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排序方式: 共有290条查询结果,搜索用时 234 毫秒
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Impact of stereotaxic core breast biopsy on cost of diagnosis 总被引:6,自引:0,他引:6
Liberman L; Fahs MC; Dershaw DD; Bonaccio E; Abramson AF; Cohen MA; Hann LE 《Radiology》1995,195(3):633
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Structure, function, and degeneration of bovine hyaline cartilage: assessment with MR imaging in vitro 总被引:8,自引:0,他引:8
The basic magnetic resonance (MR) imaging pattern of normal and degenerated hyaline articular cartilage was studied in vitro in 40 fresh bovine patellae. With the use of an ample spectrum of strongly T1- to T2-weighted sequences, two zones of cartilage with different signal intensities were observed in all specimens. A superficial cartilaginous layer in the MR image with higher water content and longer T1 and T2 correlated with the tangential and transitional zones of normal articular cartilage, whereas a second MR imaging zone with shorter T1 and T2 was identified in the depth of the articular cartilage. Different functional properties in pressure resistance were observed in the two layers. In early cartilage degeneration without thinning, there was increased hydration of the superficial cartilage layer. This study suggests that strongly T1- and T2-weighted images are indispensable for evaluating details in articular cartilage degeneration. 相似文献
215.
FA Prado Vasques AF Moron CGV Murta FHC Carvalho MM Barbosa LA Marcolino 《The Ultrasound Review of Obstetrics & Gynecology》2004,4(2):121-125
The assessment of fetal well-being by venous Doppler velocimetry, especially in cases of intrauterine growth restriction, has been growing in importance as a number of researchers have been improving their studies1 - 5 as well as a consequence of better technologies in ultrasound equipment. Since different authors have studied the fetal blood circulation with color Doppler, initially focusing their attention on the arterial system6 - 12, many questions and doubts have remained without a reasonable answer, especially concerning the optimal time at which to deliver these fetuses. Among these authors, some have expressed the opinion that all biophysical methods, including the cardiotocogram, should be used before the decision of fetus delivery should be made13,14. It is possible, nowadays, to study several venous vessels, such as the ductus venosus, inferior vena cava, umbilical vein, portal vein, hepatic veins15, and, more recently1,2, the cerebral transverse sinus. The purpose of this review is to describe the fetal circulation, the technique and rationale behind measuring venous Dopplers and to assess the clinical applications of venous Doppler velocimetry. 相似文献
216.
COMMENTARY 总被引:1,自引:0,他引:1
AF Williams 《Acta paediatrica (Oslo, Norway : 1992)》2002,91(12):1282-1295
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MB Allen AF Mellon EJ Simmonds RL Page JM Littlewood 《Archives of disease in childhood》1993,69(2):197-201
Sleep related arterial oxygen desaturation has been described in clinically stable young adults with cystic fibrosis. The incidence and severity of nocturnal oxygen desaturation in children during infective exacerbations and the changes that occur with treatment were examined. Forty five children with proved cystic fibrosis, median age 8.9 years, admitted to the Regional Cystic Fibrosis Unit underwent clinical evaluation, spirometry, and measurement of peak flow and nocturnal oxygen saturation on admission and after 10 days' treatment. There was a significant improvement in all the above measurements, with the averaged overnight saturation changing from a mean (SD) 92.7 (2.7)% to 94.3 (2.0)%, mean (SE) difference 1.58 (0.37). The time spent with a saturation 4% or more below their clinic value showed a marked improvement from 122 (152) minutes on the first night to 21 (30.7) on the second, mean (SE) difference 101 (22.4). Eight young children could not perform pulmonary function tests, all desaturated on the admission night. Nocturnal hypoxaemia is a common finding in young cystic fibrosis patients during infective exacerbations but improves with treatment. Overnight oximetry is simple to perform, well tolerated, and identifies patients with marked nocturnal desaturation. 相似文献
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Establishment and characterization of a human plasma cell myeloma culture having a rearranged cellular myc proto-oncogene 总被引:9,自引:0,他引:9
Using a serum-free defined medium, we have established a human cell line, NCI-H929, from a malignant effusion occurring in a patient with IgAk myeloma. The cultured cells have the morphologic, ultrastructural, biochemical, immunologic, and cytochemical features of plasma cells. The cells have rearranged alpha and kappa genes and synthesize and secrete high amounts of IgAk (greater than 80 micrograms/10(6) cells per 24 hours). The cells express surface immunoglobulin (alpha and kappa), the plasma cell antigen PCA-1, the transferrin receptor (T9) and T10 but lack antigens associated with earlier stages of B cell development (HLA-DR, B1, B2, B4, CALLA), as well as other leukocyte- macrophage antigens and Epstein-Barr virus (EBV) nuclear antigen. Although molecular studies confirm that both the tumor and cultured cells are derived from the same clone of malignant B cells, the tumor cells were predominantly near-diploid, whereas the cultured cells are predominantly near-tetraploid with six copies of chromosome 8, four to six of which have an 8q + abnormality. However, both the tumor and the cultured cells have a rearrangement of the cellular c-myc proto- oncogene (located at 8q24) and express c-myc RNA. Although a modest number of human "plasmacytoid" cell lines have been established, most are lymphoblastoid lines lacking plasma cell features, while others appear to be early secretory cells. In contrast, NCI-H929 is a differentiated, highly secretory human plasma cell line. 相似文献