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141.
HC Ciria MS Quevedo LB Cabrales RP Bruzón MF Salas OG Pena TR González DS López JM Flores 《BMC cancer》2004,4(1):87
Background
In vivo studies were conducted to quantify the effectiveness of low-level direct electric current for different amounts of electrical charge and the survival rate in fibrosarcoma Sa-37 and Ehrlich tumors, also the effect of direct electric in Ehrlich tumor was evaluate through the measurements of tumor volume and the peritumoral and tumoral findings. 相似文献142.
目的:通过探讨血卟啉衍生物光动力学效应对人鼻咽癌细胞株CNE2的生物作用,为光动力治疗放、化疗效果较差的鼻咽癌提供理论依据。方法:实验于2005-10/2006-06在南方医科大学南方医院肿瘤生物治疗中心实验室完成。对体外培养的人鼻咽癌细胞株CNE2分为光处理和无光处理各8个实验组及各分别设对照组和空白对照组,实验组分别加入0.5,1.0,1.5,2.0,2.5,3.0,3.5,4.0mg/L血卟啉衍生物100μL,每组设7个复孔;孵育4h,对照组除不加光敏剂外其他与实验组相同,空白对照组只加培养基不加细胞和光敏剂。光处理实验组给予波长为630nm的半导体激光进行照射,照射的功率密度为20mW/cm2,照射能量密度分别为20,10,5,2J/cm2,继续孵育24h,用四唑盐(MTT)比色法测定细胞存活率。细胞存活率(%)=(实验组A值-空白对照组A值)/(对照组A值-空白对照组A值)×100%。每次实验重复3次,取平均值。结果:①血卟啉衍生物与CNE2细胞共同孵育后,采用630nm的半导体激光照射可对其产生杀伤作用,杀伤作用大小与血卟啉衍生物的浓度和激光剂量成正相关(P<0.01),但血卟啉衍生物浓度达2.5mg/L以上时杀伤细胞作用无显著增加。激光能量为20J/cm2,血卟啉衍生物的浓度为2.5mg/L时,其杀伤CNE2细胞的作用最明显。②在加入血卟啉衍生物而无激发光的情况下,血卟啉衍生物对鼻咽癌细胞生存不产生明显影响(P>0.05)。结论:血卟啉衍生物介导的光动力在体外可以对CNE2细胞产生杀伤效应,在一定范围内杀伤作用大小与血卟啉衍生物的浓度和激光剂量成正相关。 相似文献
143.
Jennifer LB Martay Antony JR Palmer Neil K Bangerter Stuart Clare A Paul Monk Cameron P Brown Andrew J Price 《The Knee》2018,25(2):286-295
Background
High tibial osteotomy (HTO) re-aligns the weight-bearing axis (WBA) of the lower limb. The surgery reduces medial load (reducing pain and slowing progression of cartilage damage) while avoiding overloading the lateral compartment. The optimal correction has not been established. This study investigated how different WBA re-alignments affected load distribution in the knee, to consider the optimal post-surgery re-alignment.Methods
We collected motion analysis and seven Tesla MRI data from three healthy subjects, and combined this data to create sets of subject-specific finite element models (total = 45 models). Each set of models simulated a range of potential post-HTO knee re-alignments. We shifted the WBA from its native alignment to between 40% and 80% medial–lateral tibial width (corresponding to 2.8°–3.1° varus and 8.5°–9.3° valgus), in three percent increments. We then compared stress/pressure distributions in the models.Results
Correcting the WBA to 50% tibial width (0° varus–valgus) approximately halved medial compartment stresses, with minimal changes to lateral stress levels, but provided little margin for error in undercorrection. Correcting the WBA to a more commonly-used 62%–65% tibial width (3.4°–4.6° valgus) further reduced medial stresses but introduced the danger of damaging lateral compartment tissues. To balance optimal loading environment with that of the historical risk of under-correction, we propose a new target: WBA correction to 55% tibial width (1.7°–1.9° valgus), which anatomically represented the apex of the lateral tibial spine.Conclusions
Finite element models can successfully simulate a variety of HTO re-alignments. Correcting the WBA to 55% tibial width (1.7°–1.9° valgus) optimally distributes medial and lateral stresses/pressures. 相似文献144.
