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991.
Hanan E. Shamseldin Ranad Shaheen Nour Ewida Dalal K. Bubshait Hisham Alkuraya Elham Almardawi Ali Howaidi Yasser Sabr Ebtesam M. Abdalla Abdullah Y. Alfaifi Jameel Mohammed Alghamdi Afaf Alsagheir Ahmed Alfares Heba Morsy Maged H. Hussein Mohammad A. Al-Muhaizea Mohammad Shagrani Essam Al Sabban Fowzan S. Alkuraya 《Genetics in medicine》2022,24(4):966
992.
Faleh Tamimi Jesus Torres Khadijeh Al-Abedalla Enrique Lopez-Cabarcos Mohammad H. Alkhraisat David C. Bassett Uwe Gbureck Jake E. Barralet 《Biomaterials》2014
Onlay grafts made of monolithic microporous monetite bioresorbable bioceramics have the capacity to conduct bone augmentation. However, there is heterogeneity in the graft behaviour in vivo that seems to correlate with the host anatomy. In this study, we sought to investigate the metabolic activity of the regenerated bone in monolithic monetite onlays by using positron emission tomography–computed tomography (PET-CT) in rats. This information was used to optimize the design of monetite onlays with different macroporous architecture that were then fabricated using a 3D-printing technique. In vivo, bone augmentation was attempted with these customized onlays in rabbits. PET-CT findings demonstrated that bone metabolism in the calvarial bone showed higher activity in the inferior and lateral areas of the onlays. Histological observations revealed higher bone volume (up to 47%), less heterogeneity and more implant osseointegration (up to 38%) in the augmented bone with the customized monetite onlays. Our results demonstrated for the first time that it is possible to achieve osseointegration of dental implants in bone augmented with 3D-printed synthetic onlays. It was also observed that designing the macropore geometry according to the bone metabolic activity was a key parameter in increasing the volume of bone augmented within monetite onlays. 相似文献
993.
Khondakar Mohammad Salah Uddin Mohammadreza Izadifar Neven Ukrainczyk Eduardus Koenders Bernhard Middendorf 《Materials》2022,15(4)
The current contribution proposes a multi-scale bridging modeling approach for the dissolution of crystals to connect the atomistic scale to the (sub-) micro-scale. This is demonstrated in the example of dissolution of portlandite, as a relatively simple benchmarking example for cementitious materials. Moreover, dissolution kinetics is also important for other industrial processes, e.g., acid gas absorption and pH control. In this work, the biased molecular dynamics (metadynamics) coupled with reactive force field is employed to calculate the reaction path as a free energy surface of calcium dissolution at 298 K in water from the different crystal facets of portlandite. It is also explained why the reactivity of the (010), (100), and (10) crystal facet is higher compared to the (001) facet. In addition, the influence of neighboring Ca crystal sites arrangements on the atomistic dissolution rates is explained as necessary scenarios for the upscaling. The calculated rate constants of all atomistic reaction scenarios provided an input catalog ready to be used in an upscaling kinetic Monte Carlo (KMC) approach. 相似文献
994.
Hossein Abdolrahimzadeh Fard Salahaddin Mahmudi-Azer Qusay Abdulzahraa Yaqoob Golnar Sabetian Pooya Iranpour Zahra Shayan Shahram Bolandparvaz Hamid Reza Abbasi Shiva Aminnia Maryam Salimi Mohammad Mehdi Mahmoudi Shahram Paydar Roham Borazjani Ali Taheri Akerdi Masome Zare Leila Shayan Mohammadreza Sasani 《中华创伤杂志(英文版)》2022,25(3):170-176
ProposeIn this study, we re-assessed the criteria defined by the radiological society of North America (RSNA) to determine novel radiological findings helping the physicians differentiating COVID-19 from pulmonary contusion.MethodsAll trauma patients with blunt chest wall trauma and subsequent pulmonary contusion, COVID-19-related signs and symptoms before the trauma were enrolled in this retrospective study from February to May 2020. Included patients (Group P) were then classified into two groups based on polymerase chain reaction tests (Group Pa for positive patients and Pb for negative ones). Moreover, 44 patients from the pre-pandemic period (Group PP) were enrolled. They were matched to Group P regarding age, sex, and trauma-related scores. Two radiologists blindly reviewed the CT images of all enrolled patients according to criteria defined by the RSNA criteria. The radiological findings were compared between Group P and Group PP; statistically significant ones were re-evaluated between Group Pa and Group Pb thereafter. Finally, the sensitivity and specificity of each significant findings were calculated. The Chi-square test was used to compare the radiological findings between Group P and Group PP.ResultsIn the Group PP, 73.7% of all ground-glass opacities (GGOs) and 80% of all multiple bilateral GGOs were detected (p < 0.001 and p = 0.25, respectively). Single bilateral GGOs were only seen among the Group PP. The Chi-square tests showed that the prevalence of diffused GGOs, multiple unilateral GGOs, multiple consolidations, and multiple bilateral consolidations were significantly higher in the Group P (p = 0.001, 0.01, 0.003, and 0.003, respectively). However, GGOs with irregular borders and single consolidations were more significant among the Group PP (p = 0.01 and 0.003, respectively). Of note, reticular distortions and subpleural spares were exclusively detected in the Group PP.ConclusionWe concluded that the criteria set by RSNA for the diagnosis of COVID-19 are not appropriate in trauma patients. The clinical signs and symptoms are not always useful either. The presence of multiple unilateral GGOs, diffused GGOs, and multiple bilateral consolidations favor COVID-19 with 88%, 97.62%, and 77.7% diagnostic accuracy. 相似文献
995.
Mohammad Kh. Alzawahreh Ala'a B. AlTammemi Mustafa I. AlShalah Ahmad Abuebeid Zaid Manaserh Baha'a Alhroub Moath O. Badawi Anas M. AbuZanouneh Maen Malkawi 《Clinical Case Reports》2022,10(3)
Giant Multilocular Prostatic Cystadenoma (GMPC) is one of the rare benign tumors of the prostate. This report presents a case of a young man who has been recently diagnosed with GMPC. Our report highlights the importance of timely diagnosis and treatment, considering the overlapping symptoms with other common urinary conditions. 相似文献
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999.
Negahban H Mofateh R Arastoo AA Mazaheri M Yazdi MJ Salavati M Majdinasab N 《Gait & posture》2011,34(4):479-484
The aim of this study was to compare the effects of concurrent cognitive task (silent backward counting) on balance performance between two groups of multiple sclerosis (MS) (n = 23) and healthy (n = 23) participates. Three levels of postural difficulty were studied on a force platform, i.e. rigid surface with eyes open, rigid surface with eyes closed, and foam surface with eyes closed. A mixed model analysis of variance showed that under difficult sensory condition of foam surface with eyes closed, execution of concurrent cognitive task caused a significant decrement in variability of sway velocity in anteroposterior direction for the patient group (P < 0.01) while this was not the case for healthy participants (P = 0.22). Also, the variability of sway velocity in mediolateral direction was significantly decreased during concurrent execution of cognitive task in patient group (P < 0.01) and not in healthy participants (P = 0.39). Furthermore, in contrast to single tasking, dual tasking had the ability to discriminate between the 2 groups in all conditions of postural difficulty. In conclusion, findings of variability in sway velocity seem to confirm the different response to cognitive loading between two groups of MS and healthy participants. 相似文献
1000.
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