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91.
Pneumothorax: appearance on lateral chest radiographs 总被引:1,自引:0,他引:1
The appearance of pneumothorax on lateral radiographs obtained with the patient erect were reviewed in 100 patients (122 total examinations). A pneumothorax could be seen on the lateral projection in 89% of the examinations (109 of 122). The displaced pleural line was most frequently identified anteriorly or posteriorly and was less commonly identified at the lung apex or in a subpulmonic location. In 11 cases, an air-fluid level was the only recognizable finding of a pneumothorax on the lateral projection. Although in 27% of examinations (32 of 122) the pneumothorax was either not seen (11%) (n = 13) or was a subtle finding (16%) (n = 19), in 14% of examinations (17 of 122) the lateral projection provided helpful information to supplement the posteroanterior projection. 相似文献
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Paparelli C Cavallaro G Basso L Polistena A Mingazzini PL De Toma G 《Minerva chirurgica》2006,61(6):537-540
Gastrointestinal stromal tumors are rare neoplasms arising from mesenchymal cells of the gastrointestinal tract, that strongly express a class III receptor tyrosine kinase, called KIT, due to some mutations in the KIT proto-oncogene. Two thirds of GISTs are found in the stomach, 20% to 50% in the small bowel (one third in the duodenum), and 5% to 15% in colon and rectum; GISTs, however, may rarely be found also in the oesophagus, omentum, mesentery or the retroperitoneum. Their treatment is strictly surgical, and only R0 resection can achieve good RESULTS: Treatment with Imatinib seems to be promising in case of unresectable or metastatic GIST, even if some trials are studying its effects after curative resection. GIST of the mesocolon are rare, and as in the other locations, require extensive surgery. The Autohrs report a case of giant malignant GIST arising from transverse mesocolon, treated by en-bloc resection of the tumor with a segment of transverse colon and great omentum. 相似文献
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Background
People forget much of what they learn, therefore students could benefit from learning strategies that yield long-lasting knowledge. Yet surprisingly, little is known about how longterm retention is most efficiently mastered. We studied the value of teacher made in class tests as learning aids and compared two types of teacher-made tests (multiple choice and short-answer tests) with a no test (control) to determine their value as aids to retention learning.Method
The study was conducted on two separate batches of medical undergraduate students. This study compared two types of tests [multiple choice questions (MCQs) and short answer questions (SAQs)] with a no test (control) group. The investigation involved initial testing at the end of the lecture (post instruction), followed by an unannounced delayed retention test on the same material three weeks later. The unannounced delayed test comprising of MCQs and SAQs on the same material was given three weeks later to all the three groups.Results
In batch I, the MCQ group had a higher mean delayed retention score of 10.97, followed by the SAQ group (8.42) and the control group (6.71). Analysis of variance (ANOVA) test and least significance difference (LSD) post hoc test revealed statistically significant difference between the means of the three groups. Similar results were obtained for batch IIConclusion
Classroom testing has a positive effect on retention learning; both short-answer and multiple-choice tests being more effective than no test in promoting delayed retention learning, however, multiple-choice tests are better. 相似文献100.