{'fraction_non_alphanumeric': 0.0249003984063745, 'fraction_numerical': 0.036852589641434265, 'mean_word_length': 4.742857142857143, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Twenty-five years of fluorescein angiography.

The history from fluorescence to fluorescein angiography to the present spans more than 130 years. From the original observation of fluorescence by Sir J. Herschell and Sir D. Brewster in about 1850 to the development of fluorescein angiography by Flocks and co-workers in 1958 to present-day techniques for humans by Alvis and Novotny in 1960, we have enjoyed a wealth of information provided by fluorescein angiography. See also pp 1269, 1303, and 1307. Sir J. Herschell and Sir D. Brewster first noted the fluorescence of fluorite, a crystal commonly known as calcium fluoride . This phenomenon was extensively investigated and reported in 1852 by Sir G. G. Stokes, 1 resulting in Stokes' Law. In essence, this law states that fluorescence is light emitted from a substance only during excitation of a different source, usually of a shorter wavelength. In 1871, a German chemist named Adolf Baeryer 2 first synthesized fluorescein by combining resorcinol