{'fraction_non_alphanumeric': 0.010638297872340425, 'fraction_numerical': 0.004728132387706856, 'mean_word_length': 5.565891472868217, '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}}
Alterations in the kinetics of hemagglutinin formation following embryonic bursectomy.


 Surgical removal of the bursa of Fabricius 2 days before hatching caused a significant decrease in the number of cells capable of rosette formation and in the amount of antibody produced to sheep erythrocytes. This was accompanied by an alteration in the kinetics of the response and production of predominantly 2-mercaptoethanol sensitive, high molecular weight antibody. Bursectomy at 19 days of incubation appears selectively to eliminate a population of immunologically active cells. The remaining immunocompetent cells are incapable of developing a normal antibody response to sheep erythrocytes, perhaps because of a decreased population size and/or a derangement in the normal homeostatic mechanism responsible for the control of antibody synthesis.