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91.
Magnetic resonance (MR) imaging and computed tomography (CT) were compared in a prospective study of 48 patients for the detection of metastatic mediastinal lymphadenopathy from bronchogenic carcinoma. The images were interpreted by three experienced radiologists using a five-point rating scale, enabling receiver operating characteristic (ROC) analysis. Imaging results were evaluated against "truth" data based on analysis of surgical specimens from mediastinoscopy and thoracotomy. All MR images were cardiac gated to reduce cardiac motion artifacts in the mediastinum. MR and CT both performed well, as indicated by similar areas under the ROC curves of 0.779 +/- 0.039 for MR imaging and 0.781 +/- 0.038 for CT scanning. No strong correlation between nodal size and metastatic involvement could be found for either MR or CT results. As long as nodal size remains the sole criterion in the detection of metastatic mediastinal lymphadenopathy, MR imaging is unlikely to enable better interpretations than CT scanning.  相似文献   
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PurposeGenetic counseling may help counselees understand their genetic risk of developing breast/ovarian cancer. However, many studies have shown that their perception of their risks is inaccurate. Information-oriented variables often predicted the level of accuracy, focusing on specific processes of receiving and processing risks. We examined counselee-oriented predictors about how counselees embed cancer risks in their lives. These predictors reflect the personal meaning of genetic risks and are expected to explain/mediate the impact of genetic counseling on risk-perception-accuracy.MethodWe analyzed 248 questionnaires of a prospective study, filled in by probands with breast/ovarian cancer and pathogenic mutations, unclassified variants, or uninformative results (n = 30, 16, and 202, respectively). Mediation regression analyses were performed to examine whether counselee predictors mediated/explained the influence of information predictors on the accuracy. Information-oriented predictors regarded presentation format, communicated information, question format, education, pedigree information, cancer experience, and cognitive processes/heuristics. Counselee-oriented predictors regarded their self/personality, life/existence, and need for certainty about DNA test result, heredity, and cancer.ResultsBoth information-oriented and counselee-oriented variables significantly predicted the accuracy of the counselees' risk perception, with moderate to large effect sizes. Counselee-oriented variables completely mediated/explained the effects of information-oriented variables on the accuracy.DiscussionCounselees seemed to transform objective cancer risks into personally relevant information. Only through this personal meaning of genetic information, information-oriented processes seemed to cause inaccurate perceptions. Genetic counselors are suggested to focus communication on these personal processes.  相似文献   
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Pneumomediastinum can easily be mistaken for a pulmonary embolus or myocardial infarction. We describe herein a case of pneumomediastinum postpartum. A primigravida complained five-hours postpartum of acute chest pain and mild dyspnea. The initial (working) diagnosis was pulmonary embolus and the patient was treated with antithrombotic therapy. A CT scan revealed the real cause of the chest pain: pneumomediastinum. The patient was given adequate analgesia and two days later was able to leave the hospital in good clinical condition. We suggest that in the case of acute chest pain during or shortly following labor, pneumomediastinum should be considered.  相似文献   
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Aim: To determine the size of the growth deficit in Dutch monozygotic and dizygotic twins aged 0–2.5 years as compared to singletons and to construct reference growth charts for twins.
Methods: Growth of twins was studied using longitudinal data on over 4000 twins aged 0–2.5 years of the Netherlands Twin Register. The LMS method was used to obtain growth references for length/height, weight, and body mass index (BMI) for twins.
Results: During the first 2.5 years of age, differences in length/height and weight between twins and singletons decrease but do not disappear. BMI of twins deviates less than that of singletons. Approximately half of the growth retardation from birth until 1.5 years of age was attributable to gestational age. Between 1.5 years and 2.5 years of age, this difference was reduced to one-third. Thus, a substantial part of the growth difference could not be explained by gestational age.
Conclusions: During the first 2.5 years of life, there is a difference in growth between twins and singletons. Twins catch up in their body size, i.e. they grow faster after birth, but do not yet achieve the same height and weight till they reach 2.5 years of age. We recommend the use of the growth references for twins.  相似文献   
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Purpose: Intravascular ultrasound (IVUS) was used to assess in vitro the morphologic and quantitative effects of balloon angioplasty (PTA) of the iliac artery. Methods: Forty human iliac arteries (≥ 30% area stenosis) were studied with IVUS in vitro before and after PTA and the findings were validated with histology. Results: The sensitivity of IVUS for dissection was 74% and for media rupture 59%. The incidence of vascular damage was higher when the whole segment was analyzed rather than the target site alone. Dissections occurred at the thinnest region of the plaque, unrelated to plaque calcification. Following PTA, quantitative changes at the target site were greater compared with the overall data derived from all cross-sections. The increase in lumen area was caused solely by an increase in vessel area. Conclusions: IVUS is sensitive in detecting dissections, which occurred irrespective of calcification at the thinnest region of the plaque. The increase in lumen area after PTA was caused by stretching of the vessel.  相似文献   
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