查一下 PD-1 http://www.onclive.com/conference-coverage/nyl-2013/PD-1-and-PD-L1-Inhibitors-Expected-to-Change-the-Landscape-of-Lung-Cancer-Treatment http://www.pmlive.com/pharma_news/mercks_anti-pd1_drug_promising_in_lung_cancer_507309