No significant translocation of inhaled 35-nm carbon particles to the circulation in humans.

Human pulmonary retention of 35 nm 99mTc-labeled carbonaceous particles, produced with a modified Technegas generator, was followed for 24 h using a gamma camera imaging technique. Nine healthy subjects and four asthmatics inhaled the test particles. Particle labeling stability was tested in vitro during 48 h.

Long-term clearance from small airways in subjects with ciliary dysfunction.

The objective of this study was to investigate if long-term clearance from small airways is dependent on normal ciliary function. Six young adults with primary ciliary dyskinesia (PCD) inhaled 111 Indium labelled Teflon particles of 4.2 microm geometric and 6.

Long-term clearance from small airways in patients with chronic bronchitis: experimental and theoretical data.

Long-term clearance (21 days) from small airways was studied in 9 patients with chronic bronchitis (CB), 65 +/- 10 (mean +/- SD) years, and was compared to 15 age-matched healthy subjects of 67 +/- 7 (mean +/- SD) years. Six of the CB patients were studied twice. All subjects inhaled monodisperse 6 microm Teflon particles labelled with 111In with an extremely slow inhalation flow, 0.