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排序方式: 共有1811条查询结果,搜索用时 15 毫秒
91.
Azza Farrag Sameh Bakhoum Mohammed Ali Salem Amr El-Faramawy Emmanuel Gergis 《Heart and vessels》2013,28(1):12-18
Cardiovascular complications are the major cause of diabetes-associated morbidity and mortality. However, not all patients with diabetes are at increased risk for cardiovascular disease (CVD). Coronary artery calcification was found to be a powerful predictor of coronary artery disease (CAD). The presence of extracoronary cardiac calcification as a useful predictor of CAD is not yet established, especially in type 2 diabetes mellitus (T2DM). The aim of this study was to evaluate the relation between extracoronary calcification and extent of CAD in a group of T2DM patients who were scheduled for computed tomographic coronary angiography (CTCA). We prospectively studied 380 patients (151 had T2DM) under the age of 60 years who were scheduled for CTCA because of suspected CAD. Severity of CAD was assessed by Gensini score. Coronary artery calcium score (CACS) as well as calcium score in the aortic valve, mitral annulus, ascending aorta, and descending aorta were measured by a 256-row multidetector computed tomography scanner with dedicated software for calcium calculation. Patients with known CAD were excluded. Diabetic and nondiabetic patients had comparable age and gender distribution. However, the diabetic group had higher Gensini score, CACS, and extracoronary calcium score (ECCS). Logistic regression analyses identified male gender and ECCS as significant predictors for the presence of CAD in diabetic patients. Age, smoking, and ECCS were the significant predictors of CAD in nondiabetic patients. Type 2 diabetic patients had increased coronary and extracoronary calcification. ECCS was found to be a significant predictor of CAD in diabetic and nondiabetic patients only when CACS was not taken into account. 相似文献
92.
Mohamed Aboel-Kassem F Abdelmegid Mohamed M Bakr Hamdy Shams-Eddin Amr A Youssef Ahmed Abdel-Galeel 《World journal of cardiology》2023,15(3):106-115
BACKGROUND Myocardial ischemia and ST-elevation myocardial infarction(STEMI) increase QT dispersion(QTD) and corrected QT dispersion(QTcD), and are also associated with ventricular arrhythmia.AIM To evaluate the effects of reperfusion strategy [primary percutaneous coronary intervention(PPCI) or fibrinolytic therapy] on QTD and QTcD in STEMI patients and assess the impact of the chosen strategy on the occurrence of in-hospital arrhythmia.METHODS This prospective, observational, multicenter study... 相似文献
93.
Water desalination via solar steam generation is one of the most important technologies to address the increasingly pressing global water scarcity. Materials for solar photothermal energy conversion are highly sought after for their cost savings, environmental friendliness and broad utility in many applications including domestic water heating and solar-driven desalination. Herein, we report the successful development of metal-free, low weight and cost effective functionalized carbonized cotton (CC) fibers for efficient solar water desalination and wastewater treatment. The CC fibers with nearly full solar spectrum absorption, efficient photo-thermal conversion and low-cost could provide excellent alternatives to the high-cost plasmonic-based materials for solar water desalination. We also report on a novel and simple device to mitigate the issues associated with conductive heat loss by utilizing the economically viable carbonized cotton materials as an irradiation surface placed on a low-density polyethylene foam that floats on the surface of seawater. The CC solar steam generation device exhibits average water evaporation rates of 0.9, 6.4 and 10.9 kg m−2 h−1 with impressive solar-to-vapor efficiencies of 59.2, 88.7 and 94.9% under 1, 5 and 8 sun illumination, respectively. Moreover, the device displays excellent durability showing stable evaporation rates over 10 steam generation cycles under 5 sun of solar intensity. Furthermore, the applicability of the CC device for the removal of organic dyes from contaminated water through solar steam generation is also demonstrated. The low-cost, simple design, high solar thermal evaporation efficiency, excellent stability and long-term durability make this CC device a perfect candidate for applications in seawater desalination and wastewater treatment by solar steam generation.Water desalination via solar steam generation is one of the most important technologies to address the increasingly pressing global water scarcity. 相似文献
94.
