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11.
Selection for increased resistance to Salmonella colonisation and excretion could reduce the risk of foodborne Salmonella infection. In order to identify potential loci affecting resistance, differences in resistance were identified between the N and 61 inbred lines and two QTL research performed. In an F2 cross, the animals were inoculated at one week of age with Salmonella enteritidis and cloacal swabs were carried out 4 and 5 wk post inoculation (thereafter called CSW4F2 and CSW4F2) and caecal contamination (CAECF2) was assessed 1 week later. The animals from the (N × 61) × N backcross were inoculated at six weeks of age with Salmonella typhimurium and cloacal swabs were studied from wk 1 to 4 (thereafter called CSW1BC to CSW4BC). A total of 33 F2 and 46 backcross progeny were selectively genotyped for 103 and 135 microsatellite markers respectively. The analysis used least-squares-based and non-parametric interval mapping. Two genome-wise significant QTL were observed on Chromosome 1 for CSW2BC and on Chromosome 2 for CSW4F2, and four suggestive QTL for CSW5F2 on Chromosome 2, for CSW5F2 and CSW2BC on chromosome 5 and for CAECF2 on chromosome 16. These results suggest new regions of interest and the putative role of SAL1.  相似文献   
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16S rRNA Phylogeny of Sponge-Associated Cyanobacteria   总被引:5,自引:0,他引:5       下载免费PDF全文
Phylogenetic analyses of 16S rRNA sequences of sponge-associated cyanobacteria showed them to be polyphyletic, implying that they derived from multiple independent symbiotic events. Most of the symbiont sequences were affiliated to a group of Synechococcus and Prochlorococcus species. However, other symbionts were related to different groups, such as the Oscillatoriales.  相似文献   
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Listeria spp. were found in most treated waters (84.4%) and raw sludge (89.2%) of six French urban wastewater treatment plants and one composting facility, examined monthly over a 1-year period. Most strains belonged to Listeria monocytogenes, serotypes 4b/4e being predominant. Sludge composting and liming reduced or prevented Listeria contamination.  相似文献   
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E N L'Abbé  M Loots  J H Meiring 《HOMO》2005,56(2):197-205
The Pretoria Bone Collection began with the inception of the Department of Anatomy and the Medical School at the University of Pretoria in August 1942. Since then the collection has grown from a student aid to a resource for research. In the year 2000, the Pretoria Bone Collection was reorganised. The research material was divided into skulls, complete postcranial and incomplete postcranial remains. The collection presently contains 290 complete skeletons, 704 complete skulls and 541 complete postcranial remains. This paper presents information on the composition of this collection and hopes to heighten both national and international awareness of the collection and research opportunities in South Africa.  相似文献   
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Myzostomids are minute, soft-bodied, marine worms associated with echinoderms since the Carboniferous. Due to their long history as host-specific symbionts, they have acquired a highly derived body plan that obscures their phylogenetic affinities to other metazoans. Because certain organs are serially arranged a closer relationship between polychaetes and myzostomids has repeatedly been discussion. We presented here a review on the ultrastructure of myzostomids with the most recent analyses that concern their phylogenetic position. The ultrastructure of the integument, digestive system, excretory system and nervous system are summarized. Unpublished information on the gametogenesis and reproductive systems of myzostomids are also exposed with a view on their reproductive process.  相似文献   
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Three new water soluble titanocene–aminoacid complexes have been synthesized via the reaction of Cp2TiCl2 and two equivalents of aminoacid (L) in methanol, affording [Cp2TiL2]Cl2, L=L-cysteine (2), D-penicillamine (3) and L-methionine (4). These complexes have been characterized by 1H, IR and UV-Vis spectroscopies, elemental analysis and cyclic voltammetry. Kinetic studies of ligand hydrolysis have been monitored at low pH using UV-Vis and 1H NMR spectroscopies to assess their stability in aqueous solution. At low pH, aminoacid ligands are lost one order of magnitude faster than cyclopentadienyl. However, at physiological pH, in Tris buffer solution, the complexes decompose rapidly to form an insoluble titanium compound. The affinity of these complexes to apo-transferrin was also investigated to elucidate how the ancillary aminoacid ligands affect the titanium intake by apo-transferrin.Electronic Supplementary Material Supplementary material is available for this article at  相似文献   
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