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<正>Glyphosateisabroad-spectrumherbicideoriginallyintroducedto themarketin1974bytheagrochemicalcompanyMonsanto.More than 40 years down the line, glyphosate has become one of the most economically meaningful herbicides, with a global use of more than1.8 million pounds in 2014 (Benbrook, 2016). In non resistant plants,  相似文献   
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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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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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