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991.
992.
Percutaneous laser thermal angioplasty: initial results and 1-year follow-up in 129 femoropopliteal lesions 总被引:2,自引:0,他引:2
Percutaneous peripheral laser thermal angioplasty with a laser-heated metallic-capped fiber was used as an adjunct to conventional balloon angioplasty. Initial angiographic and clinical success was achieved in 99 of 129 (77%) femoropopliteal stenoses and occlusions (21 of 22 [95%] stenoses, 17 of 17 [100%] short [1-3-cm] occlusions, 26 of 37 [70%] medium-length [4-7-cm] occlusions, and 35 of 53 [66%] long [greater than 7 cm] occlusions). There was a 4% frequency of vessel perforation without clinical sequelae and no necessity for emergency bypass surgery. The 1-year cumulative clinical patency was 77% for the 99 lesions with an initial clinical success. In the 21 stenoses and 17 short occlusions, the cumulative clinical patency rates were 95% and 93%, respectively. In the longer occlusions (4-7 cm and greater than 7 cm), the clinical patency rates were 76% and 58%, respectively. The initial angiographic and clinical success, as well as the 1-year cumulative clinical patency, for stenoses and short occlusions after laser-assisted balloon angioplasty may be greater than after conventional balloon angioplasty alone. 相似文献
993.
994.
995.
Juvenile rheumatoid arthritis: assessment with MR imaging 总被引:11,自引:0,他引:11
Thirty-three joints of the appendicular skeleton in 15 children with juvenile rheumatoid arthritis were examined with magnetic resonance (MR) imaging to determine if it could demonstrate synovial hypertrophy and status of the articular cartilage. Presumed synovial hypertrophy was seen in 13 joints as masses of varying sizes of low to intermediate signal intensity on T1- and T2-weighted images; sometimes foci of increased signal intensity, most likely due to fluid or inflammation, were seen on T2-weighted images. Probable abnormal articular cartilage was detected in ten joints, and MR imaging also demonstrated epiphyseal overgrowth, bone erosions, joint effusions, and joint space narrowing. Because MR imaging appears to provide an objective method of evaluating both synovial hypertrophy and status of articular cartilage, it may prove to be useful in monitoring progression of juvenile rheumatoid arthritis and response to therapy. 相似文献
996.
997.
To enhance the information provided by computed tomography (CT) and single photon emission computed tomography (SPECT) performed with radiolabeled, anti-carcinoembryonic antigen monoclonal antibody (MoAb), the authors performed fusion of these types of images from eight subjects with suspected colorectal adenocarcinoma. Section thickness and pixel size of the two studies were matched, coordinates of corresponding points from each study were identified, and CT sections were translated, rotated, and reprojected to match the corresponding SPECT scans. The CT-SPECT fusion enabled identification of anatomic sites of tumor-specific MoAb accumulation in four cases, showed non-specific MoAb accumulation in two, and helped confirm information only suggested by the two studies separately in one. 相似文献
998.
999.
Acute leukemias associated with the 4;11 chromosome translocation have rearranged immunoglobulin heavy chain genes 总被引:1,自引:1,他引:0
Crist WM; Cleary ML; Grossi CE; Prasthofer EF; Heggie GD; Omura GA; Carroll AJ; Link MP; Sklar J 《Blood》1985,66(1):33-38
Studies of acute leukemia with the 4;11 translocation have yielded conflicting results regarding the lineage of the cell of origin in this disease. To investigate this issue further, we have examined the state of immunoglobulin genes in tumor cells from two affected patients, immunophenotyped their leukemic cells using a number of monoclonal antibody reagents with specificities for lymphoid or myelomonocytic antigens, and examined the malignant cells by electron microscopy. DNA was extracted from leukemic bone marrow cells and hybridized with radiolabeled DNA fragment probes specific for the constant region of immunoglobulin heavy chain and kappa and lambda light chain genes. Autoradiographs revealed rearrangement of both allelic heavy chain genes, but a germline configuration of light chain genes in both cases. Surface marker analysis showed that blasts from both patients expressed HLA-DR and the myeloid antigens Leu-M1, 1C2, 2D1, and 4B3, but lacked common acute lymphocytic leukemia antigen or T antigens. Furthermore, they did not have sheep erythrocyte receptors nor did they express surface or cytoplasmic immunoglobulin or B cell precursor determinants. Electron microscopy analysis showed that blast cells from patient 1 exhibited numerous monoribosomes, polyribosomes, and isolated strands of rough endoplasmic reticulum in their cytoplasm. These ultrastructural features are characteristic for both common acute lymphocytic leukemia and pre-B-ALL cells, but not for T-ALL or acute myelogenous leukemia cells. Peroxidase was undetectable in cells from both patients. Our study suggests that this disorder represents a unique subtype of leukemia. The cell of origin may be an early B cell progenitor that shares certain surface antigens with myeloid cells or a stem cell with the potential for both lymphoid and myelomonocytic differentiation. 相似文献
1000.
Axial bone density in rheumatoid arthritis: comparison of dual-energy projection radiography and dual-photon absorptiometry 总被引:2,自引:0,他引:2
O'Malley M; Kenrick AJ; Sartoris DJ; Hochberg AM; Weisman MH; Ramos E; Zvaifler N; Resnick D 《Radiology》1989,170(2):501-505
The usefulness of dual-energy projection radiography (DEPR) in the evaluation of rheumatoid arthritis was compared with that of dual-photon absorptiometry (DPA). Bone density measurements of the lumbar spine and the proximal femur were obtained with DPA in 75 patients (45 women and 30 men). For comparison, the bone density of the lumbar spine was measured with DEPR in a subset of 52 patients (33 women and 19 men). High correlation was documented between DEPR and DPA measurements of the lumbar spine. No significant relationship between bone density and age was observed, in contrast to the known relationship in healthy subjects regardless of sex, site of measurement, or measurement technique. Bone density values in the spine and the proximal femur were significantly reduced for both sexes as compared with matched normative data. Interlevel variation in lumbar vertebral density as measured with DEPR was not significantly different in patients with rheumatoid arthritis as compared with control subjects. Significant correlation between bone density determination and body weight, as well as duration of menopause, was noted, whereas duration of disease, functional status, and cumulative corticosteroid dose were not predictive. Rheumatoid arthritis did not appear to influence the relationship between DEPR and DPA measurements of the spine, and neither method nor site of measurement exhibited a consistent advantage in discriminating patients with rheumatoid arthritis from healthy control subjects. 相似文献