Preparation and physicochemical properties of three kinds of superfine powder of Chinese materia medica Study on decompression extraction of Sansheng Hehuan Decoction Study on co-processd excipient of microcrystalline cellulose and glycerol monostearate Study on pharmacognosy of Rubia cordifolia Study on characteristics and dissolution behavior in decoction for boiling powders of Chinese materia medica