产品校准品不确定度水平对互换性评价结果的影响

目的观察产品校准品不确定度水平对互换性评价结果的影响。方法以总胆红素为例,评价A厂家产品校准品的互换性。建立测量血清总胆红素的参考测量程序和厂家测量系统;同时测量3.9~717.4μmol/L 26份单人份血清和A厂家产品校准品;按目前我国市场上总胆红素产品校准品的不确定度水平(0.57%~10.0%),采用国际临床化学和检验医学联合会(IFCC)互换性评价更新方案评价校准品不确定度水平对其互换性的影响。结果建立的总胆红素参考测量程序测量GBW09184和GBW09185的结果分别为(108.1±1.8)μmol/L和(44.8±0.8)μmol/L;测量浓度为84.3μmol/L的质控品10次,测量变异为0.55%。26份单人份血清,参考测量程序和厂家测量系统的测量结果分别为5.0~679.7μmol/L和3.9~717.4μmol/L,A厂家产品校准品的测量结果分别为80.9和77.6μmol/L。按总胆红素产品校准品的相对不确定度分别为1.0%、5.0%计算,A厂家产品校准品在2个相同测量程序间的互换性评价结果存在差异。结论产品校准品的不确定度水平影响互换性评价结果。     

血清总胆红素改良参考测量程序的复现及性能评价

目的 复现血清总胆红素改良参考测量程序并评价其性能。方法 根据德国汉诺威临床化学研究所推荐的参考方法及相关文件，复现血清总胆红素的改良参考测量程序，对其正确度、精密度、线性范围、不确定度等进行评估。采用Doumas参考方法和改良参考测量程序检测40份临床血清样本，评价两种方法的一致性。结果 改良参考测量程序检测国家一级标准物质GBW09184、GBW09185的浓度为107.03、44.10μmol/L,相对扩展不确定度为2.1%、2.5%,偏倚为-0.99%、-1.13%,2020RELA样本的测量值在其等效范围内，总不精密度<1.5%,测量线性范围为11.55～443.96μmol/L。40份血清标本测量结果与Doumas参考方法可比，Passing-Bablok回归分析方程为Y=0.029 9+1.001X,斜率的95%CI为0.995 8～1.004 6,截距的95%CI为-0.197 2～0.187 5,相关系数r=0.999。结论 成功复现血清总胆红素改良参考测量程序，改良程序使用摩尔吸光系数代替标准溶液进行校准，操作方便，分析性能提高，可实现临床常规实验室总胆红素检...     

循环酶法测定同型半胱氨酸的性能验证

目的评价循环酶法检测同型半胱氨酸(Hcy)的分析性能。方法参考美国临床和实验室标准化协会(CLSI)系列文件和有关文献,对Hcy试剂盒测定血清Hcy的精密度、正确度、分析测量范围、临床可报告范围等方面进行验证和评价,并将实验结果与厂家(宁波美康生物科技股份有限公司)(NingBo Medical System Biotechnology Co.,Ltd)提供的分析性能或公认的质量指标进行比较。结果循环酶法检测血清Hcy批内CV分别为1.26%、0.84%,总CV分别为1.36%、1.32%,低于厂家声明的允许总不精密度(10%);两个浓度校准品检测结果与靶值的相对偏倚分别为3.69%、0.69%,均符合相关的质量要求(小于10%);分析测量范围为3.38~51.81μmol/L,厂家线性范围为小于50μmol/L;最大稀释度为1∶3,临床可报告范围为3.38~155.43μmol/L。结论宁波美康生物科技有限公司生产的Hcy试剂盒的主要分析性能达到了厂商声明的性能和有关的质量要求,适合临床应用。     

血清总胆红素厂家校准品不同示值来源对互换性评价结果的影响

目的观察血清总胆红素厂家校准品不同示值来源对互换性评价结果的影响。方法按血清总胆红素厂家校准品3种示值来源(a.厂家校准品证书示值,b.Doumas参考方法赋值,c.有证标准物质传值)分别给某厂家校准品定值,并校准该厂家常规测量系统,分别命名为A、B、C常规测量系统。采用Doumas参考方法和A、B、C常规测量系统同时测量该校准品和26份不同浓度单人份血清样本;按国际临床化学和检验医学联合会(IFCC)工作组互换性更新方案评价该校准品的互换性。结果a方式下校准品不具备互换性,b和c方式下校准品互换性评价结果基本一致且均具备互换性。结论血清总胆红素厂家校准品不同示值来源对互换性评价存在一定的影响,具备溯源性的厂家校准品可获得相对一致的互换性评价结果。     

