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Computed tomography of the thorax 总被引:2,自引:0,他引:2
Computed tomography (CT) provides a valuable new perspective in assessing abnormalities of the thorax. In the patient with a mediastinal mass or widening detected by plain chest radiography, a definitive diagnosis is sometimes possible which would not be obtainable by conventional noninvasive radiological techniques. In certain clinical situations, CT is a highly sensitive modality for examining the lungs. The proved and potential clinical uses of CT in solving diagnostic problems of the thorax are discussed. 相似文献
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CY Hang § SS Huang R. Wang YJ Sung† CF Kwok‡ § 《Clinical and experimental pharmacology & physiology》1998,25(2):99-103
1. Trilinolein is a triacylglycerol with linoleic acid as the only type of fatty acid in all three esterified positions of glycerol. It was recently reported to have a myocardial protective effect in coronary ligated rats. We now study its effect on the adhesion of human neutrophils to cultured bovine endothelial cells. 2. Pretreatment of an endothelial monolayer with trilinolein at concentrations ranging from 10-10 to 10-6 mol/L significantly inhibited neutrophil adhesion to endothelial cells. Trilinolein was less potent than sodium nitroprusside in inhibiting neutrophil adhesion. 3. The inhibitory effect of trilinolein was antagonized by methylene blue and NG-nitro-L-arginine methyl ester. The inhibitory effect of trilinolein was not mediated through linoleic acid because linoleic acid did not inhibit neutrophil adhesion. 4. Pretreatment of neutrophils with trilinolein did not reduce neutrophil adhesion. However, in neutrophils activated with N-formyl-methionyl-leucyl-phenylalanine, trilinolein inhibited the neutrophil adhesion to endothelial cells. 5. We conclude that trilinolein inhibits neutrophil adhesion to the endothelial monolayer by stimulating the nitric oxide and cyclic GMP pathways in endothelial cells. It may also inhibit neutrophil adhesion by scavenging free radicals. The inhibitory effect of trilinolein on neutrophil adhesion may play a role in its myocardial protective activity. 相似文献
106.
Two flavonoids were isolated from the leaves of Glycyrrhiza uralensis Fisch (Licorice, Leguminosae). On the basis of physico-chemical properties and spectroscopy (UV, 1HNMR and MS), a new compound was elucidated as 3,5,7,4′-tetrahydroxy-3′-methoxy- 6-isoprenyl flavone (gancaonin P-3′-methylether) and another known compound was identified as 8-C-prenyleriodictyol. 相似文献
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Pneumothorax: appearance on lateral chest radiographs 总被引:1,自引:0,他引:1
The appearance of pneumothorax on lateral radiographs obtained with the patient erect were reviewed in 100 patients (122 total examinations). A pneumothorax could be seen on the lateral projection in 89% of the examinations (109 of 122). The displaced pleural line was most frequently identified anteriorly or posteriorly and was less commonly identified at the lung apex or in a subpulmonic location. In 11 cases, an air-fluid level was the only recognizable finding of a pneumothorax on the lateral projection. Although in 27% of examinations (32 of 122) the pneumothorax was either not seen (11%) (n = 13) or was a subtle finding (16%) (n = 19), in 14% of examinations (17 of 122) the lateral projection provided helpful information to supplement the posteroanterior projection. 相似文献
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Hauben EI Bielack S Grimer R Jundt G Reichardt P Sydes M Taminiau AH Hogendoorn PC 《European journal of cancer (Oxford, England : 1990)》2006,42(4):460-466
Primary high-grade intramedullary osteosarcoma of the extremities is a clinically aggressive bone tumour. There is an ongoing effort to further improve efficacy of neo-adjuvant chemotherapy and reduce chemotoxicity by trying to identify osteosarcoma patients who are at risk of treatment failure as well as to identify those who can do with less chemotherapy. In only 5% of patients, first distant metastasis or local relapse occurs 5 years or more after initial treatment for osteosarcoma. Patients and physicians can therefore easily erroneously consider a patient with osteosarcoma cured if he or she is disease-free for more than 5 years following diagnosis and treatment. To investigate if these rare late relapsing patients are characterised by specific clinico-pathological features, we examined clinical and histological variables of late relapse (first local recurrence or metastasis 5 years or more after initial diagnosis) out of a total of 2,243 patients, with a special interest in the histological osteosarcoma subtype. In total, 33 patients had a documented relapse 5 years or more after diagnosis. Half of the patients had good response (>or=90% necrosis) to pre-operative chemotherapy and the other half a poor response (<90% necrosis) and late relapses seemed to be more frequently proportionately in those who had a good initial response to chemotherapy. The occurrence of late relapse did not appear to be associated with age or gender. Although not statistically significant, there was a trend for patients with a chondroblastic subtype of osteosarcoma, or a location in the tibia or fibula, to have a higher risk for late relapse. 相似文献
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