Fogarty A, Britton J The role of diet in the aetiology of asthma. Clin Exp Allergy. 2000 May;30(5):615-27. Review. Erratum in: Clin Exp Allergy 2000 Sep;30(9):1334.
Gazák R, Walterová D, Kren V Silybin and silymarin--new and emerging applications in medicine. Curr Med Chem. 2007;14(3):315-38. Review.
Hatch GE Asthma, inhaled oxidants, and dietary antioxidants. Am J Clin Nutr. 1995 Mar;61(3 Suppl):625S-630S. Review.
Miedema I, Feskens EJ, Heederik D, Kromhout D Dietary determinants of long-term incidence of chronic nonspecific lung diseases. The Zutphen Study. Am J Epidemiol. 1993 Jul 1;138(1):37-45.
Nelson SK, Bose SK, Grunwald GK, Myhill P, McCord JM The induction of human superoxide dismutase and catalase in vivo: a fundamentally new approach to antioxidant therapy. Free Radic Biol Med. 2006 Jan 15;40(2):341-7.
Roberts LJ, Morrow JD Measurement of F(2)-isoprostanes as an index of oxidative stress in vivo. Free Radic Biol Med. 2000 Feb 15;28(4):505-13. Review.
Wen Z, Dumas TE, Schrieber SJ, Hawke RL, Fried MW, Smith PC Pharmacokinetics and metabolic profile of free, conjugated, and total silymarin flavonolignans in human plasma after oral administration of milk thistle extract. Drug Metab Dispos. 2008 Jan;36(1):65-72. Epub 2007 Oct 3.
Weyhenmeyer R, Mascher H, Birkmayer J Study on dose-linearity of the pharmacokinetics of silibinin diastereomers using a new stereospecific assay. Int J Clin Pharmacol Ther Toxicol. 1992 Apr;30(4):134-8.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.