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Biomedical subjects

J A Lohman

Publications and source records attributed to J A Lohman.

5 recordsLinked to original sources
PubMed1988

Prospects for NMR imaging in the study of biological morphogenesis.

Small objects can be visualised with a spatial resolution that approaches microscopic dimensions using the technique of high resolution nuclear magnetic resonance (NMR) imaging. Some important features of the method are described and the prospects for using the technique to study morphogenesis are discussed. It is concluded that NMR imaging, in conjunction with the related method of localised spectroscopy, is capable of producing novel structural information.

Animals↗
PubMed1988

Surface coil localization of 31P NMR signals from orthotopic human kidney and liver.

By incorporating the hyperbolic secant inversion pulses with the image-selected in vivo spectroscopy localization technique and by applying a gradient-echo imaging method, we have selected only the 31P NMR signals from orthotopic human kidney and liver, using a single concentric 1H/31P surface coil. Corresponding to the experimental results on animal studies, the phosphocreatine signal is dramatically reduced in the localized spectra. Our localization strategy also allows us to shim easily on the well-defined volume of interest and leads to high-resolution spectra that exhibit multiplet structure. Our results indicate that we can obtain localized signals from deep small organs and point the way for other human metabolism studies.

Humans↗
PubMed1987

Spin echo imaging of multiple chemical shifts.

A method to obtain separate cross-sectional NMR images of chemically different species on the basis of their difference in chemical shift is presented. The total experiment time is no longer than that required for a conventional image and the method retains the full sensitivity of a spin-echo 2DFT imaging experiment. Simple addition of the chemical-shift selective images produces an image free from chemical-shift artifacts. Results of an in vivo experiment on a human subject are presented.

Body Water↗
PubMed1987

Natural abundance 13C NMR spectrum of glycogen in humans.

In vivo NMR has focused on using 31P and 1H to study metabolism in humans. Comparable 13C NMR studies have not been undertaken, presumably, because of its insensitivity. We report herein that the natural abundance 13C signal from C1 glycogen is observable. The ability to observe the signal opens new opportunities to noninvasively study glycogen metabolism in man.

Humans↗