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排序方式: 共有2875条查询结果,搜索用时 15 毫秒
61.
Thye Foo Choo Mohamad Amran Mohd Salleh Kuan Ying Kok Khamirul Amin Matori Suraya Abdul Rashid 《Materials》2020,13(22)
Grog is an additive material that plays important roles in ceramic making. It improves the fabrication process of green bodies as well as the physical properties of fired bodies. Few low-cost materials and wastes have found their application as grog in recent years, thus encouraging the replacement of commercial grogs with cost-saving materials. Coal fly ash, a combustion waste produced by coal-fired power plant, has the potential to be converted into grog owing to its small particle sizes and high content of silica and alumina. In this study, grog was derived from coal fly ash and mixed with kaolin clay to produce ceramics. Effects of the grog addition on the resultant ceramics were investigated. It was found that, to a certain extent, the grog addition reduced the firing shrinkage and increased the total porosity of the ceramics. The dimensional stability of the ceramics at a firing temperature of 1200 °C was also not noticeably affected by the grog. However, the grog addition in general had negative effects on the biaxial flexural strength and refractoriness of the ceramics. 相似文献
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Mejbah Uddin Bhuiyan Stephen P. Luby Rashid Uz Zaman M. Waliur Rahman M. A. Yushuf Sharker M. Jahangir Hossain Choudhury H. Rasul A. R. M. Saifuddin Ekram Mahmudur Rahman Katharine Sturm-Ramirez Eduardo Azziz-Baumgartner Emily S. Gurley 《The American journal of tropical medicine and hygiene》2014,91(1):165-172
During April 2007–April 2010, surveillance physicians in adult and pediatric medicine wards of three tertiary public hospitals in Bangladesh identified patients who developed hospital-acquired diarrhea. We calculated incidence of hospital-acquired diarrhea. To identify risk factors, we compared these patients to randomly selected patients from the same wards who were admitted > 72 hours without having diarrhea. The incidence of hospital-acquired diarrhea was 4.8 cases per 1,000 patient-days. Children < 1 year of age were more likely to develop hospital-acquired diarrhea than older children. The risk of developing hospital-acquired diarrhea increased for each additional day of hospitalization beyond 72 hours, whereas exposure to antibiotics within 72 hours of admission decreased the risk. There were three deaths among case-patients; all were infants. Patients, particularly young children, are at risk for hospital-acquired diarrhea and associated deaths in Bangladeshi hospitals. Further research to identify the responsible organisms and transmission routes could inform prevention strategies. 相似文献
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Joseph M. Castellano Rashid Deane Andrew J. Gottesdiener Philip B. Verghese Floy R. Stewart Tim West Andrew C. Paoletti Tristan R. Kasper Ronald B. DeMattos Berislav V. Zlokovic David M. Holtzman 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(38):15502-15507
The apolipoprotein E (APOE)-ε4 allele is the strongest genetic risk factor for late-onset, sporadic Alzheimer''s disease, likely increasing risk by altering amyloid-β (Aβ) accumulation. We recently demonstrated that the low-density lipoprotein receptor (LDLR) is a major apoE receptor in the brain that strongly regulates amyloid plaque deposition. In the current study, we sought to understand the mechanism by which LDLR regulates Aβ accumulation by altering Aβ clearance from brain interstitial fluid. We hypothesized that increasing LDLR levels enhances blood–brain barrier-mediated Aβ clearance, thus leading to reduced Aβ accumulation. Using the brain Aβ efflux index method, we found that blood–brain barrier-mediated clearance of exogenously administered Aβ is enhanced with LDLR overexpression. We next developed a method to directly assess the elimination of centrally derived, endogenous Aβ into the plasma of mice using an anti-Aβ antibody that prevents degradation of plasma Aβ, allowing its rate of appearance from the brain to be measured. Using this plasma Aβ accumulation technique, we found that LDLR overexpression enhances brain-to-blood Aβ transport. Together, our results suggest a unique mechanism by which LDLR regulates brain-to-blood Aβ clearance, which may serve as a useful therapeutic avenue in targeting Aβ clearance from the brain. 相似文献
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Brian P. Yochim Kaycee Rashid Neda C. Raymond Sherry A. Beaudreau 《The Clinical neuropsychologist》2013,27(6):973-987
Naming, or word-finding ability, is typically assessed using measures that require a patient to name a pictured object. Words used less frequently tend to be more difficult to find when speaking; thus word frequency can be used as a measure of item difficulty on such tests. However, frequency data for words on naming measures has either not been used in the creation of these tests or has been derived from data on how frequently words have been used in written materials. The present study determined how frequently words on the Boston Naming Test (BNT), the Neuropsychological Assessment Battery (NAB) naming subtest, the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) naming subtest, and auditory naming measures developed by Hamberger and Seidel (2003, Journal of the International Neuropsychological Society, 9, 479) and Brandt et al. (2010, The Clinical Neuropsychologist, 24, 1326) are used in spoken language. Items on the auditory naming measures had the highest mean frequency, and the BNT items 30–60 had the lowest mean frequency. Furthermore, item frequency on the full BNT, NAB naming forms 1 and 2, and RBANS forms A correlated with item number, indicating items increase in difficulty on these tests, with trends in the same direction found for RBANS form B and Hamberger and Seidel’s auditory naming measure. Finally, differences in mean word frequency between tests underscore how interpretation of change in naming ability based on different measures should be made with caution. 相似文献
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Abdullah MH Othman Z Noor HM Arshad SS Yusof AK Jamal R Rahman AR 《Journal of cardiology》2012,60(3):192-203
The molecular basis of coronary artery disease (CAD) has been widely studied in the western world but there is no published work on the Malaysian population. This study looked at the global gene expression profiling of the peripheral blood of patients with CAD from the 3 main ethnic groups in Malaysia. Male subjects selected were based on angiographically confirmed CAD (≥50% stenosis) and normal control subjects (0% stenosis) with age range of 55.6±5.3 and 51.0±5.5years, respectively. The global gene expression of 12 angiographically documented CAD patients and 11 matched control subjects were performed. The combined group samples identified 6 up regulated differential expression (DE) genes (GHRL, LTA, CBS, HP, ITGA2B, and OLR1) and 12 down regulated DE genes (IL18R1, ITGA2B, IL18RAP, HP, OLR1, SOD2 ITGB3, IL1B, MMP9, PLA2G7, UTS2, and CBS) to be involved in CAD at the fold change of 1.3 with fault discovery rate (FDR) of 1%. Three genes, MMP9, IL1B, and SOD2 were down regulated in all the 3 ethnic groups making them potential biomarker candidates for CAD across all three ethnicities. Further verification in a cohort study is needed. 相似文献