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51.
Neuromuscular transmission as a function of motor unit size in patients with prior poliomyelitis. 总被引:2,自引:0,他引:2
We studied neuromuscular transmission in 16 patients with prior poliomyelitis by measuring single fiber electromyographic (SFEMG) jitter. This was compared with 3 indirect methods of assessing reinnervation: SFEMG fiber density, macro EMG, and the presence of fiber type grouping on muscle biopsy. In patients with acute poliomyelitis before the age of 10, there was a positive correlation between the extent of neuromuscular transmission impairment, demonstrated by increased SFEMG jitter, and the enlargement of the motor unit, as indicated by increased fiber density, increased macro EMG signals, and fiber type grouping on muscle biopsy. However, there was no correlation between any of these parameters and the presence or absence of new symptoms of weakness. These findings suggest that impaired neuromuscular transmission is most common in patients with prior poliomyelitis whose motor units have been maximally enlarged by axonal sprouting, but is independent of the presence or absence of new symptoms of weakness. 相似文献
52.
Stressors in ICU: patients’ evaluation 总被引:3,自引:0,他引:3
M. A. F. P. Novaes A. Aronovich M. B. Ferraz E. Knobel 《Intensive care medicine》1997,23(12):1282-1285
Objective: To study the physical and psychological stressors in the intensive care unit (ICU) and to correlate stressors with different
demographic variables. Design: Cross-sectional analytical survey. Setting: Intensive care unit of a private hospital. Patients and participants: 50 randomly selected ICU patients during the first week of their ICU stay. Measurements and results: The Intensive Care Unit Environmental Stressor Scale was administered to 50 patients. Pain and the impossibility of sleeping
due to noise and having tubes in the nose and mouth were considered the most important physical stressors. Loss of self control
and lack of understanding about the attitudes and procedures were the main psychological stressors. Conclusions: Interventions should be aimed at relieving the patient's pain and at controlling the level of noise to make sleep possible.
From the psychological standpoint, the independence of the patient should be encouraged, thus stimulating the recovery of
self-control. The team should also inform the patient about the procedures which will be carried out.
Received: 1 April 1997 Accepted: 24 September 1997 相似文献
53.
54.
Sik-Nin Wong Nelson N. S. Tsoi Chap-Yung Yeung 《Pediatric nephrology (Berlin, Germany)》1994,8(1):122-125
Intensive care services are expensive. The experience of developing a combined paediatric and neonatal intensive care unit (ICU) in a regional hospital is reported with reference to the provision of renal support for the critically ill patients. The combined unit is staffed by a team of paediatric intensivists, each of whom has special interest in a subspecialty, including cardiology, respiratory medicine, nephrology and neonatology. In the past 7 years, renal replacement therapy (peritoneal dialysis and haemofiltration) was provided to 40 patients, with comparable mortality and complication rates to other reports. This arrangement has been feasible and might be more efficient than running separate paediatric and neonatal ICUs or combining the paediatric ICU with the adult ICU. 相似文献
55.
The Effect of 50 Hz External Electrical Interference on Implanted Cardiac Pacemakers 总被引:2,自引:0,他引:2
GERALD C. KAYE GHAZWAN S. BUTROUS ALI ALLEN STUART J. MELDRUM JOHN G. MALE † A. JOHN CAMM 《Pacing and clinical electrophysiology : PACE》1988,11(7):999-1008
The effects of injected 50 Hz alternating current on the function of cardiac pacemakers has been observed in 18 patients with implanted unipolar VVI units. Current, in the range 0-600 microA was applied via electrodes attached to the patients' upper body and feet and fed from a specially designed current injection unit at the bedside. Most implanted pacemakers reverted to interference mode in the current range 29-250 microA. At current levels just below the reversion current all units developed irregular and inappropriate pacing. This current level was pacemaker dependent and varied in the range 27-246 microA. The total reversion current depended on the location of the injecting electrodes and on the patients' posture. The sensitivity of the units to injected interference was increased by deep inspiration. Temporary pacing catheters fitted to an additional ten patients were used to monitor the interference voltage which would be sensed by an implanted unit. This voltage was similarly dependent on patient posture and on deep respiration. Current injection has proved to be a safe, controllable and reproducible method of testing the sensitivity of implanted pacemakers to 50 Hz external interference. 相似文献
56.
为加速创建爱婴医院进程,昆明市妇幼保健院率先在全省开展了创建爱婴医院工作。他们大胆改革产科制度,实行母婴同室,建立健全了各项规章制度,实行母乳喂养系列化服务。 相似文献
57.
