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52.
An extensive literature has established that it is common for respondents to ignore attributes of the alternatives within choice experiments. In most of the studies on attribute non‐attendance, it is assumed that respondents consciously (or unconsciously) ignore one or more attributes of the alternatives, regardless of their levels. In this paper, we present a new line of enquiry and approach for modelling non‐attendance in the context of investigating preferences for health service innovations. This approach recognises that non‐attendance may not just be associated with attributes but may also apply to the attribute's levels. Our results show that respondents process each level of an attribute differently: while attending to the attribute, they ignore a subset of the attribute's levels. In such cases, the usual approach of assuming that respondents either attend to the attribute or not, irrespective of its levels, is erroneous and could lead to misguided policy recommendations. Our results indicate that allowing for attribute‐level non‐attendance leads to substantial improvements in the model fit and has an impact on estimated marginal willingness to pay and choice predictions.Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
53.
ObjectivesThis study characterized the determinants of carotid intima-media thickness (cIMT) in a large (n > 4,000) longitudinal cohort of healthy young people age 9 to 21 years.BackgroundGreater cIMT is commonly used in the young as a marker of subclinical atherosclerosis, but its evolution at this age is still poorly understood.MethodsAssociations between cardiovascular risk factors and cIMT were investigated in both longitudinal (ages 9 to 17 years) and cross-sectional (ages 17 and 21 years) analyses, with the latter also related to other measures of carotid structure and stress. Additional use of ultra-high frequency ultrasound in the radial artery at age 21 years allowed investigation of the distinct layers (i.e., intima or media) that may underlie observed differences.ResultsFat-free mass (FFM) and systolic blood pressure were the only modifiable risk factors positively associated with cIMT (e.g., mean difference in cIMT per 1-SD increase in FFM at age 17: 0.007 mm: 95% confidence interval [CI]: 0.004 to 0.010; p < 0.001), whereas fat mass was negatively associated with cIMT (difference: ?0.0032; 95% CI: 0.004 to ?0.001; p = 0.001). Similar results were obtained when investigating cumulative exposure to these factors throughout adolescence. An increase in cIMT maintained circumferential wall stress in the face of increased mean arterial pressure when increases in body mass were attributable to increased FFM, but not fat mass. Risk factor?associated differences in the radial artery occurred in the media alone, and there was little evidence of a relationship between intimal thickness and any risk factor.ConclusionsSubtle changes in cIMT in the young may predominantly involve the media and represent physiological adaptations as opposed to subclinical atherosclerosis. Other vascular measures may be more appropriate for the identification of arterial disease before adulthood.  相似文献   
54.
Forensic Science South Australia (FSSA) has been using STRmix™ software to deconvolute all reported DNA mixtures since 2012. Almost a decade of deconvolutions had led to a substantial repository of analysed profile data that can be interrogated to observe trends in case type, location or occurrence. In addition, deconvolutions can be compared in order to identify common DNA donors and reveal new intelligence information in cases where DNA profiling has previously provided no investigative information. As a proof of concept all samples deconvoluted as part of criminal casework (suspect or no-suspect) were interrogated and compared to each other using the mixture-to-mixture comparison feature in STRmix™. Within the Adelaide region there were 32 groups of cases that had evidence samples linked by a common DNA donor with LR > 1 million which was in addition to direct links and mixture searching links identified previously. These groups of cases can then be interrogated to reveal additional information to inform Police intelligence gathering. Our paper reports on the findings of this proof-of-concept study.  相似文献   
55.
Simultaneous occurrence of cylindrospermopsin (CYN) and microcystin-LR (MCLR) has been reported in the aquatic environment and thus human exposure to such mixtures is possible. As data on the combined effects of CYN/MCLR are scarce, we aimed to investigate the adverse effects related to genotoxic activities induced by CYN (0.125, 0.25 and 0.5 µg/mL) and MCLR (1 µg/mL) as single compounds and their combinations in HepG2 cells after 24 and 72 h exposure. CYN and CYN/MCLR induced DNA double-strand breaks after 72 h exposure, while cell cycle analysis revealed that CYN and CYN/MCLR arrested HepG2 cells in G0/G1 phase. Moreover, CYN and the combination with MCLR upregulated CYP1A1 and target genes involved in DNA-damage response (CDKN1A, GADD45A). Altogether, the results showed that after 72 h exposure genotoxic activity of CYN/MCLR mixture was comparable to the one of pure CYN. On the contrary, MCLR (1 µg/mL) had no effect on the viability of cells and had no influence on cell division. It did not induce DNA damage and did not deregulate studied genes after prolonged exposure. The outcomes of the study confirm the importance of investigating the combined effects of several toxins as the effects can differ from those induced by single compounds.  相似文献   
56.
