PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “motor function”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 973 records · Page 54Linked to original sources
PubMed1983

Motor function of the opossum sphincter of Oddi.

We studied the opossum sphincter of Oddi (SO) because in this species the SO is approximately 3 cm in length and its extraduodenal location permits recording of motor activity with negligible interference from duodenal motor activity. The SO segment of 120 animals was evaluated by one or more of the following: (a) intraluminal manometry; (b) electromyography; (c) common bile duct (CBD) flow monitored by a drop counter; (d) cineradiography of intraductal contrast medium; and (e) histologic examination. SO pull-throughs using an infused catheter of 0.6-mm o.d. invariably showed a high pressure zone (HPZ) of 18 +/- 3 SE mm Hg in the terminal 4-5 mm of the SO segment. This HPZ had a narrow lumen, 0.5-0.7 mm in diam, and prominent circular muscle. The HPZ in the terminal SO had both active and passive components. HPZ with minimal amplitude and a paucity of underlying smooth muscle were present inconstantly at the junction of the SO segment with the CBD and pancreatic duct, respectively. The dominant feature of the SO segment was rhythmic peristaltic contractions that originated in the proximal SO and propagated toward the duodenum. These contractions occurred spontaneously at a rate of 2-8/min, ranged up to 200 mm Hg in magnitude, had a duration of approximately 5 s and were not abolished by tetrodotoxin. Concurrent myoelectric and manometric recordings showed that each phasic contraction was immediately preceded by an electrical spike burst. Simultaneous recordings of cineradiography, CBD inflow of contrast medium, SO manometry, and SO electromyography indicated that rhythmic peristaltic contractions stripped contrast medium from the SO into the duodenum. During SO systole, CBD emptying was transiently interrupted, whereas SO filling occurred during the diastolic interval between SO peristaltic contractions. SO distention increased the frequency of SO peristalsis. We conclude that (a) the dominant feature of the opossum SO is rhythmic peristaltic contractions that originate in the proximal SO and propagate toward the duodenum; (b) these forceful SO peristaltic contractions are myogenic in origin and serve as a peristaltic pump that actively empties the SO segment; (c) CBD outflow occurs passively during SO diastole, but is interrupted transiently during each SO peristaltic contraction; and (d) a short HPZ with active as well as passive components exists in the distal SO segment and acts as a variable resistor to SO outflow.

Ampulla of Vater↗
PubMed2001

Electrophysiological studies and physical examinations in entrapment neuropathy: sensory and motor functions compensation for the central nervous system in cases with peripheral nerve damage.

We performed electrophysiological studies and objective physical examinations in 60 patients with carpal tunnel syndrome and 21 patients with cubital tunnel syndrome. Compared with our normal data, the sensory nerve conduction velocity across the wrist was defined as abnormal in 97% of the carpal tunnel syndrome patients, the corresponding value of the amplitude of the sensory nerve action potential was 58% and the value of the two point discrimination test was 28% while the value of the Semmes-Weinstein monofilament test was defined as abnormal in 64% of the cases. In cubital tunnel syndrome patients, motor nerve conduction velocity across the elbow was defined as abnormal in 91%, the amplitude of the M-wave was 96%, manual muscle testing was 63% and their side pinch strength was defined as abnormal in 24% of the cases. The functions of recognition are preserved in the cases with moderate damage of peripheral nerve due to the cancellation of synaptic occlusion. Motor performance also compensated in the central nervous system. Therefore the sensitivity of the objective physical examination is less than that of electrophysiological study of peripheral nerve itself. For entrapment neuropathy electrophysiological findings are more sensitive than the objective physical examinations.

Adolescent↗
PubMed2003

Transplantation of motoneuron-enriched neural cells derived from mouse embryonic stem cells improves motor function of hemiplegic mice.

Embryonic stem (ES) cells are expected to be a potential donor source for neural transplantation. We have obtained motoneuron-enriched neural progenitor cells by culturing mouse ES cells with retinoic acid (RA). The cells also expressed mRNA of a neurotrophic factor, neurotrophin-3 (NT-3). The left motor cortex area of mice was damaged by cryogenic brain injury, and the neural cells were transplanted underneath the injured motor cortex, neighboring to the paraventricular region. We found that the cells expressing neuronal phenotypes not only remained close to the implantation site, but also exhibited substantial migration penetrating into the damaged lesion, in a seemingly directed manner up to cortical region. We found that some of the neural cells differentiated into Islet1-positive motoneurons. It seems likely that the ability of the ES cell-derived neural progenitor cells to respond in vivo to guidance cues and signals that can direct their migration and differentiation may contribute to functional recovery of the recipient mice. We found that an "island of the mature neuronal cells" of recipient origin emerged in the damaged motor cortex. This may be associated with the neuroprotective effects of the ES cell-derived neural cells. The ES cells differentiated into CD31+ vasculoendothelial cells with the RA treatment in vitro. Furthermore, the grafted cells may provide sufficient neurotrophic factors such as NT-3 for neuroprotection and regeneration. The grafted neural cells that migrated into residual cortex and differentiated into neurons had purposefully elongated axons that were stained with anti-neurofilament middle chain (NFM) antibody. Our study suggests that motoneurons can be induced from ES cells, and ES cells become virtually an unlimited source of cells for experimental and clinical neural cell transplantation.

Animals↗
PubMed1995

Myosin motor function: structural and mutagenic approaches.

Recent advances in three areas of myosin research--structural biology, in vitro motility assays, and mutagenesis--are leading to a new understanding of the molecular mechanism of chemomechanical transduction by this motor protein. Highlights include rational design of mutants using the crystal structure of subfragment 1, combined in vivo and in vitro mutant analyses using Dictyostelium, and the emergence of baculovirus as an in vitro system for expression of mutated mammalian myosins.

Animals↗
PubMed1992

[Hypotrypsinemia as a possible factor in the activation of motor function of the duodenum in pancreatic atrophy in rats].

The effect of pancreas atrophy on myoelectrical activity of the duodenum and serum trypsin, trypsin inhibitor, amylase, lipase activity has been described. The activation of the duodenum motor activity has been established. The changes in the motor activity were connected with trypsin and trypsin inhibitor activity of serum. The motor activity changes were compensated by trypsin therapy.

Amylases↗
PubMed1985

[Effect of hyperbaric oxygenation on the recovery of motor functions in vertebrogenic myelopathies].

The use of hyperbaric oxygenation (HBO) in the treatment of vertebrogenic ischemic myelopathies makes it possible not only to arrest the progression of the disease but also to achieve stable regress of motor disturbances in a relatively short period, which helps to reduce the time of treatment and hospitalization. In lateral amyotrophic sclerosis HBO therapy produces a minimum and short positive effect only in some patients. In most cases the therapy failed to control or stabilize neurological disorders. Clinical data are confirmed by dynamic electromyographic studies. The results obtained make it possible to recommend HBO in a complex of therapeutic measures in cases of vascular damage to the spinal cord.

Adult↗