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1Interstitial cells of Cajal, the Maestro in health and disease显示文摘Interstitial cells of Cajal (ICC) are important players in the symphony of gut motility. They have a very signif icant physiological role orchestrating the normal peristaltic activity of the digestive system. They are the pacemaker cells in gastrointestinal (GI) muscles. Absence, reduction in number or altered integrity of the ICC network may have a dramatic effect on GI system motility. More understanding of ICC physiology will foster advances in physiology of gut motility which will help in a future breakthrough in the pharmacological interventions to restore normal motor function of GI tract. This mini review describes what is known about the physiologic function and role of ICCs in GI system motility and in a variety of GI system motility disorders.Randa M Mostafa Yasser M Moustafa Hosam Hamdy 2010World Journal of Gastroenterology2010,16,26:56
2C3-Modules显示文摘在如果每当 A 和 B 是 M 和 B=0 的直接被加数时,那么 B 是 M 的一个被加数,模块 M 被称为一个 C3 模块的地方, Utumi 在 self-injective 戒指上识别的连续性条件之一是 C3 条件。除了 injective 和 direct-injective 模块, C3 模块的班包括 semisimple,连续、不能分解、常规的模块。确实,每枚可交换的戒指是一枚 C3 戒指。在这份报纸,我们以 C3 条件提供模块的上述提及的班的一个一般、统一的处理,并且建立戒指的几个众所周知的班的新描述。Ismail Amin Yasser Ibrahim Mohamed Yousif 2015Algebra Colloquium2015,22,4:11
3Hepato-cardiac disorders显示文摘Understanding the mutual relationship between the liver and the heart is important for both hepatologists and cardiologists. Hepato-cardiac diseases can be classified into heart diseases affecting the liver, liver diseases affecting the heart, and conditions affecting the heart and the liver at the same time. Differential diagnoses of liver injury are extremely important in a cardiologist's clinical practice calling for collaboration between cardiologists and hepatologists due to the many other diseases that can affect the liver and mimic haemodynamic injury. Acute and chronic heart failure may lead to acute ischemic hepatitis or chronic congestive hepatopathy. Treatment in these cases should be directed to the primary heart disease. In patients with advanced liver disease, cirrhotic cardiomyopathy may develop including hemodynamic changes, diastolic and systolic dysfunctions, reduced cardiac performance and electrophysiological abnormalities. Cardiac evaluation is important for patients with liver diseases especially before and after liver transplantation. Liver transplantation may lead to the improvement of all cardiac changes and the reversal of cirrhotic cardiomyopathy. There are systemic diseases that may affect both the liver and the heart concomitantly including congenital, metabolic and inflammatory diseases as well as alcoholism. This review highlights these hepatocardiacYasser Mahrous Fouad Reem Yehia 2014World Journal of Hepatology2014,6,1:10
4Current Status and Future Challenges of Weather Radar Polarimetry: Bridging the Gap between Radar Meteorology/Hydrology/Engineering and Numerical Weather Prediction显示文摘After decades of research and development, the WSR-88 D(NEXRAD) network in the United States was upgraded with dual-polarization capability, providing polarimetric radar data(PRD) that have the potential to improve weather observations,quantification, forecasting, and warnings. The weather radar networks in China and other countries are also being upgraded with dual-polarization capability. Now, with radar polarimetry technology having matured, and PRD available both nationally and globally, it is important to understand the current status and future challenges and opportunities. The potential impact of PRD has been limited by their oftentimes subjective and empirical use. More importantly, the community has not begun to regularly derive from PRD the state parameters, such as water mixing ratios and number concentrations, used in numerical weather prediction(NWP) models.In this review, we summarize the current status