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101.
Richard K. Simpson Jr. Charles F. Contant Claudia S. Robertson J. Clay Goodman 《Neurological research》2013,35(6):367-372
AbstractA model of graded spinal cord injury using ischaemia has been developed by using balloon occlusion of the abdominal aorta in rabbits. This model has been used to test pharmacological agents thought to provide protection against spinal cord injury based on changes in corticomotor evoked potentials (CMEPs). These highly reproducible signals are percutaneously recorded from the spinal cord in response to cortical stimulation and accurately reflect the degree of residual spinal cord function. The present study focused on the power spectra of CMEPs to clarify alterations in post-injury signals. This added dimension of previously unreported CMEP analysis will augmentfuture applications of the current model. [Neurol Res 1993; 15: 367-372] 相似文献
102.
To listen to brain activity as a piece of music,we previously proposed scale-free brainwave music(SFBM)technology,which translated the scalp electroencephalogram(EEG)into musical notes according to the power law of both the EEG and music.In this study,the methodology was further extended to ensemble music on two channels from the two hemispheres.EEG data from two channels symmetrically located on the left and right hemispheres were translated into MIDI sequences by SFBM,and the EEG parameters modulated the pitch,duration and volume of each note.Then,the two sequences were filtered into an ensemble with two voices:the pentatonic scale(traditional Chinese music)or the heptatonic scale(standard Western music).We demonstrated differences in harmony between the two scales generated at different sleep stages,with the pentatonic scale being more harmonious.The harmony intervals of this brain ensemble at various sleep stages followed the power law.Compared with the heptatonic scale,it was easier to distinguish the different stages using the pentatonic scale.These results suggested that the hemispheric ensemble can represent brain activity by variations in pitch,tempo and harmony.The ensemble with the pentatonic scale sounds more consonant,and partially reflects the relations of the two hemispheres.This can be used to distinguish the different states of brain activity and provide a new perspective on EEG analysis. 相似文献
103.
《Global public health》2013,8(9):1078-1091
Previous research suggests that care-seeking in rural northern Ghana is often governed by a woman's husband or compound head. This study was designed to explore the role grandmothers (typically a woman's mother-in-law) play in influencing maternal and newborn healthcare decisions. In-depth interviews were conducted with 35 mothers of newborns, 8 traditional birth attendants and local healers, 16 community leaders and 13 healthcare practitioners. An additional 18 focus groups were conducted with stakeholders such as household heads, compound leaders and grandmothers. In this region, grandmothers play many roles. They may act as primary support providers to pregnant mothers, care for newborns following delivery, preserve cultural traditions and serve as repositories of knowledge on local medicine. Grandmothers may also serve as gatekeepers for health-seeking behaviour, especially with regard to their daughters and daughters-in-law. This research also sheds light on the potential gap between health education campaigns that target mothers as autonomous decision-makers, and the reality of a more collectivist community structure in which mothers rarely make such decisions without the support of other community members. 相似文献
104.
105.
目的探讨新生儿经腹手术中高频电刀适宜切割和凝血的输出功率。方法新生儿外科固定副主任医师主刀经腹手术患儿46例,设置高频电刀输出功率为切割15W,凝血15W。应用序贯法调整输出功率梯度,设定输出功率梯度为1W。若前一例输出功率出现切凝效果不佳,则下一例患者升高一个输出功率梯度;若前一例输出功率出现焦粘组织,则下一例患者降低一个输出功率梯度。将切凝效果不佳与焦粘组织的功率中点设为平衡点,计算所有平衡点高频电刀输出功率的平均值。结果新生儿经腹手术高频电刀切割的输出功率95%可信区间为(14.24±2.16)W、凝血的输出功率95%可信区间为(16.68±2.52)W。结论新生儿经腹手术高频电刀切割的输出功率平均值为14W,凝血的输出功率平均值为16W。 相似文献
106.
