oalib

OALib Journal期刊

ISSN: 2333-9721

费用:99美元

投稿

时间不限

2017 ( 362 )

2016 ( 753 )

2015 ( 10835 )

2014 ( 13779 )

自定义范围…

匹配条件: “S Yousef Zadeghan” ,找到相关结果约324654条。
列表显示的所有文章,均可免费获取
第1页/共324654条
每页显示
Comparing ‘remifentanil-propofol’ and ‘fentanyl-propofol’ in patients undergoing craniotomy for supratentorial space-occupying lesions
Gh Khalili,P Sajedi,S Yousef Zadeghan
Tehran University Medical Journal , 2012,
Abstract: Background: Control of intracranial pressure (ICP) before, during and after neurosurgical operations is crucially important. Therefore, trying different methods and drug combinations to attain this goal is an ongoing effort in anesthesiology. In this study we compared two combinations of a narcotic agent with propofol in neurosurgical operations to control intracranial pressure.Methods: In this prospective randomized double-blind clinical trial, we enrolled 34 patients with supratentorial brain tumors who were candidates for craniotomy in Alzahra Hospital in Isfahan, Iran from April 2008 to April 2009. The patients were randomly divided into two groups of 17, in whom the first and the second group, respectively, received a combination of "propofol and fentanyl" and a combination of "propofol and remifentanyl" as maintenance of anesthesia. The hemodynamic status, ICP during the surgery, and post-surgical complications in recovery unit were observed for and registered in a questionnaire.Results: Hemodynamic status was similar in both groups and they did not differ in recovery complications except for pain which was more prevalent in remifentanil group (P<0.03). Although the patients in fentanyl group better responded to the drug for lowering ICP than remifentanyl group, but the difference was not statistically significant.Conclusion: There is no difference between these two anesthetic agent combinations and both could be useful in the anesthesia of neurosurgical operations. However combination of propofol and fentanyl seem to be superior because of more pain relief and a smoother recovery period.
Wideband Modeling of Land-Mobile-Satellite Channel in Built-Up Environment  [PDF]
Anwar Jarndal, Mohammed S. Al Salameh, Anwar Alsaqaf, Yousef Hulba
Journal of Electromagnetic Analysis and Applications (JEMAA) , 2012, DOI: 10.4236/jemaa.2012.43013
Abstract: This paper presents a propagation model for land-mobile-satellite (LMS) wideband radio channel in built-up environment. The model characterizes the behavior of the radio channel, under shadowing and multipath effects due to buildings, with variation of the elevation angle of the satellite. The wideband parameters (coherent bandwidth and time delay spreading) for LMS channel, in residential and urban environments, are computed. These parameters can be considered as a measure of the amount of ISI (inter-symbol interference) of the radio channel, which distorts the received signal and accordingly increases the bit error rate. The calculated values for these parameters using our model, show very good agreement with the corresponding measured ones, which accordingly shows the validity of the developed model for radio channel design in satellite mobile communication systems.
Functional results after primary shoulder hemiarthroplasty for proximal humerus bone fractures
Guity MR,Yousef Sibdari S,Espandar R
Tehran University Medical Journal , 2010,
Abstract: "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 st1":*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Shoulder hemiarthroplasty is one of the established methods for management of proximal humerus fractures particularly in the types with more displacement so that fixation is not possible. Successful treatment is a challenge for shoulder surgeons especially in elderly patients. The aim of this study is to investigate the functional results and prognostic factors on shoulder hemiarthroplasty."n"nMethods: Thirty nine patients operated by one shoulder surgeon in Imam Khomeini and Shariati Hospital in Tehran, Iran, from October 2005 to February 2009 were included in this study and followed postoperatively for at least one year. Mean (±SD) age was 49.7±14.3 years. Functional results were measured by constant score and pain was scored using visual analogue score. The relationship between factors such as age, injury to surgery interval, radiographic parameters and functional results were assessed."n"nResults: Mean (±SD) constant score was 61.9±20.2. The age and injury to surgery interval showed a reverse correlation with constant score (p<0.05). There was a significant correlation between constant score and acromiohumeral interval (r=0.53) and head to tuberusity distance (-0.59). Median VAS score was 4.5 (interquartile range: 2- 5.2) that had a direct correlation with age (r=0.38) and injury to surgery interval (r=0.55) (p<0.05)."n"nConclusions: Shoulder hemiarthroplasty should be performed in minimal delay from injury and this operation should be performed by an experienced shoulder surgeon to create the best anatomic position of prostheses. Careful rehabilitation particularly in older patients is very important to improve results.
Modeling the Effect of Variable Timing of the Exhaust Valves on SI Engine Emissions for Greener Vehicles  [PDF]
Osama H. M. Ghazal, Yousef S. H. Najjar, Kutaeba J. M. Al-Khishali
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.53018
Abstract:

