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Objectives. Cardiac surgery patients are excluded from SAPS2 but included in SAPS3. Neither score is evaluated for this exclusive population; however, they are used daily. We hypothesized that SAPS3 may be superior to SAPS2 in outcome prediction in cardiac surgery patients. Design. All consecutive patients undergoing cardiac surgery between January 2007 and December 2010 were included in our prospective study. Both models were tested with calibration and discrimination statistics. We compared the AUC of the ROC curves by DeLong's method and calculated OCC values. Results. A total of 5207 patients with mean age of 67.2 ± 10.9 years were admitted to the ICU. The mean length of ICU stay was 4.6 ± 7.0 days and the ICU mortality was 5.9%. The two tested models had acceptable discriminatory power (AUC: SAPS2: 0.777–0.875; SAPS3: 0.757–893). SAPS3 had a low AUC and poor calibration on admission day. SAPS2 had poor calibration on Days 1–6 and 8. Conclusions. Despite including cardiac surgery patients, SAPS3 was not superior to SAPS2 in our analysis. In this large cohort of ICU cardiac surgery patients, performance of both SAPS models was generally poor. In this subset of patients, neither scoring system is recommended.  相似文献   
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Lidocaine is commonly used for topical anesthesia of the upper airway in patient with anticipated difficult tracheal intubation undergoing awake fiberoptic intubation. Lidocaine toxicity is dose related and proportional to its plasma level. Although neurologic toxicity has been frequently observed with intravenous use, it has also been reported for topical use.  相似文献   
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Despite the demonstrated benefits of Prasugrel, a new generation thienopyridine, in the prevention of thrombotic complications after percutaneous coronary interventions (PCI) for Acute Coronary Syndromes (ACS), its use is still precluded to those many patients arriving to the cath lab pre-treated with Clopidogrel. Conclusive data on the strategy of switching from Clopidogrel to Prasugrel are still missing, therefore we aimed to perform a meta-analysis of current studies evaluating the safety and efficacy of switching from Clopidogrel to Prasugrel (PS) as compared to a standard thienopyridine therapy with Clopidogrel or Prasugrel in patients undergoing PCI. Literature archives and main scientific sessions’ abstracts were scanned for studies comparing a switching strategy from Clopidogrel to Prasugrel vs. Prasugrel or Clopidogrel. Primary efficacy endpoint was overall mortality. Secondary endpoints were: non-fatal myocardial infarction and definite/probable stent thrombosis. Safety endpoint was the rate of major bleedings according to a per-protocol definition. A total of 12 studies, involving 3956 patients, were included. Among them, 1396 patients (35.3%), received Prasugrel after a Clopidogrel treatment (PS), while 2560 (64.7%) received either Prasugrel or Clopidogrel. The switch from Clopidogrel to Prasugrel was in the majority of the studies periprocedural. The mortality was numerically lower, but not statistically significant, in the PS group as compared with patients who did not switch (1.7% vs. 3.8%, OR [95% CI]?=?0.68 [0.40,1.15], p?=?0.15, phet?=?0.61), without any relationship with patients’ risk profile (r?=??0.68 [?2.09, 0.73], p?=?0.35). Similar results were obtained for secondary efficacy endpoints and at sensitivity analysis in the majority of subgroups evaluated. Moreover, the PS strategy did not increase major bleedings as compared with standard therapy (1.4% vs. 2.5%, OR [95% CI?=?0.70 [0.39, 1.25], p?=?0.23, phet?=?0.6). The present meta-analysis confirms that, among patients undergoing PCI, switching from Clopidogrel to Prasugrel may be safely performed and therefore should be encouraged among patients eligible to Prasugrel.  相似文献   
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Although it is widely known that arsenic‐contaminated drinking water causes many diseases, arsenic's exact mode of action (MOA) is not fully understood. Induction of oxidative stress has been proposed as an important key event in the toxic MOA of arsenic. The authors' studies are centered on identifying a reactive species involved in the genotoxicity of arsenic using a catalase (CAT) knockout mouse model that is impaired in its ability to breakdown hydrogen peroxide (H2O2). The authors assessed the induction of DNA damage using the Comet assay following exposure of mouse Cat+/+ and Cat?/? primary splenic lymphocytes to monomethylarsonous acid (MMAIII) to identify the potential role of H2O2 in mediating cellular effects of this metalloid. The results showed that the Cat?/? lymphocytes are more susceptible to MMAIII than the Cat+/+ lymphocytes by a small (1.5‐fold) but statistically significant difference. CAT activity assays demonstrated that liver tissue has approximately three times more CAT activity than lymphocytes. Therefore, Comet assays were performed on primary Cat+/+, Cat+/?, and Cat?/? hepatocytes to determine if the Cat?/? cells were more susceptible to MMAIII than lymphocytes. The results showed that the Cat?/? hepatocytes exhibit higher levels of DNA strand breakage than the Cat+/+ (approximately fivefold) and Cat+/? (approximately twofold) hepatocytes exposed to MMAIII. Electron spin resonance using 5,5‐dimethyl‐1‐pyrroline‐N‐oxide as the spin‐trap agent detected the generation of ·OH via MMAIII when H2O2 was present. These experiments suggest that CAT is involved in protecting cells against the genotoxic effects of the ·OH generated by MMAIII. Environ. Mol. Mutagen. 54:317–326, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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The purpose of the current study was to investigate the role of visual information on gait control in people with Parkinson's disease as they crossed over obstacles. Twelve healthy individuals, and 12 patients with mild to moderate Parkinson's disease, walked at their preferred speeds along a walkway and stepped over obstacles of varying heights (ankle height or half-knee height), under three visual sampling conditions: dynamic (normal lighting), static (static visual samples, similar to stroboscopic lighting), and voluntary visual sampling. Subjects wore liquid crystal glasses for visual manipulation. In the static visual sampling condition only, the patients with Parkinson's disease made contact with the obstacle more often than did the control subjects. In the successful trials, the patients increased their crossing step width in the static visual sampling condition as compared to the dynamic and voluntary visual sampling conditions; the control group maintained the same step width for all visual sampling conditions. The patients showed lower horizontal mean velocity values during obstacle crossing than did the controls. The patients with Parkinson's disease were more dependent on optic flow information for successful task and postural stability than were the control subjects. Bradykinesia influenced obstacle crossing in the patients with Parkinson's disease.  相似文献   
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