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排序方式: 共有907条查询结果,搜索用时 15 毫秒
851.
852.
Perianal fistulas: use of MR imaging for diagnosis 总被引:3,自引:0,他引:3
853.
Bladder cancer: staging with CT and MR imaging 总被引:10,自引:0,他引:10
Magnetic resonance (MR) imaging and computed tomography (CT) were compared in 30 patients with histologically proved bladder cancer. MR imaging was accurate in depicting the presence or absence of extravesical spread in 22 patients (accuracy, 73%; sensitivity, 82%; specificity, 62%), and CT was accurate in 24 patients (accuracy, 80%; sensitivity, 94%; specificity, 62%). The MR examinations of two patients were of undiagnostic quality and therefore considered to be technical failures. Each technique resulted in five false-positive and one false-negative examination for the diagnosis of extravesical tumor spread. In 28 patients the integrity of the bladder wall was assessed with MR imaging. In 22 patients the bladder wall was disrupted, and 18 of these patients had deep muscle invasion. In six patients the bladder wall was intact, and none of these patients had evidence of deep muscle invasion at pathologic examination. In this study MR imaging was slightly inferior to CT in the delineation of invasive tumors beyond the bladder wall. However, if one excludes from analysis the two patients with undiagnostic studies, there is no significant difference in accuracy between the two techniques. 相似文献
854.
Changes in cell spreading and cytoskeletal organization are induced by adhesion to a fibronectin-fibrin matrix 总被引:5,自引:1,他引:4
Plasma fibronectin (pFN) cross-linked to fibrin during the injury response provides a provisional matrix required for cells to begin tissue repair. Using a synthetic matrix of pFN and fibrin as a substrate for cell adhesion and spreading, we have determined that pFN covalently cross-linked to fibrin into a complex multimer is functionally distinct from pFN immobilized onto a plastic surface. NIH- 3T3 cells on a FN-fibrin matrix reach 50% of the maximal cell area of cells spread on FN-coated plastic. They neither attach nor spread on cross-linked fibrin alone. Cells on pFN-fibrin matrices form few prominent stress fibers and exhibit clear differences in membrane ruffling and filopodial extension when stained with rhodamine-labeled phalloidin. Interestingly, these differences are enhanced by upregulation of protein kinase C. These data suggest that cell-FN interactions can be modified by the molecular context of the protein within the extracellular matrix resulting in distinct cell morphology and cytoskeletal organization. 相似文献
855.
H Galjaard M Mekes D E Josselin de Jong JE M F Niermeijer 《Clinica chimica acta; international journal of clinical chemistry》1973,49(3):361-375
A method is described enabling prenatal diagnosis of glycogenosis II (Pompe's disease) within 7–10 days after amniocentesis in the 14th–16th week of pregnancy. The procedure is based on amniotic fluid cell cultivation on thin plastic foil, freezing and freeze-drying of the cells and subsequent microdissection of pieces of plastic foil each containing 70–250 lyophilized cells. These are incubated in microliter volumes of substrate. The extinction or fluorescence values are measured in microcuvettes adapted to a normal spectrofluorometer or in microcapillaries using a microscope spectrofluorometer design. The methods developed are compared with conventional biochemical analyses. 相似文献
856.
Pulse Cyclophosphamide for Severe Neuropsychiatric Lupus 总被引:1,自引:1,他引:0
BOUMPAS DT; YAMADA H; PATRONAS NJ; SCOTT D; KLIPPEL JH; BALOW JE 《QJM : monthly journal of the Association of Physicians》1991,81(3):975-984
We Studied the effect of parenteral pulse cyclophosphamide therapyin nine patients with active systemic lupus erythematosus andsevere central nervous system involvement. Seven patients hadfocal neurological deficits and/or seizures associated withabnormalities on cerebrospinal fluid analysis and/or magneticresonance imaging. Two patients had organic brain syndrome withpsychosis and normal cerebrospinal fluid and/or magnetic resonanceimaging analysis. Six patients were unresponsive to treatmentwith high dose corticosteroid. Cyclophosphamide 0.75–1.0g/m2 body surface area, was administered intravenously everymonth for at least 2 months. Eight patients had a complete recoveryor recovered with minor residuals. Cyclophosphamide was welltolerated with few side effects. We conclude that parenteralpulse cyclophosphamide is an effective adjunctive therapy forthe management of patients with active systemic lupus erythematosusand central nervous system symptoms. 相似文献
857.
858.
Skeletal metastases from hepatoma: frequency, distribution, and radiographic features 总被引:4,自引:0,他引:4
Over the past 6 years, the authors evaluated 300 patients with hepatoma as part of phase 1 and 2 treatment protocol trials. Analysis of the available clinical data and radiographic studies revealed 22 patients (7.3%) with skeletal metastases demonstrated by radiography, computed tomography (CT), and/or nuclear scintigraphy. The plain film appearance of skeletal metastases from hepatoma was osteolytic in all cases. CT scanning best demonstrated the expansile, destructive nature of these metastases, which were often associated with large, bulky soft-tissue masses. Skeletal metastases from hepatomas demonstrated increased radiotracer uptake on standard bone scans and were gallium avid, similar to the hepatoma itself. In addition, they could be targeted therapeutically with I-131 antiferritin immunoglobulin. The most frequent sites of skeletal metastases were the ribs, spine, femur, pelvis, and humerus. An initial symptom in ten patients was skeletal pain corresponding to the osseous metastases. In five patients, pathologic fractures of the proximal femur or humerus developed and required total hip replacement or open-reduction internal fixation. Patients with long-standing cirrhosis or known hepatocellular carcinoma who also have skeletal symptoms should be evaluated for possible osseous metastases. 相似文献
859.
Transvenous inferior vena caval filters were placed in 32 patients (21 bird's nest [BN] and 11 Kimray-Greenfield [K-G] filters). Positive contrast cavography was performed before and immediately after filter placement as well as during long-term follow-up studies. In 23 patients, computed tomographic (CT) scanning was also performed; in 10 patients, real-time ultrasound (US) study was used as an adjunct. CT scans of the BN filter showed one case of hemorrhage and one case of air embolism, both of which were not recognized at cavography. CT scanning of the K-G filter demonstrated two cases of deep penetration of the prongs and one large retroperitoneal hematoma. Real-time US scanning played a major role in checking the final position of the filter and in determining its stability during repositioning of the upper prongs of one BN filter. Noninvasive examinations, including CT and US scanning, are valuable adjuncts in immediate and long-term follow-up study of patients with inferior vena caval filters. 相似文献
860.