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971.
J R Glowa J D Bacher M Herkenham P W Gold 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(3):379-391
1. Rhesus monkeys were equipped with a novel intracerebroventricular (i.c.v.) cannula system and trained to respond under operant schedules of food presentation or termination of stimuli associated with the delivery of shock (escape). 2. CRH decreased food-maintained behavior in a dose-related manner over the range of (0.3-10 micrograms/kg) but did not affect escape responding, demonstrating a selective effect on food-maintained responding. 3. This selective effect was related to the tendency for responding to stop after delivery of a food pellet when higher doses of CRH were given, consistent with the notion that a conditioned aversion to food was established in the presence of CRH. 4. This may suggest that in hyperaroused clinical states such as depression and anorexia nervosa, focus is shifted away from appetitive tasks as a result of increased levels of CRH. 相似文献
972.
S. T. F. M. Frequin F. J. M. Gabreë ls A. A. W. M. Gabreë ls-Festen E. M. G. Joosten 《Clinical neurology and neurosurgery》1991,93(4):323-326
A girl of 14 year is presented with a distal spinal muscular atrophy (SMA) with autosomal recessive inheritance. The technical findings are in agreement with the diagnosis. Light microscopical examination of sural nerve biopsy, including teased fiber studies and morphometry, showed no abnormalities. Electron microscopical investigation however demonstrated axonal pathology. The question arises if distal SMA is a distal axonopathy mainly of motor nerves, but to some extent also of sensory nerves. 相似文献
973.
Summary The prevalence of smoking, hypertension and diabetes mellitus was assessed in 221 patients suffering from internal carotid stenosis and compared with the prevalences in two sex- and age-matched control groups composed of subjects having normal Doppler findings and from non-neurological outpatients. Of the subjects with carotid stenosis 27.6% were hypertensive smokers in comparison with 9.5% and 17.2% in the two control groups. The difference of the stenosis cohort from the two control groups was significant (P<0.01 and P=0.016 respectively). There was no statistically significant differences between the occurrence of diabetes and hypertension in non-smokers and patients who smoked. In 394 investigated patients suffering from carotid stenosis or occlusion an obstruction index, based on the Doppler shift frequency, was calculated. This index was lowest in the normotentive non-smokers. It was only insignificantly higher in the hypertensive non-smokers but significantly so in the normotensive smokers. The index was highest in the hypertensive non-smokers. It was concluded that cigarette smoking, especially if associated with hypertension, is a determinant risk factor for carotid stenosis and occlusion. 相似文献
974.
Olgierd Pucilowski W. Danysz D.H. Overstreet A.H. Rezvani B. Eichelman D.S. Janowsky 《Brain research bulletin》1991,26(4):621-625
The Flinders Sensitive Line (FSL) of rats has been selectively bred to have increased sensitivity to cholinergic agonists. However, these rats exhibit altered responsiveness to a number of noncholinergic agents, such as apomorphine, buspirone and ethanol. This study compared the FSL and control Flinders Resistant Line (FRL) rats in terms of their hyperthermic response to the phencyclidine (PCP) receptor agonist, MK-801 (0.2 mg/kg SC) and their MK-801 binding characteristics. We have found that FSL rats react with a delayed hyperthermia, having a significantly lower hyperthermia for the first 120 min of observation. Thereafter the response does not differ in FSL and FRL rats. Both groups had similar affinities and numbers of [3H]MK-801 binding sites in the hippocampus/cerebral cortex. Pretreatment with scopolamine (1 mg/kg SC) failed to affect MK-801-induced hyperthermia in either line of rats. These findings suggest that selective breeding of FSL rats attenuated the secondary mechanisms involved in the PCP receptor-mediated hyperthermic response. However, by itself cholinergic supersensitivity does not appear to be a major factor in the blunted responsiveness of FSL rats to MK-801. 相似文献
975.
976.
32nd Annual Meeting of the Scandinavian Society for Psychopharmacology Copenhagen, Denmark April 10–12, 1991 Abstracts 相似文献
977.
Synaptic contacts between growth hormone-releasing hormone (GHRH)- and somatostatin-containing neurons were demonstrated in the rat hypothalamus by a double-staining immunocytochemical method at the electron microscopic level. Somatostatin-immunoreactive nerve terminals synapse on GHRH-positive dendrites and cell bodies in the arcuate nucleus. A fine network of GHRH-immunopositive nerve terminals was observed at the light microscopic level in the rostral part of the periventricular nucleus and in the dorsal part of the arcuate nucleus around somatostatin-containing neuronal elements. With the electron microscope synaptic contact between GHRH-containing nerve terminals and somatostatin-containing dendrites are demonstrated. The reciprocal innervation between GHRH- and somatostatin-containing neurons that project to the median eminence and regulate growth hormone secretion must allow them to coordinate their activities. 相似文献
978.
M T Hegel G G Abel M Etscheidt S Cohen-Cole C I Wilmer 《Journal of behavior therapy and experimental psychiatry》1989,20(1):31-39
The hyperventilation syndrome is present in as many as 50% of patients with non-cardiac chest pain. This study evaluated a behavioral treatment of this disorder in three adult females. They had long histories of chest pain and were documented to be free of coronary artery disease. Each subject met the DSM-III-R diagnostic criteria for an anxiety disorder. Following treatment, all subjects showed a marked decrease in the frequency and intensity of chest pain episodes and in the frequency of shortness of breath episodes. Two subjects maintained their progress at one-year follow-up. The results lend support to the efficacy of controlled breathing and relaxation training for the treatment of hyperventilation-related chest pain and to the inclusion of a hyperventilation provocation test in the diagnosis of the syndrome as well as its role in changing cognitions regarding cardiac status. Also discussed is the rationale for treating hyperventilation related chest pain in a medical care setting. 相似文献
979.
Sixty chronic alcoholic patients, aged 35.6 +/- 0.7 years and an average alcoholic history of 9.3 +/- 0.5 years were examined. Atrial fibrillation was detected at 24 h ECG monitoring in 2 (3.45%) patients, and paroxysms of atrial fibrillation or flutter were detected by intracardiac electrophysiologic investigation in 6 (22.2%). Fourteen (44.8%) patients with alcoholic heart damage demonstrated atrial vulnerability, indicative of a predisposition to atrial fibrillation even at earlier stages of alcoholic heart damage. 相似文献
980.