Determination of five kinds of trace ginkgolic acids in diterpene ginkgolides meglumine injection materials by LC-MS/MS Study on limit detection of flavones in diterpene ginkgolides meglumine injection materials by LC-MS and HPLC-DAD Phase III clinical trial of Diterpene Ginkgolides Meglumine Injection for syndrome of stagnant phlegm blocking collaterals in convalescence of atherosclerotic thrombotic cerebral infarction