比对校准献血前ALT初筛结果对降低血液报废率的影响

目的提高献血前ALT初筛检测质量,减少血液报废/血源流失。方法采用干式生化法/速率法同时检测ALT值为50 U/L左右的自配质控物,比对分析每台式生化仪检测值,计算出适用于每台仪器"新临界值",用调整后的"新临界值"判定干式生化法ALT检测值,提高干式生化法ALT检测的准确性。结果运用该方法后,献血后ALT报废率从1.36%降至0.27%,血源流失从10.5%降至7.6%。结论通过比对校准献血前干式生化法ALT检测值,使结果更准确,降低血液报废率,减少血源流失,在血站系统有很好的适用性和推广价值。     

临床实验室干式生化检测项目测量不确定度的评估与分析

目的 根据西安市儿童医院干式生化室内质控和卫健委临检中心室间质评的累积数据,评价13项干式生化检测项目的测量不确定度。方法收集西安市儿童医院检验科2018年6～12月,13项干式生化检测项目的室内质控数据(生理水平和病理水平)和2017～2019年间干式生化室间质评的数据,依据Nordtest准则,计算与精密度和偏移相关的相对不确定度分量,评估合成相对标准不确定度和扩展相对不确定度。结果 13项干式生化检测项目的扩展相对不确定度范围为5.23%～17.41%,其中丙氨酸氨基转移酶(ALT)的生理水平扩展相对不确定度最大(17.41%),总蛋白(TP)的生理水平扩展相对不确定度最小(5.23%)。尿素(BUN)的生理水平和总胆固醇(TC)的病理水平的扩展相对不确定度不符合实验室目标不确定度,分别为10.93%和10.76%,其余项目均符合。结论 Nordtest准则适用于儿童医院临床实验室干式生化检测项目测量不确定度的评估,能更好地为临床提供结果咨询。     

献血前丙氨酸氨基转移酶初筛意义的探讨

目的探讨在献血者献血前使用干式自动生化仪快速初筛丙氨酸氨基转移酶（ALT）的意义。方法使用Reflotron干式生化仪及其配套测试条在采血前初筛献血者ALT。献血后应用全自动生化仪采用速率法对献血者血液进行ALT检测。同时,比较施行ALT初筛前后因单项ALT不合格的报废率。结果使用干式化学法在献血前对献血者进行ALT初筛后,血液的报废率显著降低。结论献血前对献血者初筛ALT是一种筛除ALT异常的有效方法,能够最大限度地保留献血者和减少宝贵血源的浪费。     

ALT干式化学法与全自动速率法检测的对比试验

目的 探讨干式化学法在无偿献血者采血前ALT检测的适用性.方法 用干式化学法分析仪及ALT测试条与全自动生化分析仪速率法及ALT测定试剂盒,分别对300名无偿献血者进行ALT检测,对2种方法检测结果进行对比分析;同时,取3种不同定值ALT质控血清,分别用干式化学法与全自动速率法进行精密度对比实验.结果 干式化学法与全自动速率法检测ALT结果有相关性,300名无偿献血者ALT检测总符合率为99.0％;干式化学法与全自动速率法检测3种不同定值ALT质控血清精密度较好,变异系数(CV)均＜10％,但干式化学法检测ALT精密度差于全自动速率法精密度.结论 干式化学法操作简单、快速方便,可用于街头献血屋或流动献血车献血者采血前的ALT检测.     

