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      • KCI등재

        Relationship between Helicobacter pylori Virulence Genes and Clinical Outcomes in Saudi Patients

        Mohammed Ali M. Marie 대한의학회 2012 Journal of Korean medical science Vol.27 No.2

        Helicobacter pylori has been strongly associated with gastritis, gastric and duodenal ulcers,and it is a risk factor for gastric cancer. Two major virulence factors of H. pylori have been described: the cytotoxin-associated gene product (cagA) and the vacuolating toxin (vacA). Since considerable geographic diversity in the prevalence of H. pylori virulence factors has been reported, the aim of this work was to determine if there is a significant correlation between different H. pylori virulence genes (cagA and vacA) in 68 patients, from Saudi Arabia, and gastric clinical outcomes. H. pylor was recognized in cultures of gastric biopsies. vacA and cagA genes were detected by polymerase chain reaction (PCR). The cagA gene was obtained with 42 isolates (61.8%). The vacA s- and m- region genotypes were determined in all strains studied. Three genotypes were found: s1/m1 (28%), s1/m2(40%) and s2/m2 (26%). The s2/m1 genotype was not found in this study. The relation of the presence of cagA and the development of cases to gastritis and ulcer was statistically significant (P < 0.05). The study showed a significant correlation between the vacA s1/m2genotype and gastritis cases, and a significant correlation between vacA s1/m1 genotype and peptic ulcer cases. The results of this study might be used for the identification of high-risk patients who are infected by vacA s1/m1 genotype of H. pylori strains. In conclusion, H. pylori strains of vacA type s1 and the combination of s1/m1 were associated with peptic ulceration and the presence of cagA gene.

      • KCI등재

        Sensitive and selective m-tolyl hydrazine chemical sensor development based on CdO nanomaterial decorated multi-walled carbon nanotubes

        Mohammed M. Rahman,M.M. Alam,Khalid A. Alamry 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.77 No.-

        In this approach, the wet-chemical (co-precipitation) technique was used to prepare the cadmium oxide(CdO) nanoparticles (NPs) decorated with multi-walled carbon nanotubes (CNT) at low temperature. Thepowder XDR, UV–vis, TEM, XPS, and FTIR spectroscopy were used for detail characterization of thesynthesized CdO/CNT nanocomposite (NCs). A thin layer of CdO/CNT NCs was deposited onto a glassycarbon electrode (GCE) with conducting coating binder to obtain a chemical sensor which wassubsequently used to detect m-tolyl hydrazine hydrochloride (m-THyd) in buffer medium byelectrochemical approach for environmental safety. The proposed m-THyd chemical sensor exhibitedlong-term stability, good selectivity, broad linear dynamic range, lower detection limit, and enhancedelectrochemical response. The calibration curve of the current vs concentration of m-THyd was found tobe linear (r2 = 0.9903) over the linear dynamic range (LDR) of 0.01 nM to 0.1 mM. The sensitivity(25.7911 mA mM cm 2) of chemical sensor was calculated from the slope of calibration curve and surfacearea of GCE (0.0316 cm2) and the detection limit (4.0 0.2 pM) was estimated from the signal to noiseratio at 3. These preliminary results suggest that the newly developed CdO/CNT NCs nanocompositecould be promising electrochemical sensors for the detection of hazardous toxins to clean theenvironment in broad scales.

      • KCI등재

        Impacts of Sr2+ and Annealing Temperature on the Composition, Structure, and Magnetic Properties of SrFe12O19 Synthesized by Tartrate Precursor Route

