不同转氨酶试剂和质控品的相关与偏倚

目的以常用的两种ALT试剂对血清样本和质控血清的ALT测定结果进行对比分析,以期得出不同ALT试剂之间的相关性及正确评价相应质控品。方法用两种ALT试剂测定血清样本和质控血清,记录检验结果,对两种试剂进行相关性和偏倚估计。结果在进行血清样本ALT测定时,两种试剂测定结果的预期相对偏倚在线性范围内可以被接受;对不同定值和不同批号的质控品测定ALT浓度时,两种试剂存在较大的差异。结论科华东菱和英科新创两种ALT试剂在测定血清样本ALT时,测定结果相关性良好,应严格选择适当的质控品。     

两种方法检测Lp(a)的结果比对及偏差评估

目的通过两种方法检测血清Lp（a）浓度的对比分析，探讨不同检测方法之间血清Lp（a）结果的偏倚。方法依据美国临床实验室标准化委员会EP9-A文件要求，每天留取患者新鲜血清8份，分别用免疫透射比浊法和胶乳增强免疫比浊法测定血清Lp（a）浓度，共测定5d，记录检验结果，对两种方法进行相关分析和偏倚估计。结果在进行患者新鲜血清样本Lp（a）测定时，通过直线相关回归分析r^2—0.96，〉0．95，表明两种方法相关性良好，测定结果的相对偏倚在线性范围内能被接受，其结果具有可比性，但胶乳增强免疫比浊法在线性、稳定性、灵敏度等方面比常规免疫比浊法好；在测定不同的质控品Lp（a）时，两种方法测定结果的相对偏倚可达40.0％以上。结论两种方法在测定血清样本Lp（a）时，测定结果的相对偏倚在线性范围内能被接受；在测定不同的质控品时，其相对偏倚随产品不同而不同，最大可达40．0％。     

两种间接法电解质试剂的对比研究及偏倚评估

目的 血清K^＋，Na^＋，Cl^-，Ca^2＋检测在分别以Beckman原装试剂和国产试剂进行测定时的对比研究和偏倚评估。方法 依据原美国临床实验室标准化委员会EP9-A文件，每天取临床样本8份，分别用两种试剂Beckman-Coulter SYNCHRON LX20生化仪上测定样本K^＋，Na^＋，Cl^-，Ca^2＋共测定5d，记录检验结果，对两种试剂进行偏倚估计。结果 在进行患者新鲜血清样本电解质测定时，两种试剂测定K^＋，Na^＋，Cl^-，Ca^2＋的决定系数分别为0．998，0．9942，0．997，0．9864；在测定不同的质控品时，两种试剂测定结果的相对偏倚最大为4．7％。结论 Beckman和国产两种间接法电解质试剂在LX20生化仪上测定血清K^＋，Na^＋，Cl^-，Ca^2＋时，检测结果的相关系数为正相关，相关程度高，线性回归方程良好。临床实验可用国产试剂替换进口试剂。     

两种检测方法测定质控血清及样本血清白蛋白的结果分析

目的 了解白蛋白（ALB）两种测定方法测定质控血清和临床样本血清存在的偏倚及省室间质评ALB成绩不理想的原因。方法 用浪甲酚绿（BCG）和溴甲酚紫（BCP）两种方法。每天测定10份临床样本．每份测定两次。共测定5天，记录检测结果，进行相关分析和偏差的评估，同时进行质控血清的测定。结果 不同厂家、不同批号质控血清偏差不同。有的质控品相对偏倚达45．6％；临床样本血清ALB的浓度分别为50、40、30、20g几时。各阶段的相对偏倚分别为5.8％、11．3％、20％、38％。结论 用溴甲酚绿（BCG）和溴甲酚紫（BCP）两种方法测定质控血清白蛋白时，由于方法学的不同和基质原因，测定结果偏倚不同，有的质控品偏倚很大；用两种方法测定临床标本时，随白蛋白浓度的降低，偏倚逐渐增大。     

