| Concentration of protoporphyrin IX in cancer tissues and blood in patients with colorectal cancer at early stage. |
| All laboratories submitting results for erythrocyte protoporphyrin fractions found predominantly free protoporphyrin in the erythropoietic protoporphyria patient. |
| Four molecules of this porphyrin precursor cyclize and undergo several side-chain modifications to yield the tetrapyrrole protoporphyrin. |
| Although protoporphyrin was associated with a large proportion of our abnormal measurements, it was not found to be diagnostically useful. |
| Increased expression of the Abcg2 transporter during erythroid maturation plays a role in decreasing cellular protoporphyrin IX levels. |