        M. M. Hessien,Mahdi Albogamy,Mohammed Alsawat,Abdulrahman Alhadhrami 한국자기학회 2023 Journal of Magnetics Vol.28 No.2

        Hexagonal M-type strontium ferrite (SrFe12O19) has been fabricated through a simple self-combustion tartrate precursor approach to producing a homogenous powder with a homogeneous shape and limited size distribution at low-processing temperatures. The impacts of the Sr2+:Fe3+ molar ratio and the annealing temperature on formation, morphological structure, crystallite size, and magnetic performance were studied. The powders were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) profile, and vibrating sample magnetometer (VSM). The development of crystalline single-phase Sr-hexagonal ferrite occurred at ≥ 1100 °C and Sr2+:Fe3+ molar ratios 1.1:12-1.3:12. Existence of α-Fe2O3 and impurities in the hexagonal powders increases the lattice parameters while higher annealing temperature decreases it. The c/a ratios of as-prepared samples (~3.911-3.920) are comfortably within the range of ratios for M-type structures. The platelet-like structure has appeared at an annealing temperature ≥ 1000 °C. The wide saturation magnetization (37.26-66.19 emu/g) and coercivity (275.09-2107.8Oe) were accomplished at diverse synthesis conditions and reached the greatest values at 1350 °C. The squareness ratios (Mr/Ms) for all studied samples are <0.5, which is for multimagnetic domains.

      • SCOPUSKCI등재

        Association of Mycoplasma pneumoniae in Asthma Pathogenesis

        Marie, Mohammed Ali M. The Korean Academy of Tuberculosis and Respiratory 2008 Tuberculosis and Respiratory Diseases Vol.65 No.4

        The role of atypical bacterial infection in the pathogenesis of asthma is a subject of continuing debate. There is an increasing body of literature concerning the association between the atypical bacteria such as Mycoplasma pneumoniae (M. pneumoniae) and asthma pathogenesis. Moreover, many studies investigating such a link have been uncontrolled and have provided conflicting evidence, in part due to the difficulty in accurately diagnosing infection with these atypical pathogens. This manuscript will review the relationship between M. pneumoniae infection and asthma pathogenesis.

      • KCI등재

        Inducing Potential Mutants in Bread Wheat Using Different Doses of Certain Physical and Chemical Mutagens

        Ghada M.Sh.M. Abaza,Hassan A. Awaad,Zakaria M. Attia,Khalid S. Abdel-lateif,Mohamed A. Gomaa,Safy M.Sh.M. Abaza,Elsayed Mansour 한국육종학회 2020 Plant Breeding and Biotechnology Vol.8 No.3

        Mutation is an effective strategy not only for creating novel variation into crop genome but also for direct releasing adapted and high-yielding genotypes. The current work explores inducing genetic variability in bread wheat using physical and chemical mutagens. Three wheat cultivars were treated by three mutagens; gamma irradiation (five doses; 250, 300, 350, 400 and 450 Gray); laser ray (three treatments; 1, 1.5, and 2 hour exposure) and EMS (three concentrations; 0.2, 0.3 and 0.4%). Besides, a combination of physical (laser) and chemical (EMS) mutagens using middle range of each treatment (1.5 hour laser and 0.3% EMS) was attempted to be applied. The treated seeds were sown in the first season and 4050 M1 plants were harvested. The harvested seeds were sown in the second season, and 78750 M2 plants were obtained. The selection was performed in second season (M2) based on morpho-physiological and yield traits; flag leaf area, flag leaf chlorophyll content, plant height, spike length, grain yield per plant and its components. Based on evaluated traits fourteen mutants were selected to be evaluated in the third generation (M3). The results indicated that the used mutagens had direct impact and significantly improved agronomic traits in derivative mutants compared to their parent cultivars. Moreover, the maximum increment in yield related traits were obtained by 0.4% EMS, 1 and 2 hour-laser, 350-Gy, 1.5 hour × 0.3% EMS and 250-Gy. The obtained results highlighted the importance of these doses of applied mutagens to induce useful genetic variability in bread wheat for improving grain yield and contributing traits.

      • KCI등재

        First Measurements of Carbonaceous Aerosol across Urban, Rural and Residential Areas in Jeddah City, Saudi Arabia

        Iqbal M. Ismail,Ahmad S. Summan,Jalal M. Basahi,Essam Hammam,Mohamed F. Yassin,Ibrahim A. Hassan 한국대기환경학회 2021 Asian Journal of Atmospheric Environment (AJAE) Vol.15 No.2

