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《Gait & posture》2016
BackgroundExercises replicating functional activities are commonly used in aquatic rehabilitation although it is not clear how the movement characteristics differ between the two environments. A systematic review was completed in order to compare the biomechanics of gait, closed kinetic chain and plyometric exercise when performed in water and on land.MethodsDatabases including MEDLINE, CINAHL, SPORTDiscus, Embase and the Cochrane library were searched. Studies were included where a functional lower limb activity was performed in water and on land with the same instructions. Standardized mean differences (SMD) and 95% confidence intervals were calculated for spatiotemporal, kinematic, force and muscle activation outcomes.Findings28 studies included walking or running (19 studies), stationary running (three), closed kinetic chain exercise (two), plyometric exercise (three) and timed-up and go (one). Very large effect sizes showed self-selected speed of walking (SMD >4.66) and vertical ground reaction forces (VGRF) (SMD >1.91) in water were less than on land, however, lower limb range of movement and muscle activity were similar. VGRF in plyometric exercise was lower in water when landing but more similar between the two environments in propulsion. Maximal speed of movement for walking and stationary running was lower in water compared to on land (SMD > 3.05), however was similar in propulsion in plyometric exercise.InterpretationDrag forces may contribute to lower self-selected speed of walking. Monitoring speed of movement in water assists in determining the potential advantages or limitations of aquatic exercise and the task specificity to land-based function. 相似文献
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The new EU Tobacco Product Directive (TPD) prohibits tobacco products containing additives that are toxic in unburnt form or that increase overall toxicity of the product. This paper proposes a strategy to assess additive attributed toxicity in the context of the TPD. Literature was searched on toxicity testing strategies for regulatory purposes from tobacco industry and governmental institutes. Although mainly traditional in vivo testing strategies have been applied to assess toxicity of unburnt additives and increases in overall toxicity of tobacco products due to additives, in vitro tests combined with toxicogenomics and validated using biomarkers of exposure and disease are most promising in this respect. As such, tests are needed that are sensitive enough to assess additive attributed toxicity above the overall toxicity of tobacco products, which can associate assay outcomes to human risk and exposure. In conclusion, new, sensitive in vitro assays are needed to conclude whether comparable testing allows for assessment of small changes in overall toxicity attributed to additives. A more pragmatic approach for implementation on a short-term is mandated lowering of toxic emission components. Combined with risk assessment, this approach allows assessment of effectiveness of harm reduction strategies, including banning or reducing of additives. 相似文献
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目的 研究3-乙酰基-11-羰基-β-乳香酸(AKBA)在大鼠体内的代谢途径.方法 大鼠ig AKBA 60 mg/kg后,收集胆汁、尿液及粪便,应用高效液相色谱-四级杆-离子阱质谱(HPLC-QTRAP-MS)技术分析AKBA在大鼠体内的代谢途径.结果 共检测到除原形药物外的15个代谢产物,提示AKBA在大鼠体内的主要代谢途径为去乙酰化、单羟基化、脱氢化及葡萄糖醛酸结合物.结论 AKBA在大鼠体内经历了广泛的Ⅰ相、Ⅱ相代谢,产生的代谢产物主要通过粪便及胆汁排泄;利用QTRAP技术的自动切换扫描(IDA)软件及增强型产物离子(EPI)扫描功能,能够快速得到高质量的MS2谱图,为AKBA代谢产物的鉴定提供了有效的检测手段. 相似文献
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《JACC: Cardiovascular Interventions》2014,7(9):1060-1069
