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1.
介绍一种操作简单、成本较低、便于医生确定靶肌肉的肌电引导治疗仪.该仪器经过临床初步试验,效果良好. 相似文献
2.
Dr Laszlo Gyermek MD Gloria Henderson CRNA 《Journal of clinical monitoring and computing》1992,8(2):131-135
Quantitative assessment of neuromuscular block produced by large doses of nondepolarizing neuromuscular blocking agents during cardiac surgery is not possible with conventional methods of monitoring. Various posttetanic responses can, however, be elicited, even when no twitch response is present. Posttetanic responses measured by electromyography were used in this study. Twenty-four male patients undergoing coronary bypass surgery were anesthetized with sufentanil plus diazepam. Neuromuscular block was provided either with pancuronium 0.1 mg/kg or with vecuronium 0.07 mg/kg initially and supplemented with small increments when indicated. Neuromuscular block was monitored from the hypothenar muscle. The ulnar nerve was stimulated by train-of-four, with supermposed periodic tetanic stimuli to evoke posttetanic responses, once every 7 to 15 minutes. The tetanically potentiated responses were detectable during 96% ± 3.6 (vecuronium) and during 97% ± 3.7 (pancuronium) of the entire intraoperative period, while the nonpotentiated electromyographic responses were present for less than 50% of the time. The sum (of the amplitudes) of 6 posttetanic responses is significantly (p<0.05) greater than the sum of 6 nonpotentiated responses and than the size of a single-peak posttetanic response when compared with the normal, nonpotentiated responses. Higher-frequency tetanic stimuli (100 or 200 Hz) produced greater posttetanic responses (p<0.05) than did the 50-Hz tetanic stimulus. There were only slight or no significant differences in the degree of posttetanic potentiation between pancuronium and vecuronium either before, during, or after cardiopulmonary bypass. With posttetanic responses, we could detect changes in the level of neuromuscular block that occur during cardiac surgery and that are related to cardiopulmonary bypass, cooling, rewarming, and large doses of corticosteroids and antibiotics. Furthermore, it was not necessary to extend the arm or to use an arm board (on which the hand is immobilized when using mechanical monitoring methods) during cardiac surgery. 相似文献
3.
Pincivero DM Coelho AJ Campy RM Salfetnikov Y Bright A 《European journal of applied physiology》2002,87(4-5):448-455
The purpose of this study was to examine the effect of voluntary contraction efforts on the median frequency (f
med) of the electromyogram (EMG) recorded from the quadriceps femoris muscle in healthy men and women. A group of 30 healthy
volunteers (15 men, 15 women) were assessed for EMG activity of the vastus medialis (VM), vastus lateralis (VL), and rectus
femoris (RF) muscles during isometric contractions with the knee at 60° flexion. Subjects performed a series of 5 s maximal
voluntary isometric contractions that anchored the perceptual range with a "10" on a 10-point scale. Sub-maximal isometric
contractions were then separately performed at the following perceived effort levels on the 10-point scale: 1, 2, 3, 4, 5,
6, 7, 8 and 9, in a random order. Subjects were instructed to maintain the contraction at each perceived level of effort for
5 s. The f
med of the three muscles was assessed using a power spectrum analysis performed over 11 consecutive, 512 ms, epochs overlapping
each other by half their length during the middle 3 s of each contraction. The f
med for each of the 11 epochs was then determined for each muscle, followed by calculation of the means and normalized coefficients
of variation [(standard deviation/mean)×100%] for each contraction. The results demonstrated that the mean f
med of VL was significantly greater than those of the other two muscles, and that f
med of RF was significantly greater than that of VM. The VL muscle demonstrated a significant increase in mean f
med across the contraction efforts, compared to the VM and RF muscles that displayed a significant decrease. The men displayed
significantly higher f
med values for the VM muscle than did the women, as well as showing a significantly greater increase across the contraction efforts
for the VL muscle. The variability of f
med was shown to be significantly higher for the VM muscle, compared to the VL and RF muscles. The findings of this study suggest
that the f
med statistic is most sensitive to contraction intensity efforts for the VL muscle, and that men display significantly higher
values for the VL and VM muscles, compared to women.
Electronic Publication 相似文献
4.
K. B. Shapovalova S. P. Poltavets M. I. Boiko 《Neuroscience and behavioral physiology》1985,15(3):254-264
A model of instrumental defensive reflexes associated with the maintenance of a specific posture was used in chronic experiments with four dogs to demonstrate the preferential inhibitory influence of preliminary low-frequency stimulation (2 impulses/sec) of the head of the caudate nucleus in the right and left hemispheres on the electromyographic and mechanographic components of the instrumental defensive reflex effecting the reflex motor program. Subjected to the greatest changes were the postural, components of the electromyogram, which permits the postulate as to the importance of the caudate head in the organization of posture. It was shown that the caudate head is bilaterally involved in the prerelease processes preceeding the instrumental response. At the same time, the difficulty of inhibiting the performance of the actual instrumental task- the avoidance of an electric current- was noted during stimulation of the caudate head in a system of instrumental defensive reflexes.Translated from Fiziologicheskii Zhurnal SSSR imeni I. M. Sechenova, Vol. 68, No. 11, pp. 1488–1499, November, 1982. 相似文献
5.
