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1.
Comparative phytochemical analyses of hydroalcoholic (50% EtOH) extracts from roots of S. miltiorrhiza (SM) and S. przewalskii (SP) were performed using two complementary LC–MS systems: the first system HPLC-DAD-MSn an ion trap mass spectrometer and the second system consisted high resolution MS/MS Orbitrap mass spectrometer. The individual compounds were identified using a previously published approach via comparison of the exact molecular masses, mass spectra and retention times to those of standard compounds, online available databases and literature data. Moreover, the determination of antioxidative activities of extracts by DPPH and FRAP methods was carried out. Analysis allowed to identify 39 chemical compounds in extracts from both species. Extract from root of SP differs from SM in the presence of several metabolites such as: przewalskinic acid and their derivatives, przewaquinone C, przewaquinonate A, glycosides of rosmarinic acid, methyltanshinonate, whereas tanshinones, salvianolic acids and lithospermic acids occurred in both species. Moreover, it was shown that hydroalcoholic extract from roots of SM exerted stronger antioxidant properties in a FRAP test (max. 323.92 μM Fe2+/L) and in DPPH test (max. 78.64 nM TE) in comparison with SP extract.  相似文献   
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Accuracy of predicting genomic breeding values for carcass merit traits including hot carcass weight, longissimus muscle area (REA), carcass average backfat thickness (AFAT), lean meat yield (LMY) and carcass marbling score (CMAR) was evaluated based on 543 Angus and 400 Charolais steers genotyped on the Illumina BovineSNP50 Beadchip. For the genomic prediction within Angus, the average accuracy was 0.35 with a range from 0.32 (LMY) to 0.37 (CMAR) across different training/validation data‐splitting strategies and statistical methods. The within‐breed genomic prediction for Charolais yielded an average accuracy of 0.36 with a range from 0.24 (REA) to 0.46 (AFAT). The across‐breed prediction had the lowest accuracy, which was on average near zero. When the data from the two breeds were combined to predict the breeding values of either breed, the prediction accuracy averaged 0.35 for Angus with a range from 0.33 (REA) to 0.39 (CMAR) and averaged 0.33 for Charolais with a range from 0.18 (REA) to 0.46 (AFAT). The prediction accuracy was slightly higher on average when the data were split by animal's birth year than when the data were split by sire family. These results demonstrate that the genetic relationship or relatedness of selection candidates with the training population has a great impact on the accuracy of predicting genomic breeding values under the density of the marker panel used in this study.  相似文献   
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In microbial control of insect pests, the dose of pathogen that a subject actually receives varies because of variation in individual intakes. Variation in intake of a given concentration is equivalent to varying the concentration for a given intake. The main effect of such variation is to flatten the dose-response curve. If the dose-variation is known, a correction for this effect can be made; new estimates for the slope and intercept of the probit line are given. However, the correction increases the variance of the estimates. The theory is illustrated with an example in which the diamond-backed month, Plutella xylostella, was fed varying doses of the specific granulosis virus PxGV; intake assays using similar larvae showed the coefficient of variation of intake volume to be about 40%. Simulation studies showed that correction may be practically important only for the estimation of extreme percentiles, e.g. LD95s.  相似文献   
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This study aimed to evaluate the efficacy of chitosan-silver nanocomposites in the treatment of experimentally infested pigeons with Pseudolynchia canariensis (P. canariensis) with evaluation of different immunological parameters before and after treatment. Therefore, fourteen birds were divided into 2 groups; group1(infested group including 12 birds) which subdivided into 6 sub-groups experimentally infested pigeons 2 pigeons each, and five group of them were treated with chitosan-silver nanocomposites and sub-group number 6 was treated with deltamethrin while, group 2 including two pigeons were kept as control negative ones. P. canariensis flies distributed under the wing and /or under the tail in infested group and these pigeons showed significantly lower RBCs and higher WBCs than that in non-infested pigeons. The cell mediated immune response against experimentally infested pigeons with P. canariensis was studied. P. canariensis infestation in pigeons have a negative impact on pigeon’s blood parameters, increase TNF-α and IL-1β cytokines levels. This study cleared out the role of P. canariensis in the induction of a case of oxidative stress indicated by high level of nitric oxide and malondialdehyde (MDA) with low antioxidant capacity in shape of reduced zinc concentration in the sera of experimentally infested pigeon. Chitosan-silver nanocomposite has a promising effect in the elimination of P. canariensis infestation in pigeons.  相似文献   
