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71.
Stored red blood cells undergo progressive structural and functional changes over time. Recently, concerns have been raised about the transfusion of older red blood cell (RBC) concentrates after cardiac surgery. The objective of the study was to test the hypothesis that longer storage time of RBCs increases the risk of adverse outcome after cardiac surgery. This is a retrospective cohort study which includes patients who underwent coronary artery bypass surgery and/or valve surgery. All patients were operated in the period from September 2006 to December 2010 and received 1 to 6 units of RBCs intraoperative or after surgery. Patients were divided into two groups according to the storage time of the RBCs. The “younger” group comprised patients who received RBCs ≤14 days old (n?=?111) and the “any older” group comprised patients who received RBCs >14 days old (n?=?710). Using univariable and multivariable regression analysis, we examined the effect of storage time on the primary composite endpoint of death, myocardial infarction, and stroke (major adverse cardiovascular events). Secondary outcomes were prolonged ICU and hospital stay. Data of 821 patients who received a total of 2,004 RBCs were analyzed. The median storage time for the younger group was 13?±?2 days, the median storage time for the “any older” group was 21?±?5 days. The incidence of the primary outcome was 8.6 % in the “any older” group and 4.5 % in the younger group (adjusted odds ratio (OR) 1.68; 95 % confidence interval (CI), 0.65–4.34). Prolonged ICU stay was 12.3 % in the “any older” group and 6.3 % in the younger group (adjusted OR 1.58; 95 % CI, 0.69–3.66). In patients undergoing cardiac surgery, transfusion of RBCs stored for more than 2 weeks was not associated with adverse outcomes.  相似文献   
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To determine the effect of group composition on backtest (Bt) responses and to determine the predictive value of the Bt for the physiological stress response to weaning and mixing, 814 pigs were backtested at 3, 10 and 17 days of age. Twenty-nine percent of all pigs were cross-fostered at 3 days according to Bt responses and groups were formed of animals with high responses (HR) only, low responses (LR) only or mixed groups of animals with high, intermediate and low responses (MISC). Original litters (OR, no cross-fostering) were used as controls. Cortisol responses were measured in saliva after weaning at 4 weeks of age and after moving and mixing at 9 weeks of age.In HR groups, mean Bt responses decreased after cross-fostering while in LR groups, mean Bt scores increased. In both groups, Bt responses of individual animals before and after cross-fostering were not correlated. In MISC and OR groups, all Bt scores were correlated. Weaning and mixing caused a significant rise in cortisol in all animals while moving or weighing did not. No relations were found between Bt scores and cortisol levels.We conclude that Bt behaviour can change according to the social environment between 3 and 10 days. This could be intentional, to form a varied group, or it might be caused by a change in the hypothalamic-pituitary-adrenal (HPA) function due to social stress. At an older age, this ability is lost and common farm practises such as regrouping, weaning and mixing of piglets at ages >10 days might have a negative effect on the piglets.  相似文献   
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OBJECTIVE: To assess the relationship between plasma nevirapine concentrations and plasma HIV-1 RNA response in HIV-1-infected patients.Design: An observational cohort analysis. METHODS: Plasma samples were obtained on a routine basis from 189 patients receiving nevirapine 200mg twice daily, and plasma nevirapine concentrations were measured with reversed phase high performance liquid chromatography. Patients were divided into two groups based on plasma nevirapine concentrations below (and equal to) or above 3 mg/L. The association between steady-state nevirapine concentrations and plasma HIV-1 RNA was determined by multivariate analysis. RESULTS: Out of 189 patients, 13 (7%) had low nevirapine plasma concentrations and 176 patients had concentrations above 3 mg/L. In total, 22 (12%) patients showed virological failure and 8 patients (4%) discontinued nevirapine because of adverse effects. The risk of failure in patients with nevirapine plasma concentrations 相似文献   
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Symptomatic nephrotoxicity is a well-known complication of indinavir treatment. However, little is known about the relevance of other abnormalities, such as leukocyturia during use of indinavir. We determined the prevalence, risk factors, and consequences of persistent leukocyturia in a prospectively monitored cohort of indinavir users in three adult outpatient clinics. Patients were monitored for nephrotoxicity at regular visits (every 3 months) between August 1998 and September 2000. Monitoring involved urine dipstick analysis and microscopy for pH, erythrocytes, leukocytes, and indinavir crystals. The urine albumin concentration/creatinine concentration ratio and serum creatinine and indinavir plasma concentrations were measured, and urinary tract infection was excluded. Urologic symptoms were retrieved from medical records. Of 184 patients with at least one assessment, 35% had leukocyturia (i.e., >75 cells/microL) at least once during the study period, which coincided with mild increase in the serum albumin level, erythrocyturia, and crystalluria. Thirty-two (24%) of 134 patients with two or more assessments had persistent leukocyturia (i.e., on two or more occasions). Risk factors were indinavir plasma concentration of >9 mg/L, urine pH of >5.7, and crystalluria. Persistent leukocyturia was associated with a gradual loss of renal function but not with urologic symptoms. The data show that leukocyturia is a frequent finding and emphasize the need for monitoring renal function during indinavir treatment, even in the absence of urologic symptoms.  相似文献   
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Objective. To assess whether circulating concentrations of soluble tumor necrosis factor receptors (sTNFR; p55 and p75), soluble interleukin-2 receptors (sIL-2R), tumor necrosis factor α (TNFα), and interleukin-6 (IL-6) reflect clinical response and whether changes are dependent on the drug used in rheumatoid arthritis (RA) patients taking methotrexate (MTX) or azathioprine (AZA). Methods. These cytokines and soluble receptors were assessed in 20 control subjects and serially for up to 48 weeks in 61 RA patients, by bioassay (IL-6) and immunoassays (sTNFR, sIL-2R, TNFα, and IL-6). Results. Concentrations of p55 and p75, sIL-2R, and TNFα (but not IL-6) were significantly higher in RA patients than in controls. Significant decreases in sIL-2R and p55 concentrations were associated with clinical improvement and were observed in patients treated with MTX, but not AZA. Both treatments induced decreases in IL-6 concentrations, but circulating AZA (or its metabolites) appears to interfere with the measurement of IL-6 bioactivity. TNFα and p75 levels did not show significant changes. Conclusion. Measurement of circulating sIL-2R, p55, and IL-6 may be useful in the evaluation of RA disease activity and response to therapy. Interference by circulating levels of drugs must be ruled out when bioassays are used to evaluate cytokine levels.  相似文献   
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Background  

Staff shortages could harm the provision and quality of health care in Uganda, so staff retention and motivation are crucial. Understanding the impact of HIV/AIDS on staff contributes to designing appropriate retention and motivation strategies. This research aimed 'to identify the influence of HIV/AIDS on staff working in general hospitals at district level in rural areas and to explore support required and offered to deal with HIV/AIDS in the workplace'. Its results were to inform strategies to mitigate the impact of HIV/AIDS on hospital staff.  相似文献   
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