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Gallium-67 citrate scanning was prospectively evaluated in 55 patients who had lung lesions suspected to be primary carcinoma on chest x-ray films and in whom subsequent histologic diagnosis was obtained. Of 47 patients with histologically proved carcinoma of the lung, 44 (94 per cent) had a positive 67Ga scan. No patient with a positive scan had a benign lesion, so that the positive scan accuracy rate was 100 per cent. All 8 patients with a benign lesion and 3 patients with a malignant lesion had negative scans, for a negative scan accurary rate of 72 per cent for benign lesions. These results give statistical validity for the usefulness of the 67Ga scan in diagnosing carcinoma of the lung (p less than 0.001). Tumor cell type had little effect on the sensitivity of 67Ga scan. The 67Ga scan was equally useful in the evaluation of peripheral and central lesions. There was little difference amount T1, T2, and T3 classified lesions in their ability to take up 67Ga. The 67Ga scan was competitive with mediastinoscopy in assessing mediastinal lymph node metastases and provides a noninvasive method of assessing hilar lymph node metastases. There was a good correlation between the clinical staging of patients with lung cancer based on a chest x-ray film and 67Ga scanning and the staging after surgical treatment based on the histology of the resected specimens.  相似文献   
94.
Forty-eight knees were evaluated after proximal tibial osteotomy, performed for varus deformity to determine the desired amount of correction of the deformity, the effect of osteotomy on knee motion during gait and one medial-plateau force during standing, and the relationships between these factors and the result. Correction of the tibiofemoral angle to 5 degrees of genu valgum or more produced the best and most lasting results. Stance-phase flexion-extension increased the rotation decreased in knees with good results while the other gait parameters were not significantly changed. Medial-plateau force was decreased by successful tibial osteotomy. The knees with the best and most lasting results had 7 degrees of stance-phase flexion-extension or more during walking and either a valgus tibiofemoral angle of 5 degrees or more or a medial-plateau force of 50 per cent of body weight or less.  相似文献   
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The possible correlations between unipolar endocardial electrogram amplitudes and voltage threshold stimulation were tested with electrodes having metallic tips of two different areas. The threshold measurements were always studied with the same pulse characteristics. The data were analyzed through five mathematical functions (linear, exponential, potential, hyperbola and translate hyperbola). The results show a significant correlation, mainly by hyperbolic and exponential functions. Consequently, we could deduce a parameter value since we already knew the other one. This was possible not only during the first implantation, but also later on.  相似文献   
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In ten patients breast reconstruction was done after surgical treatment for a premalignant or malignant breast disease. In six of these, prophylactic subcutaneous mastectomy and implant reconstruction were carried out, and in the remaining four reconstruction was done after simple or modified radical mastectomy. It is suggested that these procedures should be considered by those physicians and surgeons who undertake evaluation and treatment of breast disease in women. Breast reconstruction should be considered and offered to patients who suffer from the severe personal and emotional trauma attendant to surgical operation for breast disease.  相似文献   
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The esophageal airway has gained increasing acceptance in airway management during cardiopulmonary resuscitation, and its enthusiastic advocates are urging expansion of its use. A fatal case of esophageal perforation following the use of an esophageal airway is presented. Possible contributing factors are discussed. A modified esophageal airway which seems safer and more versatile, effective, and economic is described.  相似文献   
100.
Patterns of ambulatory health care in five different delivery systems   总被引:2,自引:0,他引:2  
Few empirical investigations permit systematic comparison of the impact of widely-varying delivery systems within a single population sample. This study provides such a comparison, describing patterns of ambulatory care among patients using five different systems in Washington, D.C. as a regular source of health care: solo practice, fee-for-service group practice, prepaid group practice, public clinics, and hospital outpatient departments or emergency rooms. Comparisons are adjusted statistically to account for major patient group variations, and the results reveal substantial differences among the five systems. Sources used primarily by the poor--hospital outpatient departments, emergency rooms, and public clinics--contained important structural and financial barriers, and had the lowest rates of patient-initiated use. The prepaid system, in contrast, maximized patient's access to both preventive care and symptomatic care, and did not seem to inhibit physician-controlled follow-up care. The results suggest some perverse effects of fee-for-service payment: patients, especially poor patients, appeared to be deterred from seeking preventive and symptomatic care, while physicians were encouraged to expand follow-up services. Moreover, services in fee-for-service systems were distributed less equitably relative to both income and medical need than in the prepaid system. These findings have direct implications for policy decisions concerning organizational and financial arrangements for the delivery of ambulatory care.  相似文献   
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