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61.
62.
Redha Mohammed Souilamas Mateen Haider Uzbeck Yusuf Bayrak Nacira Guenif Fadi Hamed Irfan Shafiq Vivek Kakar Mahmoud Elkaissi Hicham Abada Fadi Younes Ashraf Alzaabi Zaid Zoumot Ali Wahla 《Journal of thoracic disease》2022,14(3):788
The United Arab Emirates (UAE) has undergone a significant change in its population and economy in the last decades and in parallel its healthcare system has evolved rapidly to provide advanced, innovative and world-leading care. At the forefront of this revolution in healthcare is the development of a multidisciplinary multimodality thoracic service provision, offered at quaternary referral hospitals amalgamating academics, training, research and innovation. Previously, thoracic service care was limited to single providers at various public and private hospitals, usually performing lower complexity cases. Most complex thoracic cases were repatriated outside the UAE. This practice was replaced with the opening of Cleveland Clinic Abu Dhabi (CCAD), in 2015, which created a multidisciplinary thoracic program. This included the start of a mini-invasive surgical and lung transplantation program. Since that time other public and private hospitals have emerged providing care in a similar model. The impact of these programs has been a decreased transfer of patients abroad for treatment. Under the umbrella of the Emirates Thoracic Society (ETS) a platform for greater collaboration aimed at improving patient care, potential research and physician education has been created. Direct links have been established with world-leading Thoracic surgery and Respiratory Medicine Centers facilitating this development and offering support and guidance. This article charts these changes in thoracic care in the recent past, present, and delineates plans for the future in the UAE. 相似文献
63.
Azhar Equbal Mohammad Ali Md. Asif Equbal S. C. Srivastava Zahid A. Khan Md. Israr Equbal Irfan Anjum Badruddin Khalid Mohamed El-Hady Sarfaraz Kamangar 《Materials》2022,15(7)
In this study, compacted hematite (Fe2O3) preforms were made and sintered at various temperatures, such as 1250 °C and 1300 °C, using both conventional and microwave sintering methods. The density, porosity, microhardness, cold crushing strength, microphotographs, and X-ray diffraction (XRD) analysis of the sintered preforms were used to evaluate the performance of the two sintering methods. It was found that microwave sintered preforms possessed lesser porosity and higher density than conventionally sintered preforms owing to uniform heating of the powdered ore in microwave sintering method. Furthermore, it was also observed that microwave sintered preforms exhibited relatively higher cold crushing strength and hardness than conventionally sintered preforms. Thus, the overall results revealed that microwave sintering yielded better properties considered in the present study. 相似文献
64.
Oral contrast medium in PET/CT: should you or shouldn’t you? 总被引:2,自引:0,他引:2
Groves AM Kayani I Dickson JC Townsend C Croasdale I Syed R Nagabushan N Hain SF Ell PJ Bomanji JB 《European journal of nuclear medicine and molecular imaging》2005,32(10):1160-1166
Purpose It has been suggested that the use of computed tomography (CT) positive contrast agents has led to attenuation-induced artefacts on 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET/CT) systems. Consequently, centres may withhold the use of such agents. Whilst there is theoretical evidence to support the aforementioned claim, the clinical relevance of the induced artefacts has not been widely established. Moreover, the potential benefits of bowel enhancement on PET/CT have yet to be formally evaluated. We therefore prospectively examined PET/CT studies to assess whether the use of oral contrast medium induces clinically relevant artefacts and whether the use of these agents is diagnostically helpful.Methods Over a 2-month period, 18F-FDG PET/CT images were prospectively reviewed from 200 patients following Gastrografin administration 2 h prior to examination. Both a radiologist and a nuclear medicine physician reviewed the images for contrast medium-mediated clinically relevant artefacts. Artefacts were sought on the CT attenuation-corrected images and were compared with the appearance on non-attenuated-corrected images. The number of examinations in which the oral contrast aided image interpretation was also noted.Results There were no oral contrast medium-induced clinically significant artefacts. In 38 of the 200 patients, oral contrast aided image interpretation (owing to differentiation of mass/node from bowel, discrimination of intestinal wall from lumen or definition of the anatomy of a relevant site). In 33 of these 38 patients, the anatomical site of interest was the abdomen/pelvis.Conclusion The use of oral contrast medium in 18F-FDG PET studies should not be withheld as it improves image interpretation and does not produce clinically significant artefacts. 相似文献
65.