GUF评定血清TB参考测量程序测量不确定度初探

目的探讨基于《测量不确定度表示指南》(简称GUM)的不确定度框架法(GUF)评定Doumas血清总胆红素(TB)参考测量程序测量结果不确定度的可行性。方法应用国际检验医学溯源联合委员会(JCTLM)推荐的Doumas血清TB参考测量程序,对国际临床化学和检验医学联合会(IFCC)参考实验室外部质量评价计划(RELA)样本进行测定,分析测量结果各不确定度分量来源,同时对各分量分别进行评定,计算相对合成不确定度、标准不确定度和扩展不确定度。结果 2014年RELA-A和RELA-B样本TB浓度分别为67.33、31.99μmol/L,相对合成标准不确定度分别为1.57%、1.61%,标准不确定度分别为1.06、0.52μmol/L,扩展不确定度(取95%可信区间,k=1.96)分别为2.07、1.01μmol/L。结论利用GUF评定血清TB参考测量程序测量结果不确定度的方法可满足临床实验室对血清TB参考测量系统的要求。     

重庆地区健康人群总胆红素和直接胆红素参考范围的调查

目的了解重庆地区健康人群血清总胆红素和直接胆红素参考值水平,分析其与性别和年龄的关系。方法采用全自动生化分析仪用改良重氮盐法对该地区健康者2 731例进行血清总胆红素、直接胆红素测定,并与操作规程的参考值范围进行对比分析。根据年龄大小将健康人群按性别各分为4组,依次为30岁组、30~45岁组、46~60岁组、60岁组,进行组间对比分析。结果重庆地区2 731例健康者总胆红素参考范围为5.05~23.9μmol/L,直接胆红素为0~7.72μmol/L。按照分组,男性各年龄段总胆红素参考范围分别为4.23~24.65、4.86~25.32、5.17~24.11、5.17~24.11μmol/L,直接胆红素参考范围分别为0.51~7.85、0.34~7.94、0.46~7.64、0.64~8.01μmol/L。女性各年龄段总胆红素参考范围分别为4.93~22.13、5.24~23.20、5.93~21.37、4.26~24.56μmol/L,直接胆红素参考范围分别为0.29~6.71、0.00~7.28、0.00~7.39、0.36~7.40μmol/L。不同性别之间胆红素水平有明显不同,男性血清总胆红素及直接胆红素水平均高于女性(P0.05)。结论重庆地区健康人群血清总胆红素水平与操作规程参考值范围有较大差异,建议各地区实验室根据不同年龄、性别建立各自的参考值范围。     

不同评价方法对标准物质互换性评价结果的影响

目的观察不同评价方法对标准物质互换性评价结果的影响。方法以A、B、C 3个血清总胆红素候选标准物质、甲厂家校准品D的互换性评价为例,采用血清总胆红素参考方法和甲常规方法同时测量A、B、C、D 4个待评价样本和无溶血、乳糜的26份单人份血清样本的总胆红素含量。分别采用EP30-A、EP14-A3和国际临床化学和检验医学联合会(IFCC)互换性评价更新方案3个互换性评价方法评价待评价样本的互换性,EP30-A和EP14-A3方法的互换性评价判断依据为标准物质应落在Y预测值的±95%置信区间内,IFCC互换性评价更新方案中的互换性评价判断依据为标准物质的偏移/差±不确定度应落在医学允许偏移的固定范围内(该研究设定为5%)。比较采用3个不同判断依据对标准物质互换性评价结果的影响。结果A、B、C、D 4个样品参考方法和常规方法的测量结果分别为108.10、44.60、53.16、200.70μmol/L和94.93、38.27、48.70、189.50μmol/L;26份人血清样本的总胆红素浓度范围分别为4.69~679.73μmol/L和4.2~684.17μmol/L;A、B、C、D 4个样品采用EP30-A、EP14-A3方法评价时均具有互换性,但采用IFCC互换性评价更新方案评价时仅有A和C 2个样品具有互换性。结论评价方法不同,相同样品的互换性评价结果有可能不同,IFCC互换性评价更新方案的评价结果更符合医学预期需求。     

太原地区健康人群血清总胆红素和直接胆红素参考范围调查

目的：了解太原地区健康人群血清总胆红素和直接胆红素参考值水平。方法：采用全自动生化分析仪、重氮试剂法对该地区健康人群640人作血清总胆红素和直接胆红素测定,然后按年龄、性别分组,并与文献报道的各地参考值范围分别进行对比分析。结果：太原地区640例健康人群总胆红素参考范围（x-±1.96s）分别为：男性6.66-27.78μmol/L,女性6.24-19.96μmol/L,总体5.43-25.11μmol/L。直接胆红素参考范围（x-±1.96s）分别为：男性0.23-3.45μmol/L,女性0-2.77μmol/L,总体0-3.22μmol/L。结论：太原地区健康人群血清总胆红素水平与文献报道有较大差异,建议各地区实验室根据不同年龄、性别建立各自的参考范围。     

临床生物化学实验室测量不确定度的评估

目的通过临床生物化学实验室肌酐(Cr)测量不确定度的评估,探讨医学实验室认可工作中测量不确定度的评估方法和程序。方法以中国合格评定国家认可委员会(CNAS)提供的《测量不确定度要求的实施指南》为基础,参考其他测量不确定度指南文件,对本实验室血清Cr的测量不确定度进行评估。结果血清Cr浓度为59.65μmol/L时,所有不确定度分量影响的合成不确定度为2.69μmol/L,取95%可信区间,包含因子k=2,则血清扩展不确定度U=5.38μmol/L;排除生物学变异和分析前因素后,其他不确定度分量影响的合成不确定度为0.75μmol/L。结论我们所建立的测量不确定度评估方法简单方便,能分析不同因素对测量结果的影响程度,可用于医学实验室认可工作。     

