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31.
Zoosporic true fungi are thought to be ubiquitous in many ecosystems, especially in cool, moist soils and freshwater habitats which are rich in organic matter. However, some of the habitats where these fungi are found may periodically experience extreme conditions, such as soils in extremely dry, hot and cold climates, acidic and alkaline soils, polluted rivers, anaerobic soil and water, saline soil and water, periglacial soils, oligotrophic soils, tree canopies and hydrothermal vents. It is clear that many ecotypes of zoosporic true fungi have indeed adapted to extreme or stressful environmental conditions. This conclusion is supported by studies in both the field and in the laboratory. Therefore, in our opinion, at least some true zoosporic fungi can be considered to be extremophiles.  相似文献   
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Frank G. Nordlie 《Hydrobiologia》2000,434(1-3):165-182
A wide variety of teleost fishes occur in tidal marshes of Atlantic and Gulf coasts of Florida, few of which breed in these habitats or remain there for extended periods of time. A significant fraction of teleosts that do so are members of one of five families. Eleven representative species belonging to these families, whose reproduction and development are considered here, include: Adinia xenica, Fundulus confluentus, F. grandis and F. similis (Fundulidae); Cyprinodon variegatus, Floridichthys carpio and Jordanella floridae (Cyprinodontidae); Gambusia holbrooki and Poecilia latipinna (Poeciliidae); Mugil cephalus (Mugilidae); and Dormitator maculatus (Eleotridae). Spawning or birth locations, patterns of growth and development, times of use of the salt marsh as a nursery area, and development of salinity tolerances/osmotic regulatory capabilities were evaluated for each, considering these in the context of variability of environmental conditions, especially of salinity. Five different patterns of reproduction are shown by these 11 species, and only A. xenica appears to be limited to reproducing in the salt marsh environment. Some of these species are capable of reproducing throughout the year. Several of the species are annuals, most others live only 2 or 3 years. Eight species (those other than M. cephalus, A. xenica and G. holbrooki) were found to show no size relationship, large juvenile to adult sizes, in osmotic regulatory capabilities.  相似文献   
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Homozygous typing cells (HTC) were primed, using responding and stimulating lymphocytes of the same HLA-D groups. These intra-HLA-D group primings showed strong specific responses. Restimulation by HLA-D heterozygous and homozygous cell panels showed no correlation between the restimulating determinant and HLA-D. On the other hand, an unrelated individual, not carrying Dw4 and primed to Dw4 HTC, is restimulated by three of four Dw4-HTC. Thus, one non-HLA-D-associated restimulating determinant and another HLA-D-associated determinant could be identified. The differences among the four Dw4 HTC recognized in secondary MLC could reflect either recognition of separate gene products or recognition of separate determinants on the same gene product.  相似文献   
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