If pressure from outside the lungs causes atelectasis, your doctor will treat the cause of the pressure. For example, if the cause is a tumor or fluid buildup, your doctor will remove the tumor or fluid. This will allow your lung to fully expand. Atelectasis Caused by a Blockage
Pilus. Definition. noun, plural: pili. (microbiology) Short, filamentous projection on a bacterial cell, used not for motility but for adhering to other bacterial cell (especially for mating) or to animal cells. Supplement. Bacterial pili are involved in cell adhesion.
Bacteria possessing pili include Neisseria gonorrhoeae and some strains of Escherichia coli, Salmonella and Shigella species. Fimbriae (pili) are shorter, straighter and more numerous than bacterial flagella and are composed by subunits of protein called pilin. Example: Mutants of Neisseria gonorrhoeae that do not form pili are nonpathogen. 2  Sex pili (conjugation tube): It is a specialized kind of pili that forms the attachment between male (donor) and the female (recipient) bacteria during conjugation and acts as a conduit for the passage of DNA.