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排序方式: 共有955条查询结果,搜索用时 15 毫秒
1.
Preliminary evidence for a role of apolipoprotein E alleles in identifying haemodialysis patients at high vascular risk 总被引:1,自引:0,他引:1
Olmer M; Renucci JE; Planells R; Bouchouareb D; Purgus R 《Nephrology, dialysis, transplantation》1997,12(4):691-693
Conventional risk factors have very low predictive power in identifying
haemodialysis patients at high risk of vascular accidents. A role for
apolipoprotein E isotypes was looked for in a small, but rigorously
defined, cohort of longterm haemodialysis patients. In individuals with
high vascular risk, as identified by higher common carotid intima/media
thickness, we found an excess of apolipoprotein E4 alleles. This
preliminary result requires confirmation in large patient cohorts.
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2.
Computed tomography as a screening exam in patients with suspected blunt aortic injury. 总被引:1,自引:1,他引:0 下载免费PDF全文
R M Durham D Zuckerman M Wolverson E Heiberg W B Luchtefeld D J Herr M J Shapiro J E Mazuski Z Salimi M Sundaram 《Annals of surgery》1994,220(5):699-704
BACKGROUND: Chest computed tomography (CT) screening of patients with blunt trauma for thoracic aortic injury is controversial. This study was undertaken to determine whether CT could exclude aortic injury and be used to select patients for aortography. METHODS: Computed tomography and aortography were used to evaluate 155 patients with blunt trauma. Computed tomography scans were reviewed separately by four attending radiologists who were unaware of the patients' clinical course and angiographic findings. RESULTS: Eight of 155 patients had aortic injuries requiring operation. Computed tomography scans in five patients were read as positive by all reviewers. One scan was read as positive by three reviewers and as negative by one. Two scans were read as positive by two radiologists and as negative by two. After poor scans were excluded, the combined sensitivity of CT for detecting aortic injury was 88%, specificity was 54%, positive predictive value was 9%, and negative predictive value 99%. CONCLUSIONS: The sensitivity of CT scan for indicating the need for aortography is observer dependent. As CT manifestations of aortic injury are often subtle, CT does not reliably exclude aortic injury. 相似文献
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Direct effects of endotoxin on hepatocytes. Synthesis of a specific secretory protein 总被引:2,自引:0,他引:2
J E Mazuski J L Platt M A West R L Simmons H C Towle F B Cerra 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(3):340-344
The synthesis of acute-phase proteins by the liver during sepsis has been thought to be induced primarily by monokines released from activated macrophages, although glucocorticoid hormones may also stimulate this process to a lesser degree. According to this concept, synthesis of these proteins following administration of bacterial endotoxins would be an indirect effect and would not reflect a direct interaction of the endotoxin molecule with the hepatic parenchymal cell. We observed, however, that the synthesis of a 23-kilodalton protein was stimulated directly by the addition of lipopolysaccharide to cultures of primary mouse hepatocytes. The synthesis of this protein was also stimulated by glucocorticoids and interleukin 1. These findings demonstrate that certain hepatic proteins are subject to complex regulation by several factors thought to be important mediators of sepsis; in addition, they suggest that hepatic parenchymal cells may have the intrinsic capacity to respond directly to bacterial endotoxins. 相似文献
6.
Hodgkin disease: CT of the thymus 总被引:2,自引:0,他引:2
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement. 相似文献
7.
Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
8.
A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
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