降钙素原乳胶增强免疫比浊法与免疫荧光法的相关性

目的探讨乳胶增强免疫比浊法与免疫荧光法定量检测降钙素原(PCT)的分析性能。方法乳胶增强免疫比浊法采用美国贝克曼库尔特公司AU5800全自动生化分析仪,免疫荧光法采用mini VIDAS全自动荧光免疫分析仪,检测相应配套高值、低值质控品,计算日内及日间的精密度,检测相应试剂非同批号定值标准品的偏倚程度,对2组检测方法的相关性进行分析评价。结果乳胶增强免疫比浊法检测PCT高值质控品日内精密度及日间精密度分别为2.89%、3.84%,低值质控品日内精密度及日间精密度分别为1.81%、3.77%;免疫荧光法检测PCT高值质控品日内精密度及日间精密度分别为2.42%、3.83%,低值质控品分别为2.03%、3.43%;乳胶增强免疫比浊法检测PCT高值定值标准品与低值定值标准品的偏倚分别为3.30%、-2.49%,免疫荧光法检测PCT高值定值标准品与低值定值标准品的偏倚分别为2.88%、3.63%;乳胶增强免疫比浊法在检测范围内线性良好(Y=1.028 1 X-0.289 4,R2=0.994 7),免疫荧光法在检测范围内线性良好(Y=1.079 8 X+0.179 4,R2=0.992 8),2种方法相关性良好(Y=0.357 2 X+0.284 5,R2=0.994 2)。结论乳胶增强免疫比浊法检测PCT性能良好,灵敏度高,操作简便,且由于其成本低,更值得临床推广应用。     

Roche Cobas E601电化学发光分析仪检测降钙素原的方法学评价

目的:对Roche Cobas E601电化学发光分析仪检测降钙素原(PCT)进行方法学评价.方法:通过Roche Cobas E601测定PCT的精密度、准确度、分析测量范围和携带污染率来评价其性能.结果:低、高值批内精密度的变异系数(CV)分别为1.16％、0.51％,批间精密度的CV为2.98％、1.96％;测定4份定值校准品的检测结果与靶值的偏倚为-5.26％ ～ 3.16％;线性为0.039 ng/mL ～ 86.325 ng/mL;携带污染率为0.019％.结论:该系统检测性能能够满足PCT的测定要求.     

罗氏Cobas E602全自动电化学发光分析仪检测贫血指标的方法学性能验证

目的验证Cobas E602全自动电化学发光免疫分析仪检测贫血指标的方法学性能。方法按照美国临床实验室标准化协会（CLSI）推荐的方法测定叶酸、铁蛋白及VitB12的精密度、正确度、线性范围、灵敏度、生物参考区间、携带污染率等,并进行验证。结果 Cobas E602全自动电化学发光免疫分析仪检测叶酸、铁蛋白及VitB12的批内、日间精密度变异系数分别为3.27%-4.72%和3.65%-4.95%;高、低值校正品的检测结果与靶值的相对偏倚（%）在-5.3%-4.2%之间;测量范围与厂家提供的测量范围相近;叶酸、铁蛋白及VitB12的测量数值与仪器厂家提供的参考区间符合率分别为92.50%、90.70%及93.20%;仪器检测的携带污染率为0.02%-0.18%。结论 Cobas E602全自动电化学发光免疫分析仪检测叶酸、铁蛋白和VitB12的方法学性能良好。     

血清降钙素原分析仪性能评价及在临床中的应用

目的探讨mini VIDAS型全自动降钙素原（PCT）分析仪的精密度及在临床中的应用分析。方法采用微型全自动免疫荧光分析仪（mini VIDAS型）,比对6个浓度血样,得出标准偏差（s）和变异系数（CV）;并对4270例怀疑感染的住院患者进行PCT测定（分六个等级分别是小于0.05、0.05-0.1、0.11-0.5、0.51-2.0、2.1-10和大于10ng/mL）。结果 mini VIDAS型分析仪批间、日间精密度比较差异无统计学意义（P〉0.05）。在4 270例PCT检测患者中阳性组935例,低风险组854例,阴性组2 481例,检测结果与临床诊断基本相符。结论 mini VIDAS型PCT分析仪精密度高、重复性好,临床检出率高,可准确判断感染情况。     

