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41.
Fr. 《Journal of pest science》1940,16(12):143-144
Ohne Zusammenfassung 相似文献
42.
European Journal of Forest Research - 相似文献
43.
44.
Fr. 《Journal of pest science》1938,14(7):83-83
Ohne Zusammenfassung 相似文献
45.
Marine fisheries target and catch fish both for direct human consumption (DHC) as well as for fishmeal and fish oil, and other products. We derived the fractions used for each for 1950–2010 by fishing country, and thus provide a factual foundation for discussions of the optimal use of fisheries resources. From 1950 to 2010, 27% (~20 million tonnes annually) of globally reconstructed marine fisheries landings were destined for uses other than DHC. Importantly, 90% of fish destined for uses other than DHC are food‐grade or prime food‐grade fish, while fish without a ready market for DHC make up a much smaller proportion. These findings have implications for how we are using fish to feed ourselves or, more appropriately, how we are not using fish to feed ourselves. 相似文献
46.
Onivaldo Randig Frédéric Leroy Philippe Castagnone-Sereno 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(6):639-643
Random amplified polymorphic DNA fingerprinting was performed on single females of root-knot nematodes, Meloidogyne spp., using a new procedure for DNA isolation. One-fourth of the total DNA amount isolated from a single female proved to be sufficient as a template in a polymerase chain reaction. Electrophoretic patterns of the amplified fragments were reproducible between replicates from a single female or sister females from the same progeny, and identical to those obtained with genomic DNA purified from a large number of nematodes. Moreover, a comparative analysis over three successive generations showed stability of the amplification patterns, thus demonstrating the utility of this procedure for epidemiological and ecological studies on root-knot nematodes. 相似文献
47.
A. Bertaccini J. Fránová S. Paltrinieri M. Martini M. Navrátil C. Lugaresi J. Nebesárová M. Simkova 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(5):487-493
During the summer 1996, twelve of twenty-eight leek plants located in a garden near eské Budjovice, South Bohemia exhibited symptoms typical of diseases associated with phytoplasmas. In summer 1998 similar symptoms were detected in leek plants in a field used for seed production located in Romagna, North Italy. In both cases the plants were established in the spring of the previous year. Plants showed flower abnormalities: stamen elongation, anther sterility, pistil proliferation, as well as poor, if any, seed production. Phytoplasma-like structures were detected by scanning and transmission electron microscopy in phloem sieve elements in the Czech diseased plants, but not in healthy ones. Nested-PCR amplifications of extracted DNA with phytoplasma-specific oligonucleotide primer pairs confirmed the presence of phytoplasmas in these plants at low concentrations. Restriction fragment length polymorphism analyses of amplified ribosomal sequences allowed the identification of detected phytoplasmas: all the samples from the Czech Republic contained aster yellows related phytoplasmas (16SrI-B) while in the Italian samples aster yellows related phytoplasmas (16SrI-B) together with stolbur related phytoplasmas (16SrXII-A) were identified. This is the first report of detection and identification of a phytoplasma disease of leek in the Czech Republic and Italy. 相似文献
48.
Seven sexually mature boars were studied in two-hour intervals for 8 to 32 hours, as to the variation of testosterone levels in the blood plasma. Blood samples were obtained by means of a cannula inserted in the v. cava cranialis. The hormone level under study showed marked fluctuation. The coefficient of variation of testosterone concentration ranged from 12.7% to 35.2% in the individual animals and for the whole part of the study it was 33.0%. It appeared impossible to derive seriously any regular periodicity of testosterone concentration in boar blood in the 24-hour period from the analysis of the variation of the levels of the hormone in individual animals during the period under study. Further, the study revealed a marked fluctuation of testosterone levels in the blood plasma of twelve sexually mature boars in the course of several days' study. The coefficient of variation of testosterone concentration in individual animals ranged from 18.1% to 106.5%, reaching 77.0% for the whole part of study. The analysis of variance showed statistically significant differences of hormonal levels in individual boars in which the fluctuation of testosterone was studied in the 8- to 32-hour period as well as in several days' period. This proved the role of the animals' individuality in determining the concentration of testosterone in their blood. The discussion concerns the importance of these findings for the evaluation of the role of basal testosterone levels in the blood in classifying the incretion function of the gonads and in the diagnosis of incretion hypogonadism of boars. 相似文献
49.
J. Fránová J. Přibylová M. Šimková M. Navrátil P. Válová 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(8):883-887
Strawflower (Helichrysum bracteatum) with symptoms resembling those associated to phytoplasma infection were observed in several areas in the Czech Republic during the period 1994–2001. Plants with leaf bronzing, reddening and necrosis, proliferation of secondary shoots, flower abnormalities and dwarfing died in advanced stages of the disease. The disease incidence ranged from 2% to 70% and caused significant loss to the flower and seed production. Transmission electron microscopy showed phytoplasmas in sieve cells of affected plants, but not in healthy ones. Association of phytoplasmas with the disease was confirmed by polymerase chain reaction using phytoplasma universal ribosomal primers R16F2n/R16R2. An amplification product of the expected size (1.2 kb) was observed in all samples of the symptomatic strawflowers. The restriction profiles obtained following separate digestion with three endonucleases (AluI, HhaI, MseI) showed that phytoplasmas infecting strawflowers from different localities in the Czech Republic were uniform and undistinguishable from aster yellows (subgroup 16SrI-B). Sequence analysis of 1771 bp of the ribosomal operon amplified with primers P1/U3, R16F2n/R2 and 16R758/P7 indicated that the closest related phytoplasmas were those associated with 'Rehmannia glutinosa var. purpurea', both originating from Bohemia. This is the first report on the occurrence of a phytoplasma-associated disease of strawflower in the Czech Republic. 相似文献
50.
Avian pathogenic Escherichia coli (APEC) are often found in poultry and are responsible for a set of diseases, commonly referred to as avian colibacillosis. One of the important virulence factors is adhesion to different epithelial surfaces, which is mediated by pili. P pili are thought to play a role by means of their PapG adhesin, which occurs in three molecular variants: PapGI, PapGII and PapGIII. This study is the first to determine and analyse the distribution of the different papG alleles in APEC. Our results show a significant predominance of the papGII allele above all other alleles or allele combinations. No statistically significant associations could be found between papG allele distribution and the type of bird, organ of isolation and O serogroup. Finally, the papGII and papGIII sequences showed high homology with mammalian (including human) source papG sequences. 相似文献