of weather radar polarimetry, discuss the issues and limitations of PRD usage, and explore potential approaches to more efficiently use PRD for quantitative precipitation estimation and forecasting based on statistical retrieval with physical constraints where prior information is used and observation error is included. This approach aligns the observation-based retrievals favored by the radar meteorology community with the model-based analysis of the NWP community. We also examine the challenges and opportunities of polarimetric phased array radar research and development for future weather observation.Guifu ZHANG Vivek N.MAHALE Bryan J.PUTNAM Youcun QI Qing CAO ANDrew D.BYRD Petar BUKOVCIC Dusan S.ZRNIC Jidong GAO Ming XUE Youngsun JUNG Heather D.REEVES Pamela L.HEINSELMAN AlexANDer RYZHKOV Robert D.PALMER Pengfei ZHANG Mark WEBER Greg M.MCFARQUHAR Berrien MOORE III Yan ZHANG Jian ZHANG J.VIVEKANANDAN Yasser AL-RASHID Richard L.ICE Daniel S.BERKOWITZ Chong-chi TONG Caleb FULTON Richard J.DOVIAK 2019Advances in Atmospheric Sciences2019,36,6:9
5Single-operator, single-session EUS-guided anterograde cholangiopancreatography in failed ERCP or inaccessible papilla显示文摘Janak N. Shah Fernando Marson Frank Weilert Yasser M. Bhat Thai Nguyen-Tang Richard E. Shaw Kenneth F. Binmoeller 2012Gastrointestinal Endoscopy2012,,1:5
6Toward an operating speed profile model for rural two-lane roads in Egypt显示文摘The geometric design, especially the horizontal and vertical alignments, of rural two-lane highway facilities is considered one of the most important factors affecting the quality of traffic service and safety. A consistent highway geometric design is defined to be one that conforms to the driver's expectations. In order to calculate the main measures of design consistency, an accurate operating speed profile model for road alignment is needed.Studies have shown that operating speed models are country dependent due to varying demographics, driver attitudes, habits, etc. This paper develops a speed profile model for two-lane rural roads in Egypt. This includes the development of operating speed models for horizontal curves and tangents, as well as the study of the characteristics and relationships between acceleration and deceleration rates before and after horizontal curves. The study uses a desert rural two-lane, two-way road sections that connect the city of Sohag with the city of Hurghada, in Upper Egypt. All geometric characteristics were obtained from highway authority. Speed data regarding individual drivers traveling on selected two-lane rural road sections were sampled using an on-board GPS system. The study confirms the finding in previous research that curvature is the most important factor in determining the speed on horizontal curves. Moreover, tangent length is the most important factor in determining operating speeds at tangents. The acceleration and deceleration characteristics were derived to gain an understanding of the behavior of individual vehicles traveling through curves of varying radii and lengths as well as preceding tangent length. Several operating speed models were developed for tangents and curves as well as for acceleration and deceleration rates. Incredibly effective, these models can be used for design consistency evaluations.Ibrahim H.Hashim Talaat A.Abdel-Wahed Yasser Moustafa 2016Journal of Traffic and Transportation Engineering(English Edition)2016,3,1:5