ObjectivesThe aim of this study was to define age-stratified, procedure-specific benchmark radiation dose levels during interventional catheterization for congenital heart disease.BackgroundThere is a paucity of published literature with regard to radiation dose levels during catheterization for congenital heart disease. Obtaining benchmark radiation data is essential for assessing the impact of quality improvement initiatives for radiation safety.MethodsData were obtained retrospectively from 7 laboratories participating in the Congenital Cardiac Catheterization Project on Outcomes collaborative. Total air kerma, dose area product, and total fluoroscopy time were obtained for the following procedures: 1) patent ductus arteriosus closure; 2) atrial septal defect closure; 3) pulmonary valvuloplasty; 4) aortic valvuloplasty; 5) treatment of coarctation of aorta; and 6) transcatheter pulmonary valve placement.ResultsBetween January 2009 and July 2013, 2,713 cases were identified. Radiation dose benchmarks are presented including median, 75th percentile, and 95th percentile. Radiation doses varied widely between age groups and procedure types. Radiation exposure was lowest in patent ductus arteriosus closure and highest in transcatheter pulmonary valve placement. Total fluoroscopy time was a poor marker of radiation exposure and did not correlate well with total air kerma and dose area product.ConclusionsThis study presents age-stratified radiation dose values for 6 common congenital heart interventional catheterization procedures. Fluoroscopy time alone is not an adequate measure for monitoring radiation exposure. These values will be used as baseline for measuring the effectiveness of future quality improvement activities by the Congenital Cardiac Catheterization Project on Outcomes collaborative. 相似文献
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Marta J. Fiołka Krzysztof Grzywnowicz Ewaryst Mendyk Mirosław Zagaja Rafał Szewczyk Michał Rawski Radosław Keller Jolanta Rzymowska Jerzy Wydrych 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(12):1069-1080
In this paper, an antimycobacterial component of extracellular metabolites of a gut bacterium Raoultella ornithinolytica from D. veneta earthworms was isolated and its antimycobacterial action was tested using Mycobacterium smegmatis. After incubation with the complex obtained, formation of pores and furrows in cell walls was observed using microscopic techniques. The cells lost their shape, stuck together and formed clusters. Surface‐enhanced Raman spectroscopy analysis showed that, after incubation, the complex was attached to the cell walls of the Mycobacterium. Analyses of the component performed with Fourier transform infrared spectroscopy demonstrated high similarity to a bacteriocin nisin, but energy dispersive X‐ray spectroscopy analysis revealed differences in the elemental composition of this antimicrobial peptide. The component with antimycobacterial activity was identified using mass spectrometry techniques as a glycolipid–peptide complex. As it exhibits no cytotoxicity on normal human fibroblasts, the glycolipid–peptide complex appears to be a promising compound for investigations of its activity against pathogenic mycobacteria. 相似文献
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目的 研究海绵共附生链霉菌Streptomyces parvulus 162432的化学成分。方法 采用十八烷基硅烷键合硅胶填料(ODS)中压柱色谱和半制备高效液相色谱等技术进行分离纯化,得到的单体化合物采用HR-ESI-MS、NMR以及文献比对等方法进行鉴定,新化合物的绝对构型通过计算NMR和圆二色谱(ECD)确定。结果 从菌株Streptomyces parvulus 162432中分离纯化了9个环二肽类化合物,包括1个新化合物链霉菌二肽A(1)和8个已知化合物:环-(D-顺式-羟脯氨酸-L-苯丙氨酸)(2)、环-(D-脯氨酸-D-苯丙氨酸)(3)、环-(L-羟脯氨酸-L-亮氨酸)(4)、环-(L-羟脯氨酸-D-亮氨酸)(5)、环-(D-脯氨酸- L-亮氨酸)(6)、环-(L-脯氨酸-D-亮氨酸)(7)、环-(D-脯氨酸-L-异亮氨酸)(8)、环-(L-亮氨酸-D-缬氨酸)(9)。对分离得到的化合物1~9进行肿瘤细胞增殖细胞毒和抗菌活性评价,活性结果显示,化合物1~9在10 μg/mL下对肿瘤细胞增殖均未显示出明显的细胞毒活性;化合物9对苏云金芽孢杆菌显示抑菌活性,最小抑菌浓度(minimum inhibitory concentration,MIC)为25 μg/mL。结论 化合物1为新化合物,化合物2和4~9为首次从链霉菌Streptomyces parvulus中分离得到,化合物9具有一定的抗菌活性。 相似文献
69.
乙酰胆碱酯酶抑制剂是阿尔茨海默病治疗药物的研究热点。根据类胆碱学说,乙酰胆碱酯酶抑制剂可提高脑部神经递质乙酰胆碱的水平从而改善阿尔茨海默病患者的胆碱功能,并缓解神经性紊乱的症状。植物天然产物是乙酰胆碱酯酶抑制剂先导化合物的重要来源,其中生物碱为此类天然产物的重要组成部分。综述植物来源且具有抗乙酰胆碱酯酶活性生物碱的结构类型、作用机制及其构效关系。 相似文献
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