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81.
F. Fotiou K. N. Fountoulakis A. Goulas L. Alexopoulos A. Palikaras 《Clinical physiology and functional imaging》2000,20(5):336-347
The aim of the current study was the introduction and standardization of two experimental conditions for dynamic pupillometry. Pupillometry is a method that can provide valuable data concerning the functioning of the autonomous nervous system. The system for recording the pupil reaction was developed in the Laboratory of Clinical Neurophysiology of the 1st Department of Neurology of Aristotle University of Thessaloniki, in co‐operation with the Laboratory of Fluid Mechanics of the Aristotle University of Thessaloniki. This system is fully automated. It includes an infra‐red video camera, which has the capacity to record in complete darkness, and an SLE (clinical photic stimulator) lamp. A software application automatically performed all the procedures. During the first experiment, one flash was administered. During the second experiment, a series of 25 flashes (1 Hz frequency) was administered. Fifty physically and mentally healthy subjects aged 23–48 years took part in the study. Means, standard deviations and ranges for all variables characterizing normal subjects during both experimental conditions are reported. Test/re‐test results and comparisons of the two eyes are also reported. The combined use of these two experimental conditions in dynamic pupillometry may be a very useful tool in medical research. There are already reports on the usefulness of pupillometry in the research of various diseases, including depression and Alzheimer’s disease. It is expected that it will also be a valuable research tool in the study of diabetes, alcoholism, myasthenia gravis, cancer, multiple sclerosis, etc. 相似文献
82.
Epidural infiltration by leukemic cells in Acute Non Lymphoblastic Leukemia (ANLL), and extradural granulocytic sarcomas as a cause of spinal cord compression are extremely rare phenomena. Very few cases have been recorded in the literature. In this brief case report we describe a young patient with acute myeloblastic leukemia (M4, FAB) who presented with sudden spinal cord compression during relapse after bone marrow transplantation. The literature on this subject is also reviewed. 相似文献
83.
Yang-Chyuan Chang Ching-Ying Yeh Jung-Der Wang 《American journal of industrial medicine》1995,27(2):271-279
Pattern visual, brainstem auditory, and somatosensory evoked potential (EP) studies were performed on 26 chloralkali workers. The intensity of mercury vapor exposure in these workers was estimated from the individual working history. Mercury levels in blood, urine, and hair were determined with atomic absorption spectrometry. The EP findings were compared with those from individually matched normal subjects. In brainstem auditory and somatosensory EP studies, prolonged neural conduction times in the central nervous system (CNS) were found in workers exposed to mercury vapor. In the pattern visual EP study, mercury workers had higher interpeak amplitudes. Findings of this study suggested that chronic exposure to mercury vapor would affect the CNS functions. A multimodality EP study is a useful adjunct in evaluation of chronic mercury neurotoxicity, especially in an epidemiological study. 相似文献
84.
Chinori Kurata MD PhD Sakae Shouda MD Tadashi Mikami MD Yasushi Wakabayashi MD Tomoyasu Nakano MD Tsuyoshi Sugiyama MD Kei Tawarahara MD PhD Kazuyuki Sakata MD PhD 《Journal of nuclear cardiology》1997,4(6):515
Background. [123I]Metaiodobenzylguanidine (MIBG) imaging has been used to assess cardiac sympathetic nerve abnormalities. We evaluated the clinical significance of myocardial MIBG imaging as a measure of cardiac sympathetic nervous system function by comparing it to heart rate variability and plasma norepinephrine level.Methods and Results. In 211 subjects, we analyzed heart rate variability with 24-hour electrocardiography, performed scintigraphy with MIBG, and measured plasma norepinephrine levels. Time and frequency domain measures of heart rate variability were calculated with the Marquette heart rate variability program (Marquette Electronics, Milwaukee, Wis.). Early and late myocardial MIBG uptakes were measured at 15 and 150 minutes after injection, respectively. MIBG clearance rate from the heart and heart-to-lung and heart-to-mediastinum ratios of MIBG activities were calculated. On the whole, heart rate variability, including low-frequency power, correlated positively, but modestly so, with late MIBG uptake and negatively with MIBG clearance rate. The plasma norepinephrine level correlated negatively with late MIBG uptake and with heart rate variability, including low-frequency power, and positively with MIBG clearance rate. Similar correlations were also observed in patient subgroups with coronary artery disease, diabetes mellitus, and renal failure, but these correlations were weak (R2 < 0.5).Conclusions. Increased cardiac sympathetic nervous system activity may be associated with increased myocardial MIBG clearance and decreased heart rate variability, including low-frequency power. Because these associations were not strong, however, the combination of heart rate variability with MIBG may allow an interactive assessment of the cardiac autonomic nervous system. 相似文献
85.
Thoracic epidural analgesia in aortocoronary bypass surgery II: effects on the endocrine metabolic response 总被引:3,自引:0,他引:3
R. STENSETH L. BJELLA E. M. BERG O. CHRISTENSEN O. W. LEVANG S. E. GISVOLD 《Acta anaesthesiologica Scandinavica》1994,38(8):834-839
Thoracic epidural analgesia (TEA) may offer haemodynamic benefits for patients with coronary heart disease going through major surgery. This may – in part – be secondary to an effect on the endocrine and metabolic response to surgery. We therefore investigated the effect of TEA on the endocrine metabolic response to aortocoronary bypass surgery (ACBS).
