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排序方式: 共有3579条查询结果,搜索用时 46 毫秒
991.
Christine E. Lehman PhD Ashraf A. Khalil MD PhD Mark J. Axelrod PhD Michael I. Dougherty BA Stephen S. Schoeff MD Linnea E. Taniguchi MS Rolando E. Mendez BS Abel P. David MD Patrick O. McGarey Jr. MD Matthew A. Hubbard MD Lane Donaldson MD Henry F. Frierson Jr. MD Edward B. Stelow MD Stefan Bekiranov PhD Julia D. Wulfkuhle PhD Emanuel F. Petricoin PhD Daniel G. Gioeli PhD Mark J. Jameson MD PhD 《The Laryngoscope》2020,130(6):1470-1478
992.
Schmied MC Zehetmayer S Reindl M Ehling R Bajer-Kornek B Leutmezer F Zebenholzer K Hotzy C Lichtner P Meitinger T Wichmann HE Illig T Gieger C Huber K Khalil M Fuchs S Schmidt H Auff E Kristoferitsch W Fazekas F Berger T Vass K Zimprich A 《Neurogenetics》2012,13(2):181-187
We performed a replication study in 883 Austrian multiple sclerosis (MS) patients and 972 control individuals for 25 previously risk-associated loci (39 SNPs). Two loci, rs1109670 (DDEF2/MBOAT2, p?0.02) and rs16914086 (TBC1D2, p?0.05), are replicated here for the first time. Furthermore, we tested all 39 SNPs for association with age at disease onset and measures of disease severity. We observed a trend for association of rs3135388 (HLA-DRB1*1501, p?0.01), rs7090530 (IL2RA, p?0.026) and rs1841770 (ZIC1, p?0.017) with a younger age at MS onset and of rs12044852 (CD58, p?0.035) with shorter time to reach EDSS6. 相似文献
993.
Ehsan Homaei Xiao-Zhuang Jin Edmond Ho Nang Pow Jukka Pekka Matinlinna James Kit-Hon Tsoi Khalil Farhangdoost 《Dental materials》2018,34(7):e149-e157
Objectives
The purpose of this study was to estimate the fatigue life of premolars restored with two dental ceramics, lithium disilicate (LD) and polymer infiltrated ceramic (PIC) using the numerical method and compare it with the published in vitro data.Methods
A premolar restored with full-coverage crown was digitized. The volumetric shape of tooth tissues and crowns were created in Mimics®. They were transferred to IA-FEMesh for mesh generation and the model was analyzed with Abaqus. By combining the stress distribution results with fatigue stress–life (S–N) approach, the lifetime of restored premolars was predicted.Results
The predicted lifetime was 1,231,318 cycles for LD with fatigue load of 1400 N, while the one for PIC was 475,063 cycles with the load of 870 N. The peak value of maximum principal stress occurred at the contact area (LD: 172 MPa and PIC: 96 MPa) and central fossa (LD: 100 MPa and PIC: 64 MPa) for both ceramics which were the most seen failure areas in the experiment. In the adhesive layer, the maximum shear stress was observed at the shoulder area (LD: 53.6 MPa and PIC: 29 MPa).Significance
The fatigue life and failure modes of all-ceramic crown determined by the numerical method seem to correlate well with the previous experimental study. 相似文献994.
Mohamed M. El-Sayed Seleman Sabbah Ataya Mohamed M. Z. Ahmed Ahmed M. M. Hassan Fahamsyah H. Latief Khalil Hajlaoui Ahmed E. El-Nikhaily Mohamed I. A. Habba 《Materials》2022,15(8)
The current work investigates the viability of utilizing a friction stir deposition (FSD) technique to fabricate continuous multilayer high-performance, metal-based nanoceramic composites. For this purpose, AA2011/nano Al2O3 composites were successfully produced using AA2011 as a matrix in two temper conditions (i.e., AA2011-T6 and AA2011-O). The deposition of matrices without nano Al2O3 addition was also friction stir deposited for comparison purposes. The deposition process parameters were an 800 rpm rod rotation speed and a 5 mm/min feed rate. Relative density and mechanical properties (i.e., hardness, compressive strength, and wear resistance) were evaluated on the base materials, deposited matrices, and produced composites. The microstructural features of the base materials and the friction stir deposited materials were investigated using an optical microscope (OM) and a scanning electron microscope (SEM) equipped with an EDS analysis system. The worn surface was also examined using SEM. The suggested technique with the applied parameters succeeded in producing defect-free deposited continuous multilayer AA2011-T6/nano Al2O3 and AA2011-O/nano Al2O3 composites, revealing well-bonded layers, grain refined microstructures, and homogeneously distributed Al2O3 particles. The deposited composites showed higher hardness, compressive strengths, and wear resistance than the deposited AA2011 matrices at the two temper conditions. Using the AA2011-T6 temper condition as a matrix, the produced composite showed the highest wear resistance among all the deposited and base materials. 相似文献
995.
