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101.
Neerja Bharti Indu Bala Vidhya Narayan Gurpreet Singh 《Acta anaesthesiologica Taiwanica》2013,51(1):10-13
Study objectiveGabapentin is an inhibitory neurotransmitter of the central nervous system. This prospective randomized double-blind study was conducted to evaluate the effects of gabapentin on intraoperative propofol requirements, hemodynamic variables, and postoperative pain relief in breast cancer patients.Materials and methodsForty adult females of the American Society of Anesthesiologists (ASA) Grade I-II physical status, undergoing total mastectomy for breast cancer were included. Patients were randomly allocated into two groups. Two hours prior to surgery the gabapentin group received gabapentin 600 mg and the control group received placebo. Anesthesia was induced with intravenous fentanyl, propofol, and vecuronium, and maintained with propofol infusion titrated according to the bispectral index. Postoperative analgesia was provided with intramuscular diclofenac sodium and intravenous morphine on demand.ResultsThe intraoperative propofol consumption was significantly less in the gabapentin group as compared with the control group (p = 0.009), whereas there was no difference in fentanyl and vecuronium requirements. Patients in the gabapentin group had lower pain scores at 30 minutes, 1 hour, and 2 hours postoperatively (p < 0.001). The postoperative morphine consumption was also less in the gabapentin group compared with the control group (p = 0.006). No significant adverse effects were noticeable.ConclusionPreoperative administration of gabapentin reduced intraoperative propofol requirements and postoperative analgesic consumption in breast cancer patients undergoing total mastectomy. 相似文献
102.
S. Hassan A. Akbari David D. Limbrick Jr. David H. Kim Prithvi Narayan Jeffrey R. Leonard Matthew D. Smyth Tae Sung Park 《Child's nervous system》2013,29(7):1143-1154
Purpose
Variation exists in the surgical methods employed for decompression of Chiari II malformation (CIIM), yet an evaluation of these techniques has not been performed. The purpose of this study was to assess the efficacy of bony decompression (cervical laminectomy alone versus suboccipital craniectomy with laminectomy) with or without dural augmentation for the treatment of symptomatic CIIM.Methods
Clinical records of children 0–18 years of age who underwent surgical repair of myelomeningocele or CIIM decompression at St. Louis Children’s Hospital (SLCH) from 1990–2011 were reviewed. Signs/symptoms prompting decompression, surgical technique, operative parameters, and clinical outcomes were recorded for analysis.Results
Thirty-three subjects were treated at SLCH for CIIM decompression. Twenty-six subjects underwent bony decompression only (21 cervical laminectomy alone, 5 suboccipital craniectomy?+?cervical laminectomy) while seven underwent bony decompression with upfront dural augmentation (three cervical laminectomy alone, four suboccipital craniectomy?+?cervical laminectomy). Median follow up was 5.0 years (range, 3 months–19 years). Symptomatic improvement was noted in 20/33 subjects (60.6 %). Sixty-two (61.5 %) percent of children who underwent bony decompression had symptomatic improvement, compared with 57.1 % of those with upfront dural augmentation (p?=?0.37). Estimated blood loss, operative time, and length of perioperative hospital stay appeared lower in the bony decompression group but were not statistically different in this limited cohort.Conclusions
The results from this series suggest that bony CIIM decompression via tailored cervical laminectomies alone, without suboccipital craniectomy or upfront dural augmentation, is a reasonable initial management approach for decompression of symptomatic CIIM. 相似文献103.
Senthil Kumar Subramanian Giriwar Singh Gaur Sunil K. Narayan 《Annals of Indian Academy of Neurology》2013,16(4):614-618
Context:
Visual evoked potentials are useful in investigating the physiology and pathophysiology of the human visual system. Flash visual evoked potential (FVEP), though technically easier, has less clinical utility because it shows great variations in both latency and amplitude for normal subjects.Aim:
To study the effect of eye closure, low luminance, and monochromatic stimulation on the variability of FVEPs.Subjects and Methods:
Subjects in self-reported good health in the age group of 18-30 years were divided into three groups. All participants underwent FVEP recording with eyes open and with white light at 0.6 J luminance (standard technique). Next recording was done in group 1 with closed eyes, group 2 with 1.2 and 20 J luminance, and group 3 with red and blue lights, while keeping all the other parameters constant. Two trials were given for each eye, for each technique. The same procedure was repeated at the same clock time on the following day.Statistical Analysis:
Variation in FVEP latencies between the individuals (interindividual variability) and the variations within the same individual for four trials (intraindividual variability) were assessed using coefficient of variance (COV). The technique with lower COV was considered the better method.Results:
Recording done with closed eyes, 0.6 J luminance, and monochromatic light (blue > red) showed lower interindividual and intraindividual variability in P2 and N2 as compared to standard techniques.Conclusions:
Low luminance flash stimulations and monochromatic light will reduce FVEP latency variability and may be clinically useful modifications of FVEP recording technique.Key Words: Eye closure, flash visual evoked potentials, latency variability, luminance, monochromatic light, visual evoked potentials 相似文献104.