The problem with fixed valve timing that the valve train is set by the automaker for peak efficiency running at a specific point in the engines operating range. When the vehicle is moving slower or faster than this ideal operating point the engines combustion cycle fails to properly burn the air/fuel mixture leading to considerably compromised engine performance and wastes fuel. Variable Valve Timing (VVT) is a solution developed to overcome this engine deficiency, dynamically altering the valve's opening and closing for optimal performance at any speed. The intension in this work is to contribute towards pursuing the development of variable valve timing (VVT) for improving the engine performance. This investigation covers the effect of exhaust valve opening (EVO), and closing (EVC) angle on engine performance and emissions. The aim is to optimize engine power and brake specific fuel consumption (BSFC) where the effect of engine speed has also been considered. Power, BMEP, BSFC, NO, and CO were calculated and presented to show the effect of varying valve timing on them for all the valve timing cases. The calculations of engine performance were carried out using the simulation and analysis engineering software: LOTUS”, and engine emissions were calculated using “ZINOX” program. Sensitivity analysis shows that the reduction of 10% of (EVO) angle gave a reduction of around 2.5% in power and volumetric efficiency, also a slight increase in nitrogen oxide (NO) and carbon monoxide (CO), while a 10% decrease in (EVC) causes around 1% improvement in Power. The effects of different (VVT) from the simulations are analyzed and compared with those in the reviewed literature.

