Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.

Ex Input:
Abstract: Symptomatic assessment and oesophageal investigations were done in 25 consecutive patients with the irritable bowel syndrome attending a gastroenterological clinic. Symptoms of gastro-oesophageal reflux, dysphagia, and a globus sensation were significantly commoner than in a control group of fracture clinic patients. Ambulatory oesophageal pH monitoring showed clearly abnormal reflux in 11 of 22 patients (50%). Nine patients had macroscopic endoscopic changes and a further 11 biopsy changes alone, of oesophagitis which was thus present in 80% overall. Lower oesophageal sphincter pressure was significantly less in irritable bowel patients than in age and sex matched controls, but upper oesophageal sphincter pressure was comparable in the two groups and disordered peristalsis was not found. Oesophageal symptoms in the irritable bowel syndrome are mainly caused by gastro-oesophageal reflux predisposed to by a subnormal lower oesophageal sphincter pressure, rather than by oesophageal spasm.

Ex Output:
Adult

Ex Input:
Abstract: Brain topography may have its earliest expression as spatial gradients of molecules controlling the deposition of neurones and neuronal processes. In the vertebrate visual system there is evidence that the stereotyped alignment of central retinal projections relies on an initial spatially organized distribution of molecules in both the retina and its central target nuclei. We used an immunological approach to look for molecules that are so organized and produced a monoclonal antibody (JONES) which shows a pronounced dorsal to ventral gradient of binding in the rat retina throughout the period when retinal ganglion cell axons are forming topographically organized projections within the central nervous system (CNS). Binding is present throughout the radial thickness of the retinal epithelium in regions where postmitotic neurones are generated but is not associated with any consistent histological characteristic of the tissue. The antibody was shown to bind on the cell surface of freshly dissociated retinal cells, and dorsal retinal quadrants were found in vitro to have nearly twice as much antigen as ventral retinal quadrants. Initial biochemical characterization of the target epitope reveals that it is a lipid present in chloroform/methanol extracts from perinatal retina and is sensitive to neuraminidase digestion.

Ex Output:
Animal

Ex Input:
Abstract: Slowly adapting pulmonary stretch receptors have been hypothesized to be the afferents mediating the vagally dependent, volume-related prolongation of expiratory time (TE) during expiratory loading. It has been further suggested that the vagal component of this prolongation of TE is due to the temporal summation of pulmonary stretch receptor (PSR) activity during expiratory loading. This hypothesis was tested in rabbits exposed to resistive and elastic single-breath expiratory loading while PSR's were simultaneously recorded. Both types of loads resulted in a decreased expired volume (VE) and increased expiratory duration (TE). The TE for resistive loads were significantly greater than for elastic loads for equivalent VE. Thus two different VE-TE relationships were found for resistive and elastic loads. When TE was plotted against the area under the expired volume trajectory, a single linear relationship was observed. PSR activity recorded during expiratory loading increased as VE decreased and TE increased. A single linear relationship resulted when the number of PSR spikes during the expiration was plotted against the associated TE for all types of loads. These findings demonstrate that the volume-related prolongation of TE with single-breath expiratory loads is associated with an increase in PSR discharge. These results support the hypothesis that the vagal component of load-dependent prolongation of TE is a function of both the temporal and spatial summation of PSR activity during the expiratory phase.

Ex Output:
Action Potentials