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111.
Background: Body mass index (BMI) is often criticised since it doesn’t consider sex, age and ethnicity, which may affect the height scaling exponent of the equation.Aims: First, to identify specific height scaling exponents (α) based on sex, age and ethnicity. Second, to assess the performance of the current vs the proposed BMI equations (1) to predict total fat mass (TFM) and metabolic syndrome (MetS) severity and (2) to correctly identify obese individuals and those having MetS.Methods: In total, 41,403 individuals aged 20–80?years (NHANES, 1999–2014) were studied. Specific “α” were identified using the Benn formula. Various statistical approaches were performed to assess performances of the current vs the proposed-BMIs.Results: The proposed “α” varies from 1.2 to 2.5, after considering sex, age and ethnicity. BMIs calculated using the proposed “α” showed a similar capacity to predict TFM and MetS severity and to correctly identify obese individuals and those having MetS compared to the current BMI.Conclusions: Despite sex, age and ethnicity modulating the height scaling exponent of the BMI equation, using these proposed exponents in the BMI equation didn’t improve the capacity to predict TFM and MetS severity, suggesting that the current BMI remains a valid clinical tool. 相似文献
112.
目的分析乳腺癌动态对比增强磁共振成像(dynamic contrast-enhanced magnetic resonance imaging,DCE-MRI)参数、表观扩散系数(apparent diffusion coefficient,ADC)与病理分子预后标记物的相关性。材料与方法回顾性分析我院106例乳腺癌患者临床资料,分别比较雌激素受体(estrogen receptor,ER)、孕激素受体(progesterone receptor,PR)、细胞增殖抗原Ki67及雄激素受体(androgen receptor,AR)阳性表达与阴性表达者DCE-MRI参数、ADC差异,并分析DCE-MRI参数、ADC与ER、PR、Ki67、AR表达的相关性。结果经Spearman秩相关检验,发现ER、PR及AR阳性表达与直径、边缘毛刺呈显著负相关(P<0.05),AR表达阳性表达还与达峰时间(time to peak,TTP)、ADC值呈显著正相关(P<0.05);Ki67阳性表达与直径、边缘毛刺呈显著正相关(P<0.05),与TTP、ADC值呈显著负相关(P<0.05)。结论DCE-MRI形态学参数及TTP、ADC值与乳腺癌分子生物学标记物具有一定相关性,对判断乳腺癌预后有利。 相似文献
113.
《Dental materials》2020,36(1):60-67
ObjectivesThe rapidly increasing use of zirconia-based CAD/CAM multi-layer structures in dentistry calls for a thorough evaluation of their mechanical integrity. This work examines the effect of the multi-layering architecture as well as variations in composition and inclusion of pigments among the layers on the flexural strength of multi-layer zirconias.MethodsA modified 4-point bending test, aided by a Finite Element Analysis (FEA), was used to probe the interfacial strength of 3 classes of yttria-partially-stabilized zirconia: Ultra Translucent Multi-Layer (UTML—5Y-PSZ), Super Translucent Multi-Layer (STML—4Y-PSZ), Multi-Layer (ML—3Y-PSZ). In accord with the size limitation (22-mm height) of CAD/CAM pucks, test samples were prepared in the form of “long” (25 × 2 × 3 mm) and “short” (17.8 × 1.5 × 2 mm) beams. Homogeneous beams (both long and short) were produced from either the Enamel (the lightest shade) or Dentin (the darkest shade) layer, whereas multi-layer beams (short beam only) were obtained by cutting the pucks along their thickness direction, where the material components of various shades were stacked.ResultsThe Enamel and Dentin layers exhibited similar flexural strength for a given material class, with ML amassing the highest strength (800–900 MPa) followed by STML (560–650 MPa) and UTML (470–500 MPa). The 3 classes of multi-layer zirconia showed a trade-off between strength and translucency, reflecting different yttria contents in these materials. The failure stress of the cross-sectional multi-layer beams was, however, ∼30% lower than that of their Enamel or Dentin layer counterparts, regardless of material tested.SignificanceThe weakness of interfaces is a drawback in these materials. Additionally, when measuring strength using short beam flexure, friction between the specimen and supporting pins and accuracy in determining loading span distances may lead to major errors. 相似文献
114.