Thirty male patients (age < 65 years, ejection fraction > 0.5) were randomized into 3 groups; the HF group receiving a high dose fentanyl (55 μg–kg-1 ) anaesthesia, the HF + TEA group with the same fentanyl dose + TEA with 10 ml bupivacain 5 mg ml-1 , followed by 4 ml every hour, and the LF + TEA group receiving fentanyl 15 μg kg-1 + TEA. Adrenalin, noradrenalin, systemic vascular resistance (SVR), glucose, Cortisol, lactate and free fatty acids were followed during the operation and for 20 h postoperatively.
A significant increase in adrenalin, noradrenalin and SVR was found in the HF group whereas this increase was blocked in both epidural groups. An increase in glucose and Cortisol was noticed in all groups, but the increase was delayed in the epidural groups.
Our results suggest that a more effective blockade of the stress response during ACBS is obtained when TEA is added to general anaesthesia than with high dose fentanyl anaesthesia alone. 相似文献
Thirty male patients (age < 65 years, ejection fraction > 0.5) were randomized into 3 groups; the HF group receiving a high dose fentanyl (55 μg–kg
A significant increase in adrenalin, noradrenalin and SVR was found in the HF group whereas this increase was blocked in both epidural groups. An increase in glucose and Cortisol was noticed in all groups, but the increase was delayed in the epidural groups.
Our results suggest that a more effective blockade of the stress response during ACBS is obtained when TEA is added to general anaesthesia than with high dose fentanyl anaesthesia alone. 相似文献
86.
Autonomic dysfunction in chronic liver disease 总被引:1,自引:0,他引:1
Chronic liver disease is accompanied by a number of circulatory changes including impairment of cardiovascular autonomic reflexes. This occurs irrespective of the aetiology of liver disease, increases in prevalence and severity with worsening hepatic function, and is related at least in part to an autonomic neuropathy. Parasympathetic abnormalities predominate and, although largely subclinical, they may play a role in the altered fluid homeostasis and neurohumoral disturbances associated with cirrhosis. On prospective follow up, the presence of autonomic impairment was associated with a five-fold increased mortality, largely from sepsis and variceal haemorrhage. Defective responses to such stressful events as a result of an afferent defect could possibly explain these findings. Further studies are required to evaluate the natural history of this complication, and determine if it is reversible with improvement in hepatic function or after liver transplantation.Professor Triger passed away on 13 March 1993. His obituary appears on page 283. 相似文献
87.
研究背景 轮状病毒性胃肠炎是婴幼儿期最常见腹泻疾病之一。国内外对轮状病毒中枢神经及肺部感染告道甚少。 研究方法 用电镜、免疫电镜、酶联免疫吸附与阻断试验确诊轮状病毒中枢神经及肺部感染。 研究结果 200例轮状病毒性胃肠炎患儿中,并发轮状病毒性脑膜炎一例,轮状病毒性肺炎2例,其中1例同时合并胸膜炎、胸腔积液。 结论 轮状病毒中枢神经及肺部感染预后良好。 相似文献
88.
For the purpose of obtaining information on the maturation process of the autonomic nervous system in pre- and full-term infants, polygraphs were recorded during sleep from a total of 52 appropriate-for-dates infants at a conceptional age of 28–41 weeks. The 104 RR interval time series was calculated by auto-regressive (AR) and component analysis. Histograms of damping frequencies obtained were divided into two frequency bands: low frequency fluctuations (LF) of less the 0.1 cycle/beat (c/b) and high frequency fluctuations (HF) of more than 0.15 c/b. Total power and LF power decreased with increases in the conceptional age or postnatal age at a significance level of 0.01, respectively. In addition, the HF amount of bio-informing activity increased (P< 0.001) and the damping time of HF also increased (P <0.01). From these results, it was speculated that the activity of the sympathetic system decreases with increases in conceptional or postnatal age. It was also speculated that increased regularity and oscillatory duration in HF might be caused by the development of the reciprocal response of respiration to heart rate variation. 相似文献
89.
We present an atypical case of peripheral nervous system (PNS) involvement in Sjogren's syndrome in a 63 year-old woman. Symptoms of an entrapment neuropathy were the first manifestation of the systemic disease and they were subsequently coupled to those of a mononeuritis multiplex. Clinical and laboratory signs for the diagnosis of Sjogren's syndrome became subsequently overt. The mononeuritis multiplex remained clinically limited to the upper limbs and characterized by unusually severe motor symptoms which progressed up to the development of a final complete deplegia. By contrast, sensory symptoms at the upper limbs remained mild over the entire course of the disease and the lower limbs revealed a subclinical sensory-motor damage only during the late stage. 相似文献
90.
Summary In an autopsied case of a 37-year-old man with acquired immune deficiency syndrome (AIDS), multinucleated giant cell encephalopathy was noted in close proximity to multiple nodules of primary lymphoma of the brain. Some multinucleated giant cells and macrophages contained HTLV-III-like viral particles. Nuclear bridges, thin strands connecting individual nuclei with one another, were observed with both light and electron microscopes within some of the multinucleated giant cells. There were also thin tapering nuclear processes, which were probably part of nuclear bridges. The possibility that the nuclear bridges and processes represent amitotic nuclear division is discussed. 相似文献