6Wolfenbarger L L, Phifer P R.. The ecological risks and bene- fits of genetically engineered plants[J]. Science, 2000, 290 (5499): 2088-2093.
7Kuiper H A, Kleter G A, Noteborn H P, et al. Assessment of the food safety issues related to genetically modified foods[J]. The plant journal, 2001, 27(6): 503-528.
8Boholm A. Comparative studies of risk perception: a review of twenty years of research[J]. Journal of risk research, 1998, 1(2): 135-163.
9Pan Z, Kosicki G M. Framing analysis: An approach to news discourse[J]. Political communication, 1993, 10(1): 55-75.
10Goffman E. Frame analysis: An essay on the organization of experience[M]. Cambridge: Harvard University Press, 1974: 16--17.