[1] Nicotine Research Center,
[2] Mayo Clinic and Mayo Foundation,undefined
[3] Rochester,undefined
[4] MN 55905,undefined
[5] USA,undefined
[6] Division of General Internal Medicine,undefined
[7] Mayo Clinic and Mayo Foundation,undefined
[8] Rochester,undefined
[9] MN 55905,undefined
[10] USA,undefined
[11] Section of Biostatistics,undefined
[12] Mayo Clinic and Mayo Foundation,undefined
[13] Rochester,undefined
[14] MN 55905,undefined
[15] USA,undefined
[16] Laboratory Medicine and Pathology,undefined
[17] Mayo Clinic and Mayo Foundation,undefined
[18] Rochester,undefined
[19] MN 55905,undefined
[20] USA,undefined
[21] Mayo Clinic,undefined
[22] 200 First Street,undefined
[23] SW,undefined
[24] Rochester,undefined
[25] MN 55905,undefined
[26] USA e-mail: rhurt@mayo.edu,undefined
[27] Fax: +1-507-266-7900,undefined