The paper discusses the fundamental causes of surplus management from the visual angle of contract theories and information asymmetry theories, and analyzes the internal mechanism of contract frictions and blocked communication to produce surplus management.

Effects of dexamethasone and/or fentanyl on interscalene brachial plexus block;

Prevention of Brachial Plexus Intermuscular Groove Block Induced Cardiovascular Adverse Effects by Intravenous Penehyclidine Hydrochloride Injection;

Postgraduate :MA Song_he Teacher: professor Yan Xiang_MoObjective:To study of influence factor for curative effect of sciatica by posas compartment block using thermography ,CT guide fixe puncture point ,depth of puncture needle ,inject anethetic drugs, go further into interrelated factor for treatment curative sciatica by psoas compartment block.