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141.
The concentration of six HMs (Cd, Cr, Co, Pb, Hg and Ni) was analysed in 321 organically grown winter and spring wheat genotypes from six genotype groups, i.e. selections, old landraces, primitive wheat, spelt, old cultivars and cultivars. Also the potential risk of individual toxic HM to human health was estimated by using the Hazard Quotient (HQ). Significantly the lowest grain concentration of Cd was found in primitive wheat as compared to all other investigated genotype groups. Intake of HM by consumption of whole wheat grain was not found to pose a health risk to human for any of the investigated genotype groups. The bio-concentration factor of Cd for the different genotype groups indicated a lower ability to accumulate Cd for primitive wheat as compared to other genotype groups. The primitive wheat was found the most promising and might be of interest in future wheat breeding programs to develop wheat genotypes with low HMs concentration in the grain.  相似文献   
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The heavy metals (Fe, Zn, Pb, Ni, Cr, Co, and Cd) burden in wastewater, soil, and vegetable samples from a wastewater irrigated farm located at KorleBu, Accra has been investigated. Flame atomic absorption spectrometry after microwave digestion using a combination of HNO3, HCl, and H2O2 (for water), and HNO3 and HCl (for soil and vegetables). The mean concentrations (in milligrams per kilogram) of heavy metals in the soil samples were in the order of Fe (171?±?5.22)?>?Zn (36.06?±?4.54)?>?Pb (33.35?±?35.62)?>?Ni (6.31?±?8.15)?>?Cr (3.40?±?3.63)?>?Co (1.36?±?0.31)?>?Cd (0.43?±?0.24), while the vegetables were in the order of Fe (183.11?±?161.2)?>?Zn (5.38?±?3.50)?>?Ni (3.52?±?1.27)?>?Pb (2.49?±?1.81)?>?Cr (1.46?±?0.51)?>?Co (0.66?±?0.25)?>?Cd (0.36?±?0.15). The bioconcentration factors suggest environmental monitoring for the heavy metals as follows: Cd (0.828), Cr (0.431), Ni (0.558), Co (0.485), and Fe (1.067). Estimated daily intakes were very low for both children and adults except Fe (0.767 mg/kg/day) in children. The population that consume vegetables from the study area were, however, estimated to be safe based on the results obtained from the health risk index, which were all?<?<1. The sodium absorption ratio according to FAO (1985) classifications indicate that the wastewater in the study area is unsuitable for irrigation purposes.  相似文献   
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Several factors associated with poor outcome in patients with prenatally diagnosed sacrococcygeal teratoma (SCT) have been found. However, the prognostic accuracy of these factors has not been well established. Therefore, we aimed to systematically review the prognostic accuracy of factors associated with poor outcome in these patients. We queried Search Premier, COCHRANE Library, EMCARE, EMBASE, PubMed, ScienceDirect, and Web of Science databases to identify studies regarding patients with prenatally diagnosed SCT. Poor outcome was defined as termination of pregnancy (TOP), intrauterine fetal death (IUFD), or perinatal death. We estimated the odds ratio of factors associated with poor outcome. Eleven studies (447 patients) were included. Overall mortality, including TOP, was 34.9%. Factors associated with poor outcome in fetuses with prenatally diagnosed SCT were cardiomegaly, hypervascular tumor, solid tumor morphology, fetal hydrops, and placentomegaly. A tumor volume to fetal weight ratio (TFR) of >0.12 before a gestational age of 24 weeks is predictive of poor outcome. The prognostic accuracy of factors associated with poor outcome in fetuses prenatally diagnosed with SCT seems promising. Factors associated with cardiac failure such as cardiomegaly, hypervascular tumor, solid tumor morphology, fetal hydrops, placentomegaly, and TFR >0.12 were found to be predictive of poor outcome.  相似文献   
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Recent research on the effects of personal threat suggests that perceived threat might enhance pro-environmental behavior when pro-environmental norms are in focus. In three experiments we found support for the latter assumption, showing that mortality salience and salience of pro-environmental norms interacted in predicting pro-environmental attitudes and information search (Study 1), sustainable behavior in a forest management game (Study 2), as well as pro-environmental intentions and behavior (Study 3). Specifically, mortality salience increased pro-environmental conduct only when pro-environmental norms were salient. Moreover, norm salience only had an effect on pro-environmental attitudes and behavior when the threat of personal mortality was salient. We discuss the implications of these results for both terror management theory and the promotion of pro-environmental behaviors.  相似文献   
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