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Nguyen Thoa C Witter Dick J Bronkhorst Ewald M Truong Nhan B Creugers Nico HJ 《BMC oral health》2010,10(1):1-11
Background
Dental caries is one of the primary causes of tooth loss among adults. It is estimated to affect a majority of Americans aged 55 and older, with a disproportionately higher burden in disadvantaged populations. Although a number of treatments are currently in use for caries prevention in adults, evidence for their efficacy and effectiveness is limited.Methods/Design
The Prevention of Adult Caries Study (PACS) is a multicenter, placebo-controlled, double-blind, randomized clinical trial of the efficacy of a chlorhexidine (10% w/v) dental coating in preventing adult caries. Participants (n = 983) were recruited from four different dental delivery systems serving four diverse communities, including one American Indian population, and were randomized to receive either chlorhexidine or a placebo treatment. The primary outcome is the net caries increment (including non-cavitated lesions) from baseline to 13 months of follow-up. A cost-effectiveness analysis also will be considered.Discussion
This new dental treatment, if efficacious and approved for use by the Food and Drug Administration (FDA), would become a new in-office, anti-microbial agent for the prevention of adult caries in the United States.Trial Registration Number
NCT00357877 相似文献5.
Ellen M. H. Selten Rinie Geenen Henk J. Schers Frank H. J. van den Hoogen Roelien G. van der Meulen-Dilling Willemijn H. van der Laan Marc W. Nijhof Cornelia H. M. van den Ende Johanna E. Vriezekolk 《International journal of behavioral medicine》2018,25(2):198-206
Purpose
Patients’ beliefs about treatment modalities for knee and hip osteoarthritis (OA) will underlie their treatment choices. Based on the Theory of Planned Behavior, it is hypothesized that patients’ beliefs, subjective norm, and perceived behavioral control guide their treatment choices. Also, symptom severity and one’s inherent tendency to approach or avoid situations are assumed to play a role. The objective of this study was to test whether these variables were associated with intended treatment choices in knee and hip OA.Methods
Patients with knee and hip OA were randomly selected from hospital patient records. They completed the Treatment beliefs in OsteoArthritis questionnaire to assess positive and negative treatment beliefs regarding five treatment modalities: physical activities, pain medication, physiotherapy, injections, and arthroplasty. Other measures were intention, subjective norm, perceived behavioral control (ASES), symptom severity (WOMAC), and the person’s general tendency to approach or avoid situations (RR/BIS scales). Three models were tested using path analyses to examine the hypothesized associations.Results
Participants were 289 patients. Positive treatment beliefs and subjective norm were consistently associated with intended treatment choice across all treatment modalities. Negative treatment beliefs were associated with intended treatment choices for pain medication and arthroplasty. Other associations were not significant.Conclusions
This is the first study testing the Theory of Planned Behavior in the context of treatment choices in OA. Findings suggest that foremost positive beliefs about treatment modalities and the norms of one’s social environment guide a specific treatment choice. Unexpectedly, symptom severity was not related to intended treatment choices.6.
目的:人体助行带为一种随身佩带的动力装置,应用遥测肌电技术测定和分析自行研制的人体助行带的生物力学作用机制。方法:实验于2005-12/2006-06在天津体育大学运动生物力学实验室进行。选取天津市天津医院30名受试对象,均对本实验知情同意。按照生物力学的测试要求,首先对受试者进行5次以上行走状态下的遥测肌电测定,然后在同等条件下对受试者佩带助行带实施对照研究。实验采用的助行带为自行研制的,由腰至足以双层弹力带作为动力装置的弹性结构。结果:行走摆动相大腿肌肌电:佩带助行带后肌内侧肌、肌二头肌、半腱肌肌电高于佩带前(P<0.01)。支撑相小腿肌肌电:佩带助行带后胫前肌、腓骨长肌、腓肠肌肌电高于佩带前(P<0.01)。结论:通过弹力带施加于下肢的外部载荷,能够起到增强下肢肌电以及产生助行的生物力学功效。 相似文献
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目的:探讨儿童围术期镇痛的必要性及椎管阻滞应用的可行性。方法:以"pediatric patient,analgesia,perioperat"为检索词,检索1990-01/2004-12PubMed数据库关于儿童围术期镇痛的文献,选取随机对照研究设计的文献,对其中14篇进行归纳总结。结果:①疼痛的并发症:儿童围术期的疼痛不但与成人一样影响血流动力学稳定、增加术后并发症和死亡率;还可导致慢性疼痛综合征、注意力不集中、学习能力下降等并发症。②多模式镇痛:疼痛治疗可在形成疼痛的转化、传导、整合、认知4个水平采取措施。复合使用多种作用机制不同的药物可以减少每种药物的用量,减少副作用,取得更好的疗效。采用超前镇痛,在伤害性刺激之前施行疼痛治疗,只有当伤害性刺激完全被阻断时,超前镇痛的优势才能显现出来,而且阻断时效应该比术后急性疼痛时间长。③疼痛的评价:目前临床常用评分方法是NIPS(neonatalinjurypainscale)评分系统,包括面部表情、哭吵、呼吸形式、上下肢运动和觉醒状态5个指标。评分越低说明疼痛越轻。④围术期椎管阻滞镇痛治疗:重点介绍硬膜外技术、硬膜外常用药物及剂量、适应证、并发症等。结论:有必要对儿童施行围术期镇痛,椎管阻滞是儿童围术期镇痛一种切实可行的方法。 相似文献
