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101.
Rates and dates of divergence between AIDS virus nucleotide sequences 总被引:28,自引:3,他引:25
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AS Glen D Anderson CJ Veltman PM Garvey M Nichols 《New Zealand journal of zoology.》2016,43(2):127-137
A major challenge in controlling overabundant wildlife is monitoring their populations, particularly as they decline to very low density. Camera traps and wildlife detector dogs are increasingly being used for this purpose. We compared the cost-effectiveness of these two approaches for detecting feral cats (Felis catus) on two pastoral properties in Hawke's Bay, North Island, New Zealand. One property was subject to intensive pest removal, while the other had no recent history of pest control. Camera traps and wildlife detector dogs detected cats at similar rates at both sites. The operating costs of each method were also comparable. We identify a number of advantages and disadvantages of each technique, and suggest priorities for further research. 相似文献
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Complementation of the inability of Lactobacillus strains to utilize D-xylose with D-xylose catabolism-encoding genes of Lactobacillus pentosus. 总被引:3,自引:0,他引:3 下载免费PDF全文
M Posno P T Heuvelmans M J van Giezen B C Lokman R J Leer P H Pouwels 《Applied microbiology》1991,57(9):2764-2766
The inability of two Lactobacillus strains to ferment D-xylose was complemented by the introduction of Lactobacillus pentosus genes encoding D-xylose isomerase, D-xylulose kinase, and a D-xylose catabolism regulatory protein. This result opens the possibility of using D-xylose fermentation as a food-grade selection marker for Lactobacillus spp. 相似文献
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Anne-Ga?lle Biacabe Jorg G Jacobs Anna Bencsik Jan PM Langeveld Thierry GM Baron 《朊病毒》2007,1(1):61-68
We previously reported that some cattle affected by bovine spongiform encephalopathy (BSE) showed distinct molecular features of the protease-resistant prion protein (PrPres) in Western blot, with a 1–2 kDa higher apparent molecular mass of the unglycosylated PrPres associated with labelling by antibodies against the 86–107 region of the bovine PrP protein (H-type BSE). By Western blot analyses of PrPres, we now showed that the essential features initially described in cattle were observed with a panel of different antibodies and were maintained after transmission of the disease in C57Bl/6 mice. In addition, antibodies against the C-terminal region of PrP revealed a second, more C-terminally cleaved, form of PrPres (PrPres #2), which, in unglycosylated form, migrated as a ≈ 14 kDa fragment. Furthermore, a PrPres fragment of ≈7 kDa, which was not labelled by C-terminus-specific antibodies and was thus presumed to be a product of cleavage at both N- and C-terminal sides of PrP protein, was also detected. Both PrPres #2 and ≈7 kDa PrPres were detected in cattle and in C57Bl/6 infected mice. These complex molecular features are reminiscent of findings reported in human prion diseases. This raises questions regarding the respective origins and pathogenic mechanisms in prion diseases of animals and humans.Key Words: prion, BSE, Creutzfeldt-Jakob, Gerstmann-Sträussler-Scheinker, Western blot, amyloid 相似文献
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Lokman Shamsudin 《Journal of applied phycology》1992,4(4):371-378
The total ash, chlorophyll, phaeopigment, lipid and fatty acid contents of three microalgae (the diatomsChaetoceros calcitrans, Skeletonema costatum and the prymnesiophyteIsochrysis galbana) used in tropical Malaysian penaeid mariculture were studied. The axenic laboratory cultures were grown in f-2 medium, while outdoor cultures were grown in a commercial medium designed for optimum nutrition in tropical outdoor aquaculture operations. Considerable amounts (3–9% of the total fatty acid) of the polyunsaturated fatty acid 20:5w3 (eicosapentaenoic acid) were present in the diatoms; very small amounts were also found inI. galbana. Lipid contents were three to five times higher than chlorophylla. There was an increase with culture age in the relative proportion of total C18 and C20 fatty acid components. The algae contained the w3-polyunsaturated fatty acids (PUFA) necessary for the growth and survival rate of the prawn larvae. However, onlyChaetoceros calcitrans grew well under the conditions of temperature and salinity in the hatchery. 相似文献