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Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
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Defecography in multiple sclerosis patients with severe constipation   总被引:3,自引:0,他引:3  
Gill  KP; Chia  YW; Henry  MM; Shorvon  PJ 《Radiology》1994,191(2):553
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Ninety women were studied in order to compare dose requirements and quality of anaesthesia between target-controlled infusion and two manually controlled infusion schemes for propofol administration: group I received target-controlled infusion for induction (4 μg.ml−1 target blood concentration, increased by 2 μg.ml−1 after 3 min if consciousness not lost), groups II and III received an induction bolus of propofol at infusion rates of 1200 or 600 ml.h−1, respectively, until loss of consciousness. Anaesthesia was maintained with propofol target-controlled infusion in group I or by constant rate infusion in the other two groups. Computer simulations were used to calculate blood and effect-site propofol concentrations. Mean induction times (SD) were 78 (65) s in group I versus 51 (10) s and 62 (12) s in groups II and III, respectively (p < 0.05 between groups II and III). Mean induction doses were: 1.31 (0.44), 2.74 (0.56) and 1.77 (0.43) mg.kg−1 and mean maintenance doses were 13.4 (3.55), 9.32 (1.71) and 9.97 (1.53) mg.kg−1.h−1 in groups I, II and III, respectively (p < 0.05 between all groups). There was a lower incidence of apnoea in group I than in groups II and III. There were no significant differences between the groups in other objective parameters of anaesthetic quality studied. Computer simulations showed an 'overshoot' in propofol blood and effect-site concentration with manual induction and significantly higher maintenance levels with target-controlled infusion.  相似文献   
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Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
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