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791.
Elderly people use often and in an appropriate way the Emergency Department (ED). However, we don’t dispose of evidences that demonstrate utility of a specific model of geriatric assessment (GA) applied in ED. Nowadays; GA in ED should be used being adapted to the environment and with some clear objectives that allow to carry out a multidimensional diagnosis and to establish therapeutic priorities. GA contributes benefits in the continuity of care on the part of the Primary Attention when elderly people are discharged from an ED.  相似文献   
792.
Karyotypic studies with conventional staining have been unsuccessful due to the uniformity of Capsicum chromosomes. In this study, we found diagnostic chromosome characters that permit to characterize cultivars; this is the first cytological characterization of both rDNAs (18S and 5S) in a species of Capsicum using a genus-specific probe and the most exhaustive in C. annuum to date. The heterochromatic banding patterns enabled us to identify cultivars, and fluorescent in situ hybridization (FISH) showed one 5S rDNA locus largely conserved within the cultivars, whereas high variation in the number of 18S rDNA loci was observed. One of the most obvious differences is the presence of an additional active nucleolar organizer region in pair #12 and the dispersal of inactive 18S rDNA signals. These results indicate that fluorochrome banding together with silver impregnation and FISH procedures are very useful for the identification of chromosomes and the interpretation of chromosomal variation between cultivars. The functional role of this variation is still uncertain, but our results show that copy number variation of repetitive DNA during the course of evolution might provide an excellent experimental system for studying genome rearrangements accompanying functional divergence in domesticated C. annuum.  相似文献   
793.
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The content of sialic acid bound to the sinusoidal region of plasma membrane during the prereplicative phase after the intravenous injection of a solution containing triiodothyronine, amino acids, glucagon and heparin (T.A.G.H. solution) has been measured. The results obtained show that an important decrease in sialic acid content is produced as it occurs in the hepatic cells of hepatectomized animals. In order to know if sialidase activity is involved in the decrease of sialic acid content during liver regeneration, the activity of sinusoidal plasma membrane sialidases during the prereplicative phase after the partial hepatectomy has been studied. No modifications of sialidase activity were detected during this period of time indicating that this decrease in sialic acid content has to be produced by other mechanisms such as diminution in the synthesis of precursor molecules. On the other hand due to the importance of Ca2+-calmodulin complexes in the activation of the hepatic cell proliferation the possible implication of this complex on the loss of sialic acid, observing the effect of trifluoperazine (inhibitor of Ca2+-calmodulin complexes) during the prereplicative phase of liver regeneration has been studied. The results show a delay in the decrease of the amount of sugar studied from 10 to 12 hours compared to the results obtained with the hepatectomized rats that have not received trifluoperazine.  相似文献   
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International Microbiology - The life cycle of Ustilago maydis involves alternation of a haploid saprophytic yeast-like stage and a dikaryotic hyphal virulent form. Under in vitro conditions,...  相似文献   
797.
Microbial emulsifiers are compounds employed in primary mechanisms for bioremediation of petroleum and other hydrocarbon pollutants from the environment. Although emulsifiers of biological origin are produced by microorganisms generally in response to growth on hydrocarbons, Aspergillus niger MYA 135 produced a bioemulsifier during fermentation in a sucrose-based culture medium at an initial pH of 5.0 and at 30°C. The production of bioemulsifiers can be strongly influenced by environmental factors. In this connection, a study of the effect of initial pH, the incubation temperature and presence of CaCl2 or FeCl3 in the culture medium was conducted. Emulsification index was increased by 112 and 206% at an initial pH 2.0 or in medium supplemented with FeCl3, respectively. On the other hand, emulsifying ability of Aspergillus niger supernatants was detected during the exponential phase, suggesting that bioemulsifiers accumulation and microbial growth would be related. Interestingly, this study suggests that iron and/or phosphate ions would play a key role in maintaining the emulsifying ability. Finally, factorial design was also employed to study the effects of the initial pH, the presence of FeCl3 and the concentration of KH2PO4 on the emulsification index.  相似文献   
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Trace elements exert a strong influence on immune function. Debilitated humoral and cellular immune responses may impair virus clearance in infected organisms, and favor the generation of virus variants with altered biological properties. The population size in evolving viral quasispecies, as well as increased mutagenesis trigered by oxidative stress, may contribute to altering the outcome of quasispecies evolution in infected hosts. The genetic plasticity of RNA viruses is one of the main obstacles for the control of the diseases they cause and probably a major force in the emergence of new viral pathogens. Recent results suggest links between nutritional deficiencies and the generation of variant viruses, a possibility that is addressed in the present article.  相似文献   
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