腹腔脏器病变术前经腹超声检查漏诊及误诊原因

目的　评估腹腔脏器病变患者术前经腹超声检查报告并分析超声漏诊及误诊的原因。方法　通过病理工作站导出2013年3月1日至8月31日因腹腔脏器（肝脏、胆囊、胆管、胰腺、脾脏、肾脏、肾上腺和阑尾）病变于北京协和医院进行手术治疗的住院患者病理资料，评估相应超声报告，记录漏、误诊报告信息，分析漏、误诊原因。结果　共评估超声报告1081份，漏、误诊报告58份（5.37%，58/1081），其中肝脏病变6例（5.77%，6/104），均为误诊；胆囊和胆管病变6例（1.30%，6/462），漏诊5例、误诊1例；胰腺病变14例（19.72%，14/71），均为漏诊；肾脏和肾上腺病变20例（6.47%，20/309），漏诊11例、误诊9例；阑尾病变12例（16.00%，12/75），漏诊11例、误诊1例。漏诊结节样病变最大径平均值显著低于误诊病变（P=0.001）。结论　不同腹腔脏器病变因性质、部位、体积以及超声本身的局限性等原因导致超声漏诊或误诊，超声医师在临床工作中应做到全面、仔细、谨慎，了解各腹腔脏器病变的自身特点以及超声显像的局限性，不断积累经验，尽可能避免不必要的错误。     

Syrah grape skin valorisation using ultrasound-assisted extraction: Phenolic compounds recovery,antioxidant capacity and phenolic profile

The influence of ultrasound power (1000–3000 W/L), citric acid concentration (0–3%) and solid:liquid ratio (1:5–1:15) on the phenolic compounds recovery and antioxidant capacity of Syrah grape skin extracts were evaluated. Total phenolic compounds varied from 6485 to 11732 mg gallic acid/100 g and monomeric anthocyanin content from 453 to 685 mg malvidin-3-glucoside/100 g. The antioxidant capacity measured by ORAC and ABTS methods ranged from 230 to 516 μmol Trolox/g and from 442 to 939 μmol Trolox/g, respectively. The most suitable conditions chosen for extraction, within the studied ranges, were 3000 W/L of power, 2.5% citric acid and solid:liquid ratio of 1:15. The extraction yield was satisfactory, with a recovery of 59% of the quantified phenolic compounds, with only 3 min of processing. Ultrasound was considered a suitable method as compared to the conventional extraction, improving the extraction of phenolic acids and facilitating their release.     

The influence of sonication time on the biogenic amines formation as a critical point in uncured dry-fermented beef manufacturing

In this study, the influence of sonication time on the biogenic amines formation as a critical point in uncured dry-fermented beef manufacturing was studied. Samples of musculus semimembranosus were sonicated at different times (5 and 10 min) using ultrasound cold bath (4 °C) in acid whey (US 40 kHz and acoustic power 480 W). The effect of sonication on biogenic amine (BA) formation was investigated during 93 days of ripening period. Other parameters (pH value, water activity, microbial counts) that might provide further information on the product under study were also determined. The use of ultrasound during beef marinating in acid whey has a positive effect on retarding histamine (HIS), cadaverine (CAD), tyramine (TYR) and putrescine (PUT) formation. Moreover, the sonication treatment did not inhibit the growth of lactic acid bacteria (LAB) in dry-fermented beef during the whole ripening period. The pathogen bacteria (Staphylococcus aureus, Clostridium sp., Listeria monocytogenes) were not detected in all samples neither after 31 nor after 93 days of ripening period.     

