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561.
562.
Jacques Hille Matthijs Dekker Hans Oude Luttighuis Ab van Kammen Pim Zabel 《Molecular & general genetics : MGG》1986,205(3):411-416
Summary To test whether virulence mutants of Agrobacterium tumefaciens are capable of promoting T-DNA transfer into plant cells, a tandem array of Cauliflower Mosaic Virus (CaMV) DNA was cloned between T-region border sequences on a wide host range plasmid and introduced into various virulence mutants. The resulting strains were used to infect Brassica rapa cv. Just Right. This assay, recently referred to as agroinfection, is based on the appearance of viral symptoms following transfer of T-DNA to plant cells, and is shown to be at least 100 times more sensitive in detecting T-DNA transfer than tumour formation. Mutants in the loci vir A, B and G, which were avirulent on turnip, failed to induce virus symptoms. Of the two vir D mutants tested, neither induced tumours, but one was capable of inducing virus symptoms. Mutants in vir E, C and F, which induced respectively no, small and normal tumours on turnip, all induced virus symptoms. 相似文献
563.
The material of Eomyidae from three localities (Morteral 1, Morteral 20A and Morteral 22) of the Morteral section in the Magro Basin, eastern Spain, is described. These localities contain remains of Ligerimys and Eomyops. Morteral 1 is situated in the lowest part of the section and contains Ligerimys ellipticus, whereas Morteral 20A and Morteral 22 are situated in the middle part of the section and contain, among other rodent species, Eomyops noeliae. The youngest localities in the Morteral section (Morteral 41 and 44) record Megacricetodon collongensis, first representative of Megacricetodon in the Middle Miocene (MN5). The locality Morteral 20A contains Megacricetodon primitivus; Morteral 1 and Morteral 22 contain a form of Megacricetodon different from both M. primitivus and M. collongensis, therefore, these three localities are of lower Aragonian age (MN4). In the Aragonian type area, L. ellipticus is rare in zone B (lower part of MN4) and frequent in zone C (upper part of MN4). The first record of Eomyops in the Aragonian type area occurs in MN7/8 and in MN5 in Central Europe. The turnover of eomyid faunas in MN4 localities of the Morteral section clearly confirms the hypothesis of Engesser (1999) that Eomyops may have appeared earlier than supposed so far (MN5). 相似文献
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565.
Luimstra Veerle M. Schuurmans J. Merijn de Carvalho Carolina F. M. Matthijs Hans C. P. Hellingwerf Klaas J. Huisman Jef 《Photosynthesis research》2019,141(3):291-301
Photosynthesis Research - The ubiquitous chlorophyll a (Chl a) pigment absorbs both blue and red light. Yet, in contrast to green algae and higher plants, most cyanobacteria have much lower... 相似文献
566.
Matthijs Freudenthal Lars W. van den Hoek Ostende Elvira Martín-Suárez 《Geobios》2013,46(1-2):105-109
The time and mode of colonization of Gargano have been a subject of debate. Taking into account the temporal distribution of the ancestors of the Mikrotia fauna, a Late Tortonian age represents the best fit for the time of migration. How these animals reached the island is even harder to decide. In the past some scholars embraced rafting as an important mechanism enabling small mammals to reach the islands, whereas others rejected this hypothesis, considering it an improbable mode of colonization. The recent record of oceanic rafts indicates that rafting is indeed a very plausible method for small-sized animals to reach islands, and the most probable method for the colonization of Gargano. A polyphasic model, as proposed by Masini and colleagues, is rejected in the case of Gargano, as it is based on a misinterpretation of the adaptive radiations within the Mikrotia fauna. 相似文献
567.