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71.
Alcohol abuse and chronic hepatitis C virus(HCV)infection are two major causes of chronic liver disease in the United States.About 10%-15%of liver transplants performed in the United States are for patients with cirrhosis due to combined alcohol and HCV infection.Data on outcomes on graft and patient survival,HCV recurrence,and relapse of alcohol use comparing transplants in hepatitis C positive drinkers compared to alcohol abuse or hepatitis C alone are conflicting in the literature.Some studies report a slightly better overall outcome in patients who were transplanted for alcoholic cirrhosis vs those transplanted for HCV alone or for combined HCV and alcohol related cirrhosis.However,some other studies do not support these observations.However,most studies are limited to a retrospective design or small sample size.Larger prospective multicenter studies are needed to better define the outcomes in hepatitis C drinkers.  相似文献   
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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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CD13/Aminopeptidase N is a transmembrane metalloproteinase that is expressed in many tissues where it regulates various cellular functions. In inflammation, CD13 is expressed on myeloid cells, is up‐regulated on endothelial cells at sites of inflammation and mediates monocyte/endothelial adhesion by homotypic interactions. In animal models the lack of CD13 alters the profiles of infiltrating inflammatory cells at sites of ischaemic injury. Here, we found that CD13 expression is enriched specifically on the pro‐inflammatory subset of monocytes, suggesting that CD13 may regulate trafficking and function of specific subsets of immune cells. To further dissect the mechanisms regulating CD13‐dependent trafficking we used the murine model of thioglycollate‐induced sterile peritonitis. Peritoneal monocytes, macrophages and dendritic cells were significantly decreased in inflammatory exudates from global CD13KO animals when compared with wild‐type controls. Furthermore, adoptive transfer of wild‐type and CD13KO primary myeloid cells, or wild‐type myeloid cells pre‐treated with CD13‐blocking antibodies into thioglycollate‐challenged wild‐type recipients demonstrated fewer CD13KO or treated cells in the lavage, suggesting that CD13 expression confers a competitive advantage in trafficking. Similarly, both wild‐type and CD13KO cells were reduced in infiltrates in CD13KO recipients, confirming that both monocytic and endothelial CD13 contribute to trafficking. Finally, murine monocyte cell lines expressing mouse/human chimeric CD13 molecules demonstrated that the C‐terminal domain of the protein mediates CD13 adhesion. Therefore, this work verifies that the altered inflammatory trafficking in CD13KO mice is the result of aberrant myeloid cell subset trafficking and further defines the molecular mechanisms underlying this regulation.  相似文献   
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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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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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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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