天门冬氨酸氨基转移酶37℃参考方法的建立及其应用研究

目的通过建立37℃天门冬氨酸氨基转移酶（AST）参考方法,对酶校准品定值,探讨血清AST测定结果的准确性与可比性。方法依据国际临床化学与检验医学联合会（IFCC）推荐的参考测量程序建立AST酶催化活性参考方法,并对其精密度、线性范围和干扰因素进行方法学评价,用参考方法测定c．f．a．s多项校准液,并建立本室的参考范围。同时用参考方法对制备的酶校准品进行准确定值,按照NCCLSEP9-A方案比较40份人血清用酶校准品校准的常规方法和参考方法AST结果。结果我室初步建立的37℃ AST参考方法相应方法学参数,如下：总CV0．89％-1．12％、线性范围1．3—300U／L。AST测定结果在48U／L左右偏差超过5％的干扰物浓度分别为游离胆红素256．5μmol／L、结合胆红素205．2μmol／L;AST在165U／L左右测定结果偏差超过5％的干扰物浓度分别为游离胆红素307．8μmol／L、结合胆红素342μmol／L。血红蛋白在1g／L时对两种浓度的AST干扰均大于5％。而甘油三酯在10mmoL／L以下对两种浓度的AST的干扰仍然小于5％。用参考方法测定c．f．a．s多项校准液AST结果128．5U／L,比靶值高0．5U／L。本室参考范围AST：男性10—40U／L;女性7—40U／L。健康男女AST有显著差别（P〈0．05）。用制备的酶校准品校准的常规方法和参考方法进行比较,相关良好（r^w=0．9992）。前者结果与后者相对偏倚在±10％之内。结论我室的参考方法基本建立,采用参考方法为酶校准品定值,可以提高血清AST测定结果的准确性和可比性。     

Guns and Knives in New Mexico: Patterns of Penetrating Trauma, 1978–1993

Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.     

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.     

Interprofessional approaches to creating safe,high quality health care

Three supplementary perspectives are presented arguing that interprofessional collaboration is both necessary and desirable. Nonetheless, there are often too many serious intra-professional barriers and obstacles to interprofessional collaboration to make it successful. Some of these barriers, it is argued and illustrated, are found in the multiple ways in which professional identity is tacitly acquired and embodied in the practitioners' habitual, everyday practice. The paper then explores ways in which reflection, especially Second order reflection, can help to elucidate and overcome these obstacles, as well as increasing professional adaptability and competence.     

Systematic Reviews Published in the January 2011 Issue of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD and monthly online. The January 2011 issue (first quarterly DVD for 2011) contains 4515 complete reviews, 1985 protocols for reviews in production, and 13,521 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 641,000 randomized controlled trials, and 14,018 cited papers in the Cochrane methodology register. The health technology assessment database contains over 9300 citations. One hundred and seven new reviews have been published in the last 3 months, of which five have potential relevance for practitioners in pain and palliative medicine.     

Modified micro-superior percutaneously-assisted total hip: early experiences & case reports

Because of the extensile nature and familiarity of the standard posterior-lateral approach to the hip, a family of "micro-posterior" approaches has been developed. This family includes the Percutaneously-Assisted Total Hip (PATH) approach, the Supercapsular (SuperCap) approach and a newer hybrid approach, the Supercapsular Percutaneously-Assisted Total Hip (SuperPATH) approach. Such approaches should ideally provide a continuum for the surgeon: from a "micro" (external rotator sparing) posterior approach, to a "mini" (external rotator sacrificing) posterior approach, to a standard posterior approach. This could keep a surgeon within his comfort zone during the learning curve of the procedure, while leaving options for complicated reconstructions for the more practiced micro-posterior surgeons. This paper details one author's experiences utilizing this combined approach, as well as permutations of this entire micro-posterior family of approaches as applied to more complex hip reconstructions.     

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.     

Structure and function of "metalloantibiotics"

Although most antibiotics do not need metal ions for their biological activities, there are a number of antibiotics that require metal ions to function properly, such as bleomycin (BLM), streptonigrin (SN), and bacitracin. The coordinated metal ions in these antibiotics play an important role in maintaining proper structure and/or function of these antibiotics. Removal of the metal ions from these antibiotics can cause changes in structure and/or function of these antibiotics. Similar to the case of "metalloproteins," these antibiotics are dubbed "metalloantibiotics" which are the title subjects of this review. Metalloantibiotics can interact with several different kinds of biomolecules, including DNA, RNA, proteins, receptors, and lipids, rendering their unique and specific bioactivities. In addition to the microbial-originated metalloantibiotics, many metalloantibiotic derivatives and metal complexes of synthetic ligands also show antibacterial, antiviral, and anti-neoplastic activities which are also briefly discussed to provide a broad sense of the term "metalloantibiotics."