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121.
Focused US system for MR imaging-guided tumor ablation 总被引:8,自引:0,他引:8
Cline HE; Hynynen K; Watkins RD; Adams WJ; Schenck JF; Ettinger RH; Freund WR; Vetro JP; Jolesz FA 《Radiology》1995,194(3):731
122.
Acquired alteration in the expression of blood groups in a patient with sideroblastic anemia and chronic renal failure 总被引:2,自引:0,他引:2
A patient with well-differentiated lymphocytic lymphoma in remission presented with renal failure, sideroblastic anemia, and an acquired diminution in the expression of A antigen on his red cells. Other red cell antigens (H, M, i, and I) also were expressed weakly. Lewis antigen was expressed only in secretions. The diminished expression of the A antigen could not be accounted for by diminution in the specific glycosyl transferases responsible for its expression, since the activity in the serum of both the H enzyme (alpha 1 leads to 2 fucosyltransferase) and the A enzyme (alpha 1 leads to 3 N-acetylgalactosaminyltransferase) was not diminished. When sialic acid was removed by enzymatic treatment, the expression of the A and i antigens was augmented markedly, suggesting that the sialic acid may have altered the expression or detection of the antigens. This abnormality was probably related to dysplasia of the bone marrow which was otherwise manifest by ringed sideroblasts, unsegmented megakaryocytes, and diminished growth in vitro. 相似文献
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124.
Semmler W; Gademann G; Bachert-Baumann P; Zabel HJ; Lorenz WJ; van Kaick G 《Radiology》1988,166(2):533-539
Tumors in 23 patients were studied by means of in vivo phosphorus-31 magnetic resonance (MR) spectroscopy. In five patients, the response to chemotherapy and radiation therapy was monitored in a long-term follow-up study. In one patient, the P-31 MR spectra were recorded during the infusion of chemotherapeutic drugs. In comparison with healthy muscle tissue of patients, the tumors showed elevated inorganic phosphate, phosphomonoester, and phosphodiester peaks and reduced creatine phosphate peaks, whereas the nucleoside 5'-triphosphate levels remained nearly unchanged. Tumor treatment resulted in changes in the ratio of the signal intensity value of creatine phosphate to that of inorganic phosphate and in the sum of these values. In an osteosarcoma, an initial response followed by renewed tumor growth was clearly indicated by changes in these parameters. In the short-term follow-up examination, slight spectral changes were observed during the infusion of chemotherapeutic drugs. Changes in the concentrations of phosphorus metabolites during therapy can therefore be monitored in human tumors by means of P-31 MR spectroscopy. 相似文献
125.
126.
Ultrasonography of the fetal cerebellum 总被引:3,自引:0,他引:3
The transverse diameter of the cerebellum was measured with ultrasound in 265 normal fetuses ranging from 15 to 39 weeks gestational age and found to correlate closely with the biparietal diameter. The transverse diameter may be useful in estimating fetal age, particularly in breech presentation where extrinsic pressure may deform the skull and decrease the biparietal diameter. Failure to demonstrate the cerebellum could be a sign of Arnold-Chiari malformation or Dandy-Walker cyst. 相似文献
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128.
Does preoperative needle localization lead to an increase in local breast cancer recurrence? 总被引:1,自引:0,他引:1
Kopans DB; Gallagher WJ; Swann CA; McCarthy KA; White G; Hall DA; Wood WC 《Radiology》1988,167(3):667-668
Between 1978 and 1981, 74 women with nonpalpable breast cancer underwent surgery after localization guides were placed. In 72 patients, guides were introduced parallel to the chest wall; in two the needle was positioned anteroposteriorly under computed tomographic guidance. Fifty-six cases (76%) were infiltrating cancer; 13 (17%), intraductal cancers; two (3%), inflammatory; and three (4%), lobular carcinoma in situ. Surgery was not used to treat the latter five patients. In the remaining 69 women, 42 (61%) were treated by means of modified radical mastectomy; six (9%), total mastectomy; 12 (17%), local excision and radiation therapy; and seven (10%), local excision alone; exact therapy for two women (3%) was unknown. At a minimum follow-up of 5 years, none of the 67 women in whom the parallel approach was used had a local recurrence. The authors conclude that preoperative placement of guides parallel to the chest wall does not appear to increase the risk of local breast cancer recurrence. 相似文献
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130.