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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
|
pubmed:dateCreated |
1995-5-4
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pubmed:abstractText |
The deposition of 11C-nicotine in the respiratory tract from a nicotine vapor inhaler was studied by means of positron emission tomography (PET) in an intrasubject comparison of six healthy smokers using two modes of inhalation: one with shallow, frequent inhalations ("buccal mode") and one with deep inhalations ("pulmonary mode"). An average of 15% of the radioactivity was released from the vapor inhaler after 5 minutes of inhalation. Approximately 45% of the dose released was found in the oral cavity. A significant amount of radioactivity, 10%, was observed in the esophagus, suggesting transfer of a major fraction of the dose to the stomach. Only a minor fraction, 5%, was found in the lungs, followed by 2% in the bronchi and 1% in the trachea. The deposition in the oral cavity closely followed a linear pattern during the 5 minutes of inhalation and was followed by a rapid elimination from the oral cavity, with an average half-life of 18 minutes. Only 8% of the dose released remained in the oral cavity 45 minutes after the end of inhalation. On the other hand, the dose fraction of about 14% distributed into the body tissue compartment at the end of inhalation had risen to 60% at that late time point. No statistically or clinically important differences were observed between the buccal and the pulmonary mode of inhalation in either deposition pattern or elimination rates.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
AIM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Mar
|
pubmed:issn |
0009-9236
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pubmed:author | |
pubmed:issnType |
Print
|
pubmed:volume |
57
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pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
309-17
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:7697948-Administration, Inhalation,
pubmed-meshheading:7697948-Adult,
pubmed-meshheading:7697948-Carbon Radioisotopes,
pubmed-meshheading:7697948-Humans,
pubmed-meshheading:7697948-Male,
pubmed-meshheading:7697948-Middle Aged,
pubmed-meshheading:7697948-Mouth,
pubmed-meshheading:7697948-Nebulizers and Vaporizers,
pubmed-meshheading:7697948-Nicotine,
pubmed-meshheading:7697948-Respiratory System,
pubmed-meshheading:7697948-Tomography, Emission-Computed
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pubmed:year |
1995
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pubmed:articleTitle |
Regional deposition of inhaled 11C-nicotine vapor in the human airway as visualized by positron emission tomography.
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pubmed:affiliation |
Uppsala University PET Center, UAS, Sweden.
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pubmed:publicationType |
Journal Article,
Comparative Study,
Research Support, Non-U.S. Gov't
|