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Studies of Nondefective Adenovirus 2-Simian Virus 40 Hybrid Viruses. VI. Characterization of the DNA from Five Nondefective Hybrid Viruses 总被引:25,自引:22,他引:3 下载免费PDF全文
Patrick H. Henry Lowell E. Schnipper Richard J. Samaha Clyde S. Crumpacker Andrew M. Lewis Jr. Arthur S. Levine 《Journal of virology》1973,11(5):665-671
Certain biophysical characteristics of the DNA from each of the five nondefective adenovirus 2 (Ad2)-simian virus 40 (SV40) hybrid viruses (Ad2(+)ND(1), Ad2(+)ND(2), Ad2(+)ND(3), Ad2(+)ND(4), Ad2(+)ND(5)) have been determined. The guanine plus cytosine content varied from 55 to 57% and was not significantly different from that of nonhybrid Ad2 (56%), and the hybrid DNA molecules had mean molecular lengths which were similar to that of the standard, Ad2. The Ad2 and SV40 components of each hybrid were linked by alkali-resistant, presumably covalent bonds. The percentage of SV40 DNA in each hybrid virus was determined by hybridization with SV40 complementary RNA in a calibrated system. The results indicate that each hybrid virus DNA contains a different percentage of SV40 nucleotide sequences. The estimated size of the SV40 DNA component varies from 48,000 daltons for Ad2(+)ND(3) to 840,000 daltons for Ad2(+)ND(4), the latter being equivalent to between one-fourth and one-third of the SV40 genome. 相似文献
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Alpha(v)beta(6) integrin-A marker for the malignant potential of epithelial ovarian cancer. 总被引:2,自引:0,他引:2
Nuzhat Ahmed Clyde Riley Gregory E Rice Michael A Quinn Mark S Baker 《The journal of histochemistry and cytochemistry》2002,50(10):1371-1380
The mechanism(s) responsible for the progression of non-metastatic or borderline ovarian cancer to invasive Grade I/III ovarian cancer is still unknown. An epithelium-restricted integrin, alpha(v)beta(6), is present in malignant epithelia but not in normal epithelia. We studied the relative expression and distribution of alpha(v)beta(6) integrin in early and late-stage invasive (Grade I and Grade III) and non-invasive (benign and borderline) ovarian tumors of serous, mucinous, endometrioid, and clear-cell carcinoma subtypes, to assess its potential as a marker for epithelial ovarian cancer progression. Sixty-six specimens, including eight normal, 13 benign, 14 borderline, 13 Grade I, and 18 Grade III tumors were evaluated by immunohistochemistry (IHC) using a monoclonal antibody (MAb) against alpha(v)beta(6) integrin. Normal ovarian surface epithelium was negative for alpha(v)beta(6) integrin expression. All 45 carcinomas studied were positive, and the staining intensity significantly correlated with the grade of the tumor. The Grade III carcinomas of all types showed strong staining intensity. Only mucinous benign tissues were positive, and no reactivity was observed in benign serous neoplasms. On the basis of these observations, we hypothesize that the expression of alpha(v)beta(6) integrin is associated with epithelial ovarian cancer and that a gradual increase in the expression of the molecule may be a correlative index of the progression of this disease. 相似文献
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Silvia E. Lucangioli Clyde N. Carducci Valeria P. Tripodi Ernst Kenndler 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,765(2):336-120
The capacity factors of 16 anionic cholates (from six bile salts, including their glyco- and tauro-conjugates) were determined in a micellar electrokinetic chromatography (MEKC) system consisting of buffer, pH 7.5 (phosphate–boric acid; 20 mmol/l) with 50 mmol/l sodium dodecyl sulfate (SDS) as micelle former and 10% acetonitrile as organic modifier. The capacity factors of the fully dissociated, negatively charged analytes (ranging between 0.2 and 60) were calculated from their mobilities, with a reference background electrolyte (BGE) without SDS representing “free” solution. For comparison, the capacity factors were derived for a second reference BGE where the SDS concentration (5 mmol/l) is close to the critical micellar concentration (CMC). The capacity factors are compared with the logarithm of the octanol–water partition coefficient, log POW, as measure for lipophilicity. Clear disagreement between these two parameters is found especially for epimeric cholates with the hydroxy group in position 7. In contrast, fair relation between the capacity factor of the analytes and their CMC is observed both depending strongly on the orientation of the OH groups, and tauro-conjugation as well. In this respect the retention behaviour of the bile salts in MEKC seems to reflect their role as detergents in living systems, and might serve as model parameter beyond lipophilicity. 相似文献
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Tebogo M. Segolodi Faith L. Henderson Charles E. Rose Kyle T. Turner Clement Zeh Peter N. Fonjungo Richard Niska Clyde Hart Lynn A. Paxton 《PloS one》2014,9(4)