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81.
Dr. Jaroslav KŘiŽenecký 《Development genes and evolution》1924,101(4):621-665
Ohne Zusammenfassung 相似文献
82.
The present work collects the new names of syntaxa (in the sense of the Code of Phytosociological Nomenclature,Barkman et al. 1986) above subassociation, rank found in the literature received by the Library of the Conservatoire et Jardin botaniques in Geneva. For the year 1992, 658 names have been listed. For each one of them, an appreciation about its validity is given relating to the Code of Phytosociological Nomenclature. Fifteen names are given in addition to the Indexes 1987, 1990 and 1991 (Theurillat & Moravec 1990, 1993, 1994). 相似文献
83.
Havránek Vladimír Kučera Jan Horáková Jitka Voseček Václav Smolík JiŘí Schwarz Jaroslav Sýkorová Ivana 《Biological trace element research》1999,(1):431-442
A comparison of instrumental neutron activation analysis (INAA) and proton-induced X-ray emission (PIXE) results for sizefractionated
atmospheric aerosols (“coarse” and “fine” fractions with an equivalent aerodynamic diameter of 2–10 Μm and < 2 Μm, respectively,
or the PM10 fraction) showed that PIXE yielded significantly lower results for the PM10 and coarse fractions, especially for
elements with a low Z resulting from a particle size effect. Somewhat lower PIXE results were also obtained for the fine fraction
of atmospheric aerosols. A correction is also needed for irregularly shaped deposits of combustion aerosols collected by a
cascade impactor in 11 size fractions ranging from 0.016 to 14.3 Μm, as well as for thick samples of fly and bottom ashes.
An equivalent layer thickness (ELT) model is proposed to correct the matrix effects in PIXE. The approaches for the calculation
of ELT using a comparison of PIXE and INAA results or by comparing PIXE results obtained using two different incident proton
beam energies (1.31 and 2.35 MeV) are described. The correction for the ash pellets and irregular deposits are also discussed. 相似文献
84.
Anthers of diploid genotypes of Solanum tuberosum capable of androgenesis were cultured on different media to examine the effect on induction of pollen embryogenesis of 2,4-d and lactose. Anthers cultured in callogenic medium with 2,4-d and sucrose produced pollen derived embryoids only exceptionally. When sucrose was replaced by lactose the frequency of embryogenesis was as high or higher than in embryogenic auxin-free medium. Substitution of lactose for sucrose in the embryogenic medium had no effect. Supplementing the embryogenic medium with 2,4-d strongly reduced the frequency of pollen embryoids in the presence of sucrose but not with lactose.Abbreviations 2,4-d
2,4-dichlorophenoxyacetic acid 相似文献
85.
Mráz J Dusková S Gálová E Nohová H Krausová P Linhart I Simek P 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,778(1-2):357-365
A sensitive method for determination of the N-methylcarbamoyl adduct at the N-terminal valine of globin, a new metabolic product of the industrial solvent N,N-dimethylformamide (DMF), has been developed and validated. The method includes conversion of the adduct by the Edman degradation to 3-methyl-5-isopropylhydantoin (MVH), which is followed by optimized gas chromatographic analysis with mass spectrometric detection at m/z 114. The recovery of MVH from terminal N-methylcarbamoylvaline was determined using a model dipeptide to be 90%. Calibration of the method is done with MVH, employing 3-methyl-5-isobutylhydantoin as the internal standard. The limit of detection is 0.2 nmol MVH/g globin when a 100-mg sample is used. Within- and between-day precision is 4-10%. The method has been used to determine the background levels of MVH in unexposed subjects. Further, toxicokinetic studies in volunteers laid the grounds for setting the reference value for biological monitoring of occupational exposure to DMF. 相似文献
86.
