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A patient presented with an ipsilateral orbital mass four years after enucleation for a choroidal malignant melanoma. Clinical examination revealed a darkly coloured mass suggestive of recurrent melanoma. CT scanning indicated a locally extensive tumour. Management was by excision without resort to orbital exenteration. Pathological examination revealed a cavernous haemangioma. The natural history of this tumour is discussed.  相似文献   
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A total of 143 patients with superficial G2 (pTa, pT1) bladder cancer (48 G2pTa; 95 G2pT1) presenting between 1970 through 1987 were reviewed. Of 48 patients with G2pTa followed for up to eighteen years, G3 recurrence developed only in 1 (2.0%), and invasive cancer (greater than pT2) developed only in 2 (4.2%). They both received radiotherapy and have responded completely. There have been no cancer-related deaths. In contrast, in the 95 patients in whom the basement membrane had been breached (pT1), higher grade tumor (G3) developed in 11 (11.5%), and 15 (16%) had recurrences with invasion of muscle (greater than pT2). Among these there were 7 (7.3%) cancer-related deaths.  相似文献   
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Long repetition time (TR) spin-echo (SE) with T2- or proton density weighting is the sequence of choice to detect the brain lesions of multiple sclerosis (MS). Fast spin-echo (FSE) permits the generation of T2-weighted images with similar contrast to SE but in a fraction of the time. We compared the sensitivity of FSE and SE in the detection of the brain lesions of MS. Six patients with clinically definite MS underwent brain imaging with both dual echo (long TR, long and short echo time (TE) SE and dual echo FSE. The SE and FSE images were first reviewed independently and then compared. A total of 404 lesions was detected on SE and 398 on FSE. Slightly more periventricular lesions were detected using SE than FSE (145 vs 127), whereas more posterior cranial fossa lesions were detected by FSE (77 vs 57). With both SE and FSE the short TE images revealed more lesions than the long echo. These results suggest that FSE could replace SE as the long TR sequence of choice in the investigation of MS.  相似文献   
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Lymphocytes of children with T cell and pre-B cell acute lymphocytic leukemia (ALL) were cultured in media with different concentrations of Fe, Cu and Zn to detect a possible effect of these ions on leukemic cells. Thymidine uptake was elevated in non-mitogen stimulated ALL cells and increased after mitogen stimulation, whereas intracellular ferritin, Fe and Cu, elevated before culture, decreased thereafter; pre-B ALL cells, positive only for cytoplasmic mu chains, became positive for surface immunoglobulins and released a detectable amount of them; low T4/T8 ratio in cells from T cell ALL returned to normal values after culture. These findings were present only in media with minimal concentrations of Fe, Cu and Zn and suggest that regulation of intracellular levels of these metals may induce some differentiation of leukemic cells.  相似文献   
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