        Concentrations of black carbon (BC), organic carbon (OC), and total suspended particulate matter (TSP) were simultaneously assessed in urban, rural and residential areas in Jeddah city for one year from January to December 2017. It was aimed in the present study to provide information about the spatial and seasonal variability of these aerosol species in Jeddah, and insight into sources, processes and effects of meteorological conditions. To the best of our knowledge, this is the first study investigating the variability of carbonaceous aerosols (OC and BC) in Saudi Arabia. The average concentrations of OC, BC, and TSP varied spatially and temporally. The annual average concentrations of OC, BC, and TSP were 134.05, 7.16, and 569.41 μg m-3 and 34.32, 5.14, and 240.64 μg m-3 and 10.67, 4.39 and 101.31 μg m-3 in the urban, residential and rural areas, respectively. Moreover, there was a clear seasonal variation in the concentration of carbonaceous aerosols; the highest concentrations were recorded in February and September, while the lowest concentrations of OC were recorded during April, May and August in the urban, residential and rural sites, respectively. Nevertheless, the lowest concentrations of BC were recorded during March in the urban and residential sites and during November in the rural site. The relative concentrations of OC and BC to the TSP were relatively high, and they have a significant correlation with prevalent wind speed (-0.636, and -0.581 in the urban area), (-0.539 and -0.511 in the residential area), and (-0.508 and -0.501 in the rural area), respectively. The marked differences in the concentrations of BC and OC were reflected on OC/BC ratio, which is a good representative of different source types. This preliminary study showed that the potential local sources were emissions from traffic (fossil fuel), biomass burning, anthropogenic activities (e.g. car drifting and outdoor cooking), and industrial activities. The present study suggest the presence of highly inefficient combustion sources and highlight the need for the regulation of such emissions.

      • SCOPUSKCI등재

        Incidence and Antimicrobial Susceptibility of Mycoplasma pneumoniae in Saudi Arabia

        Marie, Mohammed Ali M. The Korean Society for Microbiology 2010 Journal of Bacteriology and Virology Vol.40 No.4

        Mycoplasma pneumoniae is increasingly recognized as a common and an important pathogen in community-acquired respiratory tract infections (RTIs) and pneumonia, particularly in school-age children and young adults. To determine the incidence and antibiotic susceptibility of M. pneumoniae at the main hospitals in Riyadh, Saudi Arabia, we studied 552 respiratory samples from patients diagnosed with different clinical diagnosis. The isolation, identification, enumeration and antibiotic resistance test for M. pneumoniae were performed using Pneumofast kit. There were 194 patients (35.1%) with current M. pneumoniae infection, mostly among younger age groups, with pneumonia the most common underlying clinical condition. All tested isolates were susceptible to four antibiotics included in the Pneumofast kit, doxycycline, minocycline, ciprofloxacine and erythromycin. The findings suggest that M. pneumonia infection in Saudi Arabia is more common among younger age groups, and pneumonia is the most common underlying clinical condition among patients with M. pneumoniae infection, that cannot be distinguished from other respiratory infections on the basis of clinical and radiographic diagnosis alone.

      • KCI등재

        Optimization of Water Pipe Network and Formulation of Pumping Rate

        Medhat M. H. El-Zahar,Mohamed M. M. Amin 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.7

        Minimizing water delivery costs and increasing water supply dependability are the two keyobjectives in designing and operating of water distribution systems. An analytical solution forthe best pipe diameters of a water distribution pipe network was created in this study. The rawwater was collected from a water canal and transported to a treatment plant (WTP). Thecleansed water was pushed into the water distribution network via the pumping station. Thederivative approach was used in the optimization process, and the cost functions incorporating thevarious capital and operating expenses were used. The initial diameters were adjusted toreach the least-cost diameters. The study shows that the optimum design of a pipe network(PNW) achieves saving a total cost of about 12.3% after utilizing our unique method. Theoptimal pumping rate in the PNW can also be determined using an analytical approach thatconsiders the optimum value that occurs when the minor and friction losses in the entirenetwork are at their lowest. The analytical solution for the optimum pumping rate shows arigid value of optimum pumping rate (Qopt) which is 5296.32 m3/day. On comparativeestimates, this figure is very close to that of 5,300 m3/day interpreted from the graphicalsolution, with negligible deviation. The total cost and optimum pumping rate results for theanalyzed PNW example demonstrate the correctness of the analytical solutions, reliability, anddependability of the assumptions.