7A simplified approach to directly consider intact rock anisotropy in Hoek——Brown failure criterion显示文摘Many rock types have naturally occurring inherent anisotropic planes,such as bedding planes,foliation,or flow structures.Such characteristic induces directional features and anisotropy in rocks' strength and deformational properties.The HoekeBrown(HeB) failure criterion is an empirical strength criterion widely applied to rock mechanics and engineering.A direct modification to HeB failure criterion to account for rock anisotropy is considered as the base of the research.Such modification introduced a new definition of the anisotropy as direct parameter named the anisotropic parameter(Kb).However,the computation of this parameter takes much experimental work and cannot be calculated in a simple way.The aim of this paper is to study the trend of the relation between the degree of anisotropy(Rc) and the minimum value of anisotropic parameter(Kmin),and to predict the Kmindirectly from the uniaxial compression tests instead of triaxial tests,and also to decrease the amount of experimental work.Mohamed A.Ismael Hassan F.Imam Yasser El-Shayeb 2014Journal of Rock Mechanics and Geotechnical Engineering2014,6,5:5
8复合材料π接头渐进失效分析显示文摘针对复合材料π接头复杂的失效形式,采用材料刚度退化的方法模拟结构的渐进失效过程.用Abaqus建立某复合材料π接头的三维有限元模型;采用三维Hashin失效准则和Ye分层准则判别复合材料层合板的5种失效形式,将理想弹塑性材料模型应用于胶层材料来模拟胶层材料的失效,在Abaqus中建立考虑复合材料层合板和胶层失效的分析子程序;在子程序中,定义6个场变量代表纤维拉伸破坏、纤维屈曲、基体拉伸开裂、基体压缩开裂、分层失效和胶层失效等6种失效形式.在递增的拉伸载荷作用下对所建模型进行失效分析,结果表明该方法能有效地对复合材料π接头进行初始失效位置及载荷的判别和最终失效预测.陈珅艳 林志伟 MOHAMED Yasser Mahmoud 黄海 梁宪珠 2011计算机辅助工程2011,20,3:4
9Percutaneous devices for left atrial appendage occlusion: A contemporary review显示文摘Patient with atrial fibrillation(AF) are at risk of developing stroke with the left atrial appendage(LAA) being the most common site for thrombus formation. If left untreated, AF is associated with 4 to 5 folds increase in the risk of ischemic stroke in all age groups. About 5% to 15% of AF patients have atrial thrombi on transesophageal echocardiography, and 91% of those thrombi are located in the LAA in patient with nonrheumatic AF. Although oral anticoagulants are the gold-standard treatment for stroke prevention in patients with non-valvular AF,some patients are at high risk of bleeding and deemed not candidates for anticoagulation. Therefore, LAA occlusion(LAAO) has emerged as alternative approach for stroke prevention in those patients. Surgical LAAO is associated with high rate of unsuccessful closure and recommended only in patients with AF and undergoing cardiac surgery. Percutaneous LAAO uses transvenous access with trans-septal puncture and was first tested using the PLAATO device.Watchman is the most common and only Food and Drug Administration(FDA)approved device for LAAO. LAAO using Watchman device is non-inferior to warfarin therapy in preventing ischemic stroke/systemic thromboembolism.However, it is associated with lower rates of hemorrhagic stroke, bleeding and death. Amplatzer is another successful LAAO device that has CE mark and is waiting for FDA approval. Optimal antithrombotic therapy post LAAO is still under debate and highly patient-specific. The aim of this paper is to systematically review the current literature to evaluate the efficacy and safety of different LAAO devices.Homam Moussa Pacha Yasser Al-khadra Mohamad Soud Fahed Darmoch Abdulghani Moussa Pacha M Chadi Alraies 2019World Journal of Cardiology2019,11,2:4
10Barrett's esophagus:Prevalence and risk factors in patients with chronic GERD in Upper Egypt显示文摘AIM:To determine the prevalence and possible risk factors of Barrett's esophagus(BE) in patients with chronic gastroesophageal reflux disease(GERD) in El Minya and Assuit, Upper Egypt.METHODS:One thousand consecutive patients with chronic GERD symptoms were included in the study over 2 years.They were subjected to history taking including a questionnaire for GERD symptoms, clinical examination and upper digestive tract endoscopy.Endoscopic signs suggestive of columnar-lined esophagus(CLE) were defined as mucosal tongues or an upward shift of the squamocolumnar junction.BE was diagnosed by pathological examination when specialized intestinal metaplasia was detected histologically in suspected CLE.pH was monitored in 40 patients.RESULTS:BE was present in 7.3% of patients with chronic GERD symptoms, with a mean age of 48.3 ± 8.2 years, which was signif icantly higher than patients with