脑血流动力学及脑氧饱和度变化与感染性休克患者预后的相关性:前瞻性队列研究

目的探讨大脑中动脉血流动力学相关指标及脑氧饱和度变化与感染性休克患者预后的相关性。方法前瞻性收集2018年5月至2019年3月在中南大学湘雅医院重症医学科住院治疗的感染性休克患者临床资料,根据28 d内是否死亡,将患者分为死亡组和存活组。比较两组患者一般资料,入重症监护室即刻和初始复苏治疗6 h后动脉和中心静脉血气指标,重症心脏超声指标,器官功能指标,Sepsis生物标志物指标,液体复苏治疗6 h后大脑中动脉血流速度、灌注指数、动态脑血管自动调节功能[瞬时脑充血反应率(transient hyperemic response ratio,THRR)]以及脑氧饱和度变化。采用多因素Logistic回归,分析影响感染性休克患者预后的危险因素。结果 51例符合纳入和排除标准的感染休克患者入选本研究,男性31例,女性20例,年龄(53±13)岁,28 d死亡率为43%。死亡组的序贯性器官衰竭评分(sequential organ failure assessment,SOFA)(P=0. 007)、入室急性生理和慢性健康状况评估(acute physiology and chronic health evaluationⅡ,APACHEⅡ)评分(P=0. 026)以及高峰APACHEⅡ评分(P<0. 001)均高于存活组。初始复苏治疗6 h后,死亡组的氧合指数低于存活组(P=0. 047),而中心静脉-动脉二氧化碳分压差(central venous-to-arterial carbon dioxide difference,Pcva CO_2)则高于存活组(P=0. 044)。死亡组动态脑血管自动调节功能受损者(THRR<1. 09)多于存活组(P=0. 025),脑氧饱和度(regional cerebral oxygen saturation,rSO_2)均值低于存活组(P=0. 031)且rSO_2均值<60%者多于存活组(P=0. 010)。多因素Logistic回归分析显示,高峰APACHEⅡ评分(OR=1. 099,95%CI:1. 009～1. 196,P=0. 030)、液体复苏治疗6 h后的Pcv-aCO_2(OR=1. 320,95%CI:1. 001～1. 742,P=0. 050)、THRR<1. 09 (OR=4. 952,95%CI:1. 130～21. 70,P=0. 034)和rSO_2均值<60%(OR=4. 817,95%CI:1. 392～16. 663,P=0. 013)是预测感染性休克患者28 d内死亡的独立危险因素。结论感染性休克患者死亡率高,脑血流动力学和rSO_2指标中动态脑血管自动调节功能障碍(THRR<1. 09)与rSO_2均值<60%是28 d死亡率增加的独立预测因素。     

术前2h饮用碳水化合物对老年胃肠道手术患者胃容量及反流误吸风险的影响:前瞻性随机对照研究

目的应用床旁超声技术观察术前2 h饮用碳水化合物对老年胃肠道手术患者麻醉前胃容量的影响,并评估患者发生反流误吸的风险。方法前瞻性选取2017年12月至2018年10月,在四川省人民医院行胃肠道手术的老年患者(>65岁),随机分为试验组和对照组。试验组常规禁食8 h,术前2 h口服200 ml碳水化合物;对照组要求术前禁食8 h,禁饮4 h。麻醉前采用床旁超声技术测量45°半坐位及右侧卧位胃窦部头尾径及前后径,分别计算两种体位下的胃窦部横截面积(cross-sectional area,CSA)、胃容量(gastric volume,GV)及胃容量与体重比(GV/weight,GV/W)。采用GV超声半定量3分评估法及GV/W分级法评估患者发生反流误吸的风险。结果共纳入69例符合入选和排除标准的患者,其中试验组33例,对照组36例。两组基线资料、手术类别及美国麻醉医师学会分级无统计学差异(P均>0. 05)。半坐位下,试验组和对照组的GV/W分别为(0. 57±0. 23) ml/kg和(0. 44±0. 21) ml/kg;右侧卧位下,试验组和对照组的CSA分别为(578. 8±71. 5) mm2和(513. 3±53. 2) mm2,GV分别为(21. 2±11. 1) ml和(12. 9±6. 8) ml,GV/W分别为(0. 36±0. 17) ml/kg和(0. 20±0. 11) ml/kg,上述指标两组间均存在统计学差异(P均<0. 05)。GV超声半定量评分:试验组0分17例(51. 5%,17/33),1分15例(45. 5%,15/33),2分1例(3. 0%,1/33),对照组0分25例(69. 4%,25/36),1分11例(30. 6%,11/36),2分0例(0,0/33),两组评分构成比无统计学差异(P>0. 05)。反流误吸风险评估:试验组极低风险者占比81. 8%(27/33)、低风险18. 2%(6/33)、高风险0 (0/33),对照组极低风险者占比94. 4%(34/36)、低风险5. 6%(2/36)、高风险0 (0/33),两组间构成比亦无统计学差异(P>0. 05)。结论老年胃肠道手术患者术前2 h饮用200 ml碳水化合物虽可以增加麻醉前胃容量,但并不增加反流误吸的风险。     

