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61.
This paper attempts to correlate morphological changes observed after ADR treatment with other cellular parameters. Experiments were carried out on control cells, ADR and cysteamine treated cells and the evaluation of DNA content and the determination of the pHi were studied using microspectrofluorimetry and Numerical Image Analysis. Results show that the DNA content and the pHi are modified significantly in presence of ADR but that no changes are observed when cells are treated with cysteamine alone. Furthermore no correlation could be established between these parameters and the class of cells that does not accumulate BaP. Further investigation will be necessary, first on other parameters such as intracellular Ca++, and second, by following parameters simultaneously on the same cell. 相似文献
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A series of compounds was synthesized, these compounds were tested for Hela-S3cells in vitro for radiosensitizing activity. Five of them are 2,2′- (arylimino)-diethyl-sodium thio-sulfate and two of them are phenylalanine derivatives. Most of them showed various degrees of ra-diosensitizing activity. Among them, SER of L07 was 1.89 at 3 mmol, and had low cytotoxicity toHela-S3 cells;ID50 was 18.8 mmol. The relationship between radiosensitizing effects and chemicalstructure was discussed. It offers a base for further exploration of selectively hypoxic cell radiosens-itizers. 相似文献
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M Vigo D De Faveri P R Biondetti L Benedetti 《Journal of computer assisted tomography》1980,4(5):627-629
Three cases of hepatocellular carcinoma in which computed tomography (CT) demonstrated thrombosis of the portal vein are reported. In one patient, extension of the thrombus into the superior mesenteric vein was identified as well. The outstanding CT features of portal vein thrombosis were: (a) enlargement of the vein, (b) intraluminal low density area, and (c) hyperdense peripheral ring due to the enhancement of the venous wall. These findings may be useful in differentiating hepatocellular carcinoma from hepatic metastases. 相似文献
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Turner DA; Alcorn FS; Shorey WD; Stelling CB; Mategrano VC; Merten CW; Silver B; Economou SG; Straus AK; Witt TR 《Radiology》1988,168(1):49-58
Detectability of breast cancer with magnetic resonance (MR) imaging versus xeromammography was quantitatively compared. MR images were obtained of breasts of 120 women who underwent xeromammography. T1 values were determined for masses larger than 2 cm. Cancer was histologically confirmed in 39 breasts and was considered excluded from 81 due to results of biopsy, cyst aspiration, or sonography or absence of change in xeromammographic findings over time. Images were blindly interpreted by three observers, and results were expressed as receiver operating characteristic curves. Detectability of breast cancer was substantially better with xeromammography than with MR imaging for all observers (P less than .03, 10(-6), and .001). On MR images, spiculation of a mass, distorted architecture, skin thickening, and nipple or skin retraction were specific but relatively insensitive indicators of cancer. Masses with smooth, distinct margins and signal intensity greater than that of fat on T2-weighted images were always benign. Other findings and T1 values were not diagnostically useful. The authors conclude that xeromammography is superior to MR imaging in detection of breast cancer. 相似文献