Leanne MSG van Heur Leo HB Baur Marleen Tent Cara LB Lodewijks-van der Bolt Marjolijn Streppel Ron AG Winkens Henri EJH Stoffers 《BMC health services research》2010,10(1):37
Background
In our region (Eastern South Limburg, The Netherlands) an open access echocardiography service started in 2002. It was the first service of this kind in The Netherlands. Our study aims were: (1) to evaluate demand for the service, participation, indications, echocardiography outcomes, and management by the general practitioner (GP); (2) to analyse changes in indications and outcomes over the years. 相似文献145.
卵清白蛋白特异性T细胞克隆的建立及T细胞受体使用情况分析 总被引:2,自引:2,他引:2
目的:体外建立可长期培养的抗原特异性T细胞系及克隆,并分析其T细胞受体的使用情况。方法:用卵清白蛋白(OVA)免疫BALB/c小鼠,取淋巴结细胞在体外用抗原原复刺激建立抗原特异性T细胞系,通过能限稀释法进行克隆,应用锚定PCR方法分析其特异的T细胞受体的应用。结果:建立了H-2^d限制的OVA特异性T细胞系,获得了3株特异性较高的T细胞克隆,T细胞系中TCR AV11S4和BV4S1应用频率最高,3株T细胞克隆的TCR均为AV5S2和BV2S1,这些T细胞所使用的TCRα链和β链在CDR3区有明显的共性,结论:获得了卵清白蛋白特异的T细胞系和克隆,且其T细胞受体的应用有一定的限制性。 相似文献
146.
急性心肌梗死后的延迟冠状动脉内支架植入治疗 总被引:3,自引:0,他引:3
目的 评估急性心肌梗死后梗死相关冠状动脉内支架植入的临床疗效。方法 15 4例急性心肌梗死患者 ,平均年龄 (6 1± 12 )岁于发病后平均 13天行冠状动脉内支架术 ,所有患者常规服用肠溶阿司匹林和噻氯匹定。观察住院期和随访期的临床事件。结果 15 4例患者共植入 173个支架 (平均 1 1个 /例 )。支架植入的指征 :选择性初发病变 (denovo)占 2 4 3 % ,急性或濒危闭塞占13 9% ,有发生闭塞高危因素的病变占 6 1 8%。所用支架主要为Nir支架 (2 6 % )、Multi Link支架(19% )、XT支架 (13% )、Crossflex支架 (10 % ) ,等等。支架植入时最大球囊充盈压力为 (12± 2 )大气压。平均残余狭窄 (7± 8) %。住院期间无一例死亡、心肌梗死和需重复再通治疗 ,但术后“微坏死(micronecrosis)”率为 1 3%。术后 6个月病死率为 3 9% ,Q波型或非Q波型心肌梗死率为 1 9% ,支架内再狭窄而行再次冠状动脉腔内成形术率 6 1%。总的无心脏事件存活率为 89 6 %。结论 心肌梗死后行冠状动脉内支架术是安全的 ,并能改善患者的近期预后 ,但其远期疗效尚需进一步研究。 相似文献
147.
正全球范围内抗菌耐药性发生率正逐步上升。人们担心,欧洲移民人数的增加会加剧抗菌耐药性的形势。但是,目前尚无全面性的研究来评估移民对欧洲抗菌耐药性发生率带来的影响。2018年7月的《The Lancet. Infectious diseases》刊载了一项研究,研究者们开展了一项系统性的综述和元分析,识别并汇总了欧洲移民中抗菌耐药性的携带和感染数据,以探索不同移民群体间以及不同环境中抗菌耐药性的模式差异。为开展该系统性综述和元分析,研究者们搜索了MEDLINE、Embase、PubMed和Scopus数据库,不设语言限制,设定时间为2000年1月1日至 相似文献
148.