Mahmoud Elmalky Naveed Yasin Ricardo Rodrigues-Pinto John Stephenson Craig Carroll Glyn Smurthwaite Rajat Verma Saeed Mohammad Irfan Siddique 《The spine journal》2017,17(7):977-982
Background Context
Metastatic spine tumor surgery (MSTS) is associated with substantial blood loss, therefore leading to high morbidity and mortality. Although intraoperative cell salvage with leukocyte depletion filter (IOCS-LDF) has been studied as an effective means of reducing blood loss in other surgical settings, including the spine, no study has yet analyzed the efficacy of reinfusion of salvaged blood in reducing the need for allogenic blood transfusion in patients who have had surgery for MSTS.Purpose
This study aimed to analyze the efficacy, safety, and cost-effectiveness of using IOCS-LDF in MSTS.Study Design
This is a retrospective controlled study.Patient Sample
A total of 176 patients undergoing MSTS were included in the study.Methods
All patients undergoing MSTS at a single center between February 2010 and December 2014 were included in the study. The primary outcome measure was the use of autologous blood transfusion. Secondary outcome measures included hospital stay, survival time, complications, and procedural costs. The key predictor variable was whether IOCS-LDF was used during surgery. Logistic and linear regression analyses were conducted by controlling variables such as tumor type, number of diseased vertebrae, approach, number and site of stabilized segments, operation time, preoperative anemia, American Society of Anesthesiologists (ASA) grade, age, gender, and body mass index (BMI). No funding was obtained and there are no conflicts of interest to be declared.Results
Data included 63 cases (IOCS-LDF) and 113 controls (non–IOCS-LDF). Intraoperative cell salvage with LDF utilization was substantively and significantly associated with a lower likelihood of allogenic blood transfusion (OR=0.407, p=.03). Intraoperative cell salvage with LDF was cost neutral (p=.88). Average hospital stay was 3.76 days shorter among IOCS-LDF patients (p=.03). Patient survival and complication rates were comparable in both groups.Conclusions
We have demonstrated that the use of IOCS-LDF in MSTS reduces the need for postoperative allogenic blood transfusion while maintaining satisfactory postoperative hemoglobin. We recommend routine use of IOCS-LDF in MSTS for its safety, efficacy, and potential cost benefit. 相似文献66.
Is a T-tube Necessary after Common Bile Duct Exploration? 总被引:1,自引:0,他引:1
Ahmed I Pradhan C Beckingham IJ Brooks AJ Rowlands BJ Lobo DN 《World journal of surgery》2008,32(7):1485-1488
BACKGROUND: T-tube drainage used to be standard practice after surgical choledocholithotomy, but there is now a tendency in some centers to close the common bile duct (CBD) primarily. This study was designed to review the complications associated with T-tube drainage after CBD exploration and to determine whether primary closure of the bile duct reduces postoperative morbidity. METHODS: A retrospective audit was performed on patients undergoing CBD exploration between July 1997 and March 2007, who were identified from the theatre database of one teaching hospital. Intraoperative findings and postoperative complications were recorded from the clinical notes. RESULTS: During the study period, 158 patients (97 women; median age 65 (range, 25-90) years) underwent CBD exploration. A T-tube was inserted in 91 patients (group I) and the CBD was closed primarily in 67 (group II). One or more biliary complications occurred in 26 patients (16.5%): 20 (22.0%) in group I and 6 (8.9%) in group II (p = 0.03). In group I, 15 had a biliary leak (3 needed reoperation), 2 had accidental slippage of the tube, 2 an entrapped T-tube, and 1 a retained stone. In group II, six patients had biliary leakage, two of whom were re-explored. Six patients in group I also had peritubal infection, necessitating the use of antibiotics. There were three deaths: two in group I (1 T-tube-related) and 1 in group II (p = 1, not significant). CONCLUSION: There is a lower biliary complication rate associated with primary closure of the CBD than after T-tube drainage. 相似文献
67.
Mahmood Ahmad Ramez A. Al-Mansob Irfan Jamil Mohammad A. Al-Zubi Mohanad Muayad Sabri Sabri Arnold C. Alguno 《Materials》2022,15(5)
The mechanical behavior of the rockfill materials (RFMs) used in a dam’s shell must be evaluated for the safe and cost-effective design of embankment dams. However, the characterization of RFMs with specific reference to shear strength is challenging and costly, as the materials may contain particles larger than 500 mm in diameter. This study explores the potential of various kernel function-based Gaussian process regression (GPR) models to predict the shear strength of RFMs. A total of 165 datasets compiled from the literature were selected to train and test the proposed models. Comparing the developed models based on the GPR method shows that the superlative model was the Pearson universal kernel (PUK) model with an R-squared (R2) of 0.9806, a correlation coefficient (r) of 0.9903, a mean absolute error (MAE) of 0.0646 MPa, a root mean square error (RMSE) of 0.0965 MPa, a relative absolute error (RAE) of 13.0776%, and a root relative squared error (RRSE) of 14.6311% in the training phase, while it performed equally well in the testing phase, with R2 = 0.9455, r = 0.9724, MAE = 0.1048 MPa, RMSE = 0.1443 MPa, RAE = 21.8554%, and RRSE = 23.6865%. The prediction results of the GPR-PUK model are found to be more accurate and are in good agreement with the actual shear strength of RFMs, thus verifying the feasibility and effectiveness of the model. 相似文献
68.