Hisham S. M. Abd-Rabboh Abd El-Galil E. Amr Ahmed M. Naglah Abdulrahman A. Almehizia Ayman H. Kamel 《RSC advances》2021,11(61):38774
All-solid state screen-printed electrodes were fabricated for chlorogenic acid (CGA) detection. The screen-printed platforms were modified with multi-walled carbon nanotubes (MWCNTs) to work as a lipophilic solid-contact transducer. The sensing-membrane was plasticized with a suitable solvent mediator and incorporating [NiII(bathophenanthroline)3][CGA]2 complex as a sensory material. In a 30 mM phosphate solution (buffer, pH 6), the sensor revealed a Nernstian-response towards CGA ions with a slope of −55.1 ± 1.1 (r2 = 0.9997) over the linear range 1.0 × 10−7 to 1.0 × 10−3 (0.035–354.31 μg mL−1) with a detection limit 7.0 × 10−8 M (24.8 ng mL−1). It revealed a stable potentiometric response with excellent reproducibility and enhanced selectivity over several common ions. Short-term potential stability and the interfacial sensor capacitance was estimated using both electrochemical-impedance spectroscopy (EIS) and chronopotentiometry techniques. The presented electrochemical platform revealed the merits of design simplicity, ease of miniaturization, good potential-stability, and cost-effectiveness. It is successfully applied to CGA determination in different coffee beans extracts and juice samples. The data obtained were compared with those obtained by liquid chromatography reference method (HPLC).All-solid state screen-printed electrodes were fabricated for chlorogenic acid (CGA) detection. 相似文献
95.
Hisham S. M. Abd-Rabboh Abd El-Galil E. Amr Elsayed A. Elsayed Ahmed Y. A. Sayed Ayman H. Kamel 《RSC advances》2021,11(20):12227
Robust, reliable and cost-effective paper-based analytical device for potentiometric pholcodine (opiate derivative drug) ion sensing has been prepared and characterized. A printed pholcodinium (PHL)2+/5-nitrobarbiturate (NB)− ion-association complex as a sensory material-based all-solid-state ion-selective electrode (ISE) on a chemically reduced graphene oxide (CRGO) solid-contact, and a printed all-solid-state Ag/AgCl reference electrode, has been combined on a hydrophobic paper substrate coated with fluorinated alkyl silane (CF3(CF2)7CH2CH2SiCl3, CF10). The sensors revealed a potentiometric slope of 28.7 ± 0.3 mV dec−1 (R2 = 0.9998) over a linear range starting from 2.0 × 10−7 M to 1.0 × 10−2 M and a detection limit of 0.04 μg mL−1. The repeatability and stability of the pholcodine paper-based sensor was found to be 2.32%. The RSD% (n = 6) was found to be 2.67% when using five different paper-based sensors. The sensor revealed an excellent selectivity towards PHL over dextromethorphan, codeine, ephedrine, carbinoxamine, caffeine, ketamine, and K+, Na+ and Ca2+ ions. It showed a good recovery (94–104%) for the determination of PHL in different artificial serum samples. The presented paper-based analytical device was successfully introduced for PHL determination in different pharmaceutical formulations (i.e. syrups and suspensions) containing pholcodine. The current work can be considered as a promising possible analytical tool to obtain cost-effective and disposable paper-based potentiometric sensing devices. These devices can be potentially manufacturable at large scales in pharmaceutical, clinical and forensic applications for opiate drug assessment.Robust, reliable and cost-effective paper-based analytical device for potentiometric pholcodine (opiate derivative drug) ion sensing has been prepared and characterized. 相似文献
96.
Randomized Pilot Study of 20 Gy in 5 Fractions versus 27 Gy in 3 Fractions Radiotherapy for Treating Painful Bone Metastases: A Single Institution Experience 下载免费PDF全文
Amr SakrWedad Bassam HashemNadia EbrahimKarim Nabil Mashhour 《Asian Pacific journal of cancer prevention》2020,21(6):1807-1811
Purpose: Radiotherapy is a very effective tool in the treatment of painful bone metastases. The aim of this study was to compare the palliative effect of radiotherapy between the standard fractionation schedule 20 Gy over 5 fractions (20Gy/5fr) and the high biological dose schedule 27 Gy over 3 fractions (27Gy/3fr) which is frequently used in Stereotactic body radio-surgery (SBRT). Methods: Patients were randomized to receive (20Gy/5fr)or (27Gy/3fr). The primary aim of the study was pain relief using the numeric rating scale (NRS), after three months of radiation therapy. Secondary end points include pain relief immediately after finishing radiation therapy (within one week), and narcotic relief after three months of radiation therapy. Results: Twenty-two patients with painful bone metastases were included. 12 patients received (20Gy/5fr) and 10 patients received (27Gy/3fr). Male patients were predominant on both arms (81.8%) with a mean age of 58 years [ranging between 19-72 years]. For pain relief after three months of radiation therapy, partial pain relief was documented in 9 patients (75%) with (20Gy/5fr) and in 8 patients (80%) with (27Gy/3fr) with a p- value of 0.6. Additionally, narcotic relief after three months was equal for both groups. For immediate pain relief, partial pain relief was seen in one patient (8%) with (20Gy/5fr) versus seven patients (70%) with (27Gy/3fr) with a p value of 0.06. The increase in immediate pain relief in the 27Gy arm was numerically but not statistically significant. Conclusion: SBRT and standard fractionation radiation therapy had equal effectiveness for pain relief, when the assessment was done after three months of radiation therapy. Interestingly, SBRT had a better immediate pain relief. 相似文献
97.
