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This study investigated the effect of dietary supplementation of probiotic Pedicoccus acidilactici and nucleotide (separately or combined) on growth performance, intestinal microbiota, hemato-immunological parameters, and immunity response in goldfish (Carassius auratus). Fish (average weight 5–6 g) were acclimatized and divided into eight experimental diets supplemented with P. acidilactici of different concentrations (0.1, 0.2, and 0.3% diet) and nucleotides (0 and 0.5% diet) for 6 months. Fish fed with experimental diets showed significant differences in terms of final weight, weight gain, feed conversion ratio, daily growth rate, and condition factor when compared to control diet (P < 0.05). Fish fed with probiotic (0.3%) separately and combined with nucleotide (0.5%) had highest RBC and WBC when compared to other diets (P < 0.05), while the highest values for Hb and Hct as well as total protein, glucose, albumin, and globulin were observed in probiotic (0.2%) and nucleotide (0.5%) combined diet. Serum lysozyme and anti-protease activities were significantly higher in probiotic (0.1 and 0.2%) and nucleotide (0.5%) combined diets. Similarly, these two diets combined showed the highest colonization of P. acidilactici when compared to other diets. In conclusion, combined dietary probiotic and nucleotide improve the growth performance, hemato-biochemical parameters, and intestine growth in C. auratus.  相似文献   
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Four airport malaria cases have been observed in the vicinity of the Roissy-Charles-de-Gaulle International Airport, Paris, France. These cases were geographically very close to each other and clustered in a short period of time during the summer of 1999. The phenotype and genotype of the Plasmodium falciparum isolates obtained from these patients were determined in order to know whether a single mosquito could have infected more than one subject. The genomic characterisation of isolates was performed using the polymorphic markers merozoite surface protein 1 (Msp 1) and merozoite surface protein 2 (Msp 2) genes, the kappa and omega repeats domains of cg2 and the dihydrofolate reductase (DHFR) genotypes. Results showed identical genotypes for isolates 1, 2 and 4 whereas the genotype of isolate 3 differed at one locus. The molecular analysis was consistent with the hypothesis that all patients could have been bitten by the same mosquito and that patient 3, may have received a different clone and an additional species. In vitro susceptibility data did not confirm or rule out this hypothesis because isolates had the same profile of susceptibility to the tested drugs.  相似文献   
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Msp-1 and Msp-2 genes, each present as a unique copy in the genome of Plasmodium, contain polymorphic repeats in bloc 2. We studied allelic polymorphism of Msp-1 and Msp-2 by amplifying bloc 2 with a fluorescent primer, and analysing the fragment generated. We validated this method by mixing two cloned strains: chloroquine-susceptible HB3-Honduras and chloroquine-resistant FCM29-Cameroon. This method was then used to quantify the clones in natural isolates of 19 infected persons during quinine treatment. The fragment analysis method detects efficiently clone numbers and the proportions of each in isolates.  相似文献   
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The presence of the genes for Escherichia coli adherence factor (EAF), attaching and effacing lesion (eae) and bundle-forming pili (bfp) in 72 strains identified as enteropathogenic E. coli (EPEC) by slide agglutination was evaluated using hybridization and PCR. The adherence property of these strains was assayed using 3h HeLa cells adherence assay. The results obtained indicated that virulence-associated genes were present in 65% of the strains but only ten (13.9%) isolates were positive for all the three markers (typical EPEC), 37 (51.4%) isolates carried either one or two of these determinants (atypical EPEC) and the remaining 25 (34.7%) were negative for all these genes. In vitro adherence assay showed that 44 (61.1%) strains adhered to HeLa cells with a defined pattern, 13 (18.1%) isolates adhered loosely with no definite pattern and the remaining 15 (20.8%) were non-adherent. Analysis of the results showed a statistically significant association between the presence of the virulence-related genes with adherence of the strains with a defined pattern (P相似文献   
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High-pressure hydrocephalus: a novel analytical modeling approach   总被引:1,自引:0,他引:1  
Hydrocephalus is an abnormal accumulation of cerebrospinal fluid (CSF) within ventricles and subarachnoid space (SAS) as a result of disturbances in secretion or absorption procedures. It is believed that arachnoid villi cells, which are microscopic projections of pia-arachnoid mater that extend into venous channels in sagittal sinus, are the main sites for CSF absorption, but it is tempting to speculate that a significant portion of CSF is removed from the SAS by nasal lymphatic vessels around olfactory nerve. Thus, in this paper, we propose an analytical model of CSF-lymphatic-blood circulation, in which these two output pathways for CSF absorption have been considered. Mathematical relations governing the pressures in different interacting compartments of the brain are considered. In addition, for increasing the similarity of our model to the physiological conditions, the bulk flow mechanism, which is supposed to occur during CSF absorption, has been considered in our model. We used our model to simulate hydrocephalus. The results indicate that the lymphatic disorders have more considerable effect in decreasing CSF absorption, compared to the disturbances in arachnoid villi cells. Based on our modeling, we believe that disorders in lymphatic pathway may be a cause of high-pressure hydrocephalus. Surely experimental studies are required to validate our hypothesis.  相似文献   
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Biomechanics and Modeling in Mechanobiology - Detailed knowledge about the mechanical properties of brain can improve numerical modeling of the brain under various loading conditions. The success...  相似文献   
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