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HJ Alter ; GE Tegtmeier ; BW Jett ; S Quan ; JW Shih ; WL Bayer ; A Polito 《Transfusion》1991,31(8):771-776
Samples from prospectively followed recipients, their respective donors, and a cohort of random donors were used to evaluate the specificity and efficacy of a recombinant immunoblot assay (RIBA) as an adjunct to anti-hepatitis C virus (HCV) testing by enzyme immunoassay (EIA). RIBA reacted (RIBA+) in 100 percent of patients who developed hepatitis associated with anti-HCV seroconversion documented by EIA and in 100 percent of the EIA-positive (EIA+) donors implicated in these cases. In contrast, RIBA reacted in none of 10 recipients who were EIA+ but did not develop hepatitis, in none of 7 EIA+ patients with hepatitis B or cytomegalovirus infection, in 33 percent of EIA+ donors who were not implicated in hepatitis transmission, and in 37 percent of EIA+ random donors. Hence, the vast majority of EIA+ individuals who have ancillary evidence of HCV infection react on RIBA, whereas the majority of EIA+ individuals in low-risk settings do not react (RIBA-negative, or RIBA-). There was a strong association between RIBA reactivity and the presence of a surrogate marker (elevated alanine aminotransferase [ALT] and/or antibody to hepatitis B core antigen); 43 percent of RIBA+ implicated donors had a surrogate marker as compared to none of 14 EIA+, RIBA- donors. Among EIA+ random donors, 77 percent of those with a surrogate marker were RIBA+, as compared with 29 percent of those without a surrogate marker. In addition, in EIA+ donors, RIBA reactivity correlated with the extent of ALT elevation; 86 percent of those with an ALT greater than 135 IU per L were RIBA+ compared with 18 percent of those with an ALT less than 30 IU per L.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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人脂肪干细胞复合脱细胞软骨基质支架在生物反应器中构建组织工程软骨 总被引:5,自引:5,他引:5
目的:观察人脂肪干细胞复合脱细胞软骨基质支架在生物反应器中初步构建组织工程软骨的可行性。方法:实验于2005-04/2006-05在解放军总医院骨科研究所完成。脂肪组织和关节软骨均来自膝关节置换术中切除的组织,并经患者知情同意。关节软骨冻干后经粉碎机粉碎,过筛,选取25~38μm大小的软骨微粒。在样品中先加入2.5g/L胰蛋白酶,37℃消化24h,再加入1%Triton X-100震荡72h。将软骨微粒和蒸馏水按1∶3的比例混合后滴加在模板中,置入冷冻干燥机冻干后行紫外线交联。紫外线照射8h完成。最后经25kGy 60Co辐照灭菌完成支架制备。取膝关节置换术中切除的髌下脂肪垫,酶消法获得脂肪干细胞,扩增后复合于脱细胞软骨基质制成圆柱状三维支架上(细胞密度5×1010L-1),置于生物反应器中进行诱导培养,同时设静态培养组作为对照,3周后观测大体形态和组织学形态变化,同时进行组织化学(包括番红花O,阿利新蓝染色)和Ⅱ型胶原免疫组织化学分析。结果:生物反应器组诱导培养3周苏木精-伊红染色显示支架结构消失,只有中心区域残存少量支架结构;静态培养组支架结构尚存在,有少量基质分泌。番红花O染色显示生物反应器组细胞外有大量蛋白聚糖沉积,阿利新蓝染色表明有软骨特异性蛋白多糖的聚集;而静态培养组只有部分区域染色且淡于生物反应器组。Ⅰ型胶原免疫组化的结果显示,在生物反应器组细胞能够合成大量软骨细胞特异性胶原成分,而静态培养组呈弱阳性。结论:生物反应器培养明显促进了脂肪干细胞的增殖与软骨分化,是体外构建组织工程软骨的良好方法。 相似文献
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Neurophysiological methods for the assessment of spasticity: The Hoffmann reflex, the tendon reflex, and the stretch reflex 总被引:1,自引:0,他引:1
Purpose: To review the literature concerning neurophysiological methods to assess spasticity with respect to mechanisms and methodology, and to describe the three most commonly used methods: the Hoffmann reflex (H-reflex), the Tendon reflex (T-reflex), and the Stretch Reflex (SR). Method: A systematic internet database search was performed to identify neurophysiological measurement methods of spasticity. A systematic exclusion procedure resulted in 185 included references, completed by additional informal search. For this paper, information about the H-, T- and stretch reflexes was extracted from these references. Results: Although the reflexes are basically monosynaptic, there are many supraspinal pathways which modulate the responses in terms of their amplitude and latency. As a consequence the methods are sensitive to a considerable number of experimental conditions and are characterized by a moderate reliability and sensitivity. Correlations with other (i.e. biomechanical, neurophysiological or clinical) spasticity assessment parameters are moderate to poor. Standardised and broadly accepted protocols are still largely lacking preventing an effective exchange of knowledge. Conclusions: The clinical and experimental use of the three methods is restricted due to moderate reliability and sensitivity. It is recommended to perform combined neurophysiological - biomechanical assessment of spasticity during active, functional movement. 相似文献