Unilateral lesion of the nigrostriatal pathway decreases the firing rate and alters the firing pattern of globus pallidus neurons in the rat 总被引:2,自引:0,他引:2
Activities of spontaneously firing neurons in the globus pallidus of intact rats and rats that survived unilateral lesions of the nigrostriatal pathway for 3 days, 1 week, or 6-11 weeks were compared. No significant differences in neuronal firing rate, firing pattern, and number of cells per pass were observed between chloral hydrate-anesthetized control and lesioned animals. However, in locally anesthetized animals, pallidal cells fired significantly faster than in chloral hydrate-anesthetized animals, and the lesion caused a decrease in the firing rates of pallidal cells 1 week and 6-9 weeks postlesion. In addition, significant differences in the firing pattern of pallidal cells, as determined by the ratio of the mean to median interspike intervals, were seen between locally anesthetized controls and animals surviving 3 days, 1 week, and 6-9 weeks postlesion. This altered firing pattern tended to return to normal with time. The number of cells per pass was not significantly altered by the lesion. Data from this study suggest that, in locally anesthetized animals, the removal of the tonic dopaminergic input to the basal ganglia causes pallidal cells to decrease their firing rates in a time-dependent fashion and causes reversable firing pattern changes. This suggests that tonically active dopamine neurons, probably acting through the striatopallidal pathway, regulate the firing rate and mechanisms controlling the temporal ordering of spontaneous discharges of globus pallidus neurons. 相似文献
58.
The apparent concentration-effect relationship is the ensemble of many effector units (such as individual cells or channels)
that do not always exhibit a uniform stimulus-effect relationship. This concept is substantiated by many observations of heterogeneity
in receptor-effector populations including hormone secreting cells, response to hormonal stimuli, activity pattern of second
messengers, stimulus-evoked synaptic currents, and single ion channels. The relationship between drug concentration and magnitude
of pharmacologic response is commonly described by the sigmoidalE
max model which was derived from the Hill equation. The sigmoidicity factor (N) in this model is assumed to be a pure mathematical parameter without physiological connotations. This work demonstrates
that the numerical value ofN (measured empirically) is the product of two factors: (i) the degree of heterogeneity of the effector subunits, i.e., the
elemental component that upon drug stimulus contributes its pharmacological effect independently and does not interact with
other subunits (it could range from a single receptor up to a whole tissue), and (ii) value ofN
*—the shape factor of the subunits' concentration-effect relationship. A special case of this approach occurs whenN
*>5, which is an on-off case. HereN is determined by the distribution (density equation) of the subunit values. In case of heterogeneity of the microparameters
of the effector subunits the apparentN will always have a lower value thanN
*. According to this theory it can be concluded that without knowledge of the distribution of the microparameters no mechanistic
interpretation can be deduced from the apparentN value. If in the futureN
* can be determined by theoretical or experimental methods, the distribution function relatingN
* toN can be calculated. The relevance of this theory is increased in view of the progress being made in advanced research techniques
which may enable us to determine the concentration-effect relationship at the level of the individual effector unit. 相似文献
59.
笔者结合单位的做法和体会,对医疗单位等在特殊药品使用管理中存在的问题,提出特殊药品的管理应法制化、职责化、程序化、档案化及提高业务素质、奖优罚劣的管理方法。 相似文献
60.
连续四年ICU病房院内感染病原菌的耐药性分析 总被引:4,自引:0,他引:4
目的 :了解我院重症监护病房 (ICU)院内感染病原菌的耐药性变化趋势。方法 :对我院 ICU2 0 0 0年 1月至 2 0 0 3年 12月院内感染的各类感染标本中分离的 74 1株病原菌加以整理分析 ,并按美国国家临床实验室标准委员会 (NCCL s)标准进行药敏试验 ,并对其耐药性进行分析。结果 :分离出的菌株以革兰阴性杆菌为主 ,其次是革兰阳性球菌、真菌 ,分别占 6 2 % ,2 9% ,9% ,感染部位以肺部最多 5 5 1株 (74 .4 % ) ,泌尿道感染 5 0株 (6 .7% ) ,引起败血症35株 (4.7% ) ,来自各种体液 (胸、腹水、胆汁 ) 5 2株 (7.0 % ) ,来自各种引流液和伤口分泌物 2 5株 (3.4 % ) ,静脉导管13株 (1.8% ) ,其他 15株 (2 .0 % )。革兰阴性杆菌以非发酵菌为主 ,其中铜绿假单胞菌 135株 (18.2 % )、嗜麦芽窄食单胞菌 38株 (5 .1% )、不动杆菌属 37株 (4.9% )及其他非发酵菌 5 7株 (7.7% ) ,其次大肠埃希菌 91株 (12 .3% )、肺炎克雷伯菌 5 3株 (7.2 % )、肠杆菌属 33株 (4.5 % )、其他肠杆菌科 17株 (2 .3% )。铜绿假单胞菌对亚胺培南的耐药率达 4 1.0 % ,呈多重耐药 ,阴沟肠杆菌对头孢他啶、氨曲南的耐药率达 6 0 .0 %、73.3% ,大肠埃希菌、肺炎克雷伯菌产超广谱β-内酰胺酶 (ESBL s)的发生率分别是 4 1.0 %、4 5 .0 % ,亚胺培南? 相似文献