Comparison of computed tomography and chest radiography in the detection of rib fractures in abused infants

PURPOSE: Chest radiographs (CXR) are the standard method for evaluating rib fractures in abused infants. Computed tomography (CT) is a sensitive method to detect rib fractures. The purpose of this study was to compare CT and CXR in the evaluation of rib fractures in abused infants. METHODS: This retrospective study included all 12 abused infants identified from 1999 to 2004 who had rib fractures and both CXR and CT (8 abdomen CTs, 4 chest CTs). CT exams had been performed for clinical indications, and were obtained within one day of the CXR. Studies were reviewed by two pediatric radiologists to determine the number, locations, and approximate ages of the rib fractures. A total of 225 ribs were completely (192) or partially (33) seen by CT, and the matched ribs on CXR were used for the analysis. RESULTS: The mean patient age was 2.5 months (1.2-5.6), with seven females and five males. While 131 fractures were visualized by CT, only 79 were seen by CXR (p<.001). One patient had fractures only seen by CT. There were significantly (p<.05) more early subacute (24 vs. 4), subacute (47 vs. 26), and old fractures (4 vs. 0) seen by CT than by CXR. Anterior (42 vs. 11), anterolateral (21 vs. 12), posterolateral (9 vs. 3) and posterior (39 vs. 24) fractures were better seen by CT than by CXR (p<.01). Bilateral fractures were detected more often by CT (11) than by CXR (6). CONCLUSIONS: While this study group is small, these findings suggest that CT is better than CXR in visualizing rib fractures in abused infants.     

中国国防白皮书英译之due+N搭配研究

以英国国家语料库(BNC)和美国当代英语语料库(COCA)为参照语料库,对中国国防白皮书英译本中due+N结构的搭配研究发现,这一结构在英译本中呈现显著搭配、非显著搭配与异常搭配三种情况。due+N结构的非显著搭配与异常搭配很可能受到汉英词典中相关词条的影响。借助语料库手段,在目标语语料库中对节点词进行搭配检索可以帮助避免译文中非显著搭配与异常搭配的出现。     

Time and response matching with topographically different responses

Four pigeons were exposed to several nonindependent concurrent variable-interval schedules of reinforcement. One schedule component required a keypecking response; the other component required a treadlepressing response. The birds matched the ratio of their behavior (as measured by responses and time) between the two topographically different responses to the ratio of reinforcement in those two components. When additional foods not contingent on a keypeck or treadle-press were then added, the birds matched time spent in the components to total rates of food delivered in those components; response matching was somewhat disrupted. The matching law, developed under concurrent variable-interval schedules requiring similar responses, can thus account for choice behavior involving topographically different responses.