GERD without BE(37.4 ± 13.6 years).Adenocarcinomawas detected in eight cases(0.8%), six of them in BE patients.There was no signiflcant difference between patients with BE and GERD regarding sex, smoking, alcohol consumption or symptoms of GERD.Patients with BE had significantly longer esophageal acid exposure time in the supine position, measured by pH monitoring.CONCLUSION:The prevalence of BE in patients with GERD who were referred for endoscopy was 7.3%.BE seems to be associated with older age and more in patients with nocturnal gastroesophageal reflux.Yasser M Fouad Madiha M Makhlouf Heba M Tawfik Hussein El Amin Wael Abdel Ghany Hisham R El-khayat 2009World Journal of Gastroenterology2009,15,28:4
11基于加铺层疲劳试验仪的沥青混合料开裂及自愈性能研究新方法显示文摘沥青路面在承受重复荷载和间歇期时会产生疲劳及自愈过程。目前主要利用加铺层疲劳试验仪对裂缝穿透试件时的荷载重复次数进行计数来评价这些现象,但此过程耗时较长,且结果具有较大变异性。该文提出了一种基于粘弹性断裂力学及有限元模型来预测沥青混合料中裂缝实际增长率、开裂及自愈性能的分析方法,该方法使用加铺层疲劳试验仪对室内及现场试件进行测试。另外,利用实际试件的测试结果对该方法进行了验证。结果表明:这种测试方法比之前只利用加铺层疲劳试验仪的方法更快、更便宜,而且结果更具有可复现性,室内试件非破坏性能的变化系数与测试结果具有可比性。李艳博 李波 杨小龙 Yasser Koohi Rong Luo Robert L. Lytton Tom Scullion 2015中外公路2015,35,3:4
12The Epidemiology of Cholangiocarcinoma显示文摘Yasser Shaib Hashem El-Serag 2004Semin Liver Dis2004,,02:3
13Sequence Stratigraphy and Rudist Facies Development of the Upper Barremian-Lower Cenomanian Platform, Northern Sinai, Egypt显示文摘The Lower Cretaceous sections in northern Sinai are composed of the Risan Aneiza(upper Barremian-middle Albian) and the Halal(middle Albian-lower Cenomanian) formations. The facies reflect subtle paleobathymetry from inner to outer ramp facies. The inner ramp facies are peritidal, protected to open marine lagoons, shoals and rudist biostrome facies. The inner ramp facies grade northward into outer ramp deposits. The upper Barremian-lower Cenomanian succession is subdivided into nine depositional sequences correlated with those recognized in the neighbouring Tethyan areas. These sequences are subdivided into 19 medium-scale sequences based on the facies evolution, the recorded hardgrounds and flooding surfaces, interpreted as the result of eustatic sea level changes and local tectonic activities of the early Syrian Arc rifting stage. Each sequence contains a lower retrogradational parasequence set that constituted the transgressive systems tracts and an upper progradational parasequence set that formed the highstand systems tracts. Nine rudist levels are recorded in the upper Barremian through lower Cenomanian succession at Gabal Raghawi. At Gabal Yelleg two rudist levels are found in the Albian. The rudist levels are associated with the highstand systems tract deposits because of the suitability of the trophic conditions in the rudist-dominated ramp.Yasser SALAMA Michael GRAMMER Shaban SABER Soheir EL-SHAZLY Gouda ABDEL-GAWAD 2018Acta Geologica Sinica(English Edition)2018,92,1:3
14Rising incidence of intrahepatic cholangiocarcinoma in the United States: a true increase?显示文摘Yasser H Shaib Jessica A Davila Kathryn McGlynn Hashem B El-Serag 2003Journal of Hepatology2003,,3:3
15Silymarin-laden PVP-PEG polymeric composite for enhanced aqueous solubility and dissolution rate: Preparation and in vitro characterization显示文摘The aim of this work was to develop, optimize and characterize a silymarin-laden polyvinylpyrrolidone(PVP)-polyethylene glycol(PEG) polymeric composite to resolve low aqueous solubility and dissolution rate problem of the drug. A number of silymarin-laden polymeric formulations were fabricated with different quantities of PVP K-30 and PEG 6000 by the solvent-evaporation method. The effect of PVP K-30 and PEG 6000 on the aqueous solubility and dissolution rate was investigated. The optimized formulation and its constituents were characterized using powder X-ray diffraction(PXRD), differential scanning calorimetry(DSC), scanning electron microscopy(SEM) and Fourier transform infrared spectroscopy(FTIR) techniques. Both the PEG 6000 and PVP K-30 positively affected