丙型肝炎病毒抗体诊断试剂盒(EIAgen HCV Ab Kit)的可信度分析

目的 分析丙型肝炎病毒(HCV)抗体酶联免疫吸附试验(ELISA)诊断试剂盒(EIAgen HCV Ab Kit)的可信度.方法 应用考核试剂EIAgen HCV Ab Kit和参比试剂Ortho HCV 3.0 ELISA对2 881例样本进行检测,检测结果不一致时,应用重组免疫印迹试验(RIBA)确证.所用试剂为RIBA(R)HCV 3.0 SIA或核酸试验(NAT),并对结果进行综合分析.结果 2 881例样本中,阳性样本333例,阴性样本2 539例,9例不确定的样本被剔除.考核试剂检测真阳性333例,无假阴性结果,真阴性2 527例,假阳性12例.考核试剂灵敏度为100.00%,高于参比试剂;特异性为99.53%,略低于参比试剂.考核试剂对部分国内常见HCV基因型的灵敏度为100.00%,对于非HCV感染的病毒性肝炎、自身免疫性疾病及妊娠样本具有良好的特异性,特异性均为100.00%.溶血、脂血样本对考核试剂检测结果无影响.考核试剂阳性预测值为96.52%,阴性预测值为100.00%,符合率为99.58%.考核试剂S/CO≥5.9的样本301例,其中用参比试剂检测S/CO≥3.8占88.70%;考核试剂S/CO＜5.9的样本32例,其中用参比试剂检测S/CO＜3.8占87.50%.结论 试剂EIAgen HCV Ab Kit灵敏度100.00%,特异性较好,是一种优质的抗-HCVELISA试剂,尤其适用于阳性样本的筛选.采用EIAgen HCV Ab Kit试剂检测样本,当S/CO≥5.9时,样本的阳性预测值比较高.     

丙型肝炎病毒抗体筛查阳性结果确证方案的探讨

目的明确抗-HCV酶免检测结果与确证阳性结果之间的相互关系,以期建立简便、经济的血液筛查实验室抗-HCV确证试验方案。方法使用重组免疫印迹试验结合核酸检测方法对134份酶免抗-HCV阳性样本确证,初步探讨2或3种抗-HCV酶免试剂(Ortho、Murex和科华联合复检的S/Co值与阳性预期值的关系及不同试剂组合检测的阳性预期值。结果134份样本中,92份真阳性,5份可疑,其余均为阴性。Ortho和Murex试剂的S/Co与阳性预期值呈正相关,当S/Co≥3.8时,阳性预期值分别可达98.33%和97.78%。Murex联合科华、Ortho联合科华以及3种试剂同时检测为阳性时的阳性预期值为100%;Ortho联合Murex的阳性预期值为98.48%,与上述其它2或3种试剂组合比较,差异无统计学意义(P>0.05)。结论2种或3种酶免试剂联合复检的确证方案优于美国CDC推荐的S/Co≥3.8方案。在常规血液筛查实验室,可以选择3种抗-HCV试剂中的任2种同时复检,先行对抗-HCV阳性标本确证,对无法确证的样本再作重组免疫印迹试验分析。     

广州献血人群抗-HCV ELISA检测S/CO值与确证试验结果的相关性

目的研究广州献血人群抗-HCV ELISA检测试验S/CO值与确证试验(NAT和RIBA)结果的相关性。方法采用进口(Abbot或Ortho)和国产(科华)抗-HCV ELISA试剂对2009年2月～2012年4月广州血液中心采集的无偿献血者血浆标本作抗-HCV检测,从中随机收集664份双试剂呈反应性的血浆标本进一步作确证试验;使用ROC曲线分析3种ELISA试剂的S/CO值与确证试验结果的相关性。结果 ROC曲线分析显示3种ELISA试剂检测的S/CO值与确证试验结果具有相关性:以Youden指数最大时的S/CO值为最佳阈值,Abbot、Ortho及科华试剂分别为3.234、4.460和6.976,均可预测>95%的确证试验阳性结果。结论不同试剂具有各自的最佳S/CO阈值,可以通过S/CO值预测HCV感染确证试验的阳性结果。     

