Decreased Striatal Vesicular Monoamine Transporter Type 2 Correlates With the Nonmotor Symptoms in Parkinson DiseaseShi, Xinchong; Zhang, Yan; Xu, Shaohua; Kung, Hank F.; Qiao, Hongwen; Jiang, LuLu; Zhu, Lin; Guo, Qiyi; Yi, Chang; Luo, Ganhua; Wu, Lei; Pei, Zhong; Wang, Jian; Zhang, Xiangsong; Chen, Ling · Clinical Nuclear Medicine · 2019