Site of deposition of tracer aerosol Molecular weight of solute probe

Airway caliber Lung capacity Mucus/cilia interaction Mucosal surface damage Spontaneous cough Exercise Disease Drugs

Particle size of aerosol

Pattern of inhalation

Site of deposition of labeled solute Recirculation of labeled solute Stability of labeled solute in vivo Ventilation


Apex-base gradient in LEP

Inspiratory volume PEEP CPAP Exercise Smoking have a marked effect on MCC. In addition, inter- and intrasubject variability in deposition makes it difficult to do repeated measurements of MCC and to group subjects. The differences between subjects can be partly attributed to airway geometry and lung size [129]; therefore, measurements of lung volumes and expiratory flowrates should be obtained for each subject studied.

Submicronic aerosols of low molecular weight solutes are used to measure epithelial permeability [25,26]; the site of deposition of these tracers must be distal to the ciliated airway surfaces. LEP is measured by dynamic planar imaging of the lung for 15-30 minutes. Parallel blood samples can be obtained at the same time points to measure plasma radioactivity, but this is not critical to the determination of the rate of absorption of the radiotracer. MCC of the submicronic aerosol is extremely slow, with t1/2 in excess of 24hours. Because LEP is measured over 30 min, the error due to MCC is negligible. Peripheral lung regions of interest are usually chosen for analysis of uptake to avoid the contribution from any radioactivity deposited in the hilar regions [130].

Inhalation of hypertonic saline is a noninvasive diagnostic test using nonradioactive aerosols and results in expectoration of sputum. The cellular content of the sputum, related to the degree of inflammation present in the lung in asthma, is then measured using specific laboratory techniques and provides an objective means of monitoring the disease and the effectiveness of anti-inflammatory therapy. Scheduling of these tests, either pre- or postinhalation of the tracer aerosol, would be determined by the clinical question or the research objective.

Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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