[1] Reference Laboratory,
[2] National Institute of Occupational Health,undefined
[3] Lersø Parkallé 105,undefined
[4] DK-2100 Copenhagen,undefined
[5] Denmark e-mail: lbo@ami.dk,undefined
[6] Tel.: +45-39-165200,undefined
[7] Fax: +45-39-165201,undefined
[8] Department of Dermatology,undefined
[9] Gentofte Hospital,undefined
[10] University of Copenhagen,undefined
[11] Niels Andersens Vej 65,undefined
[12] DK-2900 Hellerup,undefined
[13] Denmark,undefined
[14] National University Hospital,undefined
[15] Laboratory of Medical Allergology,undefined
[16] Allergy Unit,undefined
[17] TA 7542,undefined
[18] Tagensvej 20,undefined
[19] DK-2200 Copenhagen,undefined
[20] Denmark,undefined