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991.
992.
Geographic patterns and time trends for breast cancer suggest there are preventable causes that may include environmental factors. This article describes the development of new methods used in the Cape Cod Breast Cancer and Environment Study to investigate whether synthetic chemicals in the environment contribute to breast cancer risk.  相似文献   
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Abstract The purpose of the study was to validate an instrument that measures health counseling practices of occupational health nurses. The measure, the health habits counseling questionnaire (HHCQ), was derived from a model of physician counseling practices. The health habits included smoking, alcohol, weight management, and exercise. Safety at work was added for this random sample of California occupational health nurses. Reliability was comparable to original findings for a random sample of physicians drawn from the roster of a western medical society. The validity of the hypothesized global constructs of aggressiveness and indications was not supported. Physicians in the normative sample were more likely to use primary prevention as an indication for counseling. Overall, occupational health nurses and medical society physician members were similar on many aspects of their counseling, although some significant differences did exist.  相似文献   
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Computed tomography was used to evaluate mediastinal lymph nodes in 97 patients with nonsmall cell lung cancer. All patients had thorough surgical-pathological determination of mediastinal node status. Twenty-three patients were found to have metastatic lymph nodes. The usual lymphatic pathways of tumor spread into the mediastinum were defined using the node mapping scheme suggested by the American Thoracic Society. We considered mediastinal nodes abnormal when the short axis of the largest mediastinal node in the lymphatic drainage territory of the cancer was greater than or equal to 10 mm and the difference between this node and the largest node in the other territories is greater than 5 mm. The sensitivity was 78%, the specificity 99%, the positive predictive value 95%, the negative predictive value 94%, and the accuracy 94%. Comparing our method to those that used the size criterion alone, the number of false positives was reduced.  相似文献   
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A retrospective study on the value of magnetic resonance imaging (MRI) in replacing contrast studies of the lumbar spine has been undertaken. Studying pre- and postoperative conditions, the authors attempted to answer the question, Will MRI replace myelography? In this retrospective study, comparison is made in 20 patients between MRI and myelography and with 12 intra-operative findings. The overall impression was that MRI is equally sensitive as the invasive myelogram in diagnosing both protruded lumbar discs and postoperative fibrosis. The practical conclusion was an almost complete abandonment of myelography.  相似文献   
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