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201.
Administration of morphine or ethanol to rats produces a decrease in regional brain calcium in vivo. This effect is selectively antagonized by the stereospecific narcotic antagonist naloxone. Reserpine and the dopamine-acetaldehyde conjugate salsolinol also produce a depletion of regional brain calcium, but only the salsolinol depletion is antagonized by naloxone. Experiments with naloxone provide evidence for two calcium-sensitive pools in the central nervous system. 相似文献
202.
Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens. 相似文献
203.
Serratosa MP Marquez A Lopez-Toledano A Medina M Merida J 《Journal of agricultural and food chemistry》2011,59(5):1882-1892
The purpose of this work was to study the variation of phenol compounds, as measured by HPLC, during the chamber drying under controlled temperature conditions of red grapes of the Merlot and Tempranillo varieties in relation to antioxidant activity. Both lipophilic and hydrophilic antioxidant activities in these grapes increased during the drying process; the former was measured via proton transfer in the coupled oxidation reaction between linoleic acid and β-carotene, and the second via electron transfer in the DPPH assay. The hydrophilic component was invariably greater in Tempranillo grapes, and so was the lipophilic component in Merlot grapes. Only the increase in hydrophilic antioxidant activity obtained a significant correlation with the phenolic compounds during the drying process. However, based on the phenolic fraction analysis, this result was primarily due to phenolic polymers and, to a lesser extent, also to phenolic acids, flavans, and some flavonols and anthocyans. 相似文献
204.
Francisco Joel Jahuey‐Martínez Gaspar Manuel Parra‐Bracamonte Ana María Sifuentes‐Rincn Victor Ricardo Moreno‐Medina 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(5):378-389
Charolais cattle are one of the most important breeds for meat production worldwide; in México, its selection is mainly made by live weight traits. One strategy for mapping important genomic regions that might influence productive traits is the identification of signatures of selection. This type of genomic features contains loci with extended linkage disequilibrium (LD) and homozygosity patterns that are commonly associated with sites of quantitative trait locus (QTL). Therefore, the objective of this study was to identify the signatures of selection in Charolais cattle genotyped with the GeneSeek Genomic Profiler Bovine HD panel consisting of 77 K single nucleotide polymorphisms (SNPs). A total 61,311 SNPs and 819 samples were used for the analysis. Identification of signatures of selection was carried out using the integrated haplotype score (iHS) methodology implemented in the rehh R package. The top ten SNPs with the highest piHS values were located on BTA 4, 5, 6 and 14. By identifying markers in LD with top ten SNPs, the candidate regions defined were mapped to 52.8–59.3 Mb on BTA 4; 67.5–69.3 on BTA 5; 39.5–41.0 Mb on BTA 6; and 26.4–29.6 Mb on BTA 14. The comparison of these candidate regions with the bovine QTLdb effectively confirmed the association (p < 0.05) with QTL related to growth traits and other important productive traits. The genomic regions identified in this study indicated selection for growth traits on the Charolais population via the conservation of haplotypes on various chromosomes. These genomic regions and their associated genes could serve as the basis for haplotype association studies and for the identification of causal genes related to growth traits. 相似文献