方法学比较实验的设计及对两种白蛋白测定法的比较

目的 分析溴甲酚绿（ＢＣＧ）法和溴甲酚紫（ＢＣＰ）法进行血清样本白蛋白（ＡＬＢ）测定时的偏倚。方法 依据美国国家临床实验室标准协会ＥＰ９－Ａ文件,每天取临床样本８份,分别用两种方法测定样本白蛋白含量,共测定５ｄ,记录检测结果,去除离散点,计算线性方程和相关系数,进行偏倚估计。结果 在进行患者新鲜血清样本白蛋白测定时,ＢＣＧ法和ＢＣＰ法测定结果的预期相对偏倚在ＡＬＢ浓度＝５０ｇ／Ｌ时为１．８％,白蛋白＝４０ｇ／Ｌ时为５．５％,白蛋白＝３０ｇ／Ｌ时为１１．６％;在测定质控品白蛋白时,两种方法测定结果的相对偏倚可达３６％。结论 ＢＣＧ和ＢＣＰ方法在测定血清样本白蛋白时,测定结果的相对偏倚随白蛋白浓度降低而增加;在测定质控品时,其相对偏倚随产品不同而不同,最大可达３６％。     

两种检测方法测定质控血清及样本血清白蛋白的结果分析

目的 了解白蛋白(ALB)两种测定方法测定质控血清和临床样本血清存在的偏倚及省室间质评ALB成绩不理想的原因.方法 用溴甲酚绿(BCG)和溴甲酚紫(BCP)两种方法,每天测定10份临床样本,每份测定两次,共测定5天,记录检测结果,进行相关分析和偏差的评估,同时进行质控血清的测定.结果 不同厂家、不同批号质控血清偏差不同,有的质控品相对偏倚达45.6%;临床样本血清ALB的浓度分别为50、40、30、20g/L时,各阶段的相对偏倚分别为5.8%、113%、20%、38%.结论 用溴甲酚绿(BCG)和溴甲酚紫(BCP)两种方法测定质控血清白蛋白时,由于方法学的不同和基质原因,测定结果偏倚不同,有的质控品偏倚很大;用两种方法测定临床标本时,随白蛋白浓度的降低,偏倚逐渐增大.     

同一校准品不能直接用于校正非配套检测系统

目的：观察同一校准品能否直接用于校正非配套检测系统。方法：以罗氏试剂及程序、罗氏cfas校准品、日立7060全自动生化分析仪为标准检测系统，用Beckman校准品的标示值直接校正奥林帕斯AU2700／中生试剂检测系统和Beckman Delta CX7／Beckman试剂检测系统；然后以新鲜病人混合血清作为临时校准品，Beckman校准品经标准系统准确度传递后，把Beckman校准品的标示值转换为校正“奥林帕斯AU 2700／中生试剂”测定系统的实际校正值，再用此值校正AU2700／中生试剂系统，在上述四个检测系统上同时测定40份新鲜病人血清的尿素(UREA)、肌肝(Cr)、糖(GLU)、钙(Ca)、镁(Mg)、尿酸(UA)、甘油三酯(TG)、胆固醇(CHOL)，并对所得结果进行均值及线性回归分析。结果：Beckman校准品的标示值直接校正AU2700／中生试剂系统时，各指标的均值与标准系统的均值相对偏倚超过5％的有UREA、Cr、Ca、TG，分别为7．89％，11．70％，9．00％，16．80％。Beckman Delta CX7检测系统准确度传递后的AU2700／中生试剂系统与标准测试系统相比，各指标均值相对偏倚均小于5％，同时线性回归良好。结论：同一校准品不能直接用于校正非配套检测系统，但同一校准品经过标准系统准确度传递后可用于校正其它非配套检测系统。     

