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排序方式: 共有3175条查询结果,搜索用时 31 毫秒
91.
Ramy F. Youssef Shahrokh F. Shariat Yair Lotan Nicholas Cost Christopher G. Wood Arthur I. Sagalowsky Richard Zigeuner Cord Langner Thomas F. Chromecki Francesco Montorsi Christian Bolenz Vitaly Margulis 《Urologic oncology》2013,31(5):676-681
ObjectiveThe natural history of urothelial carcinoma arising at the uretero-enteric junction (UEJ) is poorly defined, and the data guiding clinical management of these patients is limited. Therefore, we evaluated oncologic outcomes of patients treated for urothelial carcinoma at the UEJ.MethodsUtilizing a multi-institutional database of patients treated with radical nephroureterectomy (RNU), we assessed the clinicopathologic parameters and oncologic outcomes of UEJ tumors compared with other upper tract urothelial carcinomas (UTUC). Survival analyses were performed to determine independent predictors of disease recurrence and cancer-specific mortality after RNU.ResultsThe study included 1,363 patients, 921 men and 442 women with 36 months median follow-up after RNU. Compared with UTUC in the kidney or ureter, UEJ tumors (n = 22) were more likely to demonstrate features of advanced disease, which were proved to be independent predictors of disease recurrence and cancer-specific mortality after RNU. The 5 year disease-free survival (DFS) and cancer-specific survival (CSS) rates were 25% and 39% in those with UEJ tumors vs. 69% and 73% in those with UTUC in the kidney or ureter (P = 0.001 and P = 0.008, respectively).ConclusionsUEJ tumors harbor features of locally advanced disease associated with high risk of systemic recurrence and death from cancer after RNU. Our findings suggest the need for integration of systemic therapy into the management paradigm of these patients. 相似文献
92.
BackgroundSpinal anesthesia is gradually increasing in ambulatory setting. The limiting factor to the more widespread use of spinal anesthesia in the outpatient setting refers to the effect of residual block. Selective spinal anesthesia (SSA) with low dose lidocaine was compared with modern general anesthesia (GA) technique in day care anorectal surgeries.ObjectiveOur objectives in this study was to compare SSA with propofol and fentanyl based modern GA as regard to 1 – operating conditions 2 – patients’ and surgeon’s satisfaction, 3 – intraoperative, postoperative adverse events and 4 – recovery profiles in ambulatory anorectal surgeries.MethodsProspective randomized clinical study was conducted on 60 patients undergoing elective day case anorectal surgery. The patients were randomly allocated into one of two groups (GA and SSA groups) of 30 patients each. In GA group anesthesia was induced with intravenous fentanyl (2 μg/kg) and propofol (2–3 mg/kg). Airway was secured with I-gel supraglottic airway. Anesthesia was maintained by sevoflurane 1.5–2%, nitrous oxide 60% in oxygen mixture. SSA group patients received spinal anesthesia with lidocaine 20 mg and fentanyl 25 μg to a total volume of 3 ml with sterile water for injection. Intraoperative, postoperative and home adverse events, time to ambulate, time to home discharge, patients’ and surgeon’s satisfactions were statistically compared between both groups.ResultsBoth anesthetic techniques showed acceptable operating conditions and high rate of patients’ satisfaction. Low pain intensity, shorter time to ambulate and home discharge in SSA compared to GA with a p value < 0.001. Intraoperative hemodynamic stability was reported in both groups. No major postoperative or home adverse events in both groups.ConclusionsSSA with low dose lidocaine may be suitable alternative and competitive for modern GA in ambulatory anorectal surgery. 相似文献
93.
