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31.
Mojdeh Ghabaee Ali Zandieh Shahrzad Mohebbi Mohammad Fakhri Homa Sadeghian Fatemeh Divani Hamed Amirifard Mohammadreza Mousavi-Mirkala Majid Ghaffarpour 《Acta neurologica Belgica》2014,114(1):41-45
We aimed to compare the association of high-sensitivity C-reactive protein (CRP) and National Institutes of Health Stroke Scale (NIHSS) score with mortality risk and to determine the optimal threshold of CRP for prediction of mortality in ischemic-stroke patients. A series of 162 patients with first-ever ischemic-stroke admitted within 24 h after onset of symptoms was enrolled. CRP and NIHSS score were estimated on admission and their predictive abilities for mortality at 7 days were determined by logistic-regression analyses. Receiver-Operating Characteristic (ROC) curves were depicted to identify the optimal cut-off of CRP, using the maximum Youden-index and the shortest-distance methods. Deceased patients had higher levels of CRP and NIHSS on admission (8.87 ± 7.11 vs. 2.20 ± 4.71 mg/l for CRP, and 17.31 ± 6.36 vs. 8.70 ± 4.85 U for NIHSS, respectively, P < 0.01). CRP and NIHSS were correlated with each other (r 2 = 0.39, P < 0.001) and were also independently associated with increased risk of mortality [odds ratios (95 % confidence interval) of 1.16 (1.05–1.28) and 1.20 (1.07–1.35) for CRP and NIHSS, respectively, P < 0.01]. The areas under the ROC curves of CRP and NIHSS for mortality were 0.82 and 0.84, respectively. The CRP value of 2.2 mg/l was identified as the optimal cut-off value for prediction of mortality within 7 days (sensitivity: 0.81, specificity: 0.80). Thus, CRP as an independent predictor of mortality following ischemic-stroke is comparable with NIHSS and the value of 2.2 mg/l yields the optimum sensitivity and specificity for mortality prediction. 相似文献
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Behnam Bolhari Mohammad Hossein Nekoofar Mohammadreza Sharifian Sholeh Ghabrai Naghmeh Meraji Paul M.H. Dummer 《Journal of endodontics》2014
Introduction
The aim of this study was to compare the surface microhardness of BioAggregate, ProRoot MTA, and CEM Cement when exposed to an acidic environment or phosphate-buffered saline (PBS) as a synthetic tissue fluid.Methods
Ninety cylindrical molds made of polymethyl methacrylate with an internal diameter of 6 mm and height of 4 mm (according to ASTM E384 standard for microhardness tests) were fabricated and filled with BioAggregate (n = 30), tooth-colored ProRoot MTA (n = 30), or CEM Cement (n = 30). Each group was then divided into 3 subgroups of 10 specimens consisting of those exposed to distilled water, exposed to PBS (pH = 7.4), or exposed to butyric acid (pH = 5.4). After 1 week the Vickers surface microhardness test was performed. Statistical analysis included 2-way analysis of variance, followed by post hoc Dunnett T3 in cases with lack of homoscedasticity and Tukey honestly significant difference in cases with homoscedasticity.Results
The indentations obtained from the CEM Cement specimens exposed to an acidic pH were not readable because of incomplete setting. There was a significant difference between the microhardness of the materials regardless of the environmental conditions (P < .001). In all the environmental conditions, MTA had significantly higher and CEM Cement had significantly lower microhardness values (P < .001). All experimental cements had significantly higher microhardness values when exposed to PBS (P < .001) and had significantly lower microhardness values when exposed to butyric acid (P < .001).Conclusions
The surface microhardness of BioAggregate, ProRoot MTA, and CEM Cement was reduced significantly by exposure to butyric acid and increased significantly by exposure to PBS. In all environmental conditions, MTA had significantly higher microhardness values. 相似文献35.
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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
38.
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
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Mohammadreza Seyyedmajidi Kianoosh Falaknazi Dariush Mirsattari Homayoun Zojaji Mohammad Roshani Farhad Lahmi Peyman Gooran Orimi Maryam Hadizadeh Mohammadreza Zali 《Arab Journal Of Gastroenterology》2011,12(3):150-153
Background and study aimsUraemic patients show susceptibility to gastrointestinal mucosal lesions and colonisation by Helicobacter pylori (HP). Antibiotic resistance constitutes a problem in treatment and bismuth preparations are toxic in uraemic patients. This study aimed to assess the correlation between creatinine clearance (CrCl) and eradication of HP infection with new sequential and standard triple therapeutic regimens.Patients and methodsA total of 120 HP-positive patients with renal function impairment and 60 control patients with HP infection were enrolled in this study. Patients were divided into four groups on the basis of CrCl and were randomly assigned to one of the two different regimens: A 14-day standard triple therapy with 20 mg omeprazole bid, 1000 mg amoxicillin bid and 500 mg clarithromycin bid and a new sequential regimen with 20 mg omeprazole bid and 1000 mg amoxicillin bid both for 14 days, 500 mg ciprofloxacin bid for the first 7 days and 200 mg furazolidone bid for the last 7 days. Doses of amoxicillin, clarithromycin and ciprofloxacin were reduced to 50% in the cases of CrCl <30 mg dl?1.ResultsOne hundred and sixty two out of 180 HP-positive patients (54.3% male, 51.6 ± 12.1 years) completed treatment in the four groups and were studied. According to renal function they were classified into group A (n = 39), haemodialysis (HD) patients; group B (n = 37), CrCl <30 mg dl?1 without HD; group C (n = 36), CrCl between 30 and 60 mg dl?1; and group D (n = 50), control subjects with CrCl >90 mg dl?1. HP was successfully eradicated in 77.7% of patients with standard triple therapy and in 81.4% of patients with the sequential therapy. There was no significant difference among the study groups in the rate of HP-infection eradication with both regimens.ConclusionHP eradication rates did not differ with both sequential and standard therapeutic regimens in uraemic and non-uraemic patients. We, therefore, prefer the standard triple therapy due to its simplicity and reported. 相似文献
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