Hsieh CS, Ko CY, Chen SY, Liu TM, Wu JS, Hu CH, Sun CK. In vivo long-term continuous observation of gene expression in zebrafish embryo nerve systems by using harmonic generation microscopy and morphant technology. J Biomed Opt. 2008 Nov-Dec;13(6):064041.

http://www.ncbi.nlm.nih.gov/pubmed/19123687

“Optical higher-HGM can continuously observe zebrafish embryos, including cell morphology of the nervous system, for over 20 h with no photodamage effects, making it ideal for morphant technology research”