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Normal and diseased isolated lungs: high-resolution CT 总被引:8,自引:0,他引:8
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N. Hayes R. Rollins A. Weinberg O. Brawley C. Baquet J. S. Kaur N. A. Palafox 《Cancer causes & control : CCC》2005,16(1):41-50
During the last two decades extraordinary progress in developing and using effective cancer prevention strategies, early detection interventions, and cancer treatments has been made. This progress has resulted in an overall decline in mortality rates for all cancers combined. Nonetheless, cancer is the second most common cause of death in the United States. Although cancer is a diagnosis that many survive, cancer experiences across populations may vary considerably. These differences in cancer experiences have created an unequal disease burden that presents distinct professional and moral challenges to our nation. Many cancer control plans suggest specific strategies that prioritize eliminating cancer-related disparities. This article describes certain cancer-related disparities in the United Sates and gives several examples of how communities and disenfranchised populations are using comprehensive cancer control (CCC) approaches to eliminate these disparities. One or two interventions are highlighted in each example. 相似文献
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The adhesion of hematopoietic progenitor cells to bone marrow stromal cells is critical to hematopoiesis and involves multiple effector molecules. Stromal cell molecules that participate in this interaction were sought by analyzing the detergent-soluble membrane proteins of GBI/6 stromal cells that could be adsorbed by intact FDCP-1 progenitor cells. A single-chain protein from GBI/6 cells having an apparent molecular weight of 37 Kd was selectively adsorbed by FDCP-1 cells. This protein, designated p37, could be surface-radiolabeled and thus appeared to be exposed on the cell membrane. An apparently identical 37- Kd protein was expressed by three stromal cell lines, by Swiss 3T3 fibroblastic cells, and by FDCP-1 and FDCP-2 progenitor cells. p37 was selectively adsorbed from membrane lysates by a variety of murine hematopoietic cells, including erythrocytes, but not by human erythrocytes. Binding of p37 to cells was calcium-dependent, and was not affected by inhibitors of the hematopoietic homing receptor or the cell-binding or heparin-binding functions of fibronectin. It is proposed that p37 may be a novel adhesive molecule expressed on the surface of a variety of hematopoietic cells that could participate in both homotypic and heterotypic interactions of stromal and progenitor cells. 相似文献
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In December, 1989, the Department of Transportation (DOT) in conjunction with the Federal Aviation Administration (FAA) mandated an extensive urine drug testing program for selected positions within the airline industry. At the end of 1 year we have tested 7,872 applicants under these rules, with a positive finding rate of 0.17%. We have also tested 32,157 applicants, including those applying for DOT-covered positions, with a positive rate of 2.82%. Considering only the two major drugs of abuse--marijuana and cocaine--we found the positive rate to be an order of magnitude greater than the rate discovered under the DOT program. We present these data together with a discussion of some of the possible reasons for this major disparity. We also present findings for barbiturates and benzodiazepines which are not tested under the DOT program, but which have safety implications related to the aviation industry. 相似文献
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