采用HPLC法测定了25℃、100 r/min条件下平衡48 h时氟非尼酮在水性溶剂和非水溶剂中的溶解度。结果表明,氟非尼酮在水及其他水性溶剂中微溶,溶解度约为2.5 mg/ml,溶剂的pH值对溶解度影响小;氟非尼酮易溶于乙醇,可溶于聚乙二醇400、1,2-丙二醇和异丙醇,微溶于甘油。摇瓶法测得氟非尼酮的油水分配系数(logP)值为1.182,略有亲脂性。以乳猪皮肤为模型,采用改良的Franz扩散池法评价不同载药量(0.5%和1%)凝胶及溶液的经皮渗透特性。结果表明,2种载药量的氟非尼酮凝胶的经皮渗透行为均符合零级模型,1%凝胶的24 h单位面积累积渗透量(Q24h)和单位面积皮肤滞留量(Qskin)均比0.5%凝胶增加约1倍;同时,0.5%溶液的Q24h和Qskin结果介于2种载药量凝胶之间。 相似文献
115.
Hyungjin Kim Jeong Min Lee Jeong Hee Yoon Jin-Young Jang Sun-Whe Kim Ji Kon Ryu Stephan Kannengiesser Joon Koo Han Byung Ihn Choi 《Korean journal of radiology》2015,16(6):1216-1225
ObjectiveTo investigate the image quality (IQ) and apparent diffusion coefficient (ADC) of reduced field-of-view (FOV) di-ffusion-weighted imaging (DWI) of pancreas in comparison with full FOV DWI.ResultsOn qualitative analysis, reduced FOV DWI showed better anatomic structure visualization (2.76 ± 0.79 at b = 0 s/mm2 and 2.81 ± 0.64 at b = 400 s/mm2), lesion conspicuity (3.11 ± 0.99 at b = 0 s/mm2 and 3.15 ± 0.79 at b = 400 s/mm2), IQ score (8.51 ± 2.05 at b = 0 s/mm2 and 8.79 ± 1.60 at b = 400 s/mm2), and higher clinical utility (3.41 ± 0.64), as compared to full FOV DWI (anatomic structure, 2.18 ± 0.59 at b = 0 s/mm2 and 2.56 ± 0.47 at b = 500 s/mm2; lesion conspicuity, 2.55 ± 1.07 at b = 0 s/mm2 and 2.89 ± 0.86 at b = 500 s/mm2; IQ score, 7.13 ± 1.83 at b = 0 s/mm2 and 8.17 ± 1.31 at b = 500 s/mm2; clinical utility, 3.14 ± 0.70) (p < 0.05). Artifacts were significantly improved on reduced FOV DWI (2.65 ± 0.68) at b = 0 s/mm2 (full FOV DWI, 2.41 ± 0.63) (p < 0.001). On quantitative analysis, there were no significant differences between the 2 DWI sequences in ADCs of various pancreatic lesions and parenchyma (p > 0.05). ADCs of adenocarcinomas (1.061 × 10-3 mm2/s ± 0.133 at reduced FOV and 1.079 × 10-3 mm2/s ± 0.135 at full FOV) and neuroendocrine tumors (0.983 × 10-3 mm2/s ± 0.152 at reduced FOV and 1.004 × 10-3 mm2/s ± 0.153 at full FOV) were significantly lower than those of parenchyma (1.191 × 10-3 mm2/s ± 0.125 at reduced FOV and 1.218 × 10-3 mm2/s ± 0.103 at full FOV) (p < 0.05).ConclusionReduced FOV DWI of the pancreas provides better overall IQ including better anatomic detail, lesion conspicuity and subjective clinical utility. 相似文献
116.
目的 探讨磁共振表观弥散系数(ADC)变化率(即△ADC)在肝细胞肝癌(HCC)单次经导管肝动脉化疗栓塞术(TACE)术后疗效评价中的应用价值.方法 选择48例确诊为中晚期HCC并于TACE术前、术后1个月接受常规CT、MRI扫描以及MRI弥散加权成像和动态增强扫描的患者,建立所有患者的随访数据,随访中以肿瘤出现进展为随访结束点,记录患者治疗后肿瘤无进展生存期(PFS);以TACE术后1个月再次行数字减影血管造影(DSA)的肿瘤染色结果作为“金标准”,将病灶按治疗效果分为良好组、中等组及差组3组,并根据各组PFS绘制生存曲线.分别比较△ADC、CT及MRI 3种方法对TACE术后疗效的判定价值,并与“金标准”的一致性进行检验.结果 48例患者共56个病灶纳入分析,以“金标准”评价治疗效果,结果:良好组30个、中等组16个、差组10个,3组间生存曲线差异有统计学意义(x2=29.89,P<0.01),中位PFS分别为7.5、4.0和1.1个月;TACE术后各组ADC均升高,3组间△ADC差异有统计学意义(F=22.41,P<0.01),且3组间生存曲线差异亦有统计学意义(x2=26.57,P<0.01),中位PFS分别为7.5、4.6和1.8个月.经Kappa检验,△ADC与“金标准”疗效评价方法具有一致性(Kappa值为0.542,P<0.01);以MRI和CT评价治疗效果,其与“金标准”的一致性较差(Kappa值分别为0.328和0.260,P均<0.05),3组间生存曲线仅MRI评价方法显示差异有统计学意义(x2=30.623,P<0.01).结论 △ADC能及时、客观地评价TACE治疗效果,对指导患者术后的后续治疗有重要临床意义. 相似文献
117.
