BACKGROUND AND AIMS The extant species of the seed plant group Gnetales (Ephedra, Gnetum and Welwitschia) have been considered a remnant of a much greater, now extinct, diversity due to the pronounced differences in form and ecology among the genera. Until recently, this hypothesis has not been supported by evidence from the fossil record. This paper adds to the expanding information on Gnetale...

The Qinghai-Tibetan Plateau (QTP) has become one of the hotspots for phylogeographical studies due to its high species diversity. However, most previous studies have focused on the effects of the Quaternary glaciations on phylogeographical structures and the locations of glacial refugia, and little is known about the effects of the aridization of interior Asia on plant population structure and ...

used in Chinese and Japanese traditional (Kampo) medicines. Although about 35 species belonging to the genus Ephedra are distributed in Eurasia, North America, and South America, only a few species contain pharmacologically active ephedrine alkaloids and are used for medicinal purposes. The Japanese Pharmacopoeia defines Ephedra Herb as dried aerial parts of Ephedra sinica, E. intermedia and E....

CONTEXT Ephedra and ephedrine sometimes are used for weight loss or enhanced athletic performance, but the efficacy and safety of these compounds are uncertain. OBJECTIVE To assess the efficacy and safety of ephedra and ephedrine used for weight loss and enhanced athletic performance. DATA SOURCES We searched 9 databases using the terms ephedra, ephedrine, adverse effect, side effect, effic...