Seed dispersal is a crucial process for the dynamics and maintenance of plant populations. Free-ranging animals are effective dispersal vectors because they can move between similar habitats and transport seeds into favourable environments. Dung samples from two species of common free-ranging mammals—deer and wild boar—were used to study endozoochorous dispersal of seeds in a military training area in western Bohemia. The area was abandoned after WWII, and the military training area was established in 1953. The vegetation consists of shrublands and dry grasslands. Data on the local species pool of grassland herbs and forbs were collected to compare the characteristics of dispersed versus non-dispersed plants. Deer and wild boar dispersed 84 plant species; however, species composition of seedlings emerging from dung samples showed significant differences between dispersal vectors and notable change across the growing season. 80% of all seedlings extracted from the dung samples belonged to stinging nettle, Urtica dioica. From trait analyses, seeds of endozoochorous plants had a higher longevity index in the soil seed bank than non-endozoochorous plants and more often possessed a mucilaginous surface. Our results show that deer and boar are successful, though not substitutable dispersers. 相似文献
87.
Wasimuddin Josef Bryja Alexis Ribas Stuart J. E. Baird Jaroslav Piálek Joëlle Goüy de Bellocq 《Ecology and evolution》2016,6(9):2688-2701
Host‐parasite interaction studies across hybrid zones often focus on host genetic variation, treating parasites as homogeneous. ‘Intimately’ associated hosts and parasites might be expected to show similar patterns of genetic structure. In the literature, factors such as no intermediate host and no free‐living stage have been proposed as ‘intimacy’ factors likely constraining parasites to closely follow the evolutionary history of their hosts. To test whether the whipworm, Trichuris muris, is intimately associated with its house mouse host, we studied its population genetics across the European house mouse hybrid zone (HMHZ) which has a strong central barrier to gene flow between mouse taxa. T. muris has a direct life cycle and nonmobile free stage: if these traits constrain the parasite to an intimate association with its host we expect a geographic break in the parasite genetic structure across the HMHZ. We genotyped 205 worms from 56 localities across the HMHZ and additionally T. muris collected from sympatric woodmice (Apodemus spp.) and allopatric murine species, using mt‐COX1, ITS1‐5.8S‐ITS2 rDNA and 10 microsatellites. We show four haplogroups of mt‐COX1 and three clear ITS1‐5.8S‐ITS2 clades in the HMHZ suggesting a complex demographic/phylogeographic history. Microsatellites show strong structure between groups of localities. However, no marker type shows a break across the HMHZ. Whipworms from Apodemus in the HMHZ cluster, and share mitochondrial haplotypes, with those from house mice. We conclude Trichuris should not be regarded as an ‘intimate’ parasite of the house mouse: while its life history might suggest intimacy, passage through alternate hosts is sufficiently common to erase signal of genetic structure associated with any particular host taxon. 相似文献
88.
89.
Toxoplasma is parasite of cats that uses any warm-blooded animals as intermediate hosts. It is known to induce shifts in behavior, physiology and even morphology of its intermediate hosts, including humans. The lower second to fourth digit ratio (2D:4D ratio) in infected man and women, and higher height in infected man suggest that sex steroid hormones like testosterone could play a role in these shifts. Here, we searched for another indirect indication for a higher postnatal testosterone level, i.e. increased perceived dominance and masculinity in infected men. We showed portrait pictures of 89 male students of which 18 were Toxoplasma-infected to 109 female students. When we statistically corrected for age, men with latent toxoplasmosis were perceived as more dominant (p=0.009) and masculine (p=0.052). These results support the idea that the higher level of testosterone could be responsible for at least some of the toxoplasmosis-associated shifts in human and animal behavior. 相似文献
90.
Gabriel Minarik Gabriela Repiska Michaela Hyblova Emilia Nagyova Katarina Soltys Jaroslav Budis Frantisek Duris Rastislav Sysak Maria Gerykova Bujalkova Barbora Vlkova-Izrael Orsolya Biro Balint Nagy Tomas Szemes 《PloS one》2015,10(12)