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Margaret E. Elmes MB BS PhD J. Clarkson PhD J. Gwyn Jones PhD 《Environmental geochemistry and health》1983,5(2-3):85-87
The zinc content of intestinal epithelial cells in human jejunum and ileum has been measured using X-ray microanalysis. The range of values was wide, the highest being found in stem cells and enterocytes. Significant differences were found in jejunum from gastric carcinoma patients and ileum from Crohn's disease patients compared with patients with non malignant, non inflammatory disease. 相似文献
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Macroinvertebrate and fish populations in a restored impounded salt marsh 21 years after the reestablishment of tidal flooding 总被引:2,自引:0,他引:2
Swamy V Fell PE Body M Keaney MB Nyaku MK McIlvain EC Keen AL 《Environmental management》2002,29(4):516-530
During the last two decades, the State of Connecticut has restored tidal flow to many impounded salt marshes. One of the first
of these and the one most extensively studied is Impoundment One in the Barn Island Wildlife Management Area in Stonington,
Connecticut. In 1990, twelve years after the re-establishment of tidal flooding, the density of the marsh snail Melampus bidentatus, the numerically dominant macroinvertebrate of the high marsh, in Impoundment One was about half that in reference marshes
below the breached impoundment dike. By 1999 the densities of Melampus above and below the dike were not significantly different, but the shell-free biomass was greater above the dike as a result
of the somewhat larger number and size of the snails there. Twenty-one years after the renewal of tidal flooding, three marsh
macroinvertebrates (the amphipods Orchestia grillus and Uhlorchestia spartinophila and the mussel Geukensia demissa) were significantly less abundant in the previously impounded marsh than in the reference marshes, whereas another amphipod
(Gammarus palustris) was more abundant above the breached dike where conditions appeared to be somewhat wetter. In 1991 the fish assemblage in
a mosquito-control ditch in Impoundment One was similar to that in a ditch below the breached dike; however, the common mummichog
Fundulus heteroclitus appeared to be less abundant in the restoring marsh. By 1999 the number of mummichogs caught in ditches was significantly
greater in Impoundment One than in the reference marsh, but the numbers of mummichogs trapped along the tidal creek were comparable
above and below the dike. The results obtained in this study and those of other restoring marshes at Barn Island indicate
the full recovery of certain animal populations following the reintroduction of tidal flow to impounded marshes may require
up to two or more decades. Furthermore, not only do different species recover at different rates on a single marsh, but the
time required for the recovery of a particular species may vary widely from marsh to marsh, often independently of other species. 相似文献
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