In some embodiments of the present invention, the imaging agent comprises a radioactive label including, but not limited to 14 C, 36 Cl, 57 Co, 58 Co, 51 Cr, 125 I, 131 I, 111 Ln, 152 Eu, 59 Fe, 67 Ga, 32 P, 186 Re, 75 Se, Tc 99m, and 175 Yb cialis otc viagra iv atenolol In its statement, the...