118.
119.
T. Sathyapalan M. Aye A.S. Rigby N.J. Thatcher S.R. Dargham E.S. Kilpatrick S.L. Atkin 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2018,28(7):691-697
Background
Hormone replacement therapy may be beneficial for cardiovascular disease risk (CVR) in post-menopausal women. Soy isoflavones may act as selective estrogen receptor modulators. The aim of this study was to evaluate whether soy isoflavones had an effect on CVR markers.Methods
The expected 10-year risk of cardiovascular disease and mortality were calculated as a secondary endpoint from a double blind randomised parallel study involving 200 women (mean age 55 years, Caucasian, Hull, UK, 2012) in the early menopause who were randomised to 15 g soy protein with 66 mg isoflavone (SPI) or 15 g soy protein alone (depleted of all isoflavones; SP) given as a snack bar between meals daily for 6 months. Age, diabetes, smoking, blood pressure and lipid profiles were used to calculate CVR using the Framingham CVR engine.Results
SPI treatment resulted in a significant reduction in the metabolic parameters and systolic blood pressure compared to SP (p < 0.01). There were no changes in fasting lipid profile and diastolic blood pressure with either treatment. At 6 months, changes in these parameters with SPI treatment were reflected in a calculated 27% (p < 0.01) reduction in 10 year coronary heart disease risk, a 37% (p < 0.01) reduction in myocardial infarction risk, a 24% (p < 0.04) reduction in cardiovascular disease and 42% (p < 0.02) reduction in cardiovascular disease death risk.Conclusions
Supplementation with soy protein with isoflavones for 6 months significantly improved CVR markers and calculated CVR at 6 months during early menopause compared to soy protein without isoflavones.ISRCTN registry
ISRCTN34051237. 相似文献120.
Hideyuki Kawashima Patrick W. Serruys Rodrigo Modolo Michele Pighi Rutao Wang Masafumi Ono Jean-Paul Aben Chun Chin Chang Hadewych Van Hauwermeiren Bill Brunnett Martijn Cox Liesbeth Rosseel Darren Mylotte Philippe Pibarot Willem J. Flameng Yoshinobu Onuma Osama Soliman 《JACC: Cardiovascular Interventions》2021,14(14):1523-1534
ObjectivesThis study aimed to validate a dedicated software for quantitative videodensitometric angiographic assessment of mitral regurgitation (QMR).BackgroundQuantitative videodensitometric aortography of aortic regurgitation using the time-density principle is a well-documented technique, but the angiographic assessment of mitral regurgitation (MR) remains at best semi-quantitative and operator dependent.MethodsFourteen sheep underwent surgical mitral valve replacement using 2 different prostheses. Pre-sacrifice left ventriculograms were used to assess MR fraction (MRF) using QMR and MR volume (MRV). In an independent core lab, the CAAS QMR 0.1 was used for QMR analysis. In vitro MRF and MRV were assessed in a mock circulation at a comparable cardiac output to the in vivo one by thermodilution. The correlations and agreements of in vitro and in vivo MRF, MRV, and interobserver reproducibility for QMR analysis were assessed using the averaged cardiac cycles (CCs).ResultsIn vivo derived MRF by QMR strongly correlated with in vitro derived MRF, regardless of the number of the CCs analyzed (best correlation: 3 CCs y = 0.446 + 0.994x; R = 0.784; p =0.002). The mean absolute difference between in vitro derived MRF and in vivo derived MRF from 3 CCs was 0.01 ± 4.2% on Bland-Altman analysis. In vitro MRV and in vivo MRV from 3 CCs were very strongly correlated (y = 0.196 + 1.255x; R = 0.839; p < 0.001). The mean absolute difference between in vitro MRV and in vivo MRV from 3 CCs was –1.4 ± 1.9 ml. There were very strong correlations of in vivo MRF between 2 independent analysts, regardless of the number of the CCs.ConclusionsIn vivo MRF using the novel software is feasible, accurate, and highly reproducible. These promising results have led us to initiate the first human feasibility study comprising patients undergoing percutaneous mitral valve edge-to-edge repair. 相似文献