      • Functional topography of the primary motor cortex during motor execution and motor imagery as revealed by functional MRI

        Makary, Meena M.,Eun, Seulgi,Soliman, Ramy S.,Mohamed, Abdalla Z.,Lee, Jeungchan,Park, Kyungmo Wolters Kluwer Health | Lippincott Williams Wilkin 2017 NEUROREPORT - Vol.28 No.12

        <P>Controversy exists regarding the involvement of the primary motor cortex (M1) during motor imagery (MI) and also regarding the differential somatotopic representation of motor execution (ME) and mental simulation of movement, that is, MI within M1. Although some research reported clear M1 involvement during MI without overt motor output, others did not. However, possible somatotopic representation between execution and imagery has not been clearly investigated to date. The aim of the present study was to aid in the resolution of this controversy by investigating the possible involvement of M1 during MI, and the differential, within M1, somatotopic representation between execution and imagery by quantitatively assessing different location markers such as activation peak and center of mass as well as intensity differences between the two tasks in case of with and without the overlap between the two representations. Forty-one healthy volunteers participated in two functional MRI runs of mouth-stretching ME and MI tasks. Our findings suggest the clear involvement of M1 (BA 4) during MI with lower signal intensity compared with ME, and further showed distinct centers for each representation along the y-axis (anteroposterior plane), with MI showing more involvement of the anterior sector of M1 (BA 4a), whereas ME recruited more of the posterior sector (BA 4p). These results parallel the pioneering findings of a functional distinction between BA 4a and BA 4p, where BA 4a is more involved in the cognitive aspects of MI, whereas BA 4p is more related to executive function, promoting the idea of distinctive somatotopic mapping between execution and imagery within M1 sectors.</P>

      • KCI등재

        Dental Panoramic Radiographic Indices as a Predictor of Osteoporosis in Postmenopausal Saudi Women

        Ayman Zaky Elsamanoudy,Madiha Mahmoud Gomaa,Rabab Mohammed Feteih,Najlaa Mohammed AlAmoudi,Ayman Zaky Elsamanoudy,Mohammed Ahmed Hassanien,Mohammed-Salleh M. Ardawi 대한골대사학회 2018 대한골대사학회지 Vol.25 No.3

        Background: Many oral presentations of osteoporosis-a bone metabolic disease-were recorded. Thus, we aimed to assess panoramic radiomorphometric indices with bone mineral density (BMD) values among Saudi postmenopausal women and its importance in the prediction of osteoporosis. Methods: A total of 431 Saudi women were enrolled in this study. Panoramic radiographs were obtained at the time of BMD measurement. Subjects were fatherly classified into; normal BMD, osteopenia, and osteoporosis groups. Serum follicle-stimulating hormone, luteinizing hormone (LH), estradiol (E2), 25-hydroxy-vitamin D (25[OH]D) and intact-parathyroid hormone were measured. Moreover, serum creatinine, calcium, and phosphate, together with serum osteocalcin (s-OC), procollagen type I N-terminal propeptide (s-PINP) and cross-linked C-terminal telopeptide of type 1 collagen (s-CTX) were measured. Receiver-operator curve (ROC) curve analysis for use of mandibular cortical width (MCW), panoramic mandibular index (PMI), and maxillary-mandibular ratio (M/M ratio) to differentiate women with osteoporosis or osteopenia from normal subjects was calculated. Cut off values of 4.6 at T score <-1 and 4.1 at T score ≤-2.5 were used. Results: Body mass index is significantly low in the osteoporotic group. There is no significant difference in serum levels of LH, E2, calcium, phosphate, and 25(OH)D between the studied groups. Moreover, s-OC, C-terminal propeptide of procollagen type I, s-PINP, s-CTX, and urinary-CTX are significantly higher in osteoporosis than normal and osteopenia groups. ROC curve analysis revealed that MCW and PMI showed significant data while M/M ratio is non-significant. Conclusions: It could be concluded that MCW as an important panoramic radiographic parameter can be used for prediction and diagnosis of osteoporosis in postmenopausal Saudi women with low BMD.

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