Linked Life Data

1970222

Source:http://linkedlifedata.com/resource/pubmed/id/1970222

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1990-5-11
pubmed:abstractText
The use of arbitrarily predefined time intervals during the circadian cycle is common practice in 24-h studies of gastric acidity. To determine whether slight displacements of a given time interval can be responsible for relevant changes in the acidity indexes calculated from pH profiles, we analyzed pH frequency distributions, and individual median and mean pH levels in three different, commonly adopted nocturnal time windows related to 132 curves obtained with single bedtime (10 PM) doses of various H2-antagonists. The time period 12 PM-8 AM has significantly less acid values (p less than 0.001) than the other two (10 PM-6 AM and 8 PM-8 AM), and therefore identifies the drugs' actions more closely. The individual median pH levels describe the H2-antagonist effect in 93% of profiles in the former time segment, whereas the percentage of accuracy is significantly lower (p less than 0.01) in both remaining periods (73% and 67%, respectively). The corresponding percentages of the individual mean pH levels are similar, even though their decline is less evident in the 10 PM-6 AM and 8 PM-8 AM time intervals. Our findings suggest that 1) slight shiftings of arbitrarily predefined time segments are associated with relevant fluctuations of acidity indexes and, therefore, should be standardized whenever possible, in order to favor international comparisons of results; 2) time intervals should be set to fit in as closely as possible with the drug-induced alkalinization wave; 3) pH frequency distribution should always be calculated and taken into careful consideration.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0002-9270
pubmed:author
pubmed:issnType
Print
pubmed:volume
85
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
381-4
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
24-hour gastric pH-metry analysis: influence of arbitrarily predefined time intervals on the reliability of acidity indexes.
pubmed:affiliation
Cattedra di Clinica Medica R, Università di Genova, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't