Belay Brehane Tesfamariam Redeat Seyoum Dinsefa Mensur Andoshe Tatek Temesgen Terfasa Gulam Mohammed Sayeed Ahmed Irfan Anjum Badruddin H.M.T. Khaleed 《Materials》2022,15(5)
Cracks in typical mortar constructions enhance water permeability and degrade ions into the structure, resulting in decreased mortar durability and strength. In this study, mortar samples are created that self-healed their cracks by precipitating calcium carbonate into them. Bacillus subtilus bacterium (10−7, 10−9 cells/mL), calcium lactate, fine aggregate, OPC-cement, water, and bagasse ash were used to make self-healing mortar samples. Calcium lactates were prepared from discarded eggshells and lactic acid to reduce the cost of self-healing mortars, and 5% control burnt bagasse ash was also employed as an OPC-cement alternative. In the presence of moisture, the bacterial spores in mortars become active and begin to feed the nutrient (calcium lactate). The calcium carbonate precipitates and plugs the fracture. Our experimental results demonstrated that cracks in self-healing mortars containing bagasse ash were largely healed after 3 days of curing, but this did not occur in conventional mortar samples. Cracks up to 0.6 mm in self-healing mortars were filled with calcite using 10−7 and 10−9 cell/mL bacteria concentrations. Images from an optical microscope, X-ray Diffraction (XRD), and a scanning electron microscope (SEM) were used to confirm the production of calcite in fractures. Furthermore, throughout the pre- and post-crack-development stages, self-healing mortars have higher compressive strength than conventional mortars. The precipitated calcium carbonates were primed to compact the samples by filling the void spaces in hardened mortar samples. When fissures developed in hardened mortars, bacteria became active in the presence of moisture, causing calcite to precipitate and fill the cracks. The compressive strength and flexural strength of self-healing mortar samples are higher than conventional mortars before cracks develop in the samples. After the healing process of the broken mortar parts (due to cracking), self-healing mortars containing 5% bagasse ash withstand a certain load and have greater flexural strength (100 kPa) than conventional mortars (zero kPa) at 28 days of cure. Self-healing mortars absorb less water than typical mortar samples. Mortar samples containing 10−7 bacteria cells/mL exhibit greater compressive strength, flexural strength, and self-healing ability. XRD and SEM were used to analyze mortar samples with healed fractures. XRD, FTIR, and SEM images were also used to validate the produced calcium lactate. Furthermore, the durability of mortars was evaluated using DTA-TGA analysis and water absorption tests. 相似文献
69.
Muhammad Irfan Sharjeel Waqas Ushtar Arshad Javed Akbar Khan Stanislaw Legutko Izabela Kruszelnicka Dobrochna Ginter-Kramarczyk Saifur Rahman Anna Skrzypczak 《Materials》2022,15(5)
Membrane fouling is a major hindrance to widespread wastewater treatment applications. This study optimizes operating parameters in membrane rotating biological contactors (MRBC) for maximized membrane fouling through Response Surface Methodology (RSM) and an Artificial Neural Network (ANN). MRBC is an integrated system, embracing membrane filtration and conventional rotating biological contactor in one individual bioreactor. The filtration performance was optimized by exploiting the three parameters of disk rotational speed, membrane-to-disk gap, and organic loading rate. The results showed that both the RSM and ANN models were in good agreement with the experimental data and the modelled equation. The overall R2 value was 0.9982 for the proposed network using ANN, higher than the RSM value (0.9762). The RSM model demonstrated the optimum operating parameter values of a 44 rpm disk rotational speed, a 1.07 membrane-to-disk gap, and a 10.2 g COD/m2 d organic loading rate. The optimization of process parameters can eliminate unnecessary steps and automate steps in the process to save time, reduce errors and avoid duplicate work. This work demonstrates the effective use of statistical modeling to enhance MRBC system performance to obtain a sustainable and energy-efficient treatment process to prevent human health and the environment. 相似文献
70.
Ali Irfan Guzel Umur Kuyumcuoglu Yusuf Celik 《Archives of gynecology and obstetrics》2011,283(6):1227-1232