Tetsuo Takaishi Takashi Ono Yoshifumi Yasuda 《European journal of applied physiology》1992,65(4):335-339
Summary The surface electromyogram (EMG) from active muscle and oxygen uptake (
) were studied simultaneously to examine changes of motor unit (MU) activity during exercise tests with different ramp increments. Six male subjects performed four exhausting cycle exercises with different ramp slopes of 10, 20, 30 and 40 W · min–1 on different days. The EMG signals taken from the vastus lateralis muscle were stored on a digital data recorder and converted to obtain the integrated EMG (iEMG). The
was measured, with 20-s intervals, by the mixing chamber method. A non-linear increase in iEMG against work load was observed for each exercise in all subjects. The break point of the linear relationship of iEMG was determined by the crossing point of the two regression lines (iEMGbp). Significant differences were obtained in the exercise intensities corresponding to maximal oxygen uptake (
) and the iEMGbp between 10 and 30, and 10 and 40 W · min –1 ramp exercises (P < 0.05). However, no significant differences were obtained in
and
corresponding to the iEMGbp during the four ramp exercises. With respect to the relationship between
and exercise intensity during the ramp increments, the
-exercise intensity slope showed significant differences only for the upper half (i.e. above iEMGbp). These results demonstrated that the
and
at which a nonlinear increase in iEMG was observed were not varied by the change of ramp slopes but by the exercise intensity corresponding to
and the iEMGbp was varied by the change of ramp slopes. In addition, the significant differences in the
exercise intensity slopes for the upper half of the tests would suggest that the recruitment patterns of MU and/or muscle metabolic state might be considerably altered depending upon the ramp slope increments. 相似文献
6.
V. A. Lopatin M. L. Finkel' V. V. Barannikov O. V. Terekhov 《Bulletin of experimental biology and medicine》1978,85(1):112-114
To record the hysteresis loop and electromyogram of the diaphragm simultaneously it is recommended that a standard probe of the sort used to record the intraesophageal pressure, on which silver electrodes are mounted, be used. This method provides fuller information on the work of the respiratory muscles.Institute of Obstetrics and Gynecology, Academy of Medical Sciences of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR V. G. Baranov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 1, pp. 95–96, January, 1978. 相似文献
7.
H. W. Axelson 《Acta physiologica (Oxford, England)》2004,182(3):295-304
Aim: This study on healthy subjects explores history‐dependent changes in the resting tension of relaxed wrist muscles after moderate joint excursions and the motor control consequences of these changes during voluntary wrist joint position maintenance. Methods: Integrated surface electromyogram (IEMG) was recorded from wrist extensor/flexor muscles. Angular position and torque were recorded from the wrist joint. Changes in wrist flexor muscle resting tension were sensed by a force transducer pressed against the tendons. Results: Consecutive stepwise changes (7.5°) in wrist joint position (within the dorsiflexed range) were either imposed on relaxed subjects or actively performed while the subjects under visual guidance tried to mimic the passive movements. In relaxed subjects, passive joint torque resistance at a given steady dorsiflexed position either gradually declined or rose depending on the direction of the previous transition movements. In corresponding voluntary contraction experiments, the IEMG amplitude from position holding wrist extensors was found to vary in a similar way as the passive torque resistance. Further, there was a strong correlation between history‐dependent changes in extensor IEMG amplitude and stress alterations exhibited by the relaxed antagonist flexors. The above described, slowly subsiding post‐movement mechanical and motor adaptations were accelerated by brief forceful cocontractions of the forearm muscles. Conclusion: Moderate stepwise changes in joint position are sufficient to induce history‐dependent after‐effects in passive muscular resting tension, after‐effects which during voluntary position holding are effectively compensated for by the motor control system. 相似文献
8.
9.
实验以膈肌肌电图(EMGdi)及膈肌诱发电位为指标,观察辅助酶Q10对兔膈肌作用,发现:(1)复制膈肌疲劳(DIF)后静脉注射CoQ10mg/kg,对DIF有治疗作用,(2)提前1静脉注射CoQ1010mg/kg预处理,对电致作膈肌有保护作用。 相似文献
10.
对136例周围神经损伤患者进行肌电图(EMG)与运动神经传导速度(MCV)分析。损伤神经支配的168块肌肉,EMG均为神经原性损害。166条受损神经MCV均有不同程度的减慢或缺失,其中周围神经完全断伤29.52%,严重损伤21.69%,中度损伤21.08%,轻度损伤27.71%。本文认为对周围神经损伤的定位和损伤程度的判断EMG和MCV是可靠和有效的方法。 相似文献