Humam Saltaji Michael P. Major Mostafa Altalibi Mohamed Youssef Carlos Flores-Mir 《The Angle orthodontist》2012,82(6):1115
Objective:To systematically review the long-term skeletal stability after maxillary advancement with distraction osteogenesis (DO) in cleft lip and palate (CLP) patients.Materials and Methods:Electronic databases, grey literature, and reference list searches were conducted. The inclusion criteria were stability of maxillary advancement with distraction osteogenesis assessed at the posttreatment follow-up ≥ 1 year in CLP patients. Full articles were retrieved from abstracts or titles that appear to meet the inclusion criteria or lacked sufficient detail for immediate exclusion. Once full articles were collected, they were again reviewed considering more detailed inclusion criteria for a final selection decision. A methodologic quality assessment tool was utilized.Results:Thirty abstracts/titles met the initial search criteria, and 13 articles were finally selected. Overall, methodologic quality scores were high in only one randomized clinical trial. After maxillary advancement with DO in CLP patients, the long-term horizontal relapse in A-point was less than 15% in eight studies and between 20% and 25% in four studies. The study that was judged as a high-quality study reported 8.2% horizontal relapse in A-point. The relapse rate was higher in DO with external distracter device than DO with internal distracter device.Conclusions:Current evidence suggests maxillary advancement with DO has good stability in CLP patients with moderate and severe maxillary hypoplasia. 相似文献
94.
Mahmoud Rafaat Kandil Kawthar Abdel-Motagally Fadel Hossam Eldin Khalifa Mostafa Kamel Ghanem Khaled Osama Mohamed 《Neurological research》2013,35(3):232-241
AbstractObjectives: Headache is one of the most common complaints in medicine. Epidemiological and population-based studies reported that migraine has a variable prevalence worldwide. This study was done to estimate the prevalence of migraine across various age groups in Assiut district, Egypt.Methods: This is a door-to-door study. It included 4700 randomly selected individuals.Results: Headache was reported in 1668 subjects (35.49%), of them, 87.65% (n = 1462) had primary headaches. Migraine prevalence was 10.51% with female-to-male ratio of 2.4:1 particularly in ages of 20–40 years. The mean age of patients was 31.46 ± 13.39 years and age at onset was 24.16 ± 12.10 years. Nearly, 63.5% had frequent attacks, 65.2% of the attacks were severe enough to stop daily activities and lasted for >1 day in 32.5% of females compared to 40.7% and 14.5% for males. Chronic or daily migraine was more in females (35.3% versus 20.7% for males). Approximately, 5.6% had chronic migraine and 1.2% had daily migraine from the start, while 24.2% had transformation from episodic to chronic migraine within 6.1 ± 4.4 years. Migraine was prevalent among those with middle educational levels and labor workers. The duration of migraine attacks was found to reduce with age but the chronic/daily migraine increased with age. Hypertension, anxiety, irritable bowel syndrome, and depression were common comorbidities with migraine.Conclusions: We believe that the work done in this study is informative as it determined the actual prevalence of migraine across various age groups and the important predictors of change in the severity, duration, and frequency of migraine in our locality. 相似文献
95.
Mustapha Alahiane Rachid Oukhrib Youssef Ait Albrimi Hicham Abou Oualid Hassan Bourzi Rachid Ait Akbour Ali Assabbane Ayssar Nahl Mohamed Hamdani 《RSC advances》2020,10(67):41137
The inhibition efficiency of benzoic acid (C1), para-hydroxybenzoic acid (C2), and 3,4-dihydroxybenzoic acid (C3) towards enhancing the corrosion resistance of austenitic AISI 316 stainless steel (SS) has been evaluated in 0.5 M HCl using weight loss (WL), open circuit potential (OCP), potentiodynamic polarization method, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM) analysis. The results obtained from the different experimental techniques were consistent and showed that the inhibition efficiency of these inhibitors increased with the increase in concentration in this order C3 > C2 > C1. In addition, the results of the weight loss measurements showed that these inhibitors followed the Villamil isotherm. Quantum chemical calculations and Monte Carlo simulations have also been used for further insight into the adsorption mechanism of the inhibitor molecules on Fe (110). The quantum chemical parameters have been calculated by density functional theory (DFT) at the B3LYP level of theory with 6-31G+(2d,p) and 6-31G++(2d,p) basis sets in gas and aqueous phase. Parameters such as the lowest unoccupied (ELUMO) and highest occupied (EHOMO) molecular orbital energies, energy gap (ΔE), chemical hardness (η), softness (σ), electronegativity (χ), electrophilicity (ω), and nucleophilicity (ε) were calculated and showed the anti-corrosive properties of C1, C2 and C3. Moreover, theoretical vibrational spectra were calculated to exhibit the functional hydroxyl groups (OH) in the studied compounds. In agreement with the experimental data, the theoretical results showed that the order of inhibition efficiency was C3 > C2 > C1.The corrosion inhibition efficiencies of benzoic acid (C1), para-hydroxybenzoic acid (C2), and 3,4-dihydroxybenzoic acid (C3) have been evaluated in 0.5 M HCl toward protecting AISI 316 stainless steel (SS). 相似文献
96.
