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European Journal of Plant Pathology - In this study, propolis extract (EPE) and oregano essential oil (OEO), both natural products with different bioactive compounds, were evaluated in vitro and in...  相似文献   
133.
Greenery is assumed to promote physical activity at school grounds by facilitating open and flexible play situations that engage many children. The role of greenery for school ground activity was investigated at two schools, one of which contained a substantial amount of greenery and the other one little greenery. All in all 197 children from 4th (10–11 years) and 6th grade (12–13 years), were involved in a one week field study, documenting self-reported school ground use, their favourite places and favourite activities and counting their steps by pedometer. The most common school ground activities were related to the use of balls as part of different sports, games and other playful activity. The more extensive green areas belonged to children's favourite places, but were little used, whereas settings with a mix of green and built elements in proximity to buildings were well-used favourites. Physical activity in steps was similar at the two schools, but on average girls got less of the activity they need during recess. Greenery was found important by contributing to settings attractive to visit for girls as well as boys and for younger as well as older children, if located in ways that also supported peer interaction and various games.  相似文献   
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The objective of the present study was to evaluate the concentration- and time-dependent effects of the organophosphorus insecticides malathion and azinphos-methyl on polyamine metabolism, and relate them to normal and altered embryonic development of the common toad Rhinella arenarum. Control embryos showed that the higher polyamines spermidine and spermine acquired importance with respect to the diamine putrescine as embryonic development progressed. The activity of ornithine decarboxylase significantly decreased in complete operculum embryos. Continuous exposure to malathion caused a decrease in polyamine levels during embryonic development. However, there was an increase in putrescine levels in complete operculum embryos exposed to a sublethal concentration of the insecticide. Embryos exposed to malathion displayed a decrease in fresh weight and size, along with an increase in the number of malformed individuals. R. arenarum embryos exposed to a lethal concentration of azinphos-methyl showed an increase in putrescine levels and a decrease in spermidine and spermine levels, accompanied by an increase in ornithine decarboxylase activity. In conclusion, as the embryonic development of the toad R. arenarum progresses, polyamine metabolism shifts to higher polyamine levels with a more preponderant contribution of spermidine and spermine with respect to putrescine and involves a dramatic change in ornithine decarboxylase activity, one of the key regulatory enzymes of the pathway. Organophosphorus insecticides are capable of altering polyamine metabolism, slowing embryo development in parallel with a reduction in spermidine and spermine levels. An increase in the oxidative degradation of polyamines might be involved in the toxic action of organophosphorus insecticides and might also be related to other effects such as teratogenesis.  相似文献   
136.
The molecular mechanisms involved in the development of type 2 diabetes are poorly understood. Starting from genome-wide genotype data for 1924 diabetic cases and 2938 population controls generated by the Wellcome Trust Case Control Consortium, we set out to detect replicated diabetes association signals through analysis of 3757 additional cases and 5346 controls and by integration of our findings with equivalent data from other international consortia. We detected diabetes susceptibility loci in and around the genes CDKAL1, CDKN2A/CDKN2B, and IGF2BP2 and confirmed the recently described associations at HHEX/IDE and SLC30A8. Our findings provide insight into the genetic architecture of type 2 diabetes, emphasizing the contribution of multiple variants of modest effect. The regions identified underscore the importance of pathways influencing pancreatic beta cell development and function in the etiology of type 2 diabetes.  相似文献   
137.
Obesity is a serious international health problem that increases the risk of several common diseases. The genetic factors predisposing to obesity are poorly understood. A genome-wide search for type 2 diabetes-susceptibility genes identified a common variant in the FTO (fat mass and obesity associated) gene that predisposes to diabetes through an effect on body mass index (BMI). An additive association of the variant with BMI was replicated in 13 cohorts with 38,759 participants. The 16% of adults who are homozygous for the risk allele weighed about 3 kilograms more and had 1.67-fold increased odds of obesity when compared with those not inheriting a risk allele. This association was observed from age 7 years upward and reflects a specific increase in fat mass.  相似文献   
138.
Thysanosoma actinioides Diesing, 1834 (Cestoda: Anoplocephalidae) parasitizes domestic and wild herbivores, and its life cycle has not yet been completely elucidated. The aim of this study was to analyze the role of oribatid mites as intermediate hosts of T. actinioides. The work was carried out at a Merino sheep breeding farm situated in the Pre-Cordillera region near Bariloche City, Río Negro Province, Argentina. The proglottids of T. actinioides were obtained from feces of infected sheep. In the laboratory, they were placed in the plastic wells with oribatid mites. The species of oribatids used in this experimental trial were Zygoribatula striassima Hammer, 1962 (Family Oribatulidae) and Oribatella spp. Banks, 1895 (Family Oribatellidae). Both species became infected with larval stages of T. actinioides. However, the infective cysticercoid stage did not develop.  相似文献   
139.
Yield losses caused by a second viral infection of garlic plants previously infected with either of the isolated Allexiviruses, Garlic virus-A (GarV-A) or Garlic virus-C (GarV-C), were evaluated in a field assay carried out over four consecutive growing seasons. The treatment groups included virus-free plants (VF), plants infected only with GarV-A isolates (A), plants infected only with GarV-C isolates (C), and plants infected with a mixture of viruses that naturally infect garlic, referred to as viral-complex plants (VC). From the first crop cycle the different treatments were infected by other viruses that naturally infect garlic. At the end of the first growth cycle, significant differences in yield were observed among the four treatments. The bulb weight for VF, C, and A treatments was respectively 137%, 116%, and 96% higher than the bulb weight for the VC treatment. After the fourth growth cycle, however, non-significant differences in garlic yield between the VC, C, and A treatments were observed, whereas the yield for the VF treatment was higher than the VC treatment by 22%. Garlic yield decreased more rapidly in plants infected previously with at least one Allexivirus and then infected with other naturally occurring viruses than the plants that were virus-free at the beginning (VF plants).  相似文献   
140.
Digestibility, fecal characteristics, and levels of glucose and urea in the plasma were determined in 8 dogs that received 2 different dog foods once or 3 times daily. One dog food (A) was 5 times more expensive than the other (B). Fecal pH and consistency, digestibility of dry matter (DM), organic matter (OM), crude protein (CP), and crude fiber (CF) were determined. Blood samples were taken from 30 min before to 60 min after a meal. Digestibilities of DM, OM, and CP, and fecal consistency were higher, and daily fecal excretion and fecal pH were lower when dogs were fed food A (P < 0.001). The feeding schedule had no effect on plasma glucose and urea. Neither feeding frequency nor food × frequency interactions was significant for the parameters studied.  相似文献   
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