High throughput tissue microarray analysis of FHIT expression in diffuse large cell B-cell lymphoma from Saudi Arabia. 总被引:1,自引:0,他引:1
Khawla Al Kuraya Abdul Khalid Siraj Prashant Bavi Naif Al-Jomah Hassan El-Solh Adnan Ezzat Fouad Al-Dayel Asim Belgaumi Amani Al-Kofide Rajeh Sabbah Salwa Sheikh Samir Amr Ronald Simon Guido Sauter 《Modern pathology》2006,19(8):1124-1129
Recent studies have suggested a potential prognostic role of alterations of the fragile histidine triad (FHIT) gene in diffuse large B-cell lymphoma. To evaluate possible mechanisms of FHIT inactivation and to further clarify its potential prognostic relevance, we analyzed a set of 114 diffuse large B-cell lymphoma with clinical follow-up information. Tissue microarrays were analyzed by immunohistochemistry for protein expression, and corresponding DNA samples were analyzed for FHIT promotor hypermethlyation. Reduced or absent FHIT expression was found in 75 of 114 diffuse large B-cell lymphoma (66%), but was unrelated to clinical tumor stage or patient prognosis. FHIT promotor hypermethylation was observed in 29 of 93 (23%) interpretable diffuse large B-cell lymphoma. Hypermethylation was not significantly correlated to protein expression loss, which could be explained by competing mechanisms for FHIT inactivation in a substantial fraction of non FHIT hypermethylated diffuse large B-cell lymphoma. Hypermethylation was significantly associated with poor prognosis of diffuse large B-cell lymphoma patients and predominantly seen in nongerminal center diffuse large B-cell lymphoma (27%), but less frequent (13%) in germinal center diffuse large B-cell lymphoma. In summary, these data suggest that promotor hypermethylation is responsible for reduced FHIT expression in a substantial subset of diffuse large B-cell lymphoma, which is primarily composed of nongerminal center subtype with poor patient prognosis. 相似文献
98.
Aliaa Amr Alamoudi Basem Salama El-Deek Yoon Soo Park Lana Adey Al Shawwa Ara Tekian 《Medical teacher》2017,39(3):S45-S49
AbstractPurpose: Evaluating the long-term impact of faculty development programs (FDPs) can help monitor the effectiveness of the program and identify areas for development. This study examined long-term differences in confidence, knowledge, behaviors, and policies of faculty members who attended FDPs on multiple choice question (MCQ) item analysis and faculty members who did not attend the FDPs.Methods: A cross-sectional study design was used, by administering a 24-item survey to a representative sample (simple random selection) of 61 faculty members at King Abdulaziz University Faculty of Medicine.Results: Among respondents, 34% did not attend FDPs; 53% attended 1–3 FDPs; and 13% attended more than 3 FDPs on MCQ item analysis. Results showed that faculty knowledge on elements of MCQ item analysis was significantly greater (p?=?.01) for members who attended the FDPs. Faculty who attended FDPs on MCQ item analysis were twice more likely to conduct item analysis in general (p?=?.020) and four times more likely to conduct item analysis for more than 70% of module examinations (p?=?.005).Conclusion: FDPs focused on MCQ item analysis can yield systematic changes on faculty confidence, knowledge, and behaviors. Moreover, FDPs also need support from the department and need sustained strategic support to ensure continued effectiveness. 相似文献
99.
Ketamine hydrochloride as sole anesthetic for open liver biopsy 总被引:1,自引:0,他引:1
A Abu Khalaf M Takrouri A Toukan M Abu Khalaf S Amr 《Middle East journal of anesthesiology》1988,9(6):537-543
We evaluated the use of ketamine as sole anesthetic agent for open liver biopsy, with particular reference to its effect on liver function and hepatotoxicity and its effect on cardiovascular stability and respiration. From 386 patients who underwent liver biopsy at Jordan University Hospital, 12 had open liver biopsy because of contra-indications for closed needle biopsy. The surgical procedure consisted of a small right paramedian incision allowing inspection of the liver surface and a wedge and needle biopsy. Ketamine HCl was used in a dose of 2 mg/kg I.V. with supplemental doses as necessary. No significant fluctuations in cardio-respiratory vital signs were observed. Muscle rigidity and respiratory tagging movements necessitated addition of a muscle relaxant and artificial ventilation in three patients. Six patients reported dreams, two of which were described as nightmares. There was no liver function decompensation, or significant bilirubin or transaminase elevations in the week following the biopsy. Ketamine is a safe anesthetic to use for open liver biopsy in patients with underlying liver disease, although poor muscle relaxation and nightmares may be significant side effects. 相似文献
100.