Omar Ahmad Hassanien Rasha T. Abouelkheir Mohamed Ibrahim Abou El-Ghar Manal Ezzat Badawy Samir Abdel-hakim El Gamal Mohamed Abd El-Hamid 《Journal l'Association canadienne des radiologistes》2019,70(3):254-263
PurposeThe aim of study is to assess the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and correlation with tumour angiogenesis in evaluation of urinary bladder cancer.Material and MethodsThe study included 81 patients with recent presumed diagnosis of bladder tumour or who came for follow up after management of histopathologically proven bladder cancer. All had DCE-MRI with time–signal intensity curve. The radiologic results then correlated with the histopathologic results using both haematoxylin and eosin stain and immuno-histochemical staining for localization and evaluation of CD34 immunoreactivity as a detector for the microvessel density (MVD) and tumour angiogenesis.ResultsSeventy-one cases were pathologically proven to be malignant: 41 cases (58%) showed type III time–signal intensity curve (descending); 22 cases (31%) showed type II (plateau); and 8 cases (11%) showed type I (ascending) curve. The sensitivity of DCE-MRI in stage T1 bladder tumour was 80%; in stage T2, it was (90.9%); and in stage T3, it was (96.9%). Overall accuracy of DCE-MRI in tumour staging was 89.5% and P = .001 (significant). Values more than the cutoff value = 76.13 MVD are cystitis with sensitivity (90%), specificity (91%), and P value is .001, which is statistically highly significant.ConclusionThere is a strong positive association between DCE-MRI (staging and washout slope of the time–signal intensity curve) with histopathologic grade, tumour stage, and MVD in bladder cancer. So, DCE-MRI can be used as reliable technique in preoperative predictions of tumour behavior and affect the planning of antiangiogenetic therapy. 相似文献
97.
Alloush Taha K. Mansour Osama Alloush Adel T. Roushdy Tamer Hamid Eman El-Shamy Mahmoud Shokri Hossam M. 《Neurological sciences》2022,43(2):799-809
Neurological Sciences - COVID-19 is a pandemic disease which predominantly affects the respiratory system with high critical care mortality and morbidity; however, it also causes multi-organ... 相似文献
98.
Abram W. Makram Ayman M. Khalifa Hossam El-Rewaidy Ahmed S. Fahmy El-Sayed H. Ibrahim 《Japanese journal of radiology》2016,34(2):158-165
Purpose
Tagged and cine magnetic resonance imaging (tMRI and cMRI) techniques are used for evaluating regional and global heart function, respectively. Measuring global function parameters directly from tMRI is challenging due to the obstruction of the anatomical structure by the tagging pattern. The purpose of this study was to develop a method for processing the tMRI images to improve the myocardium-blood contrast in order to estimate global function parameters from the processed images.Materials and methods
The developed method consists of two stages: (1) removing the tagging pattern based on analyzing and modeling the signal distribution in the image’s k-space, and (2) enhancing the blood-myocardium contrast based on analyzing the signal intensity variability in the two tissues. The developed method is implemented on images from twelve human subjects.Results
Ventricular mass measured with the developed method showed good agreement with that measured from gold-standard cMRI images. Further, preliminary results on measuring ventricular volume using the developed method are presented.Conclusion
The promising results in this study show the potential of the developed method for evaluating both regional and global heart function from a single set of tMRI images, with associated reduction in scan time and patient discomfort.99.
100.
Chronic Mastitis in Egypt and Morocco: Differentiating between Idiopathic Granulomatous Mastitis and IgG4‐Related Disease 下载免费PDF全文