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排序方式: 共有673条查询结果,搜索用时 31 毫秒
81.
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Cystic intracranial lesions: magnetic resonance imaging 总被引:4,自引:0,他引:4
Kjos BO; Brant-Zawadzki M; Kucharczyk W; Kelly WM; Norman D; Newton TH 《Radiology》1985,155(2):363-369
Thirty-three patients with cystic intracranial lesions were examined with both magnetic resonance (MR) imaging and CT scanning. The abnormalities imaged included 11 arachnoid cysts, 10 cystic tumors, six postoperative cysts, and three colloid cysts. The intensity patterns of the cyst contents as encoded with routine spin-echo imaging sequences enabled subdivision of the cysts into three categories. Arachnoid and postoperative cysts had an intensity pattern identical to cerebrospinal fluid. More proteinaceous cysts, including inflammatory cysts and nonhemorrhagic tumoral cysts, had an intermediate intensity pattern with characteristically low intensity on the short TR sequence (0.5 sec), but had clearly higher intensity than cerebrospinal fluid on the long TR sequences (2 sec). Finally, three cystic tumors with hemorrhagic fluid and three colloid cysts had a distinctly different pattern of high intensity on all four MR sequences through the same section. MR was superior to CT in characterizing intracranial cystic lesions because of its ability to categorize cysts into these three groups on the basis of the intensity pattern of cyst contents, thereby improving diagnostic specificity and patient management. 相似文献
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Endoscopic retrograde biliary drainage 总被引:1,自引:0,他引:1
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J Philip W G Harris C Flaherty C A Joslin J H Rustage D P Wijesinghe 《British journal of cancer》1984,50(1):7-12
As part of the Department of Health's National Breast Screening Trial a seven year study is in progress in Huddersfield to assess the effect of an educational programme in Breast Self Examination (BSE) on the mortality due to breast cancer among women aged 45-64. The initial cohort of 22,484 women have completed 3 years in the study and show a higher than expected annual incidence rate of breast cancer. There is no significant difference in the incidence rates between those who attended meetings for BSE instruction and those who did not. Similarly there is no difference in stages of presentation of cancers between attenders and non-attenders at these meetings and also between cancers detected in the first, second and third years. Those who discovered abnormalities during self examination, however, presented with smaller lumps compared to other women. Assessment of prognostic factors do not at this time provide sufficient evidence to show that a community-base BSE campaign will result in a significant improvement in the stage of breast cancer presentation. 相似文献
87.
Kim WM; Merskey C; Deming QB; Adel HN; Wolinsky H; Clarkson TB; Lofland HB 《Blood》1976,47(2):275-286
Inbred Carworth Farms Nelson (CFN) congenitally hyperlipidemic rats had significantly shorter coagulation and prothrombin times and higher levels of coagulation factors, II, V, VII, VIII, and X than did controls. Conversely, congenitally hypolipidemic rats of the same strain had significantly longer coagulation and prothrombin times and lower levels of factors II, V, VII, X and XII and of blood platelets than did controls. A loop-shaped polyethylene cannula was inserted into the aorta to assess the potential for thrombosis. The hyperlipidemic group obstructed this significantly faster and the hypolipidemic group slower than did the controls. Normal CFN rats made hypertensive by unilateral renal artery clip developed hypertension together with significantly elevated serum cholesterol and factor VII and X levels. Rhesus monkeys with diet-induced hyperlipidemia showed shorter prothrombin times and higher factor X levels than did controls on normal diet. By selective breeding, two groups of squirrel monkeys were obtained. Both groups had similar serum cholesterol levels on a normal diet but one group (hyperresponders) showed higher serum cholesterol levels on a cholesterol-containing diet than did the other (hyporesponder) group. Both groups showed significantly elevated levels of factors II, V, VII, IX and X on a cholesterol-containing diet. There was good correlation between the levels of many coagulation factors and serum cholesterol in both rats and monkeys. If thrombosis is important in the genesis of atherosclerosis, these findings could indicate that elevation of plasma lipids may play a role, via the coagulation pathway, in the production of human vascular disease. 相似文献
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