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106.
Buck BJ Kerman IA Burghardt PR Koch LG Britton SL Akil H Watson SJ 《Neuroscience letters》2007,421(2):178-183
Although alterations in the function of the neurotransmitter system have been implicated in the pathology of Alzheimer's disease (AD), the mechanisms that underlie this pathological change are not well understood. Beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) is a key protease in the generation of beta-amyloid, an important trigger protein in the pathogenesis of AD. The expression and activity of BACE1 are increased in the brains of sporadic AD patients, and a role for BACE1 in neurotransmission has been suggested recently. This study examines whether BACE1 plays a role in regulated exocytosis in PC12 cells. Treatment of PC12 cells with a beta-secretase inhibitor reduced stimulus-dependent secretion of neurotransmitters, suggesting a potential role of BACE1 in regulated exocytosis. Using transfected human growth hormone as a reporter for a regulated secretory pathway in PC12 cells, we found that the transient overexpression of BACE1 increased basal secretion in the absence of a stimulus and reduced stimulus-dependent secretion in intact PC12 cells. In digitonin-permeabilized PC12 cells, an overexpression of BACE1 enhanced the Ca2+-independent and ATP-independent component of the secretory pathway. Furthermore, expression of the glycosylation-deficient mutant of BACE1, BACE1N354Q, led to an elevation of basal secretions over that by BACE1 wild-type, suggesting a role of BACE1 glycosylation in basal secretion. These results demonstrate an unknown role for BACE1 in secretion, and suggest that elevated levels of BACE1 in AD brains may contribute to the altered neurotransmitter pathology of AD through stimulation of spontaneous basal secretion under resting conditions. 相似文献
107.
Vijay Narayan Grace John-Stewart George Gage Gabrielle O’Malley 《Human resources for health》2018,16(1):50
Background
Sierra Leone’s health outcomes rank among the worst in the world. A major challenge is the shortage of primary healthcare workers (HCWs) in rural areas due to especially high rates of attrition. This study was undertaken to determine the drivers of job dissatisfaction and poor retention among Sierra Leone’s rural HCWs.Methods
Interviews were conducted with 58 rural and 32 urban primary HCWs in Sierra Leone’s public health sector, complemented by key informant discussions and review of national policy documents. HCW interviews included (1) semi-structured discussion, (2) questionnaire, (3) card sort about HCW priorities, and (4) free-listing of most pressing challenges and needs. Sampling for HCW interviews was stratified purposive, emphasizing rural HCWs.Results
Among 90 HCWs interviewed, 67% were dissatisfied with their jobs (71% rural vs 52% urban) and 61% intended to leave their post (75% rural vs 38% urban). While working and living conditions and remuneration were significant factors, a major reason for rural HCW disenchantment was their inability to access worker rights, benefits, and advancement opportunities. This was caused by HCWs’ lack of knowledge about human resource (HR) policies and procedures, as well as ambiguity in many policies and inequitable implementation. HCWs reported feeling neglected and marginalized and perceived a lack of transparency. These issues can be attributed to the absence of systems for regular two-way communication between the Ministry of Health and HCWs; lack of official national documents with up-to-date, clear HR policies and procedures for HCWs; pay statements that do not provide a breakdown of financial allowances and withholdings; and lack of HCW induction.Conclusions
HCWs in Sierra Leone lacked accurate information about entitlements, policies, and procedures, and this was a driver of rural HCW job dissatisfaction and attrition. System-oriented, low-cost initiatives can address these underlying structural causes in Sierra Leone. These issues likely apply to other countries facing HCW retention challenges and should be considered in development of global HCW retention strategies.108.
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