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991.
J B Jensen J J Pease R ten Bensel B D Garfinkel 《Journal of the American Academy of Child and Adolescent Psychiatry》1991,30(5):784-790
The ratio of growth hormone response to clonidine and L-dopa challenge was compared in 74 boys: 15 with purported physical abuse, 7 with purported sexual abuse, 13 normal controls, and 39 psychiatric controls. Sexually abused boys demonstrate a statistically significant elevated ratio of growth hormone response to clonidine versus response to L-dopa. Physically abused boys demonstrate lower clonidine/L-dopa growth hormone response ratios compared with controls. These effects widen with increasing physical development. 相似文献
992.
When blood flow through the internal and external carotid arteries is completely interrupted by ipsilateral common carotid artery occlusion, the arterial orbital circulation may be more compromised than the brain supply. We studied a pure and extreme example of this situation in a patient who presented with acute orbital infarction, but no cerebral ischemia on clinical, CT and single-photon emission computerized tomography (SPECT) grounds. Ipsilateral blindness corresponded to retinal, choroidal and optic nerve infarction. The pattern of ophthalmoplegia, with relative sparing of adduction, was more compatible with a muscle than a nerve dysfunction, but a reactive dilated pupil, corneal anesthesia, and orbital pain suggested that the intraorbital branches of the ocular motor nerves and ophthalmic division of the trigeminal nerve were not spared. In addition, signs of widespread ocular ischemia were present. Sequential examinations documented the evolution pattern over 1 year. The absence of an orbital collateral supply from the contralateral external carotid and muscular cervical arteries systems, which contrasted with an adequate middle cerebral artery supply via the contralateral internal carotid artery, may explain this isolated and complete form of orbital ischemia due to common carotid artery occlusion. 相似文献
993.
The erythrocyte membrane transports (MT) of L-tyrosine and L-tryptophan, as well as their plasma levels, were measured in 143 depressed patients after a wash-out period of one week and before any antidepressant treatment, and then at regular intervals until they recovered. 49 normal subjects served as a control group. The perturbations of these biologic variables at baseline were different according to diagnostic groups (DSM III), compared to controls: significant decrease of the two MT in depressed bipolar disorders; significant decrease of MT in depressed bipolar disorders; significant decrease of MT tyrosine and significant increase of MT tryptophan in recurrent major depressions; no significant changes of MT in dysthymic disorders. The plasma levels of tyrosine and total tryptophan show a significant diminution in the 3 groups. The study of the evolution of these same variables after antidepressant treatment show a return to normal of the MT at recovery, as well as the plasma levels of tyrosine. The plasma levels of tryptophan stay low in depressed bipolar disorders and recurrent major depressions. 相似文献
994.
995.
Evidence that dopamine in the nucleus accumbens is involved in the ability of rats to switch to cue-directed behaviours. 总被引:2,自引:0,他引:2
R van den Bos G A Charria Ortiz A C Bergmans A R Cools 《Behavioural brain research》1991,42(1):107-114
Recently we have reported that injections of d-amphetamine into the nucleus accumbens enhanced the number of switches to cue-directed behaviours without an effect on the number of switches to non-cue-directed behaviours in a swimming test. In the present study we investigated to what extent this effect is mediated via the dopaminergic system in the nucleus accumbens. For that purpose drugs selective for D1- and D2-receptors were studied in this swimming test. It was found that the selective D2-agonist LY 171 555 (50 ng/0.5 microliters) enhanced the number of different cue-directed behaviours. The selective D2-antagonist raclopride (50 ng/0.5 microliters) decreased it. Furthermore an ineffective dose of raclopride attenuated the effect of LY 171 555. Both the selective D1-antagonist SCH 23390 (400 ng/0.5 microliters) and the selective D1-agonist SKF 38393 (50-400 ng/0.5 microliters) decreased the number of different cue-directed behaviours. The effect induced by SCH 23390 could not be blocked by SKF 38393. Similarly the effect induced by SKF could not be attenuated by SCH 23390. These data point to a role for dopamine D2-receptors in the ability to switch to cue-directed behaviours. The present findings do not yet allow the conclusion that D1-receptors are involved. 相似文献
996.
R R Love 《Preventive medicine》1991,20(1):64-78
Estrogenic hormones play critical roles in many aspects of women's health. Therefore, the impact of any hormonal manipulation must be carefully considered. While the evidence is good that chemoprevention, or more accurately chemosuppression, of breast cancer with tamoxifen is possible, further data are needed to support the case that hormone replacement with tamoxifen in healthy postmenopausal women would provide overall health benefits. Specifically, further data are needed regarding the biological effects of tamoxifen on risk factors for cardiovascular disease, on bone, on the liver, on the uterus, and on the coagulation system. Frequency, severity, and predictors for vasomotor, gynecologic, and depressant side effects also need to be well described. These data will allow rigorous cost-effectiveness analysis of hormone replacement therapies with tamoxifen and estrogen, as well as an analysis of the cost effectiveness of a clinical trial to prove definitively critical health benefits. 相似文献
997.
P Salem 《The Medical journal of Malaysia》1991,46(4):376-378
A thirty six week gestation male baby weighing three kilogram was born to a twenty five year old mother by spontaneous vaginal delivery. At four hours of life, the baby developed respiratory distress with cyanosis and was admitted to the neonatal intensive care unit. There was clinical and radiological evidence of bilateral pleural effusion. Thoracentesis revealed a transudate. Repeated thoracentesis was necessary to relieve the respiratory distress. Subsequently, multi resistant Klebsiella aerogenes was isolated from the blood. The baby expired due to gram negative sepsis. 相似文献
998.
V L Towle J C Witt S H Nader A T Reder R Foust J P Spire 《Electroencephalography and clinical neurophysiology》1991,80(5):339-346
Pattern visual evoked potentials were obtained from 46 patients with definite relapsing/remitting multiple sclerosis, using both a conventional 5-channel occipital array and a 3-D recording technique consisting of three bipolar derivations approximating the three dimensions of space. These three orthogonal wave forms were displayed as a 3-D Lissajous trajectory for each subject. Two of the 15 patients with completely normal conventional pattern VEPs had abnormalities of the orientation of the B-C curvilinear segment of the 3-D pattern VEPs. Delays in the first major occipital positive component (P100) were evident using both techniques; the correlation between P100 latency and the latency of the corresponding trajectory apex was r = 0.99 (P less than 0.01). Post-chiasmal MRI abnormalities were associated with 3-D VEP orientation abnormalities. Three-dimensional pattern VEPs are moderately more sensitive than conventional pattern VEPs at detecting dysfunction posterior to the optic chiasm in demyelinating disease and do not require the use of eccentric fixation to do so. 相似文献
999.
L P Dimnikova 《Neirofiziologiia》1991,23(5):574-579
Impulse activity of the anterior and posterior hypothalamus neurons was investigated in the unanaesthetised and anaesthetised (urethan and chloralose) rabbits. Anaesthesia is shown to induce a decrease of the mean firing rate, alteration of the impulse activity pattern and a decrease of the quantity of neurons, responding to the skin thermal stimulation. These changes are expressed most of all in the posterior hypothalamic neurons. 相似文献
1000.
P Tueting 《Psychiatric medicine》1991,9(2):333-347
This chapter will define investigational use for clinicians and outline FDA policies in this area in a simple and pragmatic way. Instances in which investigational use would require application to the FDA for an investigational New Drug Exemption (IND) and instances in which their use would require approval by an Institutional Review Board (IRB) will be described and examples given. 相似文献