Synthesis of Biscoumarin and Dihydropyran Derivatives and Evaluation of Their Antibacterial Activity.

In an attempt to find a new class antibacterial agents, a series of biscoumarins (1-4) and dihydropyrans (5-13) were successfully prepared. The molecular structures of four representative compounds, that is, 4, 5, 8 and 12 were confirmed by single crystal X-ray diffraction study. These synthesized compounds were screened for their antibacterial activity in vitro against Staphylococcus aureus (S.

Posterior rotating rod reduction strategy for irreducible atlantoaxial subluxations with congenital odontoid aplasia.

Study Design: Applying rotating rod techniques to reduce irreducible atlantoaxial dislocation.

Objective: To spare the occipital-C1 motion by the strategy in reduction of before surgery irreducible atlantoaxial dislocation with obvious neurologic symptoms and congenital odontoid aplasia.

Summary Of Background Data: The treatment of atlantoaxial dislocation (AAD) is a challenging problem for most surgeons.