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61.

BACKGROUND CONTEXT

Although 40% of adolescent idiopathic scoliosis (AIS) patients present with chronic back pain, the pathophysiology and underlying pain mechanisms remain poorly understood. We hypothesized that development of chronic pain syndrome in AIS is associated with alterations in pain modulatory mechanisms.

PURPOSE

To identify the presence of sensitization in nociceptive pathways and to assess the efficacy of the diffuse noxious inhibitory control in patients with AIS presenting with chronic back pain.

STUDY DESIGN

Cross-sectional study.

PATIENT SAMPLE

Ninety-four patients diagnosed with AIS and chronic back pain.

OUTCOME MEASURES

Quantitative sensory testing (QST) assessed pain modulation and self-reported questionnaires were used to assess pain burden and health-related quality of life.

METHODS

Patients underwent a detailed pain assessment using a standard and validated quantitative sensory testing (QST) protocol. The measurements included mechanical detection thresholds (MDT), pain pressure threshold (PPT), heat pain threshold (HPT), heat tolerance threshold (HTT), and a conditioned pain modulation (CPM) paradigm. Altogether, these tests measured changes in regulation of the neurophysiology underlying the nociceptive processes based on the patient's pain perception. Funding was provided by The Louise and Alan Edwards Foundation and The Shriners Hospitals for Children.

RESULTS

Efficient pain inhibitory response was observed in 51.1% of patients, while 21.3% and 27.7% had sub-optimal and inefficient CPM, respectively. Temporal summation of pain was observed in 11.7% of patients. Significant correlations were observed between deformity severity and pain pressure thresholds (p=.023) and CPM (p=.017), neuropathic pain scores and pain pressure thresholds (p=.015) and temporal summation of pain (p=.047), and heat temperature threshold and pain intensity (p=.048).

