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71.
The comparison of dual phase Tc-99m MIBI and Tc-99m MDP scintimammography in the evaluation of breast masses: Preliminary report 总被引:1,自引:1,他引:0
Arslan N Ozturk E Ilgan S Narin Y Dundar S Tufan T Pekcan M Bayhan H 《Annals of nuclear medicine》2000,14(1):39-46
The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI. 相似文献
72.
Tsopelas C 《Nuclear medicine and biology》2000,27(8):797-802
Chemical stability of the naphthol-azo dye Evans Blue (EB) was examined in the presence of acidic stannous chloride (SnCl2), with a view to preparing an instant cold kit. EB was found to be reactive toward this reducing agent, yielding the metal-chelating molecule 1,7-diamino-8-naphthol-2,4-disulfonic acid at high acidity and high stannous concentrations. This reduction reaction was undesirable in the cold kit preparation. The conditions were determined where reduction was inhibited, at pH = 5.0 and with a mole ratio of EB to SnCl2 = [10:1], effecting the facile preparation of stable cold kits. Successful 99mTc-labeling of an EB cold kit using these conditions resulted in the desired product with 98% radiochemical purity. Based on the radiolabeling efficiencies of chosen model compounds, it was rationalized that 99mTc metal predominantly coordinated with the 1-amino-8-hydroxy groups in the EB molecule to form 99mTc-EB. 相似文献
73.
目的探讨正常心肌灌注显像放射性稀疏区的成因.材料与方法对5例猪心行99mTc-MIBI在体和离体心肌灌注显像,并用ROI技术测量左室各部位心肌的放射性水平(计数/像元),由该值在两种状态下的差值计算衰减程度(%).结果两种状态间壁后部和后壁放射性水平最低;在体心肌前壁中段衰减程度(7.9%)高于其前段和后段,该区衰减程度与胸壁厚度呈正相关;后壁衰减程度最高(11.9%).结论胸壁是造成前壁中段稀疏影的原因,膈肌是形成后壁稀疏影的重要原因之一.心肌图像重建时可根据衰减程度作适当补偿. 相似文献
74.
Terz Mrin Lszl Balkay Lajos Trn Zord T. Krasznai Judit Szab-Pli Zoltn Krasznai 《European journal of pharmaceutical sciences》2005,24(5):495-501
Miltefosine is a phospholipid analog that exhibits antineoplastic activity against breast cancer metastases, but its mechanism of action remains uncertain. The aim of this study was to investigate the transport mechanism for the removal of miltefosine and [99mTc]-hexakis-2-methoxyisobutyl isonitrile (99mTc-MIBI) from multidrug-resistant cells. The P-glycoprotein pump function, cell viability, and 99mTc-MIBI and 2-[18F]fluoro-2-deoxy-D-glucose (18FDG) uptakes were measured in NIH 3T3 (3T3) and NIH 3T3MDR1 G185 (3T3MDR1) mouse fibroblasts and human lymphoid B JY cells. Miltefosine treatment increased the permeability and fluidity of these tumor cells in a concentration-dependent manner. The multidrug-sensitive cells were 3-4 times more sensitive to miltefosine than the multidrug-resistant ones. The extent of 99mTc-MIBI accumulation in the P-glycoprotein-expressing cells increased in the presence of miltefosine, whereas the rhodamine123 and daunorubicin uptakes of the cells did not change significantly. In the 3T3MDR1 cells verapamil reinstated the rhodamine123 and daunorubicin accumulation, but not the 99mTc-MIBI uptake. Cyclosporin A reinstated the uptakes of 99mTc-MIBI, daunorubicin and rhodamine123 by the 3T3MDR1 cells. In a concentration-dependent manner miltefosine decreased the extents of 99mTc-MIBI, rhodamine123, daunorubicin and 18FDG accumulation in the JY and 3T3 cells. Our findings indicate a common transport mechanism for 99mTc-MIBI and miltefosine, which is distinct from that for rhodamine123 and daunorubicin in MDR cells. 相似文献
75.
