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排序方式: 共有223条查询结果,搜索用时 18 毫秒
221.
Gilbert MT Tomsho LP Rendulic S Packard M Drautz DI Sher A Tikhonov A Dalén L Kuznetsova T Kosintsev P Campos PF Higham T Collins MJ Wilson AS Shidlovskiy F Buigues B Ericson PG Germonpré M Götherström A Iacumin P Nikolaev V Nowak-Kemp M Willerslev E Knight JR Irzyk GP Perbost CS Fredrikson KM Harkins TT Sheridan S Miller W Schuster SC 《Science (New York, N.Y.)》2007,317(5846):1927-1930
Although the application of sequencing-by-synthesis techniques to DNA extracted from bones has revolutionized the study of ancient DNA, it has been plagued by large fractions of contaminating environmental DNA. The genetic analyses of hair shafts could be a solution: We present 10 previously unexamined Siberian mammoth (Mammuthus primigenius) mitochondrial genomes, sequenced with up to 48-fold coverage. The observed levels of damage-derived sequencing errors were lower than those observed in previously published frozen bone samples, even though one of the specimens was >50,000 14C years old and another had been stored for 200 years at room temperature. The method therefore sets the stage for molecular-genetic analysis of museum collections. 相似文献
222.
Asara et al. (Reports, 13 April 2007, p. 280) reported sequencing of Tyrannosaurus rex proteins and used them to establish the evolutionary relationships between birds and dinosaurs. We argue that the reported T. rex peptides may represent statistical artifacts and call for complete data release to enable experimental and computational verification of their findings. 相似文献
223.
Sergey A. Dyshlovoy Larisa K. Shubina Tatyana N. Makarieva Alla G. Guzii Jessica Hauschild Nadja Strewinsky Dmitrii V. Berdyshev Ekaterina K. Kudryashova Alexander S. Menshov Roman S. Popov Pavel S. Dmitrenok Markus Graefen Carsten Bokemeyer Gunhild von Amsberg 《Marine drugs》2022,20(12)
Two new guanidine alkaloids, batzelladines O (1) and P (2), were isolated from the deep-water marine sponge Monanchora pulchra. The structures of these metabolites were determined by NMR spectroscopy, mass spectrometry, and ECD. The isolated compounds exhibited cytotoxic activity in human prostate cancer cells PC3, PC3-DR, and 22Rv1 at low micromolar concentrations and inhibited colony formation and survival of the cancer cells. Batzelladines O (1) and P (2) induced apoptosis, which was detected by Western blotting as caspase-3 and PARP cleavage. Additionally, induction of pro-survival autophagy indicated as upregulation of LC3B-II and suppression of mTOR was observed in the treated cells. In line with this, the combination with autophagy inhibitor 3-methyladenine synergistically increased the cytotoxic activity of batzelladines O (1) and P (2). Both compounds were equally active in docetaxel-sensitive and docetaxel-resistant prostate cancer cells, despite exhibiting a slight p-glycoprotein substrate-like activity. In combination with docetaxel, an additive effect was observed. In conclusion, the isolated new guanidine alkaloids are promising drug candidates for the treatment of taxane-resistant prostate cancer. 相似文献