肾脏叶间动脉阻力指数对Ⅰ型心肾综合征的诊断价值

目的探讨彩色多普勒超声测量肾脏叶间动脉阻力指数(resistance index,RI)对Ⅰ型心肾综合征(cardiorenal syndrome,CRS)的诊断价值。方法选取2017年6月1日至2018年3月1日收住民航总医院急诊综合病房并诊断为Ⅰ型CRS的20例患者作为试验组(CRS组),选取同期诊断为单纯急性心力衰竭的患者20例作为对照组,分析两组患者的临床特征、实验室检查及用药情况,并根据受试者工作特征(receiver operating characteristic,ROC)曲线评价肾动脉RI对Ⅰ型CRS的诊断价值。结果两组患者年龄、左心室射血分数、心功能分级、心率及脉压差差异无统计学意义(P均>0. 05),CRS组患者的氨基末端脑钠尿肽、肌酐水平、呋塞米剂量以及肾动脉RI均高于对照组,而肾小球滤过率低于对照组,差异具有统计学意义(P均<0. 05)。ROC曲线下面积为0. 78,取最佳截点值0. 70时预测Ⅰ型CRS的敏感度为80%,特异度为80%。结论作为一种新的手段,肾动脉RI可与传统方法相互补充,对诊断Ⅰ型心肾综合征患者具有潜在应用价值。     

镍基MOF电极材料物理超声改性及电化学性能

采用水热法合成了以4,4′-联苯二甲酸(BPDC)为配体的Ni-金属有机框架(MOF),利用低成本、无污染的物理超声法在不改变Ni-MOF晶体结构的前提下对其进行改性,使块状Ni-MOF表面产生孔隙,改善Ni-MOF表面微/纳米结构,提高其电化学性能。通过扫描电子显微镜(SEM)图、X射线衍射(XRD)谱、循环伏安(CV)曲线和恒电流充放电(GCD)曲线分析了改性前后Ni-MOF的微结构形貌和电化学性能。结果表明,经过超声处理后,Ni-MOF的比表面积从40.6 m^2·g^-1增加到65.8 m^2·g^-1,平均孔径从12 nm增加到22 nm。在0.5 A·g^-1电流密度下,超声处理后Ni-MOF电极比电容从420 F·g^-1增加到515 F·g^-1,提高了22.6%,电荷转移电阻明显降低,从25.11Ω降低到15.51Ω。因此,物理超声法可有效改善Ni-MOF表面微/纳米结构,提高其电化学性能。     

Innovative focused ultrasound-based sealing method of flexible packaging films—Principles and characteristics

A key process to package goods is the closure procedure. It ensures the good protection against the environment and vice versa. Ultrasonic sealing presents the advantage of converting locally ultrasound into heat, which is optimal for temperature sensitive goods. The disadvantages remain, however, the equipment cost, the noise generation, and the process sensitivity to materials. It is necessary to develop a sealing process to decrease the acquisition cost of the sealing equipment and cover a wide range of polymer films. This paper focuses on a new sealing method based on high-intensity focused ultrasound. The principles and characteristics of this process are discussed and underpinned with experimental results. Both the acoustic and thermal effects of the sealing process are summarized. A study of the process parameter impact on the seam strength in static and dynamic operating is proposed. Low-density polyethylene films with a carrier layer of bi-oriented polypropylene and polyethylene terephthalate are used. A first test bench generates point-shaped seam. The heat generation is recorded with an infrared thermography system. A second test bench, a horizontal form fill and seal machine, produces longitudinal seams. The seam quality is controlled by tensile test and tightness test. A quick heating of the polymer films is found. Point seams and longitudinal seams are successfully generated. The seams behave similarly to the ones generated with ultrasonic sealing process. However, the sealing velocity is limited to 3 m/min. This work provides a summary of the characteristics and principles of the new sealing method in packaging applications.     

超声波辅助淀粉提取分离工艺研究进展

超声波辅助提取分离工艺具有绿色、清洁、高效的特点,具有解决淀粉生产行业发展瓶颈问题的潜力。文章综述了影响超声波辅助提取分离工艺的因素及其在不同淀粉生产工艺中应用所得淀粉的得率和品质特性,以期为超声波辅助提取分离淀粉提供一定的理论参考和技术支持。超声波辅助提取分离适合于谷物淀粉,不适用于豆类和根茎类淀粉。