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Biological indicators of cadmium exposure and toxicity 总被引:1,自引:0,他引:1
The increasing environmental and occupational exposure of populations to cadmium creates the need for biological indicators of cadmium exposure and toxicity. The advantages and disadvantages of monitoring blood cadmium, urinary, fecal, hair, and tissue cadmium, serum creatinine, beta 2-microglobulin, alpha 1-antitrypsin and other proteins, and urinary amino acids, enzymes, total proteins, glucose, beta 2-microglobulin, retinol-binding protein, lysozyme, and metallothionein are discussed. It is concluded that urinary cadmium, metallothionein and beta 2-microglobulin may be used together to assess cadmium exposure and toxicity. 相似文献
133.
Results from various experiments suggest that the cell surface has an important role in development. However, there is relatively little information on the specific surface molecules involved in developmental processes. In an effort to characterize cell-surface components that may be involved in Drosophila development, we have been making monoclonal antibodies against D. melanogaster imaginal disks. The holometabolous insects are unusual in that scattered among the larval tissues are groups of undifferentiated imaginal cells which, during metamorphosis, will form most of the adult insect. The imaginal disks, which we use as an immunogen, are hollow sacs of cells; each disk will form a specific part of the adult cuticle. Other imaginal cells are found as nests or rings in various larval organs. We describe here results indicating that one of the clones we have isolated, DA.1B6, makes an antibody against an antigen which, in larvae, is generally restricted to the undifferentiated sheets of imaginal epithelial cells. This and other results indicate that the antigen is specific for the diploid epithelia in Drosophila. 相似文献
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Ethylene as a cause of soil fungistasis 总被引:2,自引:0,他引:2
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ELAM-1 is an adhesion molecule for skin-homing T cells. 总被引:96,自引:0,他引:96
Endothelial cell leukocyte adhesion molecule-1 (ELAM-1) has been described as an inducible endothelial cell-adhesion molecule for neutrophils, and is believed to have a key role in the extravasation of these cells at sites of acute inflammation. Here we report that ELAM-1-transfected COS cells also bind a unique skin-associated subset of circulating memory T cells defined by the expression of the cutaneous lymphocyte-associated antigen. T cells expressing this antigen bind at least as well as neutrophils to expressed ELAM-1, whereas other lymphocytes in the peripheral blood bind poorly, or not at all. Immunohistological survey of chronically inflamed tissue specimens revealed that vascular expression of ELAM-1 occurs at cutaneous sites in preference to noncutaneous sites. We conclude that at sites of chronic inflammation, ELAM-1 may function as a skin vascular addressin, a tissue-selective endothelial cell-adhesion molecule for skin-homing memory T lymphocytes. 相似文献
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