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Protein kinase C phosphorylates the neurone-specific protein B-50 at a single Ser41 residue, which is also the point for a major proteolytic cleavage in vitro, and probably in vivo, that produces a B-50 phosphorylation-inhibiting N-terminal fragment and a large C-terminal metabolite B-60 (B-50(41-226]. The intact purified protein will bind to calmodulin in the absence of calcium, but the interaction has an absolute requirement for dephospho-B-50. In an attempt to unify two aspects of B-50 biochemistry, we have examined the interaction of B-50 binding to calmodulin and B-50 proteolysis. HPLC- and affinity-purified B-50 bound to calmodulin, but purified B-60 did not. To ensure that this effect was not due to the phosphorylation state of pure, isolated B-60, the metabolite was generated in vitro using a Triton extract of synaptosomal plasma membranes, which contains the as yet uncharacterized B-50 protease. B-60 derived from dephospho-B-50 also failed to bind calmodulin. The results demonstrate a direct connection between B-50 binding to calmodulin and B-50 proteolysis. The position of the proposed calmodulin-binding domain within intact B-50 is discussed in light of the failure of calmodulin to bind B-60.  相似文献   
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Synopsis Seawater adaptability of wild pink salmon, Oncorhynchus gorbuscha, alevins was investigated using 96 h LC50 test, muscle sodium level and weight loss tests. Five temperature (2, 6, 9, 13 and 16°C) and two yolk groups were analysed during the beginning, the middle and the end of downstream migration. Both temperature and amount of residual yolk affected seawater adaptability. The computation of muscle sodium levels and weight loss after a short term (3–12 h) seawater challenge test may be a convenient method to estimate the seawater adaptability of fish too small to allow analysis of blood sodium concentration.  相似文献   
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Liver plasma membranes prepared from genetically diabetic (db/db) mice expressed levels of Gi α-2, Gi α-3 and G-protein β-subunits that were reduced by some 75, 63 and 73% compared with levels seen in membranes from lean animals. In contrast, there were no significant differences in the expression of the 42 and 45 kDa forms of Gs α-subunits. Pertussis toxin-catalysed ADP-ribosylation of membranes from lean animals identified a single 41 kDa band whose labelling was reduced by some 86% in membranes from diabetic animals. Cholera toxin-catalysed ADP-ribosylation identified two forms of Gs α-subunits whose labelling was about 4-fold greater in membranes from diabetic animals compared with those from lean animals. Maximal stimulations of adenylyl cyclase activity by forskolin (100 μM), GTP (100 μM), p[NH]ppG (100 μM), NaF (10 mM) and glucagon (10 μM) were similar in membranes from lean and diabetic animals, whereas stimulation by isoprenaline (100 μM) was lower by about 22%. Lower concentrations (EC50-60 nM) of p[NH]ppG were needed to activate adenylyl cyclase in membranes from diabetic animals compared to those from lean animals (EC50-158 nM). As well as causing activation, p[NH]ppG was capable of eliciting a pertussis toxin-sensitive inhibitory effect upon forskolin-stimulated adenylyl cyclase activity in membranes from both lean and diabetic animals. However, maximal inhibition of adenylyl cyclase activity in membranes from diabetic animals was reduced to around 60% of that found using membranes from lean animals. Pertussis toxin-treatment in vivo enhanced maximal stimulation of adenylyl cyclase by glucagon, isoprenaline and p[NH]ppG through a process suggested to be mediated by the abolition of functional Gi activity. The lower levels of expression of G-protein β-subunits, in membranes from diabetic compared with lean animals, is suggested to perturb the equilibria between holomeric and dissociated G-protein subunits. We suggest that this may explain both the enhanced sensitivity of adenylyl cyclase to stimulation by p[NH]ppG in membranes from diabetic animals and the altered ability of pertussis and cholera toxins to catalyse the ADP-ribosylation of G-proteins in membranes from these two animals.  相似文献   
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