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991.
992.
In a series of 154 patients (116 male and 38 female) with so called pulmonary hamartoma the peak incidence was in the sixth decade, with only three patients less than 20 years of age. Sequential radiographs showed that in 55 patients the tumour first appeared in adult life and that in 53 it progressively increased in size. The age incidence and progressive growth leads to the conclusion that the tumour is a benign neoplasm rather than a hamartoma, consisting of various connective tissues intersected by clefts lined by respiratory epithelium. The epithelial elements are regarded as entrapped non-neoplastic inclusions and the tumour as a purely mesenchymal neoplasm: the name mesenchymoma therefore seems the most appropriate. There were two recurrences after simple enucleation, 10 and 12 years later. A total of 142 tumours were parenchymal, and only 12 were endobronchial. All lobes were affected but there was a slight preponderance in the left upper lobe. Four patients had two (synchronous) mesenchymomas. There was an associated bronchial carcinoma in 11 patients, synchronous in six and metachronous in five.  相似文献   
993.
Goodman  LR; Troup  PJ; Thorsen  MK; Youker  JE 《Radiology》1985,155(3):571-573
The automatic implantable cardioverter-defibrillator is used in patients with ventricular tachyarrhythmias resistant to medical or surgical therapy. The device, which has a unique radiographic appearance, senses ventricular tachycardia or fibrillation and automatically delivers a cardioverting or/defibrillating electric shock.  相似文献   
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BACKGROUND: Complaints possibly caused by arrhythmias are frequently seen in general practice. It is unclear to what extent such complaints can differentiate between arrhythmias and other pathology in general practice. OBJECTIVES: We aimed to assess the value of symptoms (a) in diagnosing arrhythmias in general practice and (b) in identifying patients with clinically relevant arrhythmias. METHOD: During a 2-year period, a structured history from 762 patients with new complaints possibly related to an arrhythmia was taken by the GP, and a transtelephonic electrocardiogram (ECG) was made. RESULTS: In 28.3% of the patients, arrhythmias were detected and 8.8% were clinically relevant. Several patient characteristics, symptoms and medical history findings have high predictive values in diagnosing arrhythmias. In the logistic regression analysis, age and, to a lesser extent, male gender, palpitations and dyspnoea during consultation and the use of cardiovascular drugs are associated with the presence of arrhythmias. In detecting clinically relevant arrhythmias the same parameters apart from gender are important, as well as a history of arrhythmias. The use of central nervous system medication and frequent psychosomatic complaints are negatively associated with the presence of clinically relevant arrhythmias. CONCLUSIONS: In general practice, patient characteristics, symptoms and medical history findings can be used in the detection of arrhythmias and the assessment of their severity. They can help in the decision of whether to make an ECG recording.   相似文献   
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Summary— The azole antimycotic itraconazole is a potent and relatively unspecific inhibitor of cytochrome P450 enzymes and has a potentially dangerous interaction with midazolam and triazolam. The possible interaction between itraconazole and diazepam was investigated in a double-blind, randomized, cross-over study. Ten healthy volunteers were given orally placebo or itraconazole 200 mg a day for 4 days. The challenge dose of 5 mg of diazepam was ingested on the fourth day, after which plasma samples were collected and psychomotor performance tests were carried out for 42 h. Despite a statistically significant small increase in the area under the plasma diazepam concentration-time curve and the elimination half-life of diazepam, there was no clinically significant interaction as determined by the psychomotor performance tests. The lack of significant first-pass metabolism and the different metabolic pathways of diazepam explain the smaller interaction potential of diazepam compared with midazolam and triazolam. Diazepam, unlike midazolam and triazolam, can be prescribed in usual doses for patients receiving itraconazole and probably other inhibitors of P4503A4, at least when diazepam is used as single doses.  相似文献   
999.
Kastan  DJ; Ackerman  LV; Feczko  PJ 《Radiology》1987,162(3):853-856
Five radiographs of double-contrast colon examinations demonstrating subtle mucosal changes of inflammatory bowel disease and five radiographs of healthy colonic mucosa were selected and digitized to four levels of resolution. Pixel sizes of 0.1 mm, 0.2 mm, 0.4 mm, and 0.8 mm were used. Ten radiologists interpreted the images, which were displayed on laser-printed film. Analysis of variance with repeated measures was performed and receiver operator characteristic curves were determined. The results demonstrate that the sensitivity in detecting subtle mucosal abnormalities improved as the resolution improved, with the best sensitivity at the highest resolution; more experienced readers detected details well even at the poorer levels of resolution; the resolution necessary for successfully evaluating the colonic mucosa was lower than expected; and given low noise levels, the matrix size used in conventional television fluoroscopy would be adequate for mucosal evaluation.  相似文献   
1000.
The authors examined 19 patients with diffuse histiocytic lymphoma of the brain, including 8 with primary disease and 11 with secondary disease. Both primary disease and secondary disease involving the brainstem and deep nuclei exhibited the characteristic CT appearance, consisting of a large, solid, homogeneously enhanced mass with varying amounts of edema. However, most secondary lymphomas outside the brainstem and basal ganglia contained large areas of low attenuation consistent with necrosis. Multifocal lesions were seen only in patients with secondary lymphoma. Systemic chemotherapy for extracranial lymphoma had no effect on the CT appearance of intracranial lesions. The authors suggest that these "unusual" CT patterns are actually typical of a distinct subset of histiocytic lymphomas.  相似文献   
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