目的 评价 1 53钐 -乙二胺四亚甲基膦酸盐 (1 53Sm- EDTMP)与 99m Tc亚甲基二膦酸盐 (商品名云克 )联合应用治疗多发性骨转移癌的疗效。方法 各种骨转移癌 132例 ,随机分组治疗 ,第 1组 4 2例患者仅静脉注射 1 53Sm- EDTMP,1.0× 10 7Bq/ kg,第 2组 5 0例患者 1 53Sm- EDTMP联合 99m Tc亚甲基二膦酸盐治疗 ,1 53Sm- EDTMP用量不变 ,并与静脉注射 1 53Sm- EDTMP后的第 5天开始用 99m Tc亚甲基二膦酸盐连续 5 d。第 3组 4 0例患者静脉滴注博宁 ,10 d1个疗程。结果 第 1组镇痛有效率为 6 1% ,疼痛缓解持续时间平均 4周。第 2组联合用药组镇痛有效率达 80 % ,疼痛缓解持续时间平均 8周。第 3组镇痛有效率 4 2 % ,疼痛缓解持续时间平均 2周。 3组疗效有显著统计学意义 (P<0 .0 5 )。结论 不论 1 53Sm - EDTMP单独使用还是与 99m Tc亚甲基二膦酸盐联合用药都是治疗多发骨转移的有效止痛方法 ,相比之下 ,联合用药可明显提高镇痛效率。 相似文献
76.
目的探讨99mTc-YIGSR作为一种新型的肿瘤显像剂在埃氏腹水肿瘤受体显像中的应用价值。方法①制备99mTc-MAG3-YIGSR探针,以S-乙基-琥珀酰亚胺-巯乙苷肽(S-Acetly-NHS-MAG3)为螯合剂,将99mTc标记到层黏素多肽片断YIGSR上;②对肿瘤模型组及封闭模型组行99mTc-YIGSR生物学分布实验;③观察肿瘤模型组、炎症模型组及封闭模型组动物模型显像。结果①反相Sep-Pak C18柱层析结果表明,YIGSR可以很好地与S-Acetly-NHS-MAG3偶联,偶联物在室温及中性条件下可完成99mTc标记,标记率为62%,纯化后放射化学纯度>95%。室温放置1、2、4 h,放射化学纯度分别是91%,86%及81%。未与S-Acetly-NHS-MAG3偶联之YIGSR进行标记时,标记率为4%;②生物学分布结果显示,99mTc-YIGSR在小鼠血液内清除迅速,主要经肾脏排泄,其次为肝脏;③99mTc-YIGSR静脉注入肿瘤模型组小鼠体内后,15 min肿瘤部位有摄取,3 h摄取达高峰,肿瘤/对侧肢体比值为11.36,此后显像剂清除较为缓慢,8 h时下降至7.50。封闭模型组肿瘤细胞的摄取明显低下,肿瘤/对侧肢体比值是4.61(3 h)、0.89(8 h);炎症模型组中,炎症/对侧肢体比值是3.72(3 h)、1.29(8 h)。与炎症模型组及封闭模型组比较,肿瘤模型组3 h、8 h肿瘤/对侧肢体的比值明显增高(P<0.01)。结论通过螯合剂S-Acetly-NHS-MAG3可顺利完成层黏素多肽片段YIGSR的99mTc标记。99mTc-YIGSR用于肿瘤显像具有显像时间早,显像清晰,灵敏度高,特异性强,靶/非靶比值高等特点,是一种有发展前景的新型肿瘤受体显像剂。 相似文献
77.
78.