Oral Health Knowledge and Practices among Diverse University Students with Access to Free Dental Care: A Cross-Sectional Study  [PDF]
Ola B. Al-Batayneh, Arwa I. Owais, Yousef S. Khader
Open Journal of Stomatology (OJST) , 2014, DOI: 10.4236/ojst.2014.43021
Abstract: Aim: The aim of this study was to investigate oral health knowledge and practices among under-graduate university students from various disciplines with access to free dental care. Materials and Methods: A total of 709 questionnaires were filled out. Data collected included: demographic data, oral health knowledge, and self-reported oral health practices and dental service utilization. Descriptive statistics and Chi-square analysis were performed; significance level was set at P < 0.05. Mean age was 20.8 ± 1.5 years. Results: There were (90.1%) of students who considered the toothbrush an oral hygiene aid, (91.1%) thought fluoride was beneficial to teeth, and almost (80%) students believed smoking has harmful effects on oral health. Regarding oral health practices, nearly half of the samples reported twice daily tooth-brushing, one-third received regular dental check-ups, and half visited the dentist because of pain or bleeding gums; fear was the main reason for not visiting the dentist. Females primarily visited the dentist for esthetic reasons (70%) and males upon complaint (59.8%). Oral health knowledge and practices among university students were poor. Conclusion: Dental students showed higher knowledge and better practices among disciplines studied. It is also important that dental hygienists take an active role in educating students in the aspect of oral health.
Comparison of a New Magnetic Resonance Imaging Protocol and Magnetic Resonance Follow-Through in Patients with Inflammatory Bowel Disease—A Prospective Pilot Study  [PDF]
Kayalvily Jesuratnam-Nielsen, Vibeke B. L?gager, Pia Munkholm, Yousef W. Nielsen, Henrik S. Thomsen
Open Journal of Radiology (OJRad) , 2015, DOI: 10.4236/ojrad.2015.52018
Abstract: Objective: Inflammatory bowel disease (IBD) is a chronic disease, consisting of two main subgroups: Crohn’s disease (CD) and ulcerative colitis (UC). Imaging is an essential component in the treatment of IBD and is used repeatedly to determine activity and severity of inflammatory lesions. The aim of our study was to prospectively obtain pilot data on the accuracy of magnetic resonance imaging with no oral contrast (MRI-NOC) and magnetic resonance follow-through (MRFT) using endoscopy as the reference standard. Materials and Methods: Patients diagnosed with CD and UC referred to magnetic resonance imaging (MRI) were included in this study population. For the evaluation, the bowel was divided into 9 segments. Two radiologists, blinded to clinical findings, evaluated bowel wall thickness, diffusion weighted imaging and mural hyperenhancement. Results: 14 patients (9 males and 5 females; median age 41; range 20 - 62) underwent both type of MRI examinations; 9 had CD and 5 had UC. The overall sensitivity for small bowel was zero for both MRI protocols, as neither identified any lesions, whereas in colon the sensitivity ranged from 7% to 29% in MRI-NOC and 14% - 29% in MRFT. Specificity and accuracy in MRI-NOC ranged from 78% to 98% and 74% - 93%, respectively, in small bowel, and from 90% to 96% and 77% - 82%, respectively, in colon. Specificity and accuracy in MRFT ranged from 83% to 100% and 79% - 95%, respectively, in small bowel, while it ranged from 93% to 97% and 81% - 85%, respectively, in colon. Conclusion: The location of lesions in the colon combined with the lack of oral contrast in the colon renders MRFT and MRI-NOC functionally identical.
Synthesis of Ba0.5Sr0.5Co0.2Fe0.8O3 (BSCF) Nanoceramic Cathode Powders by Sol-Gel Process for Solid Oxide Fuel Cell (SOFC) Application  [PDF]
Mohammad Ghouse, Yousef M. Al-Yousef
World Journal of Nano Science and Engineering (WJNSE) , 2011, DOI: 10.4236/wjnse.2011.14016
Abstract: The nano ceramic Ba0.5Sr0.5Co0.2Fe0.8O3 (BSCF) powders have been synthesized by Sol-Gel process using nitrate based chemicals for SOFC applications since these powders are considered to be more promising cathode materials for SOFC. Glycine was used as a chelant agent and ethylene glycol as a dispersant. The powders were calcined at 850℃/3 hr in the air using Thermolyne 47,900 furnace. These powders were characterized by employing SEM/EDS, XRD and TGA/DTA techniques. The SEM images BSCF powder indicate the presence of highly porous spherical particles with nano sizes. The XRD results shows the formation of BSCF perovskite phase at the calcination temperature of 850℃. From XRD line broadening technique, the average crystllite size of the BSCF powders were found to be around 9.15 - 11.83 nm and 13.63 - 17.47 nm for as prepared and after calcination at 850℃ respectively. The TGA plot shows that there is no weight loss after the temperature around 450℃ indicating completion of combustion.
Dyslipidemia and lipid peroxidation of Saudi type 2 diabetics with proliferative retinopathy
Yousef H. Aldebasi,Abdelmarouf H. Mohieldien,Yousef S. Almansour,Barakat L. Almutairi
Saudi Medical Journal , 2013,
