中文摘要：

采用化学交联法制备超顺磁性氧化铁（SPIO）标记的C—erbB2癌基因反义脱氧寡核苷酸探针，经过1．5T磁共振仪测定，其T2弛豫率为0．156×10^6mol^-1·s^-1；振动样品磁强计测定出探针的磁化强度为69．4238emu／g Fe，比饱和磁化强度68．4134emu／g，比剩余磁化强度为30．3541emu／g，剩磁为19．7345Gs。为了检测探针的有效性，进一步使用该探针转染高表达c—erbB2癌基因的SK—Br-3肿瘤细胞株，同时使用正义和无义探针转染SK—Br-3肿瘤细胞株、反义探针转染正常小鼠肝细胞作对照，结果发现反义探针能够特异性进入SK-Br-3肿瘤细胞内，且能明显改善该细胞的磁学参数并降低磁共振扫描下的信号强度。

英文摘要：

The c-erbB2 oncogene antisense oligodeoxynucleotide probe was obtained by chemical cross-linking approach. Its T2 relaxivity was 0. 156 × 106 mo 1^-1· s^-1 , which was determined with a 1.5T MR system. The saturated magnetization, specific saturated magnetization, specific retentivity and retentivity were 69. 423 8emu/g Fe, 68. 413 4e mu/g, 30. 354 le mu/g and 19. 734 5 Gs, respectively. These measurements were obtained with a vibrating-sample magnetometer. To test its effectiveness, highly expressive SK-Br-3 oncocytes were transfected with the antisense oligodeoxynucleotide probe. Meanwhile, SK-Br-3 oncocytes were transfected with the sense and non-sense oligodeoxynucleotide probe, and normal mouse liver cells were transfected with the antisense oligodeoxynucleotide probe. The results show that the antisense probe could enter the SK-Br-3 oncocytes effectively, and improve the magnetic properties and decrease the signal intensity in MR scanning obviously.