the aqueous solubility and dissolution rate of the drug. In particular, a formulation consisting of silymarin, PVP K-30 and PEG 6000(0.25/1.5/1.5, w/w/w) furnished the highest solubility(24.3972.95 mg/mL) and an excellent dissolution profile( $100% in 40 min). The solubility enhancement with this formulation was $ 1150-fold as compared to plain silymarin powder. Moreover, all the constituents existed in the amorphous state in this silymarin-laden PVP-PEG polymeric composite. Accordingly, this formulation might be a promising tool to administer silymarin with an enhanced effect via the oral route.Abid Mehmood Yousaf Usman Rashid Malik Yasser Shahzad Tariq Mahmood Talib Hussain 2019Journal of Pharmaceutical Analysis2019,9,1:3
16Suck-ligate-unroof-biopsy by using a detachable 20-mm loop for the diagnosis and therapy of small subepithelial tumors (with video)显示文摘Kenneth F. Binmoeller Janak N. Shah Yasser M. Bhat Steve D. Kane 2013Gastrointestinal Endoscopy2013,,:3
17ROBUSTNESS OF EQUILIBRIA IN THE GRAPH MODEL FOR CONFLICT RESOLUTION显示文摘A novel approach for assessing the robustness of an equilibrium in conflict resolution is presented.Roughly,an equilibrium is robust if it is resilient,or resistant to deviation.Robustness assessment is based on a new concept called Level of Freedom,which evaluates the relative freedom of a decision maker to escape an equilibrium.Resolutions of a conflict can be affected by changes in decision makers' preferences,which may destabilize an equilibrium,causing the conflict to evolve.Hence,a conflict may become long-term and thereby continue to evolve,even after reaching an equilibrium.The new robustness measure is used to rank equilibria based on robustness,to facilitate distinguishing equilibria that are relatively sustainable.An absolutely robust equilibrium is a special case in which the level of freedom is at an absolute minimum for each individual stability definition.Yasser T.Matbouli D.Marc Kilgour Keith W.Hipel 2015Journal of Systems Science and Systems Engineering2015,24,4:3
18Gut microbiota in various childhood disorders:Implication and indications显示文摘Gut microbiota has a significant role in gut development,maturation,and immune system differentiation.It exerts considerable effects on the child's physical and mental development.The gut microbiota composition and structure depend on many host and microbial factors.The host factors include age,genetic pool,general health,dietary factors,medication use,the intestine's pH,peristalsis,and transit time,mucus secretions,mucous immunoglobulin,and tissue oxidation-reduction potentials.The microbial factors include nutrient availability,bacterial cooperation or antagonism,and bacterial adhesion.Each part of the gut has its microbiota due to its specific characteristics.The gut microbiota interacts with different body parts,affecting the pathogenesis of many local and systemic diseases.Dysbiosis is a common finding in many childhood disorders such as autism,failure to thrive,nutritional disorders,coeliac disease,Necrotizing Enterocolitis,helicobacter pylori infection,functional gastrointestinal disorders of childhood,inflammatory bowel diseases,and many other gastrointestinal disorders.Dysbiosis is also observed in allergic conditions like atopic dermatitis,allergic rhinitis,and asthma.Dysbiosis can also impact the development and the progression of immune disorders and cardiac disorders,including heart failure.Probiotic supplements could provide some help in managing these disorders.However,we are still in need of more studies.In this narrative review,we will shed some light on the role of microbiota in the development and management of common childhood disorders.Nermin Kamal Saeed Mohammed Al-Beltagi Adel Salah Bediwy Yasser El-Sawaf Osama Toema 2022World Journal of Gastroenterology2022,28,18:3
