血清降钙素原水平判断血流感染细菌类型的价值研究

目的 分析患者血清降钙素原(procalcitonin,PCT)水平对区分革兰阳性(G+)菌和革兰阴性(G-)菌所致血流感染的价值.方法 选取2010年10月～2012年3月期间具有感染症状的入院病人,经细菌培养,119例静脉血培养阳性的患者(G+菌感染者53例,G-菌感染者66例)纳入实验组,39例静脉血培养阴性但其它部位标本培养阳性的患者设为对照组.通过对患者血清PCT和血浆内毒素(endotoxin,ETX)水平测定,分析G+菌及G-菌感染血流后,患者体内PCT分布水平是否存在差异,并探讨该差异与ETX的相关性.结果 经秩和检验,G-菌组与G+茵组比较,PCT水平差异具有统计学意义(G-菌38.60±74.82 ng/ml,G+菌4.08±8.65 ng/ml,n=119,u=6.202,P＜0.001),根据受试者工作曲线(receiver operating characteristic curve,ROC),当界值(cutoff value)设定为5.56 ng/ml时,血清PCT水平区分G-与G+菌所致血流感染的灵敏度为74.20％,特异度为86.80％;以G-及G+分组细菌后,组内菌种比较,PCT水平差异均无统计学意义(P＞0.05).经直线相关分析,血流感染患者血清PCT水平与对应血浆ETX浓度之间有正的直线相关关系(P＜0.01).结论 G-菌所致的血流感染患者血清PCT水平高于G+菌所致的血流感染,ETX是引起PCT水平增高的一个重要原因,血清PCT水平测定有助于区分G+菌及G-菌所致的血流感染.     

血清降钙素原水平在血流感染中的临床价值

目的探讨血清降钙素原(PCT)水平在血流感染患者中的临床价值。方法回顾性分析我院568例同时送检PCT检测和血培养的结果,其中有效研究对象538例;比较PCT水平与血培养结果的关系,同时比较PCT在革兰阴性菌、革兰阳性菌及真菌之间的差异;选取多次行PCT检测的血培养阳性患者,并依据3周内转归分为好转组、迁延组及死亡组,比较不同转归患者PCT差异。各组间PCT差异比较采用秩和检验;预后分析中采用Fisher’s精确概率法。结果血培养阳性患者PCT值[3.39(0.69~6.52)μg/L]明显高于血培养阴性患者[0.31(0.09~1.48)μg/L],差异有统计学意义(P0.05);G-菌、G+菌及真菌感染患者PCT分别为4.39(1.80~10.85)μg/L、1.98(0.42~4.05)μg/L及0.62(0.39~3.98)μg/L,差异有统计学意义(P0.05);根据受试者工作特征曲线(ROC),PCT临界值设定为3.315μg/L时,区分G-菌与真菌血流感染的灵敏度为67.9%,特异度为75.0%;设定为4.1μg/L时,PCT区分G+菌与G-菌血流感染的灵敏度为57.7%,特异度为76.5%;46例多次PCT检测血培养阳性患者中,PCT呈下降趋势时患者预后较好。结论血清PCT水平的检测有助于快速排除和诊断血流感染,同时有助于区分G-菌、G+菌及真菌所致的感染;动态监测PCT变化趋势有助于患者预后的判断。     

降钙素原在鉴别血流感染菌种中的作用

目的比较血清降钙素原(PCT)在G-杆菌和G+球菌血流感染中的差异及其诊断价值。方法回顾性分析本院急诊科血流感染患者,血培养结果阳性且为单一的G-杆菌或G+球菌菌株,并检测了血清PCT浓度,所有患者的疾病严重程度通过APACHEII评分、SOFA评分、住院时间、死亡率来评价。根据菌株不同分为G-杆菌感染组(59例)、G+球菌感染组(24例)。比较2组患者入院时的PCT水平。绘制PCT对血流感染菌种鉴别的受试者工作特征曲线(ROC曲线),根据曲线下面积(AUC)来评价其对血流感染菌种鉴别的价值。结果 G-杆菌和G+球菌2组血流感染患者在年龄、性别、疾病严重程度、住院时间方面比较差异无统计学意义(P>0.05)。2组血流感染患者的感染来源比较差异具有统计学意义(P<0.05);G-杆菌感染多来源于消化系统,G+球菌感染多来源于呼吸系统。从血液培养的菌株分布来看,引起血流感染的G-杆菌以大肠埃希氏菌、肺炎克雷伯氏菌为主,G+球菌以金黄色葡萄球菌、溶血性葡萄球菌为主。G-杆菌组PCT高于G+球菌组,差异有统计学意义(P<0.05)。ROC曲线分析显示,PCT曲线下面积AUC=O.680(95%CI:0.555-0.806)、AUC与area=0.5的差异具有统计学意义(P<0.05);血清PCT值的最佳截断值为2.5 ng/m L,此时Youden指数最大(0.309),灵敏度为55.9%,特异度为70.5%。结论血清PCT浓度在G-杆菌引起血流感染中明显增高,故早期检测有诊断意义。     

