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1.
Dr. Ed. Formánek 《Plant Systematics and Evolution》1888,38(12):419-423
Ohne Zusammenfassung 相似文献
2.
Barbora Straková Michail Rovatsos Lukáš Kubička Lukáš Kratochvíl 《BioEssays : news and reviews in molecular, cellular and developmental biology》2020,42(10):2000050
Frequent independent origins of environmental sex determination (ESD) are assumed within amniotes. However, the phylogenetic distribution of sex-determining modes suggests that ESD is likely very ancient and may be homologous across ESD groups. Sex chromosomes are demonstrated to be old and stable in endothermic (mammals and birds) and many ectothermic (non-avian reptiles) lineages, but they are mostly non-homologous between individual amniote lineages. The phylogenetic pattern may be explained by ancestral ESD with multiple transitions to later evolutionary stable genotypic sex determination. It is pointed out here that amniote ESD shares several key aspects with sequential hermaphroditism of fishes such as a lack of sex differences in genomes, biased population sex ratios, and potentially also molecular mechanism related to general stress responses. Here, it is speculated that ESD evolves via a heterochronic shift of the sensitive period of sex change from the adult to the embryonic stage in a hermaphroditic amniote ancestor. Also see the video abstract here https://youtu.be/q2mjtlCefu4 . 相似文献
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Dr. Ed. Formánek 《Plant Systematics and Evolution》1888,38(6):186-190
Ohne Zusammenfassung 相似文献
5.
Estimating the extent of biological invasions is critical in predicting the effect of exotic species. We investigated the occurrence and number of alien freshwater plants and give information on the composition of alien aquatic flora, their trend in time, invasion pathway, and their invasive character. 相似文献
6.
Dr. Ed. Formánek 《Plant Systematics and Evolution》1884,34(5):157-168
Ohne Zusammenfassung 相似文献
7.
Ed Echeverria 《Physiologia plantarum》1991,81(1):51-54
The sucrose content of acid lime [ Citrus aurantifolia (Christm.) Swing.] juice tissue was measured at time 0 and at various times following incubation at 15.5, 26.6 and 37.7°C. The decline in sucrose content in fruit stored at 15.5°C paralleled the expected values for a sucrose solution at pH 2.1. At higher temperatures, the in vivo sucrose content decreased at significantly lower rates than the expected values. In fruit stored at 26.6 and 37.7°C, the vacuolar pH increased 0.11 and 0.23 units, respectively. When sucrose hydrolysis was recalculated at the increased vacuolar pH of juice cells stored at 26.6 and 37.7°C, the calculated values were similar to the measured values obtained in vivo. It is concluded that within the limits of the experimental conditions, the rates of sucrose acid hydrolysis are regulated by changes in the vacuolar H+ concentration. 相似文献
8.
Auto anti-A1 and auto anti-NA1 after bone marrow transplantation 总被引:1,自引:0,他引:1
P Herzog P Korínková M Stambergová M Lukásová 《Folia haematologica (Leipzig, Germany : 1928)》1987,114(6):874-880
The production of auto anti-A1 and auto anti-NA1 antibodies in patient with aplastic anemia has been described. The patient of group A1 received bone marrow from his brother of group A2. For immunosuppression cyclosporine A was administered. 相似文献
9.
Mutations were induced in Neurospora which cause increased sensitivity to MMS (methyl methane-sulfonate) and other mutagens. Genetic analysis of such mus demonstrated that some of them defined new DNA repair genes (mus-21, and mus-27 to mus-30), while others represented new alleles in previously known genes. To characterize them further, and especially to identify rec- types which have not yet been found in this species, many MMS-sensitive strains were tested for cross-sensitivities to bleomycin (BLM) and to hydrogen peroxide (H2O2) to which some rec- of other species are hypersensitive. In Neurospora, many of the MMS-sensitive mutants were found to be cross-sensitive to BLM and frequently these were also hypersensitive to ionizing radiation. Bleomycin sensitivity was demonstrated for all alleles of 10 different genes, 4 of them new ones, with mus-27 being the most sensitive of the latter (resembling uvs-6; Koga and Schroeder, 1987, Mutation Res., 183, 139). In contrast, very few of the MMS-sensitive mutants were hypersensitive to H2O2 and, in general, results of H2O2 tests were variable and differences between strains small. However, consistent deviations from wild type were observed in a few cases (most clearly for mus-9 and mus-11) when results from treatments of germinating conidia were compared with those of non-growing ones. 相似文献
10.