{'fraction_non_alphanumeric': 0.02035928143712575, 'fraction_numerical': 0.0, 'mean_word_length': 6.145299145299146, '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}}
[Function and pathology of bone marrow stromal cells].

For their lineage commitment and differentiation haematopoietic tem cells need a specific microenvironment. This milieu is formed by bone marrow stroma, which includes lymphocytes, macrophages, fibroblasts, reticular cells, adipocytes, osteogenic and endothelial cells. These cells play different regulatory roles in supporting haemopoiesis. The stroma-stem cell interaction take place by immediate cellular contact. Growth factors and extracellular matrix molecules produced by stromal cells influence the regulation of haemopoiesis as well. This cellular context could be established in different animal models. Impairment of stromal cell function with increased fibroblast proliferation and increased collagen synthesis is an impressive morphological feature of myelofibrosis.