目的观察化疔增敏剂对多药耐药性(Multi-drug resistance,MDR)肿瘤细胞 P-糖蛋白(P-glycoprotein,P-gp)的影响及伴随~(99)Tc~m-MI-BI 摄取动力学的变化,以建立用~(99)Tc~m-MIBI 来评价化疗增敏剂效果的方法。方法 MDR 人乳腺癌细胞 MCF-7/Adr 37℃培养。(1)实验组和对照组细胞培养基中分别加入化疗增敏剂维拉帕米(10 μmol/L)和等体积培养液 DMEM。~(99)Tc~m-MIBI 与细胞共同孵育2 h 后收集细胞,测定放射性活度和 P-gp 表达水平。(2)维拉帕米(10 μmol/L)加入细胞培养基中,与细胞孵育若干时间后~(99)Tc~m-MIBI 加入细胞培养基中,与细胞一起培养2 h 后收集细胞。测定放射性活度和P-gp 表达水平。结果 (1)维拉帕米作用2h 后,细胞摄取~(99)Tc~m-MIBI 较对照组显著增加(t=2.33,P<0.05),但 P-gp 表达水平差异无显著性(P>0.05)。(2)肿瘤细胞摄取~(99)Tc~m-MIBI 随维拉帕米作用时间的延长而增加,各时间点 UR 差异有显著性(F=58.2,P<0.05),并且,VRP 作用时间在80 min 内时,肿瘤细胞摄取~(99)Tc~m-MIBI 与 P-gp 的表达水平无相关性(r=0.16,P>0.05),VRP 作用时间大于8 h时,肿瘤细胞摄取~(99)Tc~m-MIBI 与 P-gp 的表达水平呈负相关(r=-0.73,P<0.01)。结论化疗增敏剂能够影响 P-gp 过度表达所致 MDR 肿瘤细胞对~(99)Tc~m-MIBI 的摄取。 相似文献
79.
Hashimoto T Goto K Hishinuma Y Yachuda K Sugioka Y Arai K Harada S Goto M 《Annals of nuclear medicine》2000,14(4):293-298
99mTc-tetrofosmin, Thallium-201-chloride (201Tl) and 99mTc-MIBI imagings were performed in a patient with malignant thymoma. Tracer uptake in the primary tumor was demonstrated. The tumor-to-background ratios of planar and SPECT imagings were 1.60 and 1.98 for 99mTc-tetrofosmin, 1.12 and 2.09 for 201Tl, and 1.19 and 1.80 for 99mTc-MIBI, respectively. In another patient 99mTc-tetrofosmin and 201Tl imagings were performed. Not only the primary tumor but also the direct invasions and metastatic lesions (bone metastases) were clearly detected. The tumor-to-background ratios of planar and SPECT imagings were 2.31 and 2.78 for 99mTc-tetrofosmin and 2.45 and 3.58 for 201Tl, respectively. In 99mTc-tetrofosmin scintigraphy we acquired delayed images, and the tumor-to-background ratios of planar and SPECT delayed images were 1.20 and 1.86, the retention ratios were -1.11 and -0.92 and the retention indices were -48.1 and -33.1, respectively. Our preliminary results suggest that 99mTc-tetrofosmin is useful in detecting not only the primary tumor but also metastatic lesions from malignant thymoma. 相似文献
80.
Nishiguchi S Shiomi S Sasaki N Iwata Y Tanaka H Kubo S Hirohashi K Ochi H 《Annals of nuclear medicine》2000,14(5):383-386
A 39-year-old woman with acute cholecystitis and gallstones underwent laparoscopic cholecystectomy. She suffered from recurrent episodes of cholangitis due to injury of the major bile ducts during laparoscopic cholecystectomy. Hepatobiliary scintigraphy with Tc-99m Sn-N-pyridoxyl-5-methyltryptophan was performed. Although normal bile excretion was found from the left hepatic duct to the percutaneous transhepatic biliary drainage (PTBD) tube, excretion from the right hepatic lobe was prolonged. Scintigraphy with Tc-99m diethylenetriaminepentaacetic acid-galactosyl human serum albumin demonstrated atrophy of the right hepatic lobe and enlargement of the left hepatic lobe. Cholangiography via the PTBD tube revealed complete obstruction of the left hepatico-jejunal anastomosis and could not enhance the right intrahepatic bile duct. A right hepatic lobectomy was performed because of the atrophy, glissonitis and the absence of an appropriate bile duct for reconstruction. Postoperatively she was active and exhibited no evidence of recurrent cholangitis. 相似文献