Cipolla MJ, Williamson WK, Nehler ML, Taylor LM Jr, Porter JM The effect of elevated homocysteine levels on adrenergic vasoconstriction of human resistance arteries: the role of the endothelium and reactive oxygen species. J Vasc Surg. 2000 Apr;31(4):751-9.
Masser PA, Taylor LM Jr, Porter JM Importance of elevated plasma homocysteine levels as a risk factor for atherosclerosis. Ann Thorac Surg. 1994 Oct;58(4):1240-6. Review.
McLafferty RB, Moneta GL, Taylor LM Jr, Porter JM Ability of ankle-brachial index to detect lower-extremity atherosclerotic disease progression. Arch Surg. 1997 Aug;132(8):836-40; discussion 840-1.
Nehler MR, Moneta GL, Lee RW, Edwards JM, Taylor LM Jr, Porter JM Improving selection of patients with less than 60% asymptomatic internal carotid artery stenosis for follow-up carotid artery duplex scanning. J Vasc Surg. 1996 Oct;24(4):580-5; discussion 585-7.
Nehler MR, Taylor LM Jr, Porter JM Homocysteinemia as a risk factor for atherosclerosis: a review. Cardiovasc Surg. 1997 Dec;5(6):559-67. Review.
Taylor LM Jr, Moneta GL, Sexton GJ, Schuff RA, Porter JM Prospective blinded study of the relationship between plasma homocysteine and progression of symptomatic peripheral arterial disease. J Vasc Surg. 1999 Jan;29(1):8-19; discussion 19-21.
Taylor LM Jr, Porter JM Elevated plasma homocysteine as a risk factor for atherosclerosis. Semin Vasc Surg. 1993 Mar;6(1):36-45. Review.
Taylor LM Jr Elevated plasma homocysteine as risk factor for peripheral arterial disease--what is the evidence? Semin Vasc Surg. 2003 Sep;16(3):215-22. Review.
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.
