Kolb H Simple Anatomy of the Retina. 2005 May 01 [updated 2012 Jan 31]. In: Kolb H, Fernandez E, Nelson R, editors. Webvision: The Organization of the Retina and Visual System [Internet]. Salt Lake City (UT): University of Utah Health Sciences Center; 1995-. Available from http://www.ncbi.nlm.nih.gov/books/NBK11533/
Numazaki M, Tominaga M Nociception and TRP Channels. Curr Drug Targets CNS Neurol Disord. 2004 Dec;3(6):479-85. Review.
Stockman A, Sharpe LT, Fach C The spectral sensitivity of the human short-wavelength sensitive cones derived from thresholds and color matches. Vision Res. 1999 Aug;39(17):2901-27.
Wakabayashi K, Gieser J, Sieving PA Aspartate separation of the scotopic threshold response (STR) from the photoreceptor a-wave of the cat and monkey ERG. Invest Ophthalmol Vis Sci. 1988 Nov;29(11):1615-22.
White JP, Urban L, Nagy I TRPV1 function in health and disease. Curr Pharm Biotechnol. 2011 Jan 1;12(1):130-44. 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.
