PubMed Health⌕ Search

Biomedical subjects

A Jasinski

Publications and source records attributed to A Jasinski.

6 recordsLinked to original sources
PubMed2005

Simultaneous functional magnetic resonance imaging in the rat spinal cord and brain.

Functional magnetic resonance imaging (fMRI) method was developed to investigate the pattern and temporal relationship in neuronal pathways of brain and spinal cord. Signal intensity changes correlating with stimulation patterns were observed simultaneously in the rat spinal cord and brain using fMRI at 9.4 T. Electrical stimulation of the forepaw was used to elicit activity. A quadrature volume RF coil covering both brain and the cervical spinal cord was used. Sets of fast spin echo (FSE) images were acquire simultaneously for both brain and spinal cord fMRI. Experiments were repeated in single animal and across animals. Activities within the dorsal horn of the spinal cord and within the somatosensory cortex were observed consistently within each animal as well as across animals.

Animals↗
PubMed1992

Shielded gradient coils and radio frequency probes for high-resolution imaging of rat brains.

A shielded gradient system and radio frequency probes for a 4.7-T/30-cm horizontal bore magnet are described. The systems were designed principally to obtain images and localized spectra from rat brains. The gradients can operate in either a shielded or non-shielded mode. The rf probe, which combines both highest sensitivity and highest resolution, consists of a large modified saddle type transmitter and a small surface reception coil, actively decoupled using diodes. The system performance is demonstrated on phantoms and on a rat brain, where an image with in plane resolution of 80 microns and a slice thickness of 150 microns is obtained.

Animals↗
PubMed1991

Hexagonal surface gradient coil for localized MRS of the heart.

A surface gradient coil designed to obtain localized magnetic resonance spectroscopy of the heart in vivo is described. Images and 31P spectra from phantoms and both pig and dog hearts in vivo are shown. The coil was used in conjunction with a rf surface coil to obtain 31P spectra from transmural sections of the left ventricular wall of a dog heart in vivo to demonstrate differences between normal and ischemic tissue.

Animals↗
PubMed1990

Double EPI sequence with 180 degrees RF pulses.

Rapid imaging can be performed in the magnetic field of low homogeneity using 180 degrees RF pulses instead of gradient reversals to form a series of differently phase-encoded echoes. A modified version of pi-pulsed EPI which samples the data in two complementary shots was designed. Its advantage for objects of short T2 is illustrated by phantom images.

Fourier Analysis↗
PubMed1966

Rate of movement and redistribution of stainable neurosecretory granules in hypothalamic neurons.

Electrical stimulation of the olfactory tract of goldfish for one minute can deplete completely the stainable neurosecretory granules from cells of the preoptic nucleus as well as from their axons. Thus, in stimulated neurons secretory granules appear to move toward the neurohemal point of discharge at a rate of about 2 millimeters per minuite. Reaccumutlation of neurosecretory granules in depleted neurons to approximately normal numbers requires about 1 to 1.5 hours. Histological evidence indicates that, during the period of reaccumulation, granules move out of the perikaryon until normal granulation in the axons is achieved; finally, granulation of the perikaryon is restored.

Animals↗