A photomultiplier can amplify the signal to detectable levels 光電倍增管可將此訊號放大到可偵測的程度。
In the families of babies who had detectable levels of nnal , family members reported smoking an average of 76 cigarettes per week 研究顯示,在那些尿液樣本中含有nnal的嬰兒的家庭中,家庭成員平均每周吸煙76支。
For babies who had no detectable levels of nnal in their urine , the average number of cigarettes reportedly smoked by family members was 27 per week 而那些尿液樣本中未發現nnal的嬰兒的家庭中,家庭成員平均每周吸煙27支。
Urine from nearly half of the infants contained detectable levels of nnal , a chemical byproduct produced in the human body when it processes nnk , a cancer - causing chemical , or carcinogen , found only in tobacco 在他們生活的家庭環境中,父母至少有一人是煙民。研究人員在將近一半的尿液樣本中發現了相當水平的nnal 。