Beckman校准品经检测系统量值传递后用于校正AU2700/中生试剂系统

目的 探讨Beckman校准品经检测系统量值传递后用于校正“奥林帕斯AU2700／中生试剂”测定系统的可行性。方法 以罗氏试剂及程序、cfas校准品、日立7060全自动生化检测系统，通过患者新鲜混合血清量值传递，将Beckman校准品的标示值转换为校正“奥林帕斯AU2700／中生试剂”测定系统的实际校正值。同时，用检测系统、Beckman校准品量值传递前后的“AU2700／中生试剂”系统分别测定40份患者新鲜血清的尿素(Urea)、肌肝(Cr)、糖(Glu)、钙(Ca)、镁(Mg)、尿酸(UA)、三酰甘油(TG)、胆固醇(CHOL)，并对测定结果进行统计分析。结果 Beckman校准品的标示值与Beckman校准品在“奥林帕斯AU2700／中生试剂”测定系统中校正值的相对偏倚超过5％的项目有Urea、Cr、Ca、TG。同时，分析40份患者新鲜血清生化结果，量值传递后的Beckman校准品校正“奥林帕斯AU2700／中生试剂”测定系统时，其结果与检测系统结果更接近。结论 Beckman校准品经检测系统量值传递后用于校正“奥林帕斯AU2700／中生试剂”系统时，其检验结果与检测系统结果具有可比性。     

不同试剂盒血清胱抑素的性能比较研究

目的：探讨不同试剂盒在血清胱抑素的性能比较研究。方法分别选取3种不同的试剂盒，采取重医附一院体检科体检的血清样品，采用H itachi 7600‐010型全自动生化分析仪对上述血清样品进行检测，分别进行精密度试验和试验机基质效应的评估。结果（1）上述3种试剂盒对四种质控品的变异度在1．70％～5．42％之间，Aa试剂盒对质控品④的变异系数5．42％大于其说明书上的最大批间差，其余各项均符合说明书的要求；（2）②、④标示值得部分检测值出现相对偏倚，其中②检测的Bb低于允许范围，④检测的Aa、Bb低于允许范围；（3）分别利用上述3个试剂盒比较对上述厂家质控品系统和新鲜血清进行检测，其中Bb试剂盒较Aa试剂盒的偏倚在～5．0％～14．0％之间，Cc检测系统的偏倚较Aa检测系统的偏倚在～5．0％～39．0％之间， Cc试剂盒较Aa试剂盒高低不等，各项试剂盒之间比较无差异，差异无统计学意义；新鲜血清的Aa试剂盒与Bb试剂盒之间比较有差异，差异有统计学意义（P＜0．05）；Bb试剂盒较Aa试剂盒平均偏差为11．3％，将上述20份血清检测数据进行线性回归，结果呈现出良好的相关性。结论研究的3种不同试剂盒的检验结果的变异性均在正常值范围内，仅有个别的存在偏差，适用不同厂家的试剂盒必须配备相应的质控品，不同厂家的血清 CysC应有自己的参考值范围。     

定值质控血清及血清酶校准品在室内质控中的溯源性研究

目的探讨定值质控血清及血清酶校准品在室内质量控制中的溯源性，建立与国家相关机构关联、实用且准确的方法。方法在0LYMPUSAU-400全自动生化分析仪上用酶校准品以单点定标方式定标和用定值质控血清以两定标方式定标，与理论校准参数KS值3种方法分别测定室内质控血清中的丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、碱性磷酸酶（ALP）、肌酸激酶（cK）、乳酸脱氢酶（LD）、7一谷氨酰转移酶（y-GT）等6种酶的活性，同一批号的室内质控血清分装后在3种参考系统内测定，比较其X±S和相对偏倚（D％）。结果定值质控血清校准的碱性磷酸酶（ALP）、乳酸脱氢酶（LD）与酶校准品差异有统计学意义（P％0．05），丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、肌酸激酶（CK）、7-谷氨酰转移酶（y-GT）差异无统计学意义（P〉0．05）；理论KS值的6种酶与酶校准品差异有统计学意义（P％0．05）。结论定值质控血清校准与血清酶校准品校准结果相近，用两者进行室内质控血清酶的测定方法具有较好的溯源性，在无血清酶校准品时，可以用定值质控血清代替以校准理论KS值。     

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.