某些病毒的核衣壳是由被膜所包绕.In some viruses the nucleocapsid is surrounded by an envelope.衣壳同包围它的核酸一起称为核衣壳.The capsid together with the enclosed nucleic acid is the nucleocapsid.其核酸结构为线状双股DNA, 衣壳为二十面体对称,有囊膜.It has linear double stra...
抬起一只脚，弯曲脚趾，使脚尖朝下。Raise one foot, curl the toes and point the foot down-wards.她弯腰向下,左右手交叉触及脚趾.She reached down, touching her toes with opposite hands.我双腿麻木，脚趾疼痛。My legs felt numb and my toes ached....
这个角的正确量度是30°10′.The exact measurement of this angle is 30 degrees 10 minutes.湿度是空气内含水分多少的量度.Humidity is a measure of moisture in the atmosphere.发射强度和辐照强度只有对一定表面上通量的量度才是有意义的.Emittance and irradiance are meaningful measure...