HBsAg和抗HCV EIA检测试剂质量监控的简易方法

一、材料①EIA抗-HCV和HBsAg检测试剂盒．②2NCU／ml抗-HCV或1ng／ml和1万ng／mlHBsAg参考血清（卫生部临床检验中心）．③抗-HCV和HBsAg阴性血清各10份（自留）．④伯乐450型酶标仪．二、方法1.将EIA抗-HCV或HBsAg检测试剂量室温平衡．2．用2NCU／ml抗-HCV或1ng／ml和1万ng／mlHBsAg参考血清，以及留取的抗-HCV或HBsAg阴性血清代替检测标本，按试剂说明进行操作．3．比色读取吸光度，计算阳性阈值（Cutoff，CO）．然后计算出各检测标本的S／CO比值（S为检测标本吸光度）．S／CO比值≥1．0者为阳性，反之，S／CO比…     

HCV抗体检测临界值附近样本传播HCV风险的研究

目的用尽可能低的消耗，达到HCV感染早期诊断，尽量缩短ELISA HCV抗体检测的“窗口期”，防止和减少经输血传播丙型肝炎的风险。方法采集初次检测抗-HCV（S／CO）样本测定值／临界值0．40～0．99的样本310份，采用“HCV抗体分片段酶联免疫确认试剂盒”进行补充旁证检测，对检测阳性及可疑阳性样本再进行HCV—PCR和RIBA及HCV—cAg检测。结果310份样本共检出单片段阳性样本25份，2个片段以上阳性样本3份，共计28份。HCV—PCR阳性3份，HCV—cAg阳性4份，RIBA检测3个条带阳性2份，1个条带阳性22份。28份样本中，抗-HCV分片段、PCR、HCV—cAg以及RIBA共同阳性1份，HCV—cAg与PCR共同阳性2份，HCV—cAg和RIBA共同1份。结论加强对抗-HCV检测阴性高值样本的重视，尽量缩短ELISA—HCV抗体检测“窗口期”。     

艾滋病病毒感染对酶联免疫吸附试验试剂检测静脉吸毒人员丙型肝炎病毒抗体反应强度影响的探讨

目的探讨艾滋病病毒(HIV)感染对ELISA试剂检测静脉吸毒人员丙型肝炎病毒(HCV)抗体的影响,为HIV、HCV混合感染检测策略的提出和修改提供理论依据。方法按是否感染HIV分组对两种抗-HCVELISA试剂检测反应强度(S/CO)≥1的分布进行对比,采用SPSS 15.0软件分析。结果两组样本经两种试剂检测反应强度(S/CO)的构成差异有统计学意义(P0.05),HIV阳性组HCV抗体检测低反应强度的构成高于HIV阴性组(P0.05)。对科华试剂检测为低反应强度的标本,与用Ortho试剂检测结果的一致性在两组间差异有统计学意义(P0.05)。结论是否感染HIV对科华HCV抗体ELISA试剂及Ortho HCV 3.0 ELISA试剂反应强度均有影响。HIV感染者可能出现HCV抗体ELISA检测不确定或假阴性反应,弱阳性反应标本可增加假阳性可能。     

丙型肝炎病毒抗体试剂检测结果的可信度分析

目的分析丙型肝炎病毒抗体试剂检测结果的可信度。方法利用研制第5套抗HCV国家参考品过程中所搜集到的283份样品,用国内2家和国外4家公司生产的6种抗HCV试剂检测。6种试剂检测结果不一致的样品,用HCVRIBA试剂和HCVRNAPCR试剂作进一步确证,对结果进行综合分析。结果6种抗HCV试剂阳性符合率均>93%,阴性符合率、总符合率均>96%。6种抗HCV试剂曾出现19份假阳性样品,国外的3种抗HCVEIA试剂(DS,M4,O3)所出现的4份假阳性样品其S/CO值均<3.8,化学发光试剂(OF)所出现的8份假阳性样品除1份S/CO值为7.57以外,其余7份亦均小于3.8。国内2种抗HCVEIA试剂假阳性样品S/CO值范围分布较广,9份样品S/CO值大于3.8,6份样品S/CO值在3.8和1.0之间。6种抗HCV试剂曾出现5份假阴性样品的S/CO值在0.42～0.98之间,大多数假阴性样品的S/CO值在0.50～0.98之间。结论美国CDC对美国市场所用抗HCVEIA试剂检测可信度的分析[1]适用于国内市场上进口的抗HCVEIA试剂。而国产抗HCVEIA试剂假阳性样品S/CO值范围分布较广,对于国产抗HCV试剂可信度的S/CO值界限不应机械的套用美国CDC规定。对于国内外抗HCVEIA试剂检测时S/CO值>0.5,<1.0的高值阴性样品应注意是否为漏检。     