采供血机构不同检测系统对ALT检测结果比对研究

目的评估丙氨酸氨基转移酶(ALT)偏倚是否能被献血者筛查及血液检测标准接受。方法校准品和质控物组成的检测系统为目标检测系统比较方法(X),实验室内半自动生化分析仪待评检测系统(Y1),实验室内酶标板速率法待评检测系统(Y2),献血屋半自动生化分析仪待评检测系统(Y3),献血车干式生化分析仪待评检测系统(Y4);每天在测定标本前测定2种靶值(41.1U/L,120 U/L)室内质控物各1次,连续20 d,标本采用献血者新鲜血液经干化学试纸条Y4系统测试后血清在其它系统中检测。计算试验方法(Y)与比较方法(X)之间的相对偏差(SE%),以美国临床实验室修正法规(CLIA'88)规定的1/2允许误差(10%),作为检测系统测定结果的可比性和临床可接受标准;同时以批间CV值CLIA'88 1/3允许误差(6.7%)为不精密度可接受标准。结果 Y2、Y4与X不精密度比较差异有统计学意义(P0.05),除Y4检测ALT质控物水平1(40.9 U/L)不精密度6.7%外,其他均6.7%,系统误差部分不能被临床接受。Y1和Y3与X不精密度比较差异无统计学意义(P0.05),质控物批间CV值6.7%。结论应对不同ALT检测系统进行方法学比对,判断其可接受性能,以保证检测结果的可比性和实验结果的准确性,减少血液报废和献血者流失。     

干式生化法用于无偿献血者初筛的可行性探讨

目的　探讨干式自动生化仪快速初筛献血者ALT的有效性。方法　使用Reflotron干式生化仪及其配套测试条在采血前初筛检测献血者ALT :取 30 μl全血置于测试条的样本区检测 ,2min内读取结果 ,以 <4 0U(卡门氏单位 )为合格。同时与全自动生化仪的检测结果做准确性对比 ,以罗氏生化正常失控血清做重复性及稳定性分析。结果　使用干式化学法初筛后 ,血液报废数显著降低 ;该方法显示出良好的准确性、重复性及稳定性。结论　干式生化仪化学法是一种筛除ALT异常献血者的有效方法。     

应用干式化学法初筛检测献血者ALT效果分析

目的探讨利用干式化学法初筛检测献血者ALT的效果,减少献血后血液报废。方法比较无偿献血前ALT初筛检测进行与否,对血液ALT检测不合格的影响。结果经干式化学法初筛检测后献血者血液ALT报废率为0.19%,为初筛前ALT淘汰率的9.5%,P〈0.005。结论推广应用干式化学法在献血前对献血者进行ALT筛查,能有效降低血液报废,有利于保留献血者。     

生化室间质评物在提高生化结果准确度的有效利用

目的提高自建生化检测系统的精密度及准确度,使检测结果准确、可靠,具有可比性。方法将参加四川省生化室间质量评价的剩余室间质评物分装后冰冻保存,待回报结果确定后复溶重测。结果对室间质评物重测值、上报结果及回报靶值这三者进行比较分析,针对结果在允许范围之外的项目,分析质控失败原因并及时处理。结论充分利用剩余生化室间质评物,很大程度上提高了实验室自建生化检测系统的准确度及实验室间结果的可比性。     

国产干式生化分析仪快速检测ALT在无偿献血者筛选中的应用

采血前预筛丙氨酸氨基转移酶(ALT)成为当前采供血系统降低因ALT导致的血液报废率的有效策略.应用干式化学法或者速率法预筛关于其应用效果报道很多,但是关于国产干式生化分析仪及其试剂在ALT检测中的应用及结果的符合性报道很少.作者选取30例标本,分别用国产干化学法与大生化法进行检测比对,报道如下.     

丙氨酸氨基转移酶快速检测在无偿献血中的应用

目的探讨干式化学法在献血前丙氨酸氨基转移酶（ALT）快速初筛的作用,减少因ALT升高而导致的血液报废。方法对泰州市中心血站姜堰分站未使用干式化学法筛查与使用干扰化学法筛查后无偿献血ALT升高引起的血液报废情况进行比较。再随机选取献血者100人,对其进行献血前ALT检测并与速率法进行对比分析。结果筛查后不合格人数占总不合格数比例从71.1%下降到47.6%;干式化学法与速率法相关性良好（r=0.906 2）。结论干式化学法准确快速,干式化学法在献血前的筛查是十分必要的,对减少因ALT升高而导致的血液报废也是十分有效的。     

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.