However, the age stipulation is new and surprising, says David Penson, MD, associate professor of urology and preventive medicine at the Keck School of Medicine, University of Southern California.

• 然而，对年龄的规定是新出现的，这是令人吃惊的，DavidPenson博士说。他是南加利福尼亚大学Keck医学院泌尿外科及预防医学的副教授。