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91.
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92.
虚拟现实技术在运动康复中的应用 总被引:1,自引:3,他引:1
目的:介绍虚拟现实技术在运动功能障碍的康复性训练领域的应用和新发展,讨论虚拟现实技术应用于运动康复的优势和前景。资料来源:应用计算机检索外文期刊PsycINFO和PubMed数据库1996/2006与虚拟现实技术在康复训练中应用相关的文章,检索语种为“English”,检索词为“motor rehabilitation,virtual reality”。检索中文期刊CNKI数据库1996/2006相关的文献,检索语种为中文,检索词为“康复,虚拟现实”。资料选择:根据摘要和关键词对资料进行初选,选择全面介绍虚拟现实技术的文章,以及近几年将虚拟现实技术应用于空间感知障碍和运动功能受损患者康复训练的实验研究报告。资料提炼:在上述3个数据库中分别检索到相关英文文献121篇,以及中文文献21篇,按上述标准纳入18篇,再继续搜索已有文献引用和被引用的参考文献,最后得到相关的中英文文献30篇。资料综合:30篇文献中,4篇文章详细介绍了虚拟现实技术在运动康复领域的应用,26篇实验报告了应用虚拟现实对受损的运动功能进行康复性训练的成效。按照运动康复的种类将研究报告分为4类:平衡和姿态训练、行走训练、上下肢康复训练和日常生活技能训练。通过模仿练习,感知运动受损的患者可以在虚拟环境中完成针对性训练任务,学会运动技能。在虚拟环境中习得的运动技能可以迁移到现实世界的真实任务中。结论:与传统康复训练方法相比,虚拟现实具有更安全、更有趣、针对性强、康复速度快、疗效好等优势。作为一种有效的运动康复技术手段,虚拟现实技术有很好的发展前景。 相似文献
93.
Platelet adhesion and thrombus formation on subendothelium in platelets deficient in glycoproteins IIb-IIIa, Ib, and storage granules 总被引:22,自引:1,他引:22
Patients whose platelets are deficient in glycoprotein (GP) Ib, IIb- IIIa (thrombasthenia), or granule substances (storage pool deficiency, SPD) were studied to define further the properties of platelets that mediate platelet adhesion and thrombus formation on subendothelium. Both nonanticoagulated and citrated blood were exposed to everted, de- endothelialized rabbit vessel segments under controlled flow conditions and shear rates varying from 650 to 3,300 sec-1. Morphometry was used to measure platelet thrombus dimensions and the percentage of the subendothelial surface covered with contact (C) or spread (S) platelets. Adhesion was defined as C + S. The results in SPD demonstrated (1) reduced thrombus dimensions in delta-SPD (pure dense granule deficiency) in proportion to the magnitude of the dense granule defect; (2) an even greater reduction in thrombus dimensions in patients with combined deficiencies of alpha and dense granules (alpha delta-SPD); and (3) impaired platelet adhesion at several conditions in alpha delta-SPD and, in delta-SPD, a hematocrit-dependent impairment of adhesion in citrated blood at 2,600 sec-1. In thrombasthenia, platelets were present as a monolayer on the subendothelial surface in both nonanticoagulated and citrated blood, indicating an absolute requirement for GPIIb-IIIa in promoting platelet-platelet interaction at all shear rates and perfusion times. Two types of abnormalities in platelet-vessel wall interactions were observed. In nonanticoagulated blood, the percentage of platelets in the C phase was consistently increased at all shear rates, but C + S values were normal. These observations indicate that platelets deficient in GPIIb-IIIa do not spread normally on the subendothelial surface exposed to nonanticoagulated blood. With citrated blood, the C + S value in thrombasthenia was reduced at both 800 and 2,600 sec-1, as in von Willebrand's disease, and a similar degree of reduction (about 50%) was observed in normal blood treated with a monoclonal antibody to GPIIb- IIIa. The findings, together with theoretical considerations, are consistent with an hypothesis that GPIIb-IIIa mediates the spreading of platelets on subendothelium following the initial attachment through GPIb and that GPIIb-IIIa may be considered an adhesion site on the platelet membrane. Abnormalities of GPIIb-IIIa may, depending on the conditions of study, result in either increased values of C platelets or decreased values of C + S. The results of the study further suggest that a complex interaction of platelet granule factors and membrane GP mediate platelet adhesion and thrombus formation. 相似文献
94.