早期联合测定炎症因子对不同病原菌血流感染的鉴别诊断价值

目的 探讨早期联合测定外周血降钙素原(PCT)、C反应蛋白(CRP)和内毒素对不同病原菌血流感染的脓毒症鉴别诊断的临床价值.方法 回顾性分析2012年1月至2013年12月首都医科大学附属世纪坛医院ICU血培养阳性的脓毒症患者152例,根据血培养结果分革兰阴性杆菌与革兰阳性球菌及真菌血流感染组,分别观察患者入科后第1天的外周血PCT、CRP、内毒素和三者联合后的水平在早期诊断的价值.结果 (1)共收集血流感染病例152例,革兰阴性菌共93例(61.18％),以肺炎克雷伯氏菌、鲍曼不动杆菌、大肠埃希氏菌、洋葱伯克霍尔德菌、铜绿假单胞菌为主;革兰阳性菌43例(28.29％),金黄色葡萄球菌13例(8.55％);真菌16例(10.53％).(2)对三组患者的炎症指标进行比较,革兰阴性菌组内毒素阳性60例(64.52％),革兰阳性菌及真菌组均未检测到内毒素阳性值.革兰阴性菌PCT为7.760 (3.365,28.585) ng/mL,革兰阳性菌为0.705 (0.265,3.225) ng/mL,真菌为1.245 (0.543,1.998) ng/mL,三组间差异具有统计学意义;CRP在革兰阴性菌为(126.01±66.53) mg/L,革兰阳性菌(77.58±54.21) mg/L,真菌(140.14±71.21) mg/L,血流感染真菌组升高更为明显.(3)比较各细菌组的受试者工作特征曲线(ROC曲线)的诊断效应,区分革兰阳性菌组和真菌组的ROC曲线显示,AUCPCT+CRP=0.791,PCT截点为0.92 ng/mL,CRP截点为68.00 mg/L,敏感性为50％,特异性为95.5％;区分革兰阴性菌组和真菌组的ROC曲线显示:AUCPCT+CRP+LPS=0.947,PCT截点为2.16ng/mL,CRP截点为94.10 mg/L时,内毒素阳性为截点,敏感性为82.8％,特异性为100％;区分革兰阴性菌组和革兰阳性菌组的ROC曲线显示AUCPCT+CRP+LPS=90.2％,PCT截点为2.68 ng/mL,CRP截点为106.5 mg/L,内毒素阳性为截点,敏感性为74.2％,特异性为97.7％.结论 重症监护病房的血流感染仍以革兰阴性菌为主,早期联合外周血PCT、CRP、内毒素检测,与单一炎症因子相比,可明显提高对不同病原菌血流感染脓毒症患者早期诊断的敏感性和特异性.     

不同病原体血流感染血清降钙素原水平研究

目的分析血流感染早期血清降钙素原(PCT)水平与血流感染病原体的相关性,为临床预测病原体种类提供依据。方法收集北京同仁医院2018年1月至2020年10月526份血培养阳性样本为研究对象,其中革兰阳性球菌238株、革兰阴性杆菌245株、真菌28株和厌氧菌15株,统计患者第一次血培养阳性采血时间之前24 h内血清PCT水平。通过绘制不同病原体血流感染患者PCT水平的受试者工作特征(ROC)曲线,确定预测不同病原体血流感染的PCT水平最佳截断值。结果革兰阳性球菌血流感染患者PCT水平为0.76(0.26,3.93)ng/mL,革兰阴性杆菌血流感染患者PCT水平为4.86(0.97,24.94)ng/mL,真菌血流感染患者PCT水平为0.80(0.30,1.44)ng/mL,厌氧菌血流感染患者PCT水平为2.96(2.25,5.07)ng/mL。预测革兰阳性球菌、革兰阴性杆菌、真菌、厌氧菌血流感染的PCT水平最佳截断值分别为1.38、7.83、1.22、3.76 ng/mL。结论 PCT水平与不同种类病原体存在一定关系,根据PCT水平可以预测病原体的种类。     

