulating miRNA 9-3p were significantly lower in the HCC group compared to the chronic liver disease(P<0.001)and control(P<0.001)groups,while levels in the chronic liver disease were significantly lower than those in the control group(P<0.001).The levels of serum endocan were significantly higher in the HCC group compared to the chronic liver disease(P<0.001)and control(P<0.001)*** miRNA 9-3p and endocan performed better thanα-fetoprotein in discriminating HCC patients from cirrhosis and healthy *** levels of miRNA 9-3p were significantly inversely correlated to vascular invasion(P=0.002),stage of advancement of Barcelona Clinical Liver Cancer(P<0.001)and the metastatic site(P<0.001)of the HCC ***

关键词： MicroRNA 9-3p Hepatocellular carcinoma Endocan Diagnostic Biomarker Egypt

Medical treatment for sphincter of oddi dysfunction:Can it replace endoscopic sphincterotomy?

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World Journal of Gastroenterology 2012年第14期18卷 1610-1615页

作者： Véronique Vitton salah Ezzedine Jean-Michel Gonzalez mohamed Gasmi Jean-Charles Grimaud Marc Barthet Department of Gastroenterology Hôpital NordChemin des Bourrely13915 Marseille cedex 20France

AIM:To report the results of a medical management of sphincter of oddi dysfunction(SOD) after an intermediate follow-up ***:A total of 59 patients with SOD(2 men and 57 women,mean age 51 years old) were included in this prospective *** medical treatment for one year,the patients were clinically re-evaluated after an average period of 30 ***:The distribution of the patients according to the Milwaukee's classification was the following:11 patients were type 1,34 were type 2 and 14 were type *** patients underwent an endoscopic sphincterotomy(ES) after one year of medical *** median intermediate follow-up period was 29.8 ± 3 mo(3-72 mo).The initial effectiveness of the medical treatment was complete,partial and poor among 50.8%,13.5% and 35%,respectively,of the *** the end of the follow-up period,37 patients(62.7%) showed more than 50% *** rate of improvement in patients who required ES was not significantly different compared with the patients treated conservatively(64.2% vs 62.2%,respectively).CONCLUSION:Our study confirms that conservative medical treatment could be an alternative to endoscopic sphincterotomy because,after an intermediate follow-up period,the two treatments show the same success rates.

关键词： Sphincter of oddi dysfunction Cholecystectomy Endoscopic sphincterotomy Biliary scintigraphy

Problem of living liver donation in the absence of deceased liver transplantation program:Mansoura experience

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World Journal of Gastroenterology 2014年第37期20卷 13607-13614页

作者： mohamed Abdel Wahab Hosam Hamed Tarek salah Waleed Elsarraf mohamed Elshobary Ahmed mohamed Sultan Ahmed Shehta Omar Fathy Helmy Ezzat Amr Yassen mohamed Elmorshedi mohamed Elsaadany Usama Shiha Gatrointestinal Surgery Liver Transplantation Unit Gastrointestinal Surgical Center Mansoura University Daqahlia 35516 Egypt Anesthesia Intensive Care Department Gastrointestinal Surgical Center Mansoura Faculty of Medicine Mansoura University Daqahlia 35516 Egypt Internal Medicine Department Mansoura Faculty of Medicine Mansoura University Daqahlia 35516 Egypt Radiology Department Gastrointestinal Surgical Center Mansoura University Daqahlia 35516 Egypt

We report our experience with potential donors for living donor liver transplantation(LDLT), which is the first report from an area where there is no legalized deceased donation program. This is a single center retrospective analysis of potential living donors(n = 1004) between May 2004 and December 2012. This report focuses on the analysis of causes, duration, cost, and various implications of donor exclusion(n = 792).Most of the transplant candidates(82.3%) had an experience with more than one excluded donor(median = 3). Some recipients travelled abroad for a deceased donor transplant(n = 12) and some died before finding a suitable donor(n = 14). The evaluation of an excluded donor is a time-consuming process(median = 3 d, range 1 d to 47 d). It is also a costly process with a median cost of approximately 70 USD(range 35 USD to 885 USD). From these results, living donor exclusion has negative implications on the patients and transplant program with ethical dilemmas and an economic impact. Many strategies are adopted by other centers to expand the donor pool; however, they are not all applicable in our locality. We conclude that an active legalized deceased donor transplantation program is necessary to overcome the shortage of available liver grafts in Egypt.

关键词： Living donor Liver transplantation Excluded donors Deceased donor Liver disease

On Two Natural Extensions of n-normality

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Acta Mathematica Sinica,English Series 2023年第6期39卷 1147-1152页

作者： salah MECHERI Faculty of Mathematics and informatics Mohamed El Bachir El Ibrahimi UniversityBordj Bou ArreridjAlgeria

A bounded linear operator T on a complex Hilbert space H is called n-normal if T^(*)T^(n)=T^(n)T^(*).By Fuglede’s theorem T is n-normal if and only if T^(n)is *** k,n∈*** a bounded linear operator T is said to be of typeⅠk-quasi-n-normal if T^(*k){T^(*)T^(n)-T^(n)T^(*)}T^(k)=0,and T is said to be of typeⅡk-quasi-n-normal if T^(*k){T^(*n)T^(n)-T^(n)T^(*n)}T^(k)=0.1-quasi-n-normal is called *** shall show that(1)typeⅠquasi-2-normal and typeⅡquasi-2-normal are different classes;(2)the intersection of the class of typeⅠquasi-2-normal and the class of typeⅡquasi-2-normal is equal to the class of *** also give some examples of type I k-quasi-n-normal and typeⅡ*** also show that Weyl’s theorem holds for this class of operators and every k-quasi-n-normal operator has a non trivial invariant subspace.

关键词： Normal operator n-normal operator invariant subspace