静态超声弹性成像：主观还是客观？定性还是定量？

静态超声弹性成像（Ultrasound Elastography）利用超声探测技术,检查组织的弹性特征,从一定程度上量化反映了医生在触诊中的主观感受,在科学研究和临床实践中有广泛的应用价值。本文综述了该项技术的研究背景、研究进展,并对其临床中遇到的问题做了初步的分析和探讨。以期通过今后的研究,帮助医生更好地获得弹性图像（Elastogram）,继而做出客观诊断。     

极速成像技术对原发性高血压患者颈动脉弹性的早期变化研究

目的:研究极速成像技术在原发性高血压患者颈动脉弹性的早期变化中的应用价值,为后续临床应用奠定基础。方法:选取本院2018年2月~2019年2月收治的原发性高血压患者216例,正常参加体检的人员215例作为对照组。两组均使用二维超声测量颈动脉内膜中层厚度(IMT)并计算出动脉僵硬度指数β。使用极速超声成像检测收缩早期脉搏波速度(BS)以及收缩末期脉搏波速度(ES),比较两组结果差异。结果:研究组BS、ES、动脉僵硬度指数与对照组差异均有统计学意义(P<0.05);而且BS、ES与动脉僵硬度指数β呈显著正相关。结论:极速成像技术测量的PWV对于早期原发性高血压患者颈动脉弹性的变化及发展可准确评估。     

Decrease in stiffness during shortening in calcium activated skinned muscle fibers

Single fibers from frog sartorius or semitendinosus muscle were mechanically skinned and activated in ATP salt solution containing 10 M Ca²⁺ (7°C). After development of an isometric contraction, fibers were released at constant speed (0.03–2.4s^–1). During ramp shortening, stiffness was determined from the slope of the tension-length diagram obtained during superimposed quick stretches. Both force and stiffness decreased, as the ramp shortening proceeded and approached a steady value after about 60 ms. An increase in speed of shortening caused a decrease in fiber tension and stiffness and an increase in the ratio of stiffness to tension, suggesting a decrease in both the number of attached crossbridges and in the average force per crossbridge.This work was supported by the Alexander von Humboldt-Stiftung and the Deutsche Forschungsgemeinschaft (RU 154/13)     

Health Care Expenditure and Income: A Global Perspective

This paper investigates the long‐run economic relationship between healthcare expenditure and income in the world using data on 167 countries over the period 1995–2012, collected from the World Bank data set. The analysis is carried using panel data methods that allow one to account for unobserved heterogeneity, temporal persistence, and cross‐section dependence in the form of either a common factor model or a spatial process. We estimate a global measure of income elasticity using all countries in the sample, and for sub‐groups of countries, depending on their geo‐political area and income. Our findings suggest that at the global level, health care is a necessity rather than a luxury. However, results vary greatly depending on the sub‐sample analysed. Our findings seem to suggest that size of income elasticity depends on the position of different countries in the global income distribution, with poorer countries showing higher elasticity. Copyright © 2016 John Wiley & Sons, Ltd.     

超声弹性成像在甲状腺良性结节射频消融中的应用价值及相关动态分析

甲状腺结节是临床上常见的疾病,近年来,随着甲状腺结节经皮微波或射频消融治疗的创新研究与发展应用,消融治疗在临床上取得了肯定的效果[1-2].对于消融后疗效的影像评价,已有学者利用弹性超声探讨研究[3],但一般是进行消融前与消融后即刻的对比,鲜有关于后续随访的报道.本研究拟分析运用弹性成像评价经皮射频消融治疗人体甲状腺良性结节的可行性及动态随访治疗后病灶质地的变化情况,总结实际操作经验,为甲状腺射频消融的长期疗效的评估提供新的客观影像依据.     

