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101.
Liu Z  Ng EK  Liang NC  Deng YF  Leung BC  Chen GG 《FEBS letters》2005,579(6):1477-1487
In this study, we demonstrated that Ent-11alpha-hydroxy-15-oxo-kaur-16-en-19-oic-acid (5F) had stronger cytotoxicity against MKN-45, a gastric cancer cell line bearing wild-type p53 than MKN-28, another gastric cancer cell line containing missense mutation in p53. The rapid increase of ROS level was involved in the mechanism of cytotoxicity. Classical features of apoptosis induced by 5F were observed in MKN-45 cells only or more significant in MKN-45 cells than MKN-28 cells. Translocation of Bax from cytosol to mitochondria, reduction of delta psi m and DNA fragmentation were induced by 5F in the p53-dependent manner. We conclude that the expression of Bax and its downstream molecules requires the presentation of a wild-type p53 in the cells treated by 5F.  相似文献   
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Chen L  Li G  Tang L  Wang J  Ge XR 《Cell research》2002,12(1):47-54
INTRODUCTIONLung cancer remains the leading cause of can-cer mortaIity in the world, accounting for more thanone sixth of cancer deaths in the world[1]. Antibod-ies have been proved to be a powerful tool fOr thestudy of 1ung cancer. A monoclonal IgM antibody,LC-1, was obtained in our laboratory. It can reactat a high rate with all four pathological types of lungcancers, including lung adenocarcinoma, 1ung squamous carcinoma, large cell lung cancer and smaIlcell lung cancert but not wit…  相似文献   
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Genetic differentiations and phylogeographical patterns of small organisms may be shaped by spatial isolation, environmental gradients, and gene flow. However, knowledge about genetic differentiation of rotifers at the intercontinental scale is still limited. Polyarthra dolichoptera and P. vulgaris are cosmopolitan rotifers that are tolerant to environmental changes, offering an excellent model to address the research gap. Here, we investigated the populations in Southeastern China and eastern North America and evaluated the phylogeographical patterns from their geographical range sizes, geographic–genetic distance relationships and their responses to spatial‐environmental factors. Using the mitochondrial cytochrome c oxidase subunit I gene as the DNA marker, we analyzed a total of 170 individuals. Our results showed that some putative cryptic species, also known as entities were widely distributed, but most of them were limited to single areas. The divergence of P. dolichoptera and P. vulgaris indicated that gene flow between continents was limited while that within each continent was stronger. Oceanographic barriers do affect the phylogeographic pattern of rotifers in continental waters and serve to maintain genetic diversity in nature. The genetic distance of P. dolichoptera and P. vulgaris populations showed significant positive correlation with geographic distance. This might be due to the combined effects of habitat heterogeneity, long‐distance colonization, and oceanographic barriers. Furthermore, at the intercontinental scale, spatial distance had a stronger influence than environmental variables on the genetic differentiations of both populations. Wind‐ and animal‐mediated transport and even historical events of continental plate tectonics are potential factors for phylogeography of cosmopolitan rotifers.  相似文献   
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Tumor acidic microenvironment is the main feature of many solid tumors.As a part of the tumor microenvironment,it has a profound impact on the occurrence and de...  相似文献   
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Although cisplatin is one of the chemotherapeutics most frequently used in oral squamous cell carcinoma (OSCC) treatment,it exerts multiple side effects and poo...  相似文献   
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