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1.
The action of continuous low-frequency vibration on rats for 1 month caused no changes in the total adenine nucleotides of the brain but led to a marked decrease in the ATP content and total adenine nucleotides in the limb muscles. After exposure to vibration for 3 months considerable exhaustion of the total adenine nucleotides of both muscles and brain was found. In the case of interrupted exposure to vibration the state of the adenine-nucleotide system depended on the duration of the pauses between periods of continuous exposure to vibration. During vibration with the shortest pauses (4 min) between successive periods of 30 min of vibration no changes were observed in the energy metabolism of the muscles and brain. Vibration with pauses of 8 and 15 min was found to be unfavorable for the adenine nucleotides of the muscles and vibration with a pause of 8 min for the brain.Kiev Institute of Work Hygiene and Occupational Diseases, (Presented by Academician of the Academy of Medical Sciences of the USSR L. I. Medved'.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 7, pp. 35–38, July, 1978.  相似文献   
2.
Photoplethysmography (PPG) records the cardiac-induced changes in tissue blood volume by light-transmission measurements. The baseline and amplitude of the PPG signal show very low-frequency (VLF) spontaneous fluctuations, which are mediated by the sympathetic nervous system, and high correlation between right and left extremities of healthy subjects. As sympathetic neuropathy is one of the diabetic complications, the right-left correlation of the PPG fluctuations was examined in diabetic patients. The PPG signal was simultaneously measured in the two index fingers and the two second toes of 35 diabetic patients and 33 non-diabetic subjects. For each PPG pulse, the baseline and amplitude were determined, and the right-left correlation coefficients of the VLF fluctuations in the baseline and amplitude were derived. The VLF fluctuations in the baseline showed high right-left correlation, both for fingers (0.93±0.05) and toes (0.93±0.06), for the non-diabetic subjects, and significantly lower correlation (0.78±0.22 and 0.84±0.17, respectively) for the diabetic patients. Similar results were obtained for the amplitude VLF fluctuations. The right-left correlation coefficients for diabetic patients decreased with the disease duration for the toe baseline and toe amplitude fluctuations and correlated with heart rate response to deep breathing for the finger baseline and toe amplitude fluctuations. The right-left correlation coefficients of the PPG fluctuations provide a simple and convenient means for assessing the adequacy of the sympathetic nervous system function.  相似文献   
3.
低频超声增透效应   总被引:4,自引:0,他引:4  
50年前人们就发现了超声的增透效应,经过40年的研究对比发现低频超声(20kHz〈f〈100kHz)更有利于促进分子的透皮传输。低频超声之所以具有较高的增透效应是因为该频段有利于空化作用的发生。发生在皮肤表面附近的惯性空化作用在低频超声增透效应中发挥主要作用。影响低频超声增透效应的既有超声因素又有非超声因素。关于超声因素的研究已比较成熟,但有关非超声因素的研究报道还很少。人们已将低频超声增透效应用于药物透皮注入.并在积极进行将低频超声增透效应用于微创透皮检测的研究。此项研究充满机遇和挑战。  相似文献   
4.
目的探讨耳后注射曲安奈德配合金纳多银杏叶提取物片治疗单侧急性低频下降型感音神经性聋(ALHL)临床疗效。方法选取2014-05—2016-09开封市祥符区中医院收治的78例单侧ALHL患者,通过随机数字表法分为研究组与对照组各39例。对照组采用舒血宁注射液+地塞米松注射液治疗,研究组采用曲安奈德+金纳多银杏叶提取物片治疗,2组均持续治疗10d。疗程结束后对比2组临床疗效、不良反应发生率,分析治疗前后血清免疫功能指标(IgM、IgG、CD3~+、CD4~+)水平变化。结果研究组总有效率为94.87%(37/39),高于对照组的74.36%(29/39),差异有统计学意义(P0.05);治疗前2组IgM、IgG、CD3~+、CD4~+水平比较差异无统计学意义(P0.05),治疗后研究组IgM、IgG、CD3~+、CD4~+水平高于对照组,差异有统计学意义(P0.05);研究组不良反应发生率7.69%(3/39),与对照组10.26%(4/39)比较,差异无统计学意义(P0.05)。结论耳后注射曲安奈德配合金纳多银杏叶提取物片治疗单侧ALHL效果显著,可有效提高患者听力水平,且对改善其免疫功能具有重要作用,安全性较高,值得推广。  相似文献   
5.
6.
目的:观察低频电刺激对急性脑梗死后睡眠障碍的临床效果。方法:以2018年8月~2019年7月作为研究时段,选择此期间本院接收的急性脑梗死后睡眠障碍患者,共80例,将其随机编号,利用数表法分对照组、观察组,各40例。对照组给予常规治疗,观察组在前者基础上进行低频电刺激治疗,比较两组患者的临床效果和睡眠质量。结果:观察组患者的临床总有效率为95.00%,高于对照组的77.50%,差异有统计学意义(P<0.05);两组患者治疗前睡眠质量评分组间比较,差异无统计学意义(P>0.05),治疗后两组评分均较治疗前降低,组间进行比较观察组更低,差异有统计学意义(P<0.05)。结论:在急性脑梗死后睡眠障碍患者治疗中,低频电刺激治疗能够改善患者睡眠情况,提高其睡眠质量,值得借鉴。  相似文献   
7.