《Journal of neurotherapy》2013,17(4):45-71
ABSTRACT Background. A sample of 27 patients with brain injury distributed in five clinical classes was examined for pre- and post-treatment symptoms and associated power spectra. Methods. Changes in electroencephalographic (EEG) compressed spectral arrays were analyzed with respect to the rate of rehabilitation and correlated with a checklist of symptoms for each patient and the group as a whole. Results. Targeted decreases in slower (3–7 Hz) and higher (24–32 Hz) frequencies, and EMG (70–90 Hz), and increases of alpha (8–12 Hz) and mid-range beta frequencies (15–18 Hz) were achieved following Neuro-BioFeedback (NBF) treatment using positive reward tones and a simultaneous visual reward. The impact of gender and age class influence was assessed against treatment results. Single lead EEG power spectra changes were analyzed for hemispherectomized patients, stroke, car accident and trauma patients. A common EEG pattern was observed for a group of patients exhibiting vertigo with two subgroups in which vertigo resolved or did not resolve showing EEG differences. Conclusions. EEG NeuroBioFeedback can successfully treat patients with brain injury with highly clinically-meaningful clinical results. Changes in Cz power spectra generally occur, but do not always immediately follow resolution of symptoms. Since EEG-NBF is limited to recording cortical surface potentials, it is possible that changes induced by the treatment which result in clinical changes may not always be reflected at the cortical surface and hence may not be available for recording and analysis there, despite subcortical integration. 相似文献
107.
We analyzed individual and program characteristics associated with participation in an Information and Communication Technologies (ICT)-based substance use preventive intervention in Uruguay, South America. The intervention was directed at ninth- and tenth-grade students in 10 private schools in Montevideo. Participation in the program was non-mandatory and effective participation rates were low. We found that individual characteristics, such as prior heavy engagement with alcohol and opportunity costs of time, were associated with the decision to participate. We also found that sending the participants periodic reminders via e-mail and short message service (SMS) text messages had a positive impact on participation. The lessons from this intervention suggest that participation in non-mandatory Web-based programs aimed at preventing substance use among adolescents could be substantially improved with a more structured, mandatory, and longer intervention. 相似文献
108.
109.
《Acta odontologica Scandinavica》2013,71(6):541-546
Abstract Objective. The purpose of this in vitro study was to evaluate the influence of different power outputs of a carbon dioxide (CO2) laser on shear bond strength of resin cement to zirconium dioxide-based ceramic. Materials and methods. Fifty zirconium dioxide core specimens (10 mm diameter and 2 mm thickness) were produced and they were embedded in the centers of auto-polymerizing acrylic resin blocks. Ten specimens served as control and no surface treatment was applied. Subsequently specimens were randomly divided into four groups, each containing 10 specimens for surface treatment with CO2 laser with different output power; laser treated with 2 W (Group 2 W), 3 W (Group 3 W), 4 W (Group 4 W) and finally 5 W (Group 5 W). Fifty composite resin discs were fabricated and cemented with adhesive resin cement to the specimen surfaces. A universal test machine was used for shear bond strength test at a crosshead speed 1 mm/min. Data were statistically analyzed by one-way analyses of variance (ANOVA) with Post-Hoc Tukey tests (α = 0.05). Results. It was found that the shear bond strength values were affected by power outputs of laser (p < 0.05). Highest shear bond strength values were obtained with group 2 W (21.0 ± 2.7). Lowest values were obtained with group 5 W (14.4 ± 1.6). Conclusion. The current study revealed that there was a relationship between laser output power and shear bond strength for zirconium dioxide ceramics. However, output power of the laser and the energy level is a critical factor on micromechanical retention. 相似文献
110.
《International journal of food sciences and nutrition》2013,64(3):239-249
The stem, leaf, and root of Tinospora cordifolia (willd.) have been highly exploited for medicinal preparations; however, the nutritional and nutraceutical potential of its attractive red berries (fruits) have not so far been studied. Pigments, berberine (107.0 mg/100 g) and lycopene (50.8 mg/100 g), were identified in the deseeded fruit. Total phenol content in the fruit was 3.2 mg gallic acid equivalent/g. The IC50 of DPPH√ (82, and 468 ppm) and OH√ (100, and 1,000 ppm) scavenging activity, and the EC50 of reducing power (2,616, and 1,472 ppm) of hexane and methanol extracts, respectively, were observed. Oxygen radical absorbance capacities of the fruit extracts (150 and 300 ppm) were 1,107 and 2,614 μM trolox equivalent/g, respectively. Nutrient composition including carbohydrate (18.4%), proteins (1.5%), lipids (6%) of which ~62% was unsaturated fatty acids, vitamins like ascorbic acid (0.24 μg), niacin (0.7 mg), and tocopherols (2.4 mg) in 100 g fruits were determined. Potassium content was 1.2 g/100 g dry tissue of berries. These findings show that components of T. cordifolia fruit could be bioactive and used in food, pharmaceutical, and cosmetics. 相似文献