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1.
Nerve growth factor (NGF) and NGF receptors were measured in cortex and hippocampus of rats treated with drugs affecting cholinergic neurotransmission. High (Kd= 0.045nM) and low (Kd= 21nM) affinity125I-NGF binding sites were present in both cortical and hippocampal membranes with hippocampus containing higher numbers of both sites than cortex. Chronic treatment of rats with the muscarinic receptor antagonist scopolamine (5 mg/kg, twice daily) decreased the density of high- and low-affinity sites by 50–90% in cortical and hippocampal membranes. These changes were seen after 7 days, but not 3 days, of scopolamine treatment. Chronic infusion of physostigmine (1 mg/kg/day) using minipumps increased the number of high- and low-affinity sites in cortex 3- and 6-fold, respectively. The changes in receptor-binding parameters induced by physostigmine were transient as they were evident after 3 days of treatment, but returned to control levels after 7 days. NGF content in cortex and hippocampus was reduced by about 50% following 7, but not 3, days of chronic physostigmine infusion. In contrast, scopolamine treatment failed to change NGF levels in the cholinergic neuronal target regions but it decreased NGF content in the septal area. The content of NGF mRNA in the cortex measured by Northern blot analysis failed to change following either scopolamine or physostigmine treatment. The results suggest that levels of NGF and NGF receptors in the target regions of cholinergic neurons are regulated by the extent of cholinergic neurotransmitter activity. 相似文献
2.
In the cat synapses between vesicle containing profiles were observed in ventral and dorsolateral pontine nuclei. The presynaptic elements consisted of two types of axon terminals: axon terminals characterized by a population of small (38-40 nm) round synaptic vesicles (SSV) and axon terminals containing pleomorphic synaptic vesicles (PSV). The postsynaptic pale elements (PP) had pleomorphic vesicles and some features attributed to dendrites. In the dorsolateral pontine nucleus most of PP profiles took part in serial synapses, usually as an intermediate component, they were rarely observed in triads. On the basis of their electron microscopical appearance and synaptic relations they might be considered to represent a dendritic part of putative interneurons. 相似文献
3.
Diagnostic validity of the criteria of myocardial ischemia in coronary patients exposed to the treadmill test is assessed. The risk of a false diagnosis of coronary insufficiency on the basis of the pain syndrome was 5 times as high as that of diagnosis based on ischemic electrocardiographic ST depression. In subjective assessment of walking tolerance, patients with severe angina were particularly prone to mistakes. Limitations of angina classifications by severity, based on subjective sensations of coronary patients, are considered. 相似文献
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Based on the experience with treatment of 26 patients the authors recommend to use mainly conservative treatment with the intrapleural administration of fibrinolytic drugs. The method was used in 20 patients. All of them recovered. 相似文献
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The authors describe results of using endoscopic papillosphincterotomy in 100 patients with acute pancreatitis. Methods of endoscopic papillosphincterotomy and endoscopic papillosphincterowirsungotomy are presented. The effectiveness of the treatment was 96%. Operative procedures on emergency made up 1%, lethality-1%, complications-3% of the cases. 相似文献
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S V Ivanov V E Kudriashev Iu V Beletski? G E Zolichev 《Vestnik khirurgii imeni I. I. Grekova》1990,144(2):47-51
A method of diagnostics and assessment of the severity of arterial insufficiency of lower extremities was developed on the basis of multistep treadmill-test and measuring time of reestablishment of continuous bloodflow in the popliteal artery by the method of ultrasonic doppler flowmetry. An examination of 40 patients with angiographically detected alterations of the vessels and 18 healthy persons was performed. It was found that the diagnostic and assessment criterion of arterial insufficiency in treadmill-test with high parameters of sensitivity and specificity is longer duration of the period of reestablishment of continuous bloodflow over 180 sec. The arterial insufficiency severity is estimated by the value of exercise by the moment of the appearance of the criterion. 相似文献
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