Background

Major depressive disorder (MDD) is associated with altered neural activity in the default mode network (DMN). In the present study, we used a fractional amplitude of low-frequency fluctuations (fALFF) approach to directly investigate the features of spontaneous brain activity of the DMN in patients with the first-episode, drug-naive MDD at rest.

Methods

Twenty-four first-episode, drug-naive patients with MDD and 24 age-, gender-, and education-matched healthy subjects participated in the study. The fALFF and independent component analysis (ICA) approaches were utilized to analyze the data.

Results

Patients with MDD exhibited a dissociation pattern of resting-state fALFF in the DMN, with increased fALFF in the left dorsal medial prefrontal cortex (MPFC) and decreased fALFF in the left parahippocampal gyrus (PHG). The increased fALFF values of the left dorsal MPFC were positively correlated to the Hamilton Rating Scale for Depression (HRSD) scores.

Conclusions

Our results first suggested that there was a dissociation pattern of resting-state fALFF in the DMN in patient with MDD, which highlighted the importance of the DMN in the pathogenesis of MDD.  相似文献   
8.

Objective

We hypothesize that the amplitude of low-frequency fluctuations (ALFF) is involved in the altered regional baseline brain function in social anxiety disorder (SAD). The aim of the study was to analyze the altered baseline brain activity in drug-naive adult patients with SAD.

Methods

We investigated spontaneous and baseline brain activities by obtaining the resting-state functional magnetic resonance imaging data of 20 drug-naïve adult SAD patients and 19 healthy controls. Voxels were used to analyze the ALFF values using one- and two-sample t-tests. A post-hoc correlation of clinical symptoms was also performed.

Results

Our findings show decreased ALFF in the bilateral insula, left medial superior frontal gyrus, left precuneus, left middle temporal gyrus, right middle temporal pole, and left fusiform gyrus of the SAD group. The SAD patients exhibited significantly increased ALFF in the right inferior temporal gyrus, right middle temporal gyrus, bilateral middle occipital gyrus, orbital superior frontal gyrus, right fusiform gyrus, right medial superior frontal gyrus, and left parahippocampal gyrus. Moreover, the Liebowitz Social Anxiety Scale results for the SAD patients were positively correlated with the mean Z values of the right middle occipital and right inferior occipital but showed a negative correlation with the mean Z values of the right superior temporal gyrus and right medial superior frontal gyrus.

Conclusion

These results of the altered regional baseline brain function in SAD suggest that the regions with abnormal spontaneous activities are involved in the underlying pathophysiology of SAD patients.  相似文献   
9.

Background

We report the utility of combining lung sound analysis and fractional exhaled nitric oxide (FeNO) for phenotype classification of airway inflammation in patients with bronchial asthma.We investigated the usefulness of the combination of the expiration-to-inspiration sound power ratio in the mid-frequency range (E/I MF) of 200–400 Hz and FeNO for comprehensively classifying disease type and evaluating asthma treatment.

Methods

A total of 233 patients with bronchial asthma were included. The cutoff values of FeNO and E/I MF were set to 38 ppb and 0.36, respectively, according to a previous study. The patients were divided into 4 subgroups based on the FeNO and E/I MF cutoff values. Respiratory function, the percentages of sputum eosinophils and neutrophils, and patient background characteristics were compared among groups.

Results

Respiratory function was well controlled in the FeNO low/E/I MF low group (good control). Sputum neutrophil was higher and FEV1,%pred was lower in the FeNO low/E/I MF high group (poor control). History of childhood asthma and atopic asthma were associated with the FeNO high/E/I MF low group (insufficient control). The FeNO high/E/I MF high group corresponded to a longer disease duration, increased blood or sputum eosinophils, and lower FEV1/FVC (poor control).

Conclusions

The combination of FeNO and E/I MF assessed by lung sound analysis allows the condition of airway narrowing and the degree of airway inflammation to be assessed in patients with asthma and is useful for evaluating bronchial asthma treatments.  相似文献   
10.
Chronic exposure to Industrial Noise (IN), rich in Low Frequency Noise (LFN), causes systemic fibrotic transformation and sustained stress. Dental wear, significantly increased with exposure to LFN, affects the teeth particularly through the circumpulpar dentin. Our goal is to understand the consequences of IN exposure on the circumpulpar dentin of Wistar rats. 10 Wistar rats were exposed to IN for 4 months, according to an occupationally simulated time schedule and 10 animals were used as age-matched controls. The first and the second upper and lower molars of each animal were processed for observation by Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive Spectroscopy (EDS) analysis was performed. In exposed animals FESEM showed a 2.0 to 6.0 μm-dense mineral band between dentin and the pulp with no regular continuity with the tubules. This structure had a few tubules where the odontoblasts processes could be observed embedded within the band and collagen fibers were trapped inside. EDS analysis revealed that it was hydroxyapatite similar to dentin, with a higher carbon content. FESEM results show that the band may be tertiary reparative dentin formed by odontoblast-like cells, but the increased amount of carbon (EDS) could mean that it is sclerotic dentin. IN should be acknowledge as a strong stimulus, able to cause an injury to odontoblasts and to the formation of reparative tertiary dentin, in a process that may accelerate the aging of the teeth, either by direct impact of acoustic pressure pulsations or by increased stress and dental wear.  相似文献   
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