The purpose of the present article was to compare the results of primary total hip arthroplasty (THA) done because of developmental dysplasia of the hip (DDH) with the results of THA done because of idiopathic coxarthrosis (osteoarthritis) using data from the nationwide Norwegian Arthroplasty Register (NAR). In the period from 1987 to 2003, 84871 primary THAs were reported to the NAR. Of these, 6347 (7.5%) were performed because of sequelae after DDH, 788 (0.9%) because of sequelae after DDH with complete dislocation of the femoral head, and 59774 (71.0%) because of idiopathic coxarthrosis. The results of THAs after DDH were the same as those of THAs after idiopathic coxarthrosis after adjustments for younger age and for the use of more uncemented prostheses in patients with DDH. 相似文献
149.
L Aires LB Andersen D Mendonça C Martins G Silva J Mota 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(1):140-144
Aim: To analyse whether changes in physical activity index (PAI), screen time (ST: television, computer) and body mass index (BMI) made a contribution to longitudinal changes in fitness of children and adolescents. Additionally, we analysed the interaction between baseline fitness level and changes in fitness.
Methods: This is a 3-year longitudinal study of 345 high school students aged 11–19 years. Students performed curl-ups, push-ups and 20-m shuttle run tests from Fitnessgram. PA and ST were evaluated using a standard questionnaire. Standardized scores of fitness tests were summed. Changes over time were calculated as Δ1 (2007 minus 2006), Δ2 (2008 minus 2007) and Δ3 (2008 minus 2006).
Results: Changes in PAI were positively and independently associated with changes in fitness in Δ1 , Δ2 and Δ3 . Changes in BMI were negatively associated with changes in fitness in Δ3 . Participants highly fit at baseline were those who showed positive changes in PAI over Δ3 , decreased changes in ST and had the lowest increase in BMI over 3 years compared with those low-fit at baseline.
Conclusions: Changes in BMI were associated with changes in fitness over 3 years. However, changes in PAI were the best predictor for changes in fitness in each year and over the 3 years of evaluation in youth. 相似文献
Methods: This is a 3-year longitudinal study of 345 high school students aged 11–19 years. Students performed curl-ups, push-ups and 20-m shuttle run tests from Fitnessgram. PA and ST were evaluated using a standard questionnaire. Standardized scores of fitness tests were summed. Changes over time were calculated as Δ
Results: Changes in PAI were positively and independently associated with changes in fitness in Δ
Conclusions: Changes in BMI were associated with changes in fitness over 3 years. However, changes in PAI were the best predictor for changes in fitness in each year and over the 3 years of evaluation in youth. 相似文献
150.
AO Laiyemo G Murphy LB Sansbury Z Wang PS Albert PM Marcus RE Schoen AJ Cross A Schatzkin E Lanza 《Clinical gastroenterology and hepatology》2009,7(2):192-197
BACKGROUND AND AIMS: Recent studies have suggested that some hyperplastic polyps may be associated with an increased risk of colorectal cancer. Prospective information on the risk of adenoma recurrence associated with hyperplastic polyps is limited. We sought to investigate whether the coexistence of hyperplastic polyps with adenomas increases the risk of adenoma recurrence. METHODS: We used unconditional logistic regression models to examine the association between baseline hyperplastic polyps and subsequent adenoma recurrence during a 3-year follow-up evaluation, among 1637 participants in the Polyp Prevention Trial. RESULTS: A total of 437 participants (26.7%) had hyperplastic polyps coexisting with adenomas at baseline. Of these, 132 (30.2%) had at least one hyperplastic polyp in the proximal colon, whereas 305 (69.8%) had only distal hyperplastic polyps. When compared with subjects without any hyperplastic polyps at baseline, there was no statistically significant association between the presence of baseline hyperplastic polyps and recurrence of any adenoma (odds ratio [OR], 1.19; 95% confidence interval [CI], 0.94-1.51) or advanced adenoma (OR, 1.25; 95% CI, 0.78-2.03). Also, there was no association between hyperplastic polyp location and adenoma recurrence (OR, 1.01; 95% CI, 0.69-1.48) for any proximal hyperplastic polyp (OR, 1.26; 95% CI, 0.96-1.65) and for distal hyperplastic polyps. CONCLUSIONS: The coexistence of hyperplastic polyps with adenomas, irrespective of location, does not confer an increased risk of adenoma recurrence beyond that of adenomas alone within 3 years of follow-up evaluation. Prospective long-term studies on adenoma recurrence risk associated with hyperplastic polyps in screening populations are needed. 相似文献