Linked Life Data

6322223

Source:http://linkedlifedata.com/resource/pubmed/id/6322223

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1984-4-10
pubmed:abstractText
The frequency dependence of spin-lattice (T1) relaxation times of protons in tissues and other macromolecular solutions was investigated. This dependence can be principally assigned to reduced mobility of water molecules "hydrated" on the surface of macromolecular structures. The T1 relaxation time of "hydration water" was found to increase linearly with frequency in the range from 5 to 100 MHz (T1 = 1.83 f + 25.0). It is assumed that the remainder of water in the tissue has a relaxation rate that is independent of frequency, as is characteristic of bulk tap water. Variations occur in the fraction of water hydrated or bound from one organ to the next. As the observed relaxation rate is a weighted average of the two rates as described by the fast exchange model, the above empirical relationship can be used to take a tissue T1 relaxation time measured at one frequency and then calculate the tissue T1 relaxation time that would be expected at another frequency. Good agreements were obtained between such calculated tissue T1 values and the T1 values actually measured at the second frequency. Variations between the calculated and measured T1 values in some classes of tissues indicate that there are also less important secondary factors such as lipid content.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0033-8419
pubmed:author
pubmed:issnType
Print
pubmed:volume
151
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
135-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Frequency dependence of magnetic resonance spin-lattice relaxation of protons in biological materials.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.