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Observer performance tests were conducted to compare the effects on diagnostic accuracy of hard copy (film) versus video display and to determine the diagnostic merits of conventional negative ("white bone") versus positive ("black bone") video displays. Subjective preferences were elicited from each observer for each display modality, and diagnostic accuracy was determined with receiver operating characteristic analysis. Digitized chest radiographs were used, including normal and abnormal cases with a variety of subtle abnormalities. The hard copy was printed with a 1,024 X 1,024-matrix by a high-quality drum scanner in conventional white bone format only. The video images were displayed on a 1,023-line monitor (30 Hz, interlaced) in both white bone and black bone formats with fixed window and brightness settings. Most observers preferred hard copy to video, but preferences were sharply divided between white bone and black bone video. Diagnostic accuracy was significantly greater with hard copy than with video display, and the conventional white bone format was significantly superior in accuracy to the black bone display. 相似文献
275.
HP Busch 《European radiology》1997,7(11):66-72
LANGUAGE="EN">Summary. In the field of radiological research methods, digital imaging is becoming increasingly prevalent. Apart from computerised tomography, magnetic resonance tomography and angiography, also in projection radiography, traditional film/screen imaging is more and more being replaced by digital imaging using digital image-intensifier and storage phosphor technology. Digital imaging offers various new possibilities in image processing, storage and transmission. This may yield additional diagnostic information, dose reduction and fast availability of images. However, an inappropriate parameter selection for imaging and post-processing as well as a lack of integration in the entire organisation may lead to a rejection of this innovative technology. 相似文献
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I Palamaras† J El-Jabbour‡ N Pietropaolo† P Thomson† S Mann† W Robles† HP Stevens† 《Journal of the European Academy of Dermatology and Venereology》2008,22(9):1033-1043
Metastatic Crohn's disease (MCD) indicates the presence of non-caseating granuloma of the skin at sites separated from the gastrointestinal tract by normal tissue and is the least common dermatologic manifestation of CD. In adults, MCD usually appears after the initial diagnosis of CD in 70% of cases, whereas in children, it appears at the same time as CD in almost half of the cases. The most frequent skin lesions in adults are nodules, plaques with or without ulceration on the extremities and ulcers on the genitals. In children, genital swelling with or without erythema is the most frequent presentation of MCD. Simultaneous presence of perianal CD affects more females (60%) and particularly children. Associated gastrointestinal symptoms are present in one third of the cases in adults and in half of the cases in children. Treatment is often unsatisfactory. Randomised controlled trials are lacking. Various chemotherapeutic agents have been used such as oral metronidazole, topical and/or oral steroids, azathioprine, cyclosporine, sulfasalazine, tetracyclines, topical or systemic tacrolimus, infliximab alone or with methotrexate, and surgical treatment with oral zinc sulphate. MCD represents another 'great imitator'. This reviews the most relevant characteristics of this disease, in order to increase awareness and to avoid delay in diagnosis and improve management of the whole CD complex. 相似文献
278.
Chantal HP de Koning Sylvia P van den Heuvel J Bart Staal Bouwien CM Smits-Engelsman Erik JM Hendriks 《BMC musculoskeletal disorders》2008,9(1):142
Background
Neck pain is a significant health problem in modern society. There is evidence to suggest that neck muscle strength is reduced in patients with neck pain. This article provides a critical analysis of the research literature on the clinimetric properties of tests to measure neck muscle strength or endurance in patients with non-specific neck pain, which can be used in daily practice. 相似文献279.
PA Kowacs EJ Piovesan LC Werneck CE Tatsui MC Lange LC Ribas & HP da Silva 《Cephalalgia : an international journal of headache》2001,21(3):184-188
Thirty-three migraineurs and 23 healthy controls were submitted to pressure algometry before and after light-induced discomfort was elicited by progressive light stimulation in a monoblind fashion. Pressure algometries were performed on the emergence of the supraorbital, infraorbital, mental and greater occipital nerves, and over the temporal muscles, always throughout the same sequence and from right to left. Measurements were carried out before and immediately after light stimulation and after 10 min of the second algometry. The final result for each site measured at each time-point was the mean of the three measurements. Light stimulation was carried out progressively until light-induced discomfort was reported, to a maximum of 20,000 lux. A heat-blocking glass protected patients' eyes. Migraineurs presented significant and persistent drops in pain perception thresholds after light stimulation, at all sites tested (P = 0.002 to < 0.0001). These drops were not seen in controls, in whom, conversely, a less significant increase was seen on right infraorbital and left temporal muscle sites. Our results indicate that in migraineurs, light may have a relevant role in trigeminal and cervical pain perception thresholds. 相似文献
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