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M. Filek J. Biesaga-Kościelniak I. Marcińska M. Cvikrová I. Macháčková J. Krekule 《Biologia Plantarum》2010,54(3):483-487
The contents of endogenous free and conjugated polyamines, putrescine (Put) and spermidine (Spd), were determined during 9
week of vernalization (at 5 °C) in winter wheat seedlings cultivated on Murashige and Skoog media without (MS0) and with 2
mg dm−3 zearalenone (MSZEN). At the 4th week of chilling treatment, which is sufficient to induce generative development in 30 % of plants, the marked increase in
free and conjugated forms of Put and free Spd were observed. The presence of ZEN in medium significantly accelerated the vernalization.
About 20 % of plants treated with ZEN flowered already after 2 weeks and 40 % after 3 weeks of chilling. Significantly higher
content of free Put was determined in roots grown on MSZEN compared with MS0 during the first 5 weeks of vernalization with
maximum at the 4th week. After germination, a marked decrease in free Spd content was observed both in plants grown on MS0 and MSZEN. Application
of ZEN significantly slowed down the Spd decline in leaves and roots during the first and second week of vernalization. The
content of Spd and its conjugates decreased in vernalized plants after 1 week of cultivation at 20 °C. 相似文献
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Detection of genetic variants affecting cattle behaviour and their impact on milk production: a genome‐wide association study
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Juliane Friedrich Bodo Brand Siriluck Ponsuksili Katharina L. Graunke Jan Langbein Jacqueline Knaust Christa Kühn Manfred Schwerin 《Animal genetics》2016,47(1):12-18
Behaviour traits of cattle have been reported to affect important production traits, such as meat quality and milk performance as well as reproduction and health. Genetic predisposition is, together with environmental stimuli, undoubtedly involved in the development of behaviour phenotypes. Underlying molecular mechanisms affecting behaviour in general and behaviour and productions traits in particular still have to be studied in detail. Therefore, we performed a genome‐wide association study in an F2 Charolais × German Holstein cross‐breed population to identify genetic variants that affect behaviour‐related traits assessed in an open‐field and novel‐object test and analysed their putative impact on milk performance. Of 37 201 tested single nucleotide polymorphism (SNPs), four showed a genome‐wide and 37 a chromosome‐wide significant association with behaviour traits assessed in both tests. Nine of the SNPs that were associated with behaviour traits likewise showed a nominal significant association with milk performance traits. On chromosomes 14 and 29, six SNPs were identified to be associated with exploratory behaviour and inactivity during the novel‐object test as well as with milk yield traits. Least squares means for behaviour and milk performance traits for these SNPs revealed that genotypes associated with higher inactivity and less exploratory behaviour promote higher milk yields. Whether these results are due to molecular mechanisms simultaneously affecting behaviour and milk performance or due to a behaviour predisposition, which causes indirect effects on milk performance by influencing individual reactivity, needs further investigation. 相似文献
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Jan Suchá?ek Petr Sed’a Václav Friedrich Renata Wachowiak-Smolíková Mark P. Wachowiak 《PloS one》2016,11(11)
Media, and particularly TV media, have a great impact on the general public. In recent years, spatial patterns of information and the relevance of intangible geographies have become increasingly important. Gatekeeping plays a critical role in the selection of information that is transformed into media. Therefore, gatekeeping, through national media, also co-forms the generation of mental maps. In this paper, correspondence analysis (a statistical method) combined with cloud lines (a new visual analytics technique) is used to analyze how individual major regional events in one of the post-communist countries, the Czech Republic, penetrate into the media on a national scale. Although national news should minimize distortions about regions, this assumption has not been verified by our research. Impressions presented by the media of selected regions that were markedly influenced by one or several events in those regions demonstrate that gatekeepers, especially news reporters, functioned as a filter by selecting only a few specific, and in many cases, unusual events for dissemination. 相似文献
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C Berche J P Mach J D Lumbroso C Langlais F Aubry F Buchegger S Carrel P Rougier C Parmentier M Tubiana 《BMJ (Clinical research ed.)》1982,285(6353):1447-1451
Transaxial tomoscintigraphy (or single-photon emission computerised tomography) was used to detect secondary deposits of carcinoma in 17 patients who had been injected with iodine-131-labelled monoclonal antibodies against carcinoembryonic antigen. Of 17 tumor sites studied by tomoscintigraphy 16 were detected (sensitivity 94%); five sites had a volume smaller than 10 cm3. Tomoscintigraphy also detected three unknown tumour deposits later confirmed by surgery or radiology. In contrast, when 21 tumour sites in the same patients were studied by rectilinear scintigraphy, only nine tumour sites were detected (sensitivity 43%), of which eight had a volume larger than 50 cm3. 相似文献
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DnaB proteolysis in vivo regulates oligomerization and its localization at oriC in Bacillus subtilis
William H. Grainger Cristina Machón David J. Scott Panos Soultanas 《Nucleic acids research》2010,38(9):2851-2864
Initiation of bacterial DNA replication at oriC is mediated by primosomal proteins that act cooperatively to melt an AT-rich region where the replicative helicase is loaded prior to the assembly of the replication fork. In Bacillus subtilis, the dnaD, dnaB and dnaI genes are essential for initiation of DNA replication. We established that their mRNAs are maintained in fast growing asynchronous cultures. DnaB is truncated at its C-terminus in a growth phase-dependent manner. Proteolysis is confined to cytosolic, not to membrane-associated DnaB, and affects oligomerization. Truncated DnaB is depleted at the oriC relative to the native protein. We propose that DNA-induced oligomerization is essential for its action at oriC and proteolysis regulates its localization at oriC. We show that DnaB has two separate ssDNA-binding sites one located within residues 1–300 and another between residues 365–428, and a dsDNA-binding site within residues 365–428. Tetramerization of DnaB is mediated within residues 1–300, and DNA-dependent oligomerization within residues 365–428. Finally, we show that association of DnaB with the oriC is asymmetric and extensive. It encompasses an area from the middle of dnaA to the end of yaaA that includes the AT-rich region melted during the initiation stage of DNA replication. 相似文献
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Friedrich Rosenkranz 《Plant Systematics and Evolution》1936,85(3):183-212
Ohne Zusammenfassung 相似文献