M16磁敏免疫分析仪检测性能评价

目的对M16磁敏免疫分析仪的检测性能进行评价。方法选择2018年5月在重庆医科大学附属永川医院就诊的门诊和住院患者静脉肝素抗凝血液标本30份,采用心肌肌钙蛋白I(cTnI)、肌红蛋白(Myo)、肌酸激酶同工酶(CK-MB)(磁敏免疫法)检测试剂盒,通过定值质控品对M16磁敏免疫分析仪的精密度、线性性能和正确度进行评价,同时采用Roche Cobas E602全自动电化学发光检测仪测定Myo、CK-MB水平,进行相关性分析。结果 M16磁敏免疫分析仪精密度变异系数(CV)≤15%,cTnI、Myo、CK-MB的线性相关系数r≥0.99,测定相对偏倚≤15%,均符合仪器厂商的声明性能;测定结果和电化学发光法检测结果间具有良好的相关性,Myo和CK-MB的R2分别为0.984和0.986。结论作为第3代POCT产品,M16磁敏免疫分析仪可为临床医师提供快速、准确、可靠的临床决策支持。     

罗氏Cobas 8000 e602检测性激素6项的性能验证

目的 对罗氏Cobas 8000 e602电化学发光免疫分析仪(简称Cobas 8000检测系统)测定性激素6项的性能进行验证和评估.方法 对Cobas 8000检测系统测定孕酮、雌二醇、黄体生成素、促卵泡生成素、泌乳素及睾酮的正确度、精密度、参考区间、线性范围进行验证分析.结果 孕酮低值、高值批内精密度分别为2.35％、2.25％;雌二醇低值、高值批内精密度分别为2.16％、1.95％;黄体生成素低值、高值批内精密度分别为1.37％、1.25％;促卵泡生成素低值、高值批内精密度分别为0.92％、0.89％;泌乳素低值、高值批内精密度分别为1.10％、0.76％;睾酮低值、高值批内精密度分别为1.29％、1.58％,均<1/4TEa(25％).孕酮低值、高值批间精密度分别为2.5％、1.1％;雌二醇低值、高值批间精密度分别为3.3％、1.8％;黄体生成素低值、高值批间精密度分别为1.1％、0.5％;促卵泡生成素低值、高值批间精密度分别为1.0％、0.4％;泌乳素低值、高值批间精密度分别为0.8％、0.9％;睾酮低值、高值批间精密度分别为1.7％、0.9％,均<1/3TEa(25％).性激素6项正确度验证成绩≥80％,正确度通过;验证线性范围各相关系数R2均>0.99,均呈线性.验证参考区间的通过率=测定结果在参考范围内的例数/总测定例数×100％,均≥90％,各参考区间均可信.结论 Cobas 8000检测系统的主要性能均达到相关标准的要求,能够满足临床需求.     

两种方法检测降钙素原的正确度性能评价

目的采用免疫荧光层析法与电化学发光法定量检测降钙素原（PCT）,对其正确度性能进行评价。方法连续检测10d,每天取不同浓度的6～7份临床血清样本,其中高值18份,中值22份,低值28份,共计68份样本分别用广州万孚生物技术服务有限公司出品的免疫荧光层析法仪器与配套试剂（实验方法）和罗氏公司的电化学发光法仪器与配套试剂（比较方法）定量检测PCT,分析两种方法检测结果的偏倚和相关性,评估两种方法的可比性。结果两种检测方法配对t检验,t=0．479,单侧t0．05（67）=1．668,故P〉0．05;直线回归检测,相关系数0．992,P〈0．05,回归方程：y=0．960X＋0．257,检测结果具较好一致性,PCT医学决定水平0．5ng／mL和2．0ng／mL处的总符合率为97．06％。结论免疫荧光层析法与电化学发光法检测PCT结果具高度相关性和一致性,能够满足临床检测的基本要求。     