Abd-El-Maeboud KH Ghazy AA Nadeem AA Al-Sharaky A Khalil AE 《The journal of obstetrics and gynaecology research》2008,34(1):78-84
AIM: To evaluate the effect of vaginal pH on the efficacy of misoprostol for induction of midtrimester abortion. METHODS: The study comprised 110 women, with a gestational age of 14-26 weeks, with a missed abortion as an indication for the induction of abortion. On admission, the vaginal pH was measured and two groups were generated: (A) those with pH<5 (n=63); and (B) those with pH >or= 5 (n=47). All of the women received intravaginal misoprostol tablets moistened with 3 mL of 5% acetic acid, 200 microg every 4 h for a maximum of 5 doses within 24 h. If the patient did not have adequate uterine contractions, the same regimen was repeated over the following 24 h and if no response was achieved, this was considered a failure of therapy. RESULTS: All patients aborted within 48 h. A significant positive correlation between vaginal pH and the misoprostol application-abortion interval was found. The mean induction-abortion interval was significantly shorter in group A compared to group B (12.1 vs 23.6 h, P<0.001), with abortion rates at 24 h being 100% and 63.8%, respectively. Moreover, a significantly lower dose of misoprostol was used in group A with a lower incidence of fever and abdominal pain. CONCLUSION: Vaginal pH influences the efficacy of misoprostol administered vaginally for the induction of midtrimester abortion. The presence of this relationship, despite premoistening misoprostol with an acidifying agent, suggests that the effect of vaginal pH might extend beyond affecting the pharmacokinetics of the drug. 相似文献
996.
Sayed KA Khalil AA Yousaf M Labadie G Kumar GM Franzblau SG Mayer AM Avery MA Hamann MT 《Journal of natural products》2008,71(3):300-308
Chemical transformation studies were conducted on (-)-8-hydroxymanzamine A ( 1), (-)-manzamine F ( 2), manzamine A ( 3), and (+)-8-hydroxymanzamine A ( 4), isolated from Indo-Pacific Acanthostrongylophora sponges. Thirteen new semisynthetic manzamine derivatives, including four Delta (34,35) manzamines ( 5, 6, 8, and 9) and the unprecedented manzamine derivative 17, are reported. The potent in vitro activities of the obtained semisynthetic manzamines against activated brain microglia and the AIDS opportunistic infection pathogen Mycobacterium tuberculosis are presented. 相似文献
997.
Investigation of an EtOAc-soluble extract of the soft coral Sarcophyton stolidotum resulted in the isolation of seven new 14-membered carbocyclic cembranes, sarcostolides A-G (1-7), together with two known cembrane diterpenes, isosarcophytoxide and isosarcophine. The structural elucidation of these metabolites was determined on the basis of spectroscopic analyses, particularly 2D NMR techniques. Sarcostolide E (5) exhibited weak to moderate cytotoxic activity against human WiDr and Daoy tumor cell lines. A biogenetic pathway and relationship for compounds 1-7 was also proposed. 相似文献
998.
Paraoxonase (PON1) is principally complexed to HDL and is responsible, at least in part, for its antioxidant properties. PON1 activity decreases in several pathologies associated with atherosclerosis. The aim of this study was to investigate the PON1 activity and factors influencing its activity as a function of age. One hundred and twenty nine healthy subjects aged between 22 and 89 years were recruited for the study. We found that serum PON1 activity significantly decreased with age (r=-0.38, p<0.0001) while its arylesterase activity as well as its concentration in the serum did not change significantly. HDL concentrations remained unchanged with age, however, Apo A1 concentration showed a slight negative but significant correlation with age (r=-0.19, p<0.027). Moreover, the total cholesterol concentration was positively and significantly correlated with age (r=0.40, p<0.001). Thus, our results suggest that the decrease in PON1 activity cannot be explained by the decrease in Apo A1 concentrations with age. HDL from elderly subjects was more susceptible to oxidation than HDL from young subjects measured by higher lipid peroxidation rate. Thus, the decrease in PON1 activity may contribute to this increased susceptibility of HDL to oxidation with aging. Altogether our results suggest that the decrease in PON1 activity may be related to the development of oxidative stress conditions with aging and the increased HDL susceptibility to oxidation in elderly subjects. 相似文献
999.
Raheel Asghar Muhammad Faisal Javed Raid Alrowais Alamgir Khalil Abdeliazim Mustafa Mohamed Abdullah Mohamed Nikolai Ivanovich Vatin 《Materials》2022,15(7)
This research presents a novel approach of artificial intelligence (AI) based gene expression programming (GEP) for predicting the lateral load carrying capacity of RC rectangular columns when subjected to earthquake loading. To achieve the desired research objective, an experimental database assembled by the Pacific Earthquake Engineering Research (PEER) center consisting of 250 cyclic tested samples of RC rectangular columns was employed. Seven input variables of these column samples were utilized to develop the coveted analytical models against the established capacity outputs. The selection of these input variables was based on the linear regression and cosine amplitude method. Based on the GEP modelling results, two analytical models were proposed for computing the flexural and shear capacity of RC rectangular columns. The performance of both these models was evaluated based on the four key fitness indicators, i.e., coefficient of determination (R2), root mean squared error (RMSE), mean absolute error (MAE), and root relative squared error (RRSE). From the performance evaluation results of these models, R2, RMSE, MAE, and RRSE were found to be 0.96, 53.41, 38.12, and 0.20, respectively, for the flexural capacity model, and 0.95, 39.47, 28.77, and 0.22, respectively, for the shear capacity model. In addition to these fitness criteria, the performance of the proposed models was also assessed by making a comparison with the American design code of concrete structures ACI 318-19. The ACI model reported R2, RMSE, MAE, and RRSE to be 0.88, 101.86, 51.74, and 0.39, respectively, for flexural capacity, and 0.87, 238.74, 183.66, and 1.35, respectively, for shear capacity outputs. The comparison depicted a better performance and higher accuracy of the proposed models as compared to that of ACI 318-19. 相似文献
1000.