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991.
992.
The findings on roentgenographic and tomographic examination of the chest were compared in 63 instances of suspected pulmonary metastases. These were further compared with the findings at thoracotomy in 41 instances. Of the 60 patients, 30 had soft tissue or bone sarcomas and 30 had carcinomas arising from colon, ovary or breast, and it also included five with malignant melanoma. Three patients with sarcomas had more than one thoracotomy. The diagnosis of pulmonary metastases by roentgenography of the chest was correct in 60 of 63 instances. Tomograms showed more lesions in 14 of 33 instances of sarcomas and 14 of 30 instances of carcinomas. Thoracotomy revealed even more lesions than were detected by tomography in 21 out of 26 instances with sarcomas and eight of 15 instances of carcinomas. Of the 37 patients with a solitary metastasis detected on roentgenograms of the chest, 22 were found to have additional lesions on the tomograms, 11 of 16 sarcomas and 11 of 21 carcinomas. At thoracotomy, however, nine of ten patients with a single metastasis from sarcomas were found to have even more lesions, while, in patients with carcinomas, tomograms were found to be accurate. Routinely, prior to major ablative operations for sarcomas and before excision of pulmonary metastases, it is suggested that tomography be carried out.  相似文献   
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Aspiration pneumonia is a major cause of morbidity and mortality among the elderly who are hospitalized or in nursing homes. Multiple risk factors for pneumonia have been identified, but no study has effectively compared the relative risk of factors in several different categories, including dysphagia. In this prospective outcomes study, 189 elderly subjects were recruited from the outpatient clinics, inpatient acute care wards, and the nursing home care center at the VA Medical Center in Ann Arbor, Michigan. They were given a variety of assessments to determine oropharyngeal and esophageal swallowing and feeding status, functional status, medical status, and oral/dental status. The subjects were followed for up to 4 years for an outcome of verified aspiration pneumonia. Bivariate analyses identified several factors as significantly associated with pneumonia. Logistic regression analyses then identified the significant predictors of aspiration pneumonia. The best predictors, in one or more groups of subjects, were dependent for feeding, dependent for oral care, number of decayed teeth, tube feeding, more than one medical diagnosis, number of medications, and smoking. The role that each of the significant predictors might play was described in relation to the pathogenesis of aspiration pneumonia. Dysphagia was concluded to be an important risk for aspiration pneumonia, but generally not sufficient to cause pneumonia unless other risk factors are present as well. A dependency upon others for feeding emerged as the dominant risk factor, with an odds ratio of 19.98 in a logistic regression model that excluded tube-fed patients.  相似文献   
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The osmotic fragility of erythrocytes from mice with Ehrlich ascites tumor was compared with that of erythrocytes from normal control animals. Erythrocytes collected from mice 15 days after the ip injection of tumor cells exhibited a uniform pattern of abnormal resistance to hemolysis in hypotonic saline, with 50% hemolysis occurring at an average saline concentration of 0.44% compared to an average of 0.49% for 11 controls a significant difference (P less than 0.0001). Erythrocytes from mice with this tumor apparently undergo an alteration in some component of the cell membrane that regulates either permeability to cations and water or distensibility of the cell.  相似文献   
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