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21.
R.H. MADDEN, L. MORAN AND P. SCATES. 1996. Based on a 10-mer primer (5'- CCTGTTAGCC-3'), a random amplified polymorphic DNA (RAPD) method for typing Campylobacter coli isolated from pigs was developed. The method proved effective with a high discrimination and good reproducibility. In contrast with serotyping no untypable strains were found out of a total of 269 isolates (veterinary, food and clinical) examined. The method was also successfully applied to typing Campylobacter jejuni from a similar range of sources. 相似文献
22.
A genetic linkage map for Pinus radiata based on RFLP, RAPD, and microsatellite markers 总被引:7,自引:0,他引:7
M. E. Devey J. C. Bell D. N. Smith D. B. Neale G. F. Moran 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(6):673-679
A genetic linkage map for radiata pine (Pinus radiata D. Don) has been constructed using segregation data from a three-generation outbred pedigree. A total of 208 loci were analyzed including 165 restriction fragment length polymorphism (RFLP), 41 random amplified polymorphic DNA (RAPD) and 2 microsatellite markers. The markers were assembled into 22 linkage groups of 2 or more loci and covered a total distance of 1382 cM. Thirteen loci were unlinked to any other marker. Of the RFLP loci that were mapped, 93 were detected by loblolly pine (P. taeda L.) cDNA probes that had been previously mapped or evaluated in that species. The remaining 72 RFLP loci were detected by radiata pine probes from a PstI genomic DNA library. Two hundred and eighty RAPD primers were evaluated, and 41 loci which were segregating in a 11 ratio were mapped. Two microsatellite markers were also placed on the map. This map and the markers derived from it will have wide applicability to genetic studies in P. radiata and other pine species. 相似文献
23.
24.
Sphyrion lumpi is a sexually dimorphic, parasitic copepod which causes significant losses in fisheries in the North Atlantic. Studies involving both light and scanning electron microscopy revealed important details of the external morphology of both sexes that are discussed in relation to other members of the family Sphyriidae. Conclusions are drawn regarding the life cycle of S. lumpi. The present finding of this parasite on Urophycis tenuis constitutes a new host record. 相似文献
25.
Deforestation and land use in the Brazilian Amazon 总被引:4,自引:0,他引:4
Emilio F. Moran 《Human ecology: an interdisciplinary journal》1993,21(1):1-21
Deforestation in the Brazilian Amazon was less than 1% before 1975. Between 1975 and 1987 the rate increased exponentially. By 1985, world opinion and attention to the destruction of the richest biome on earth led to elimination of some of the major incentives that had fueled deforestation. Favorable credit policies for cattle ranchers, rather than population growth, explains the process of deforestation in the Brazilian Amazon. The paper suggests other actions that may be taken to reduce deforestation, and examines the rapid growth rates of secondary successional species in a colonization area. 相似文献
26.
Richard Safford Marilyn T. Moran Jacqueline De Silva Susan J. Robinson Susan Moscow Carl D. Jarman Antoni R. Slabas 《Transgenic research》1993,2(4):191-198
Medium chain hydrolase (MCH) is an enzyme which regulates the chain length of fatty acid synthesis specifically in the mammary gland of the rat. During lactation, MCH interacts with fatty acid synthase (FAS) to cause premature release of acyl chains, thus providing medium chain fatty acids for synthesis of milk fat. In this study we have investigated the ability of rat MCH to interact with the phylogenetically more distant FAS structure present in plant systems and to cause a perturbation of fatty acid synthesis. Inin vitro experiments, addition of purified MCH to rapeseed homogenates was found to cause a significant perturbation of fatty acid synthesis towards medium chain length products. The rat MCH gene was expressed in transgenic oilseed rape using a seed specific rape acyl carrier protein (ACP) promoter and a rape ACP plastid targeting sequence. Western analysis showed MCH protein to be present in transgenic seed and for its expression to be developmentally regulated in concert with storage lipid synthesis. The chimaeric preprotein was correctly processed and immunogold labelling studies confirmed MCH to be localized within plastid organelles. However, fatty acid analysis of oil from MCH-expressing rape seed showed no significant differences to that from control seed. 相似文献
27.
An integrated genetic linkage map for eucalypts using RFLP,RAPD and isozyme markers 总被引:19,自引:0,他引:19
M. Byrne J. C. Murrell B. Allen G. F. Moran 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,91(6-7):869-875
An integrated genetic linkage map for E. nitens was constructed in an outbred three-generation pedigree. Analysis of 210 RFLP, 125 RAPD and 4 isozyme loci resulted in 330 markers linked in 12 linkage groups covering 1462 cM (n=11 in eucalypts). The 12th linkage group is comprised of only 5 markers and will probably coalesce with another linkage group when further linked loci are located. Co-dominant RFLP loci segregating in both parents were used to integrate linkages identified in the male and female parents. Differences in recombination frequencies in the two parents were observed for a number of pairs of loci, and duplication of sequences was identified both within and between linkage groups. The markers were distributed randomly across the genome except for the RFLPs in linkage group 10 and for some loci showing segregation distortion, which were clustered into three regions of the map. The use of a large number of co-dominant RFLP loci in this map enables it to be used in other pedigrees of E. nitens and forms a basis for the detection and location of QTL in E. nitens and other eucalypt species. 相似文献
28.
Moran, R.C. & Øllgaard, B. 1995. Six new species of ferns (Polypodiopsida) from Ecuador. - Nord. J. Bot. 15: 177–185. Copenhagen. ISSN 0107–055X.
The following species of ferns from Ecuador are described as new: Blechnum mono-morphum. Bolbitis riparia, Hecistopteris pinnatifida, Hymenophyllum hemidimorphum, Polypodium latissimum , and Saccoloma laxum . 相似文献
The following species of ferns from Ecuador are described as new: Blechnum mono-morphum. Bolbitis riparia, Hecistopteris pinnatifida, Hymenophyllum hemidimorphum, Polypodium latissimum , and Saccoloma laxum . 相似文献
29.
Melaleuca alternifolia andM. linariifolia are commercially important Australian species harvested for their essential oils. Both species have relatively narrow and disjunct distributions on the central coast of eastern Australia. Variation in the chloroplast genome was assessed for eight individuals from each of twelve populations, representing the species' geographic range. Low nucleotide diversity withinM. alternifolia contrasted with high nucleotide diversity inM. linariifolia. CpDNA data are consistent with the southern population ofM. alternifolia being a hybrid population withM. linariifolia. The two species are sympatric in this region. Variation inM. linariifolia was geographically structured, with northern populations differing from southern populations by seven restriction site mutations, five length mutations and an inversion. There was no evidence of hybridisation of the cp genome of northernM. linariifolia with the partially sympatric speciesM. trichostachya. Intra- and interspecific variation in the chloroplast genomes ofM. alternifolia, M. linariifolia, andM. trichostachya indicate considerable potential for the use of intraspecific cpDNA studies in examining phylogenetic relationships in melaleucas. 相似文献