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PURPOSE: To retrospectively evaluate data from the 2003 American College of Radiology (ACR) survey of diagnostic radiologists with regard to characteristics of women radiologists, their professional activities, and the practices in which they work. MATERIALS AND METHODS: The authors analyzed nonindividually identified data from the ACR's 2003 Survey of Radiologists, a stratified random sample survey that guaranteed respondents confidentiality. A cover letter assured respondents that no individually identifiable information would be disseminated; to further enhance confidentiality, survey operations were conducted by a contractor rather than by the ACR itself. There was a 63% response rate, with a total of 1924 responses. Responses were weighted to make them representative of all radiologists in the United States. Two-tailed z tests of percentages and means and multiple regression analysis were used to compare information for women radiologists with that for men radiologists. RESULTS: Twenty-four percent of radiologists in training (residents and fellows) and 18% of posttraining, professionally active radiologists were women. Forty-one percent of posttraining, professionally active women were younger than 45 years in comparison with 29% of men (P = .004). Women radiologists were more likely to have fellowship training than men (69% vs 60%, P = .007), although they were less likely than men to have a subspecialty certificate (16% vs 27%, P < .001). Thirty-nine percent of women and 16% of men worked part-time (P < .001). Women were more concentrated in academia (22% vs 14%, P = .009) and breast imaging (27% vs 6%, P < .001) than their male peers but were underrepresented in interventional radiology (2% vs 13%, P < .001) and neuroradiology (3% vs 10%, P < .001). In situations where radiologists are likely to be practice owners, fewer women than men were owners (75% vs 91%) (P = .011). Women reported the same level of enjoyment of radiology as did men. CONCLUSION: Women radiologists differ from men in regard to age, fellowship training, full- versus part-time employment, academic versus nonacademic practice, subspecialty practice, and practice ownership. 相似文献
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A novel chemokine receptor for SDF-1 and I-TAC involved in cell survival, cell adhesion, and tumor development 总被引:34,自引:0,他引:34 下载免费PDF全文
Burns JM Summers BC Wang Y Melikian A Berahovich R Miao Z Penfold ME Sunshine MJ Littman DR Kuo CJ Wei K McMaster BE Wright K Howard MC Schall TJ 《The Journal of experimental medicine》2006,203(9):2201-2213
The chemokine stromal cell-derived factor (SDF-1; also known as chemokine ligand 12 [CXCL12]) regulates many essential biological processes, including cardiac and neuronal development, stem cell motility, neovascularization, angiogenesis, apoptosis, and tumorigenesis. It is generally believed that SDF-1 mediates these many disparate processes via a single cell surface receptor known as chemokine receptor 4 (CXCR4). This paper characterizes an alternate receptor, CXCR7, which binds with high affinity to SDF-1 and to a second chemokine, interferon-inducible T cell alpha chemoattractant (I-TAC; also known as CXCL11). Membrane-associated CXCR7 is expressed on many tumor cell lines, on activated endothelial cells, and on fetal liver cells, but on few other cell types. Unlike many other chemokine receptors, ligand activation of CXCR7 does not cause Ca2+ mobilization or cell migration. However, expression of CXCR7 provides cells with a growth and survival advantage and increased adhesion properties. Consistent with a role for CXCR7 in cell survival and adhesion, a specific, high affinity small molecule antagonist to CXCR7 impedes in vivo tumor growth in animal models, validating this new receptor as a target for development of novel cancer therapeutics. 相似文献