第三代与第四代HIV ELISA试剂应用效果分析

目的 比较第三代与第四代HIV ELISA试剂在实际工作中的检测效果.方法 对367份S/CO≥0.6的血清标本同时用第三代和第四代HIV ELISA试剂进行复检试验,复检试验阳性样本送确证实验室进行确证实验.结果 第三代HIV ELISA试剂检出阳性34份,经确证为阳性标本27份,阳性符合率79.41%;第四代HIV ELISA试剂检出阳性91份,经确证为阳性标本33份,阳性符合率36.26%.结论 第四代HIV ELISA试剂检测的敏感性高于第三代HIV ELISA试剂,阳性符合率低于第三代HIV ELISA试剂,应根据检测需要选择检测试剂.     

静脉吸毒人群中血浆抗-HCVEIA法、WB法与HCVRNA荧光定量PCR法比较

目的了解吸毒人群中抗-HCV EIA法、WB法与HCV RNA检测分析的符合性,选取适合高危人群的HCV实验室诊断策略。方法使用2种EIA试剂进行筛查试验,初检阳性者用另一种抗体试剂复检和用FQ-PCR(荧光定量PCR)法检测HCV RNA,抗体复检阳性的样品用HCV WB检测试剂进行确认。结果血清学试验115份样本初检结果阳性108份,阴性7份;对初检阳性者进行复检,结果阳性90份,阴性18份。复检阳性者使用WB确认,89份阳性,1份不确定;EIA抗-HCV结果S/CO≥3.8有71份,与WB阳性符合率为98.6%。EIA复检阳性样本中HCV-RNA检出率为82.22%,复检阴性样本中有HCV RNA的检出率为77.78%(14/18)。结论抗-HCV并不与HCV RNA同时出现。吸毒人员HCV感染的检测,在EIA筛查基础上,对阴性样本检测HCV-RNA,阳性样本用WB试验进行确认,确保检测的准确性。     

2个酶免疫分析系统检测抗HCV抗体的重复性和诊断阈值分析

目的分析2个酶免疫分析系统检测抗丙型肝炎病毒(HCV)抗体的重复性和阳性预测值≥95%时的信号/临界值(S/CO)比值。方法分别用Addcare ELISA 1100全自动酶免疫分析系统(简称Addcare系统)和TECAN+FAME组合系统,以间接酶联免疫吸附试验(ELISA)检测抗HCV抗体,重组免疫印迹分析(RIBA)确认抗HCV抗体。收集高、中、低3个水平的样本,在一批检测内重复检测20次(孔),计算分析内精密度;在10 d以上时间内单次(孔或管)重复进行20批检测,计算分析间精密度。收集202份血清,以RIBA确证试验结果为金标准,用受试者工作特征(ROC)曲线分别确定2个检测系统检测抗HCV抗体的最佳诊断阈值(S/CO比值),并分别确定2个检测系统检测抗HCV抗体的阳性预测值≥95%时的S/CO比值的范围。结果 Addcare系统和TECAN+FAME组合系统检测抗HCV抗体的分析内变异系数(CV)分别为5%、8%、10%和3%、7%、8%,分析间CV分别为8%、12%、15%和6%、10%、13%。2个酶免疫分析系统检测抗HCV抗体的最佳诊断阈值(S/CO比值)分别为3.20和2.90。2个酶免疫分析系统检测抗HCV抗体的阳性预测值≥95%时的S/CO比值范围分别为≥2.41和≥2.57。结论国产Addcare系统和进口TECAN+FAME组合系统检测的结果重复性好,符合率高。酶免疫分析系统ELISA检测抗HCV抗体具有各自最佳的S/CO比值,且S/CO比值与确证试验阳性有一定的相关性,可用S/CO比值预测抗HCV抗体阳性。研究确定酶免疫分析系统检测抗HCV抗体最佳诊断阈值和阳性预测值≥95%时的S/CO比值有助于提高检测结果的可靠性,减少须进行确证试验的样本数。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.