目的:观察消肿止痛合剂对大鼠随意皮瓣血管再生及血管内皮生长因子(VEGF)-Dll4/Notch信号通路的影响。方法:将240只健康SD大鼠随机分为6组,分别为空白组、假手术组、模型组、消肿止痛合剂组(消肿组)、消肿止痛合剂+Notch阻断剂MK-0752(MK)组(消肿+MK组)和消肿止痛合剂组+VEGF受体抑制剂axitinib(AXI)组(消肿+AXI组)。观察皮瓣毛细血管充盈时间;HE染色观察皮瓣组织新生毛细血管的数量、微血管密度、微血管管径及血管成活面积;ELISA法检测血清中VEGF的含量;RT-qPCR检测大鼠皮瓣组织中VEGFA、Notch和Dll4的mRNA表达水平。结果:与模型组相比,消肿组第10天毛细血管充盈时间降低(P<0.05);与消肿组相比,消肿+AXI组的毛细血管充盈时间增加(P<0.05)。模型组大鼠皮瓣组织细胞排列紊乱,细胞核稀疏,可见明显水肿和大量白细胞浸润;消肿组和消肿+MK组水肿明显减轻,组织间隙炎症细胞浸润减少,其中消肿+MK组减轻更为明显。与模型组相比,消肿组微血管数量、密度和面积均显著增加,VEGF的含量显著增加,VEGFA、Notch和Dll4的mRNA表达量显著升高(P<0.05);与消肿组相比,AXI干预后微血管数量、密度和面积均显著减少,VEGF的含量降低,VEGFA、Notch和Dll4的mRNA表达量降低(P<0.05);MK干预后,VEGFA的mRNA表达水平升高,而Notch和Dll4 mRNA表达增加的趋势被有效抑制(P<0.05)。结论:消肿止痛合剂能够促进皮瓣术后血管的再生,从而增强了随意型皮瓣的成活率,可能与影响VEGF-Dll4/Notch信号转导通路有关。  相似文献   
57.
Correction to: Cheng FS, Pan D, Chang B, Jiang M, Sang LX. Probiotic mixture VSL#3: An overview of basic and clinical studies in chronic diseases. World J Clin Cases 2020; 8: 1361-1384. We are the team of Min Jiang and Li-Xuan Sang from the First Affiliated Hospital, China Medical University. Now we solemnly declare that the studies mentioned in this article[1] evaluated the probiotic formulation known as VSL#3 before January 31, 2016. The probiotic formulation is now commonly referred to as De Simone Formulation. In addition, the product currently known as VSL#3 is not the same as De Simone Formulation. De Simone Formulation is now available as Visbiome in the United States and Vivomixx in Europe.  相似文献   
58.
目的 探讨夏枯草消瘤合剂对Lewis肺癌小鼠的治疗作用。方法 采用C57BL/6小鼠Lewis肺癌移植瘤模型,将30只小鼠随机分为3组:模型对照组、夏枯草消瘤合剂组(M组)、顺铂组(DDP组),连续用药14 d。通过对Lewis肺癌小鼠的大体观察,测定肿瘤大小,HE染色方法测定肿瘤病理组织学变化,免疫组化方法测定肿瘤组织的细胞周期蛋白D1(CyclinD1)和P16的表达情况。结果 模型对照组瘤体质量最重,与其他组比较差异均有统计学意义(P<0.05);M组可在一定程度上改善小鼠的生存状态及生活质量;各组小鼠的肿瘤生长曲线及HE染色结果显示:M组可抑制肿瘤细胞的生长,且对正常细胞有保护作用;M组、DDP组均可显著降低CyclinD1阳性表达(P<0.01),但是M组对于提高P16阳性表达的效果不显著。结论 夏枯草消瘤合剂具有较好的抑制肺癌生长的作用。  相似文献   
59.
目的建立心衰宁合剂的质量标准。方法采用薄层色谱法(TLC)对处方中的红参、黄芪、丹参进行定性鉴别;用高效液相色谱法(HPLC)测定心衰宁合剂中人参皂苷Rb1的含量。结果薄层图谱斑点清晰,阴性对照无干扰;人参皂苷Rb1在1.095~5.475 μg呈良好的线性关系,平均回收率为 97.3%,RSD为1.98%。结论建立的方法简便,准确,重复性好,精密度高,可用于心衰宁合剂的质量控制。  相似文献   
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