乳胶增强免疫比浊PCT试剂在ADVIA 2400系统应用的性能评估及与电化学发光系统一致性研究

目的评价国产乳胶增强免疫比浊法降钙素原(PCT)诊断试剂在西门子ADVIA 2400系统上应用的性能。方法参考美国临床实验室标准化委员会(CLSI)指南对乳胶增强免疫比浊法PCT诊断试剂在西门子ADVIA 2400系统检测的精密度、准确度及线性范围进行性能验证,同时与参考方法(电化学发光法)进行一致性比较。结果乳胶增强免疫比浊法在西门子ADVIA 2400系统上测定PCT低值和高值质控品的批内精密度分别为5.5%、2.3%,批间精密度分别为6.6%、3.1%,总精密度分别为6.6%、3.9%。PCT浓度在0.19～49ng/mL范围的线性良好(r=0.995 7)。乳胶增强比浊法与电化学发光法的Passing-Bablok回归方程为Y=0.846 X+0.0772(r=0.989 4)。两种方法在cut-off值分别为0.5、2.0、10.0ng/mL时的Kappa值分别为0.742、0.893、0.921,西格玛(σ)值为3.5,两方法在低、高PCT浓度处的质量目标指数(QGI)分别为0.68、2.41。结论国产乳胶增强免疫比浊PCT试剂在ADVIA-2400系统上应用符合性能验证标准,但采用六西格玛标准,该方法在精密度和准确度方面尚需进一步改进。     

某品牌国产化学发光仪检测降钙素原的性能评价

目的对某品牌国产化学发光仪检测降钙素原(PCT)的性能进行评价。方法在新产业MAGLUMI4000化学发光仪上检测PCT,对其精密度、线性、携带污染率进行评价,并与梅里埃(mini-VIDAS)酶联免疫荧光法检测PCT进行相关性分析。结果化学发光法检测PCT的低、中浓度样本的CV_(批内)分别为1.56%、2.23%;CV_(批间)分别为2.30%、3.05%。PCT在0.5~98.0ng/mL浓度范围内线性良好(Y=0.997 22 X+0.173 77,r~2=0.998 12)。携带污染率为0.89%,样本间交叉污染小。新产业MAGLUMI4000化学发光仪检测系统与梅里埃mini VIDAS荧光免疫分析仪检测系统测定PCT的结果呈明显相关(Y=1.004 X+0.005 59,r~2=0.999 58)。结论新产业MAGLUMI4000化学发光仪检测系统测定PCT的性能良好,可供临床使用。     

上海地区儿童快速免疫层析法cTnⅠ参考区间的建立

目的采用快速免疫层析法检测上海地区儿童末梢血心肌肌钙蛋白(cTnⅠ)水平,初步建立儿童末梢血cTnⅠ的参考区间,为临床诊断儿童心肌损伤提供实验室依据。方法选取7个月～12岁儿童240名,采用快速免疫层析法检测其末梢血cTnⅠ。先进行方法学评估(准确性、精密度、最低检测限、线性范围验证、方法比对),然后采用百分位数法确定cTnⅠ的参考区间。结果快速免疫层析法检测高、低值质控品的结果分别为4.73和0.49 ng/mL,均在质控品标示的预期范围内;低值质控品日间和日内精密度[变异系数(CV)]分别为5.97%和5.36%,高值质控品日间和日内精密度(CV)分别为6.35%和7.14%,均符合要求(CV10%);最低检测限为0.02 ng/mL;线性范围为0.028～26.400 ng/mL;与化学发光法的相关性良好(r=0.988),检测cTnⅠ的第99百位数值为0.1 ng/mL,第99百位数值的不精密度为18.5%。采用百分位数法计算99%参考区间上限值为0.5 ng/mL,同时结合试剂说明书中标示的参考区间(0.3 ng/mL),确定基于快速免疫层析技术的儿童末梢血cTnⅠ参考区间:0.3 ng/mL为阴性、0.5 ng/mL为阳性。cTnⅠ为0.3～0.5 ng/mL时需进一步检查,以判断是否有心肌损伤。结论初步建立了基于快速免疫层析法的上海地区儿童末梢血cTnⅠ的参考区间。     

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.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.