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991.
992.
Hanganutziu-Deicher heterophile antigen in human retinoblastoma cells   总被引:3,自引:0,他引:3  
We investigated the possible existence of Hanganutziu-Deicher antigen (HD antigen) on retinoblastoma cells by means of indirect membrane immunofluorescence and a complement-dependent antibody-mediated cytotoxicity test. We prepared antiserum in the chicken by immunization with purified equine hematoside highly specific to HD antigen. Three kinds of retinoblastoma cell lines, Y-79, WERI-Rb 1, and TOTL-1, showed positive membrane staining. Y-79 and TOTL-1 cells were also confirmed by the cytotoxicity test to possess HD antigen. Retinoblastoma cells freshly isolated from two patients had a positive membrane immunofluorescence. These results indicated that HD antigen was expressed in human retinoblastoma cells in vitro as well as in vivo.  相似文献   
993.
99mTechnetium dimercaptosuccinic acid renal scintigraphy, consisting of the cortical image and dimercaptosuccinic acid renal uptake rate, was used to assess preoperative and postoperative renal function in 55 patients with staghorn calculi. In 14 of 20 patients who had undergone extended pyelolithotomy and in 4 of 22 who had undergone nephrolithotomy there was an increase or no change in the postoperative dimercaptosuccinic acid renal uptake in the surgically treated kidney. However, there was no increase in the postoperative dimercaptosuccinic acid renal uptake in the patients who had undergone pyelolithotomy combined with nephrotomy or partial nephrectomy. Eight per cent of the preoperative dimercaptosuccinic acid renal uptake rate in the diseased kidney seems to be the absolute level for predicting the postoperative recovery of renal function. Dimercaptosuccinic acid renal images provide evidence of morphological changes in the cortex of the kidney with stones and the dimercaptosuccinic acid uptake rate is a useful adjunct for quantitative assessments of preoperative and postoperative residual cortical function.  相似文献   
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Intercellular communication (IC) was investigated by a dye transfer method in 5 human bladder carcinoma cell lines, JTC-29, JTC-30, JTC-32, HUB-41 and T-24 which showed various histological anaplasia when transplanted into nude mice. IC was investigated as follows; 1) IC among cells of each bladder carcinoma cell lines, 2) IC between various combination of different cell lines and 3) IC between cells of bladder carcinoma cell lines and fibroblasts prepared from the human skin or prostate. High IC was observed among JTC-30 cells which showed a differentiated pattern when transplanted into nude mice. JTC-32 and HUB-41, of which transplanted tumors showed poorly differentiated patterns, demonstrated lower IC than JTC-30. Statistical significance was present only between JTC-30 and JTC-32 cells (p less than 0.05). T-24 which formed histologically anaplastic tumor in nude mice demonstrated markedly poor IC. Second, IC between two different cell lines was demonstrated only between JTC-30 and JTC-32. Third, fibroblast from the skin and prostate had high IC but showed apparent IC with none of bladder carcinoma cell lines. These findings indicate that ICs of bladder tumor cells vary with cell lines tested and appear to decrease with progress of malignant anaplasia. Furthermore, the fact that there is sometimes high IC and sometimes lack of IC between differentiated and undifferentiated tumor cells suggests a possible role of IC in prevention of malignant progression. The present study provides no evidence of IC between bladder tumor cells and fibroblasts, which in some reports have been suggested to be an important phenomenon in evaluating the metastatic capacity of cancer cells.  相似文献   
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This study evaluated cerebral blood flow (CBF) by quantification and count profiles of hemispheric CBF using123I-IMP SPECT 10 days before and after surgical removal of an unilateral carotid stenosis in eight selected patients. The endarterectomized carotid artery was stenosed 35–90% in diameter, whereas the contralateral carotid artery was virtually normal. Preoperative CBF in the cerebral hemisphere was lower on the stenosed carotid artery side than on the contralateral side in seven of eight cases. After endarterectomy, hemispheric CBF increased on the operated side in six cases, and on the contralateral side in five, although to a lesser degree. The postoperative increase was prominent in cases having carotid stenosis over approximately 80%. These results indicate that the present method is useful in evaluating the intracranial hemodynamics of cases with carotid stenosis, thereby confirming that endarterectomy is effective in improving CBF in cases with a high degree of stenosis.  相似文献   
999.
MR was helpful in demonstrating the spatial relationship between a dermoid cyst in the fourth ventricle and an occipital dermal sinus. T1-weighted images clearly showed the mixed hypointense mass in the fourth ventricle and above the vermis, which appeared to be connected to an occipital dermal dimple.  相似文献   
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