目的:为获得大量的9,10-二羟基硬脂酸(Dihydroxy Stearic Acid,DHSA),应用质谱、红外光谱及核磁共振解析验证合成物为DHSA。
方法:实验于2007-01/05在解放军总医院营养科实验室完成。在烧瓶中加入油酸后,再加入甲酸、过氧化氢,并不断搅拌。在整个反应过程中维持反应温度在40℃,反应四五小时后,反复水洗油层并收集。在油层中加入3mol/L NaOH溶液25mL,于100℃水浴加热1h,趁热加入3mol/L HCl50mL,剧烈搅拌,析出白色沉淀。用水反复清洗使清洗液pH值为中性,收集沉淀物。在沉淀物中加入体积分数为0.95的乙醇10mL,加热溶解,抽滤,将滤液于0℃析出结晶,抽滤,将抽滤物用体积分数为0.95的乙醇10mL加热溶解,于0℃结晶,抽滤。同样方法再结晶2次,最后得到白色结晶物,晾干,收率68.8%。将结晶物分别上FTS-65A红外光谱仪、ISONS EA1108型元素分析仪,Varian INOVA 600型核磁共振仪,安捷伦XCR-trap液相质谱(LC-MS)联用仪进行分析和结构鉴定。
结果:①LC-MS分析提示合成的DHSA经过多次重结晶后,纯度较高,可达95%。MS分析提示DHSA相对分子质量为315.1,与理论值316.48相近。②DHSA元素分析实验值C68.78%,H11.53%,与理论值C68.77%,H11.58%接近。③红外光谱分析提示DHSA为含有两个羟基的十八碳长链脂肪酸。④核磁共振的氢谱和碳谱均证实合成的化合物为9,10-二羟基十八碳脂肪酸。
结论:合成的DHSA经过3次重结晶后,纯度可95%以上,质谱、红外光谱及核磁共振解析结果证实合成的化合物是9,10-二羟基硬脂酸。 相似文献
95.
Marrow transplantation with or without donor buffy coat cells for 65 transfused aplastic anemia patients 总被引:4,自引:3,他引:4
Storb R; Doney KC; Thomas ED; Appelbaum F; Buckner CD; Clift RA; Deeg HJ; Goodell BW; Hackman R; Hansen JA; Sanders J; Sullivan K; Weiden PL; Witherspoon RP 《Blood》1982,59(2):236-246
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%). 相似文献
96.
97.
Impaired and enhanced attentional function in children with attention deficit/hyperactivity disorder 总被引:3,自引:0,他引:3
BACKGROUND: The symptom domain of inattention in attention deficit/hyperactivity disorder (ADHD) suggests that there are neuropsychological fields of attention in which subjects with ADHD express deficits. However, studies using differentiated neuropsychological attentional tests in ADHD are lacking. METHOD: A consecutive series of 35 subjects with ADHD aged 9-12 years were assessed on a computer-driven neuropsychological test battery for attentional functions. Their performance was classified according to the data of a normative sample of 187 healthy subjects aged 9-12 years, and compared with the performance of 35 matched healthy control subjects. RESULTS: According to normative data, most ADHD subjects performed on all attentional measures within the normal range. Comparisons with the control group revealed that ADHD subjects reacted faster on all attentional tests, yielding statistical significance for the Go/No go test and the Divided Attention test. They also performed with significantly fewer errors on the Divided Attention test. On the Go/No go test, Visual Scanning test and Attentional Shift test ADHD subjects committed significantly more errors than control subjects. CONCLUSIONS: Our results suggest a differential pattern rather than a deficit pattern of attentional functions in ADHD. It is suggested that the more rapid response style of ADHD subjects leads to a more erroneous performance in self-paced attentional tasks and to a better performance in externally paced attentional tasks. However, neuropsychological tests of attention do not contribute to the clinical diagnosis of ADHD. 相似文献
98.
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
99.
Clift RA; Buckner CD; Thomas ED; Bensinger WI; Bowden R; Bryant E; Deeg HJ; Doney KC; Fisher LD; Hansen JA 《Blood》1994,84(6):2036-2043
A prospective randomized study was conducted comparing two conditioning regimens for the treatment of patients with chronic myeloid leukemia in chronic phase by marrow transplantation from HLA identical siblings. Sixty-nine patients received 60 mg/kg of cyclophosphamide on each of 2 successive days followed by 6 fractions of total body irradiation each of 2.0 Gy (CY-TBI), and 73 patients received 16 mg/kg of busulfan delivered over 4 days followed by 60 mg/kg CY on each of 2 successive days (BU-CY). There was no significant difference between the CY-TBI and the BU-CY groups in the 3-year probabilities of survival (0.80 for both), relapse (0.13 for both), or event-free survival (CY-TBI, 0.68; BU-CY, 0.71) or in speed of engraftment or incidence of venocclusive disease of the liver. The 4-year probabilities of survival and event- free survival for patients transplanted within 1 year of diagnosis were 0.86 and 0.72, respectively, for each group. Significantly more patients in the CY-TBI group experienced major creatinine elevations. There was significantly more acute graft-versus-host disease in the CY- TBI group. Fever days, positive blood cultures, hospitalizations, and inpatient hospital days were significantly more common in the CY-TBI group than in the BU-CY group. In conclusion, the BU-CY regimen was better tolerated than, and associated with survival and relapse probabilities that compare favorably with, the CY-TBI regimen. 相似文献
100.
A 59-year-old white woman with temporal arteritis developed progressive renal failure. Renal biopsy results showed focal and segmental necrotizing glomerulonephritis; furthermore, giant cells were present in the destructed vessel walls. Immunosuppressive therapy did not prevent terminal renal failure. This case shows that renal involvement may be a feature of temporal arteritis. 相似文献