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Biomedical subjects

L M Hughes

Publications and source records attributed to L M Hughes.

5 recordsLinked to original sources

Chronic diazepam administration and appetitive discrimination learning: acquisition versus steady-state performance in pigeons.

Chronic injections of 2 mg/kg diazepam disrupted both steady-state performance and new discrimination learning in pigeons. However, the time course of disruption differed for each of the two tasks, i.e., steady-state performance was briefly disrupted early, whereas acquisition showed a more persistent delayed disruption. The difference was interpreted as resulting from a dual effect of diazepam on behavior. The early performance disruption was thought to reflect a general nonspecific sedative action of the drug, while the delayed disruption of learning was interpreted as the result of diazepam's selective interference with acquisition processes. Some support for rapid adjustment to the sedative effects of diazepam was found, but there was no evidence for the development of physiological tolerance to diazepam-induced acquisition deficits.

Animals↗

Clinical syndromes of mastalgia.

232 patients attending a breast clinic with breast pain as the primary presenting symptom were studied prospectively to define clinical syndromes and to attempt to elucidate aetiological factors. Those women in whom mastalgia was a minor aspect of their complaint, or who were primarily seeking reassurance that they did not have cancer, were excluded. Most mastalgia patients could be placed into well-defined subgroups on the basis of clinical, radiological, and pathological features. After excluding causes of pain arising outside the breast, six specific groups with widely differing aetiological bases were defined, leaving only 7% unclassified lithout known aetiology. The six defined groups were cyclical pronounced mastalgia, (believed to be hormonally based), duct ectasia. Tietze syndrome, trauma, sclerosing adenosis, and cancer. Psychological factors were found to be less important than has been previously suggested. Classification of patients with mastalgia into homogeneous subgroups is a prerequisite of any therapeutic study.

Adolescent↗