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Berthold Heinze 《Plant methods》2007,3(1):4-7
Background
Chloroplast genomes evolve slowly and many primers for PCR amplification and analysis of chloroplast sequences can be used across a wide array of genera. In some cases 'universal' primers have been designed for the purpose of working across species boundaries. However, the essential information on these primer sequences is scattered throughout the literature. 相似文献4.
Cattaneo A Yngve A Koletzko B Guzman LR;Promotion of Breastfeeding in Europe project 《Public health nutrition》2005,8(1):39-46
OBJECTIVE: To describe the current situation regarding protection, promotion and support of breast-feeding in Europe, as a first step towards the development of a blueprint for action. DESIGN AND SETTING: A questionnaire was completed by 29 key informants and 128 other informants in the EU, including member states, accession and candidate countries. RESULTS: EU countries do not fully comply with the policies and recommendations of the Global Strategy on Infant and Young Child Feeding that they endorsed during the 55th World Health Assembly in 2002. Some countries do not even comply with the targets of the Innocenti Declaration (1990). Pre-service training on breast-feeding practice is inadequate and in-service training achieves only low to medium coverage. The Baby Friendly Hospital Initiative is well developed only in three countries; in 19 countries, less than 15% of births occur in baby-friendly hospitals. The International Code of Marketing of Breastmilk Substitutes, endorsed in 1981 by all countries, is not fully applied and submitted to independent monitoring. The legislation for working mothers meets on average the International Labour Organization standards, but covers only women with full formal employment. Voluntary mother-to-mother support groups and trained peer counsellors are present in 27 and 13 countries, respectively. Breast-feeding rates span over a wide range; comparisons are difficult due to use of non-standard methods. The rate of exclusive breast-feeding at 6 months is low everywhere, even in countries with high initiation rates. CONCLUSIONS: EU countries need to revise their policies and practices to meet the principles inscribed in the Global Strategy on Infant and Young Child Feeding in order to better protect, promote and support breast-feeding. 相似文献
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The abundance of active soil ciliates was determined by Singh's dilution culture method any by the direct counting method of Lüftenegger et al. (1988) in 13 samples of 3 types of soil (meadow topsoil, spruce and beech litter). This comparative investigation revealed that the dilution culture methods are likely to overestimate active ciliates by orders of magnitude (with an average factor of 2000). One of the disadvantages of dilution methods is their difficulty meeting the assumptions of the MPN (most probable number) estimation model, on which they are based. A further serious problem is the proper separation of encysted and active cells. Due to a wide range of systematic errors, MPN estimates become seriously biased. But even if the basic assumptions could be met, the maximal precision of the estimate is far too low for a useful application within the context of soil ecology. This was revealed by the calculation of approximate confidence limits. Subjecting the data to analysis of variance showed that the direct counts can clearly differentiate ciliate abundances in forest litter versus meadow soil, whereas the dilution culture method is not precise enough to achieve this distinction. The MPN estimates did not even correlate significantly with the direct counts. Our investigation thus proved that dilution culture methods are beset with methodological deficiencies, resulting in unreliable estimates of protozoan abundances in soil. 相似文献
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E Berthold M Heller H Pfützner R Leirer K Sachse 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(5):353-361
Monoclonal antibodies (mabs) against Mycoplasma (M.) bovis were prepared for use in diagnosis of bovine mastitis. From the original 32 hybridomas actively secreting mabs against M. bovis, 6 stable lines were cloned. Two of them, Mb 5D8 and Mb 4F6, recognized M. bovis antigens of estimated molecular weights of 33 and 26 kDa, respectively. They showed no cross-reaction to other bovine mycoplasmas, thus rendering them useful for specific detection of this pathogen. All mabs investigated cross-reacted with M. agalactiae which is known to be closely related to M. bovis, but does not occur in cattle. Two other mabs, Mb 5D4 and Mb 1F6, exhibited further cross-reactions to a number of bovine mycoplasma species. Finally, mabs Mb 5D5 and Mb 2G5 reacted with all mycoplasmas tested. The possibility that they recognized constituents of the broth culture medium is discussed. 相似文献
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Barbara Fussi Joseph Bonello Eman Calleja Berthold Heinze 《European Journal of Forest Research》2012,131(2):347-354
The nativity of Populus alba in the Mediterranean has only been confirmed in the last decade, following the discovery of 8,000-year-old leaf imprints
in Southern France. Recent evidence has even emerged from molecular studies suggesting that the species is native to some
of the islands, and these populations may be relicts of a native flora that arrived there much earlier than previously thought.
In view of this, samples obtained from the Central Mediterranean archipelago of Malta and other neighbouring regions were
analysed to determine the native status of the Maltese populations and possibly trace their origins. All 38 samples were investigated
in order to assess the genetic diversity and origin of Maltese trees. Nuclear microsatellite analysis revealed that all 28
trees sampled from the two islands of Malta belonged to one clone. Chloroplast data suggested relatedness of the Maltese clone
to Italian P. alba samples. However, nuclear data suggested additional admixture through pollen from North Africa. Existing archival and palaeontological
records were also examined for any supporting evidence. On considering the latter records in combination with molecular evidence,
we arrived to the conclusion that arrival of this clone in Malta through human introduction in the sixteenth century is the
most likely explanation, since alternative scenarios like autovegetative propagation or arrival by seed seem highly unlikely. 相似文献
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