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排序方式: 共有756条查询结果,搜索用时 20 毫秒
41.
42.
Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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44.
A Holden JEM Anderson FJ Ives D Taylor EJ Wylie FRACR R Adamson 《Journal of Medical Imaging and Radiation Oncology》1996,40(4):391-397
The early clinical experience with a 3-Dimensional Fourier Transform Gradient Echo sequence with fat suppression in the evaluation of breast masses is reported. Ten female patients with breast malignancies were pre-operatively evaluated with this sequence and the results compared with the pathological specimens. The scanning protocol included a noncontrast sequence followed by an immediate post-contrast sequence (completed 4.5 min after intravenous contrast injection) and a delayed sequence. Images were assessed for maximum lesion and parenchymal enhancement, lesion size and additional enhancing abnormalities. In six patients, malignant masses enhanced maximally on the immediate post-contrast sequence with parenchyma enhancing maximally on delayed images. In three cases, there was preferential enhancement of malignant lesions over normal parenchyma but to a similar degree on both post-contrast sequences. In one case, both the lesion and parenchyma enhanced maximally on the delayed sequence. Magnetic resonance assessed lesion size accurately and also detected satellite malignancies in one case. However, lesion grade, associated in situ carcinoma and lymphovascular invasion did not impact on lesion enhancement. In this small series, a contrast-enhanced, fat-suppressed 3-D Gradient Echo Sequence detected breast carcinoma with high sensitivity. The technique holds promise but further evaluation is required. 相似文献
45.
Van Someren EJ 《Experimental gerontology》2000,35(9-10):1229-1237
The incidence of disturbed sleep is strongly increased in healthy and demented elderly. Age-related alterations in the circadian timing system appear to contribute strongly to these problems. With increasing age, a lack of input to the suprachiasmatic nucleus (SCN), the biological clock of the brain, may accelerate de-activation of neurons involved in the generation of 24-h rhythm or output of this rhythm. This process appears to be reversible, since supplementation of stimuli that impinge on the SCN can re-activate these neurons and ameliorate disturbances in the sleep–wake rhythm. 相似文献
46.
Computed tomography of gastrointestinal lymphoma 总被引:2,自引:0,他引:2
A J Megibow E J Balthazar D P Naidich M A Bosniak 《AJR. American journal of roentgenology》1983,141(3):541-547
From 275 computed tomographic (CT) examinations with positive findings of abdominal lymphoma, 26 patients were found to have gastrointestinal involvement by the disease. The stomach was most commonly involved, followed by small bowel, colon, and duodenum. CT was found to be accurate in detecting wall thickening and complications such as perforation and fistulization. False-negative examinations occurred in two patients with small submucosal gastric deposits ("bull's-eye" lesions). False-positive examinations were seen in two patients with hypertrophic gastritis. The CT manifestations of gastrointestinal lymphoma, correlated with the barium study appearance, are the subject of this report. 相似文献
47.
48.
Janaica EJ Grispen Gaby Ronda Geert-Jan Dinant Nanne K de Vries Trudy van der Weijden 《BMC public health》2011,11(1):112
Background
Although self-tests are increasingly available and widely used, it is not clear whether their use is beneficial to the users, and little is known concerning the determinants of self-test use. The aim of this study was to identify the determinants of self-test use for cholesterol, glucose, and HIV, and to examine whether these are similar across these tests. Self-testing was defined as using in-vitro tests on body materials, initiated by consumers with the aim of diagnosing a particular disorder, condition, or risk factor for disease. 相似文献49.
Brajendra K Singh Nicholas J Savill Neil M Ferguson Chris Robertson Mark EJ Woolhouse 《BMC public health》2010,10(1):726
Background
Key to the control of pandemic influenza are surveillance systems that raise alarms rapidly and sensitively. In addition, they must minimise false alarms during a normal influenza season. We develop a method that uses historical syndromic influenza data from the existing surveillance system 'SERVIS' (Scottish Enhanced Respiratory Virus Infection Surveillance) for influenza-like illness (ILI) in Scotland. 相似文献50.
Janaica EJ Grispen Martine HP Ickenroth Nanne K de Vries Geert-Jan Dinant Gaby Ronda Trudy van der Weijden 《BMC public health》2010,10(1):453