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1.
Purpose: It was investigated whether alterations in neuronal structure and function occasioned by strabismic amblyopia also may be reflected in alterations in the expression on Y type neurons of a Cat-301 antibody sensitive antigen in the lateral geniculate nucleus (LGN) and cortex of our cat model of strabismic amblyopia. Methods/Results: The percentage of positively labelled cells was reduced in LGN laminae that received input from the deviated eye in strabismic amblyopic cats compared with normal cats. In the strabismic cortex, the density of immunopositive neurons was significantly reduced compared with normal, the effect being most pronounced in layer IV Conclusions: Despite previous physiological recordings indicating a decrease in X-cell associated acuity in strabismic amblyopia, the present findings imply that the changes in the early visual experience occasioned by strabismus also produce specific molecular changes in theY neuronal class.  相似文献   
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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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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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