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This study was aimed to evaluate different management modalities for peripheral vascular trauma in children, with the aid of the Mangled Extremity Severity Score (MESS). A single-center retrospective analysis took place between 2010 and 2017 at University Hospitals, having emergencies and critical care centers. Different types of vascular repair were adopted by skillful vascular experts and highly trained pediatric surgeons. Patients were divided into three different age groups. Group I included those children between 5 and 10 years; group II involved pediatrics between 11 and 15 years; while children between 16 and 21 years participated in group III. We recruited 183 children with peripheral vascular injuries. They were 87% males and 13% females, with the mean age of 14.72 ± 04. Arteriorrhaphy was performed in 32%; end-to-end anastomosis and natural vein graft were adopted in 18% and 29% respectively. On the other hand, 20% underwent bypass surgery. The age groups I and II are highly susceptible to penetrating trauma ( p  = 0.001), while patients with an extreme age (i.e., group III) are more susceptible to blunt injury ( p  = 0.001). The MESS has a significant correlation to both age groups I and II ( p  = 0.001). Vein patch angioplasty and end-to-end primary repair should be adopted as the main treatment options for the repair of extremity vascular injuries in children. Moreover, other treatment modalities, such as repair with autologous vein graft/bypass surgery, may be adopted whenever possible. They are cost-effective, reliable, and simple techniques with fewer postoperative complication, especially in poor/limited resources.  相似文献   
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A series of new fluoroquinolone conjugates 8a–g and 9a–f were synthesized via benzotriazole‐mediated synthetic approach with good yield and purity. Some of the synthesized analogs exhibited significant antibacterial properties against Escherichia coli and Staphylococcus aureus with potency higher than that of the parent drugs through in vitro standard bioassay procedure (conjugates 8c and 8d reveal antimicrobial properties with potency 1.9, 61.9, 20.7 and 2.4, 37.1, 8.3 folds relative to the parent antibiotic 6 against E. coli, S. aureus, and Enterococcus faecalis, respectively). The observed experimental data were supported by enzymatic DNA gyrase inhibitory property. Developed BMLR‐QSAR model validates the observed experimental data and recognizes the parameters responsible for the enhanced antibacterial properties.  相似文献   
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Herein, ethylenediamine functionalized porous carbon (PC-ED/1.5) was synthesized, then characterized by various methods and finally used as a functional material for Cu(ii) and Pb(ii) ion removal from water. XPS revealed the presence of numerous functionalities within the surface of PC including –NH and C–N–C groups. Furthermore, SBET, RS, XRD and FTIR analyses confirmed the changes implemented on the PC surface. Thereafter, a systematic study was implemented to analyze the interactions of the PC-ED/1.5 surface with Cu(ii) and Pb(ii) heavy metal ions. Hence, adsorption experiments showed that the PC-ED/1.5 exhibits maximum adsorption capacities of 123.45 mg g−1 and 140.84 mg g−1 for Cu(ii) and Pb(ii), respectively. Moreover, in situ electrostatic interactions occurring between the divalent cation and the PC-ED/1.5 functional groups was investigated. The mechanism involves chelation processes, electrostatic interactions and mechanical trapping of the metal ions in the adsorbent pores. Interestingly, a synergistic effect of the pores and surface active sites was observed. Finally, by using alginate bio-polymer we prepared membrane films of PC-ED/1.5 which showed long-term stability, regeneration capabilities and high mass recovery.

Herein, ethylenediamine functionalized porous carbon (PC-ED/1.5) was synthesized, then characterized by various methods and finally used as a functional material for Cu(ii) and Pb(ii) ion removal from water.  相似文献   
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Objectives:To evaluate the impact of coronavirus-19 (COVID-19) pandemic and its consequences on general surgery residents.Methods:Cross-sectional, survey based study including surgical residents in Kingdom of Saudi Arabia and Kingdom of Bahrain.Results:Surgical trainees who participated in our survey (n=234) were young (mean age 28), single (53.8%), and males (65.8%). Approximately half (50.4%) have been deployed to cover the staff shortage in intensive care units (ICUs) or emergency departments (EDs). Half of our trainees (117) scored positive in the screening tool of generalized anxiety disorder (GAD). There was a significant association between experiencing anxiety and male gender (p=0.055), level of training (p=0.002), deployment to cover ICUs (p=0.050), testing positive for COVID-19 (p=0.054) and having an infected family member (p=0.004).Conclusion:Coronavirus-19 pandemic has a serious effect on all healthcare workers and surgical residents have experienced a considerable amount of stress. Accordingly, this psychological burden should be appropriately addressed in organizations planning strategies. We suggest formulating guidelines to help surgical trainees to continue their learning process with least psychological burden.  相似文献   
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