CONCLUSIONS

Chronic back pain has an impact in the quality of life of adolescents with idiopathic scoliosis. We demonstrated a high prevalence of impaired pain modulation in this group. The association between deformity severity and somatosensory dysfunction may suggest that spinal deformity can be a trigger for abnormal neuroplastic changes in this population contributing to chronic pain syndrome.  相似文献   
62.
生物安全柜是重要的一级屏障设备,适当的控制方式对生物安全柜的防护能力是很重要的。文中主要介绍了生物安全柜的控制要点和几种控制方式及其特点。  相似文献   
63.
深圳市全人口结核病控制实施效果评价   总被引:1,自引:0,他引:1  
目的 研究深圳市实施包含非户籍人口在内的全人口结核病控制模式。方法 在全人口中推行以发现和彻底治疗传染性肺结核病为主的现代结核病控制和监测策略。结果 从1993年至2001年,登记涂阳肺结核8483例,治愈率96.3%。肺结核疫情明显下降,深圳市户籍人口涂阳患病率下降55.9%,非户籍人口涂阳患病率下降38.6%。结论 实施全人口结核病控制是必要的、可行的和科学的。  相似文献   
64.
主动呼吸控制技术(ABC)在肺癌放射治疗中的应用   总被引:1,自引:0,他引:1  
王辛  张洪  沈娅丽  徐庆丰  许峰 《中国肿瘤临床》2006,33(24):1414-1417
目的:使用主动呼吸控制技术(aetive brething control,ABC)治疗非小细胞肺癌患者,评价呼吸运动时肺部肿瘤动度的影响及ABC技术的优势和可行性,并评价近期疗效和急性放射反应。方法:选择9例使用ABC技术联合三维造型放疗技术治疗的非小细胞系癌患者进行分析。CT定位扫描时分别采集ABC和自由呼吸(free breath.FB)状态下的图像,评价呼吸运动对肺部肿瘤动度和PTV边界的影响唾弃;并比较两种计划的DVH,放疗剂量为54-60Gy/18-20次。3Gy/次,1次/天,5天/周,定期随访,评价近期疗效及急性放射反应。结果:应用ABC技术后,隔肌的平均位移从FB时的43.5mm(20.0-32.0mm)降低为3.6mm(0.5-72.mm),胸壁的侧方位移从FB时的3.2mm(2.8-4.0mm)降低为1.2mm(0.5-1.6mm).PTV边界可以从FB时的1.5mm减少为0.75cm;肺的V20从21.8%降低为15.0%,减少了30.6%.中位随访6个月时,9例患者中有6例CR,3例PR.急性放射副反应都很轻微,仅为I-II.结论:在肺癌的精确放射治疗中,呼吸动度的影响不可忽视.而ABC系统可以有效的降低呼吸运动时治疗的影响,提高放疗的精确性,减少副反应.,但该系统使用较为复杂,延长了治疗的时间,个别患者不能忍受.  相似文献   
65.
积极治疗节育手术并发症是搞好计划生育的一个重要环节。月经异常是宫内放置节育环的主要并发症,也是节育环停止使用的主要原因。近几年来本人采用消炎痛治疗官内放环后月经异常,取得了良好的效果。  相似文献   
66.
This paper considers a dynamic pricing problem over a finite horizon where demand for a product is a time‐varying linear function of price. It is assumed that at the start of the horizon there is a fixed amount of the product available. The decision problem is to determine the optimal price at each time period in order to maximize the total revenue generated from the sale of the product. In order to obtain structural results we formulate the decision problem as an optimal control problem and solve it using Pontryagin's principle. For those problems which are not easily solvable when formulated as an optimal control problem, we present a simple convergent algorithm based on Pontryagin's principle that involves solving a sequence of very small quadratic programming (QP) problems. We also consider the case where the initial inventory of the product is a decision variable. We then analyse the two‐product version of the problem where the linear demand functions are defined in the sense of Bertrand and we again solve the problem using Pontryagin's principle. A special case of the optimal control problem is solved by transforming it into a linear complementarity problem. For the two‐product problem we again present a simple algorithm that involves solving a sequence of small QP problems and also consider the case where the initial inventory levels are decision variables. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
67.
目的:对采用头皮冠状切口所引发的并发症进行分析,探讨防治策略。方法:对我科2003-01~2006—07应用头皮冠状切口行颅颌面骨折修复重建、颌面部肿瘤切除与缺损修复、先天性颅颌面畸形矫正的221例中发生并发症的40例进行分析总结。结果:18例出现头皮麻木及感觉异常,9例有较宽切口瘢痕,6例出现脱发,4例发生颞窝凹陷,2例发生头皮下血肿,2例出现单侧面神经颞支损伤,1例发生鼻眶区肥厚。结论:头皮冠状切口具有切口隐蔽、面部疤痕不明显,显露充分的优点,但对其并发症也不容忽视。应根据具体情况选择合适的切口类型,术中精细的解剖、神经血管的良好保护以及正确的缝合方法可减少并发症的发生。  相似文献   
68.
A discrete time optimal control for linear time-delay systems is developed to ensure that all closed-loop eigenvalues will lie inside a circular region centred at (β;, 0) with radius α. It is shown that by suitable manipulations the problem can be reduced to a standard discrete time quadratic regulator problem. An illustrative example is included to demonstrate the applicability of the proposed method.  相似文献   
69.
Several studies have demonstrated that a descending dopaminergic pathway innervates the dorsal and the intermediate gray matter of the spinal cord and have suggested that this pathway is involved in pain modulation and in the control of autonomie functions. Other studies have also demonstrated the presence of dopamine (DA) and DA metabolites as well as of DA receptors in the ventral cord. There is also evidence for the implication of DA in the control of motor functions at the spinal level. The occurrence of a dopaminergic innervation in the ventral horn has been, however, disputed until recently. But recent work has demonstrated that the motoneural cell groups in the ventral horn (lamina IX) are a target for descending dopaminergic fibers. In addition, the possibility that DA is a mediator of primary afferent fibers has also been postulated. Finally, the occurrence of dopaminergic cell bodies has been suggested in the spinal cord. This indicates that DA is probably implicated in a complex manner in spinal functions. In the present paper the possible involvement of DA in sensory and in motor functions at spinal level will be discussed in view of neurochemical observations made in polyarthritic rats, in which pain-related behavior and reduction of locomotor activity associated with a marked decrease in mobility, are observed.  相似文献   
70.
A feasibility study was undertaken to evaluate laboratory phlebotomists performing bedside glucose monitoring (BGM) over a 3-month period on a medical and surgical floor. Specific questions included: feasibility of providing testing on a 24-h basis, accuracy, appropriate utilization, effect on patient care, and an analysis of cost. In all, 1975 tests were performed on 114 patients. BGM results were within 15% of the laboratory's result 97% of the time. Patient and physician satisfaction was high. Although the cost of BGM is slightly higher than a laboratory glucose test, its use appeared to reduce the length of hospital stay by 0.47 days. Practical information on initiating a highly successful BGM program is provided.  相似文献   
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