19Evaluation of the remaining lateral torsional buckling capacity in corroded steel members显示文摘Corrosion is one of the main causes of deterioration in steel structures. Loss of thickness in flanges and web of corroded steel beams leads to reduction in section properties which can reduce the lateral torsional buckling capacity of the member. In this paper, thickness loss data were compiled from four samples of corrosion damaged I-beams removed from a petro-chemical plant. Visual examination of the four corroded beams showed that they were corroded uniformly. To improve the accuracy of the results, a large number of measurements for surface roughness were taken for each beam, totally 770 values to obtain the average thickness of flanges and web of each beam. The data was used to develop a corrosion decay model in order to calculate the percentage remaining lateral torsional buckling capacity of long and short span beams which are laterally unrestrained. To estimate the percentage of remaining lateral torsional buckling capacity in the corroded damaged I-beams, the readily available minimum curves for different types of universal beams in conjunction with information on the thickness loss were used. The results can be used by practicing engineers for better estimation on the service life of deteriorated steel structures.Yasser SHARIFI Reza RAHGOZAR 2010Journal of Zhejiang University-Science A(Applied Physics & Engineering)2010,11,11:3
20Functional roles of ornithine decarboxylase and arginine decarboxylase during the peri-implantation period of pregnancy in sheep显示文摘Background: Polyamines stimulate DNA transcription and m RNA translation for protein synthesis in trophectoderm cells, as well as proliferation and migration of cells; therefore, they are essential for development and survival of conceptuses(embryo/fetus and placenta). The ovine conceptus produces polyamines via classical and non-classical pathways. In the classical pathway, arginine(Arg) is transformed into ornithine, which is then decarboxylated by ornithine decarboxylase(ODC1) to produce putrescine which is the substrate for the production of spermidine and spermine. In the non-classical pathway, Arg is converted to agmatine(Agm) by arginine decarboxylase(ADC), and Agm is converted to putrescine by agmatinase(AGMAT).Methods: Morpholino antisense oligonucleotides(MAOs) were designed and synthesized to inhibit translational initiation of the m RNAs for ODC1 and ADC, in ovine conceptuses.Results: The morphologies of MAO control, MAO-ODC1, and MAO-ADC conceptuses were normal. Double knockdown of ODC1 and ADC(MAO-ODC1:ADC) resulted in two phenotypes of conceptuses; 33% of conceptuses appeared to be morphological y and functional y normal(phenotype a) and 67% of the conceptuses presented an abnormal morphology and functionality(phenotype b). Furthermore, MAO-ODC1:ADC(a) conceptuses had greater tissue concentrations of Agm,putrescine, and spermidine than MAO control conceptuses, while MAO-ODC1:ADC(b) conceptuses only had greater tissue concentrations of Agm. Uterine flushes from ewes with MAO-ODC1:ADC(a) had greater amounts of arginine, aspartate, tyrosine, citrulline, lysine, phenylalanine, isoleucine, leucine, and glutamine, while uterine flushes of ewes with MAO-ODC1:ADC(b) conceptuses had lower amount of putrescine, spermidine, spermine, alanine, aspartate,glutamine, tyrosine, phenylalanine, isoleucine, leucine, and lysine.Conclusions: The double-knockdown of translation of ODC1 and ADC m RNAs was most detrimental to conceptus development and their production of interferon tau(IFNT). Agm, polyamines, amino acids, and adequate secretion of IFNT are critical for establishment and maintenance of pregnancy during the peri-implantation period of gestation in sheep.Yasser Y.Lenis Gregory A.Johnson Xiaoqiu Wang Wendy W.Tang Kathrin A.Dunlap M.Carey Satterfield Guoyao Wu Thomas R.Hansen Fuller W.Bazer 2018Journal of Animal Science and Biotechnology2018,9,2:3
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