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281.
The present study aimed to investigate the effect of walnut consumption on lipid profile, steroid hormones and inflammation in trained elderly men performing concurrent (resistance and endurance) training. Twenty healthy elderly males were divided into two matched groups, in a randomized controlled trial, that trained three sessions per week: concurrent training + dietary walnut consumption (15 g/day for six weeks, CTW: n = 10); concurrent training + control diet (CT: n = 10). Fasting blood samples were taken 48 hours before and after intervention for biochemical assessments. levels of high-density lipoprotein (HDL) increased only in CTW compared to baseline (19.8%, p < 0.01). Total cholesterol (TC), low-density lipoprotein (LDL) and triglyceride (TG) levels significantly decreased only for CTW (i.e., 13%, 18%, and 18.5% at p < 0.01 for all). Testosterone (T) increased after the training compared to pre-training for CTW and CT (10.3%, p < 0.01, 4.27% p < 0.05, respectively), but the increase was significantly higher in CTW (p < 0.05). Serum cortisol (C) was lower for CTW compared to CT (p < 0.01). C-reactive protein (CRP) decreased in CTW in comparison with CT. The present study revealed that 6-week moderate walnut supplementation (15 g/day) improved lipid profile, steroid hormones and systematic inflammation in aged men performing concurrent training. These findings could be attributable to the potential effect of polyunsaturated fatty acids (PUFA) contained in walnut (linoleic acid, n-6; linolenic acid, n-3).  相似文献   
282.
The ability of grape skins to catalyze in vitro conversion of p-coumaric acid to the more potent antioxidant caffeic acid was studied. Addition of different concentrations of p-coumaric to red grape skins (Cabernet Sauvignon) resulted in formation of caffeic acid. This caffeic acid formation (Y) correlated positively and linearly to p-coumaric acid consumption (X): Y = 0.5 X + 9.5; R 2 = 0.96, P < 0.0001. The kinetics of caffeic acid formation with time in response to initial p-coumaric acid levels and at different grape skin concentrations, indicated that the grape skins harboured an o-hydroxylation activity, proposedly a monophenol- or a flavonoid 3′-monooxygenase activity (EC 1.14.18.1 or EC 1.14.13.21). The K m of this crude o-hydroxylation activity in the red grape skin was 0.5 mM with p-coumaric acid.  相似文献   
283.
The regeneration potential, antioxidative enzyme activities, and genetic stability among micropropagated plantlets of Dianthus caryophyllus L. were evaluated. Multiple adventitious shoots were induced from leaf explants on Murashige and Skoog medium incorporated with various combinations and concentrations of plant growth regulators (PGRs). The highest leaf explant response (90%), number of shoots per explant (15.30?±?1.19), and shoot length (6.75?±?0.63 cm) was recorded in response to a combination of 2.5 μM 6-benzyladenine and 0.5 μM α-naphthaleneacetic acid (NAA) after 8 wks culture. Subsequent subculturing for five passages, on a medium with the same composition of PGRs, induced the highest shoot number (42.50?±?1.44), with an average shoot length of 8.06 cm after the fourth subculture. Different concentrations of indole-3-butyric acid (IBA) were tested to determine the optimum conditions for ex vitro rooting of microshoots. The best result was accomplished with a pulse treatment of IBA (100 μM) applied to the basal end of the microshoot for 30 min, followed by transfer to plastic cups containing soilrite, and eventually established in natural soil with an 85% survival rate. The determination of activities of antioxidative enzymes (superoxide dismutase, ascorbate peroxidase, catalase, and glutathione reductase) revealed involvement of these enzymes in shoot differentiation and development. All of these activities were interlinked with each other and played significant roles in the scavenging of toxic free radicals. Intersimple sequence repeat DNA analysis was carried out using five primers. The amplification products were monomorphic in micropropagated plants, similar to those of the mother plant. No polymorphisms were detected revealing the genetic integrity of the micropropagated plants.  相似文献   
284.
In higher plants, recent advances in plant molecular genetics, combined with modern physiological and biochemical studies, have expanded our understanding of the regulatory mechanisms controlling the primary steps of inorganic nitrogen assimilation and the subsequent biochemical pathways involved in nitrogen supply and recycling for higher plant metabolism, growth and development. In this presentation, we describe improvements in our understanding of the molecular controls of nitrogen assimilation through the use of transgenic plants and the study of genetic variability in model and crop species. To illustrate this research programme, the physiological impact of modified gene expression, using either transgenic plants or different genotypes, was studied using 15N-labelling experiments in order to monitor the influx of nitrate or ammonia and its subsequent incorporation into amino acids.  相似文献   
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