复方鳖甲软肝片辅助治疗慢性丙型肝炎纤维化疗效观察

目的 观察复方鳖甲软肝片辅助治疗慢性丙型肝炎纤维化的疗效.方法 将56例慢性丙肝患者随机分为观察组与对照组各28例,观察组采用复方鳖甲软肝片联合聚乙二醇干扰素 ɑ-2b(PegIFNɑ-2b)及利巴韦林治疗,对照组采用PegIFNɑ-2b及利巴韦林进行治疗,疗程24周,持续2个疗程.观察比较2组患者的病毒学应答、肝脏瞬时弹性成像,检查测定肝脏硬度值(LSM)、治疗前后血清丙氨酸氨基转氨酶(ALT)及透明质酸(HA)、层粘连蛋白(LN)、Ⅲ型前胶原(PC-Ⅲ)、Ⅳ型胶原(Ⅳ-C)、血清肿瘤坏死因子α(TNF-α)、转化生长因子-β1(TGF-β1)、白介素6(IL-6)的变化.结果 观察组患者获得持续病毒应答(SVR)20例,对照组18例,组间比较差异无统计学意义(P>0.05);两组LSM较治疗前均降低,观察组LSM显著低于对照组(P<0.05);治疗后观察组ALT、HA、LN、PC-Ⅲ、Ⅳ-C、TNF-α、TGF-β1、IL-6较治疗前显著降低,差异有统计学意义(P<0.05),观察组治疗效果优于对照组,差异有统计学意义(P<0.05).结论 复方鳖甲软肝片可显著改善慢性丙型肝炎肝纤维化程度,起到辅助治疗的作用.     

超声检查新技术在乳腺肿瘤诊断中的应用

高频彩色多普勒超声检查作为一种无创、方便快捷的影像学手段,已广泛应用于乳腺疾病的检查.近年来出现的超微血管成像、超声造影、弹性成像及三维全容积成像等新技术应用于临床诊断,提高了超声检查对乳腺良恶性肿瘤诊断的准确率、特异性及敏感性,并获得临床的认可,在乳腺疾病诊疗中发挥了更加重要的作用.     

声脉冲辐射力成像对乳腺肿瘤的诊断价值

目的：评价声脉冲辐射力成像（ARFI）技术对乳腺良恶性病变的鉴别诊断价值。方法选取84例患者共87个肿块进行常规超声、声触诊组织成像（VTI）及声触诊组织量化（VTQ）检查,得出剪切波速度值,并运用image J软件对VTI图像进行后处理得出肿块的平均光密度值,以病理结果为金标准,绘制受试者工作特征（ROC）曲线,评价ARFI的意义。结果经手术病理证实,87个乳腺肿块中良性病灶56个、恶性病灶31个。恶性病灶V T Q≥3．49 m／s （临界值）的病灶数为21个,＜3．49 m／s为10个。良性病灶V T Q≥3．49 m／s病灶数为3个,＜3．49 m／s为53个。恶性病灶平均光密度值大于或等于202．25（临界值）的病灶数为28个,＜202．25为3个。良性病变平均光密度值大于或等于202．25的病灶数6个,＜202．25为50个。乳腺良恶性病灶VTQ剪切波速度及VTI平均光密度值比较,差异均有统计学意义（P＝0．000）。关于乳腺肿瘤的诊断灵敏度、特异度、阳性预测值、阴性预测值、准确率及约登指数,常规超声分别为96．8％、67．8％、62．5％、97．4％、78．2％、0．645;ARFI分别为93．5％、98．2％、96．7％、96．5％、96．6％、0．917。结论 ARFI成像对乳腺肿瘤诊断的特异度、准确率优于常规超声。     

The Demand for Cigarettes as Derived from the Demand for Weight Loss: A Theoretical and Empirical Investigation

This paper offers an economic model of smoking and body weight and provides new empirical evidence on the extent to which the demand for cigarettes is derived from the demand for weight loss. In the model, smoking causes weight loss in addition to having direct utility benefits and direct health consequences. It predicts that some individuals smoke for weight loss and that the practice is more common among those who consider themselves overweight and those who experience greater disutility from excess weight. We test these hypotheses using nationally representative data in which adolescents are directly asked whether they smoke to control their weight. We find that, among teenagers who smoke frequently, 46% of girls and 30% of boys are smoking in part to control their weight. As predicted by the model, this practice is significantly more common among those who describe themselves as too fat and among groups that tend to experience greater disutility from obesity. We conclude by discussing the implications of these findings for tax policy; specifically, the demand for cigarettes is less price elastic among those who smoke for weight loss, all else being equal. Public health efforts to reduce smoking initiation and encourage cessation may wish to design campaigns to alter the derived nature of cigarette demand, especially among adolescent girls. Copyright © 2014 John Wiley & Sons, Ltd.