Abstract: Objectives: To assess lipid profile and lipid peroxidation in type 2 diabetics with proliferative retinopathy (PDR), and investigate the association between these biochemical parameters and PDR. Methods: This study was conducted between June 2011 and February 2012 in the Research Laboratory, College of Applied Medical Sciences, Qassim University, Qasssim, Kingdom of Saudi Arabia. The study included 54 patients with type 2 diabetes (21 with PDR and 33 controls) and 30 healthy subjects. The biochemical parameters were measured using standard laboratory procedures. Results: Patients with PDR characterized by significantly (p<0.05) increased levels of serum cholesterol, triglyceride, low density lipoprotein (LDL-C), plasma malondialdehyde; decreased levels of serum high density lipoprotein (HDL-C) and apolipoprotein A1 (Apo A1); positive correlation of malondialdehyde with triglyceride, but negative with HDL-C, Apo A1. In logistic regression, malondialdehyde, LDL-C, and Apo A1 were not associated with PDR. However, triglyceride (OR = 1.745; p=0.000), total cholesterol (OR = 0.079; p=0.000), and HDL-C (OR = 10.676; p=0.000) were independent risk factors for developing PDR. Conclusion: Dyslipidemia and lipid peroxidation may play a role in pathogenesis of diabetic retinopathy. Patients with PDR displayed marked lipid abnormalities and increased lipid peroxidation. The control of lipid alterations through glycemic control and/or lipid lowering medication is required for type 2 diabetics at least to postpone or prevent loss of vision from retinopathy.
Investigation on Tabriz University Teachers’ Experiences of the Ignored Curriculumin General Courses  [PDF]
Yousef Rezapour, Sajjad Purbaghban
Open Journal of Applied Sciences (OJAppS) , 2014, DOI: 10.4236/ojapps.2014.46035
Abstract: The ignored curriculum is one of important elements in the curriculum that the design of this concept has led to reduce a superficial look at measures to curriculum. Ignored curriculum not only in the design but also should be considered at the implementation level. The present study examined the experiences of teachers in general education from ignored curriculum in higher education and this study was done by qualitative research and its approach was interpretive phenomenology. In this regard, semi-structured interviews were conducted with twenty-six teachers of general education courses and the data obtained from these interviews were analyzed by using phenomenology of Smith. Three major themes from ignored curriculum, were found from the experience of teachers including 1) lack of attention to requirements which consists of three sub-categories: in attention to the needs of the learner, the needs and demands of everyday life and the needs of experts; 2) lack of attention to content; 3) run into problems involving the four sub-problems of teaching, evaluation time, space and assessment. The teachers during the training and implementing courses have gained a lot of experience from the ignored curriculum that had impact on their perception. Planners are familiar with academics experiences and identify ignored curriculum of general education courses and emphasized on how they understand the main goals of general education courses and made it meaningful and they had a main role in eliminating the flaws of this course, and enhance the effectiveness of them. In summary, the results obtained from the study were that general education courses, do not address the needs of learners. These requirements include of three sub-categories: inattention to the needs of the learner, routine needs and professionals. Also, courses have less attention to content. And there are problems such as difficulties in teaching this lesson, time, space and evaluation.
Triangle of Safety Technique: A New Approach to Laparoscopic Cholecystectomy
Abdulrahman F. M. S. Almutairi,Yousef A. M. S. Hussain
HPB Surgery , 2009, DOI: 10.1155/2009/476159
Abstract: Backgrounds and Study Aims. Common bile duct (CBD) injury is one of the most serious complications of laparoscopic cholecystectomy (LC). Misidentification of the CBD during dissection of the Calot's triangle can lead to such injuries. The aim of the authors in this study is to present a new safe triangle of dissection. Patients and Method. 501 patients under went LC in the following approach; The cystic artery is identified and mobilized from the gall bladder (GB) medial wall down towards the cystic duct which would simultaneously divide the medial GB peritoneal attachment. This is then followed by dividing the lateral peritoneal attachment. The GB will be unfolded and the borders of the triangle of safety (TST) are achieved: cystic artery medially, cystic duct laterally and the gallbladder wall superiorly. The floor of the triangle is then divided to delineate both cystic duct and artery in an area relatively far from CBD. Results. There were little significant immediate or delayed complications. The mean operating time was 68 minutes, nearly equivalent to the conventional method. Conclusions. Dissection at TST appears to be a safe procedure which clearly demonstrates the cystic duct and may help to reduce the CBD injuries.
第1页/共324654条
每页显示


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.