In vitro antitumor activities of the fractions of the petroleum ether extract primarily separated from Stellera Chamaejasmel L. By column chromatography on silica gel是什么意思_In vitro antitumor activities of the fractions of the petroleum ether extract primarily separated from Stellera Chamaejasmel L. By column chromatography on silica gel在线翻译_英语_读音_用法_例句