降钙素原在重症监护室血流感染患者鉴别菌种和预后判断中的作用

目的：探讨降钙素原在重症监护室（ICU）血流感染患者鉴别菌种及预后判断中的作用。方法选择ICU 血流感染患者共69例,检测所有研究对象血清降钙素原（PCT）水平,进行血培养、菌种鉴定,并随访30 d 患者预后,评价 PCT 在 ICU 血流感染患者早期鉴别菌种与预后判断中的作用。结果革兰阴性菌感染患者的 PCT 水平显著高于革兰阳性菌和真菌感染的患者,真菌感染的患者 PCT 水平显著高于革兰阳性菌感染患者（均 P ＜0．01）。在区分革兰阳性菌与革兰阴性菌和革兰阴性菌与真菌时计算 PCT 的界值分别为1．94 ng/mL 和4．35 ng/mL,能获得最好的灵敏度和特异性与 ROC 曲线下面积,分别为0．87和0．59。革兰阴性菌和真菌感染的死亡患者血清 PCT 水平显著高于存活患者（P ＝0．003、0．013）,而在革兰阳性菌感染的患者中差异无统计学意义（P ＝0．473）。结论PCT 在 ICU 血流感染患者鉴别菌种和预后判断中具有较好的预测作用,值得临床借鉴。     

降钙素原和内毒素对急诊脓毒性休克早期血流感染的预测价值分析

目的:应用Logistic回归模型和受试者工作特征曲线(ROC曲线)探讨血清降钙素原(PCT)及内毒素对急诊脓毒性休克早期血流感染的预测价值。方法:选取我院2017-06—2019-06期间急诊脓毒性休克患者作为研究对象,根据血培养结果分为血流感染组64例(观察组),阴性组56例(对照组)。分析观察组的病原菌种类,比较两组患者的体温、休克指数,血清白细胞计数(WBC)、PCT、内毒素的含量。同时构建二分类Logistic回归模型和ROC曲线,分析各项指标与血流感染的相关性,并通过ROC曲线下面积(AUC)、敏感度、特异度等评价不同指标的预测价值;进一步把观察组分为革兰阴性菌组(G-组)和革兰阳性菌组(G+组),比较PCT和内毒素对病原菌分型的诊断价值。结果:观察组的病原菌以革兰阴性菌最常见,约占70%;两组患者的体温、休克指数及WBC相比较,差异无统计学意义(P0.05),观察组的血清PCT及内毒素水平显著高于对照组(P0.05);Logistic回归显示PCT和内毒素对血流感染的预测均有统计学意义(P0.05),血清PCT和内毒素预测血流感染的临界值分别为17.56 ng/ml、0.85 EU/ml(中度内毒素血症),其敏感度和特异度分别为(65.60%,88.90%)、(76.60%,91.70%);进一步研究发现,内毒素对革兰阴性菌预测的敏感度和特异度显著高于PCT,PCT对革兰阳性菌预测的敏感度和特异度优于内毒素(P0.05)。结论:检测血清PCT和内毒素水平均有利于鉴别早期急诊脓毒性休克患者是否存在血流感染,其敏感度、特异度均较高;另外,内毒素在预测革兰阴性菌感染方面要优于PCT,PCT在预测革兰阳性菌方面价值更高。     

降钙素原和白细胞介素-6水平在细菌性血流感染鉴别诊断中的价值

目的 探讨血清降钙素原(PCT)和白细胞介素-6(IL-6)水平对鉴别革兰阳性(G+)菌、革兰阴性(G-)菌血流感染的价值.方法 将2017年12月至2019年12月于广东省人民医院治疗的血流感染患者195例纳入研究,其中G-菌感染者90例作为G-组,G+菌感染者105例作为G+组.另外,选取同期就诊的非血流感染者10...     

血培养革兰阳性与阴性菌感染血清降钙素原水平比较

目的探讨患者血清降钙素原（PC T ）水平对区分血培养阳性及革兰阳性（G＋）菌和革兰阴性（G-）菌所致感染的临床应用价值。方法通过对患者血标本细菌培养阳性的标本进行革兰染色及同时检测患者血清PC T水平,比较PC T浓度在革兰阴性细菌及阳性细菌之间的差异,并对其进行敏感性和特异性分析。结果血培养阴性患者PCT为（1．02±0．65）ng/mL ,血培养阳性患者PCT为（8．55±3．62）ng/mL ;G -菌感染组血清PCT含量为（10．78±4．83） ng/mL ;G＋菌感染组血清PCT含量为（4．22±3．16） ng/mL ,两者比较差异有统计学意义（P＜0．05）。结论血清PC T水平测定可作为快速排除和诊断血流感染的辅助检测指标,同时有助于迅速区分G＋菌及G-菌所致的血流感染。     

血清降钙素原在血流感染中的应用价值

目的评价血清降钙素原(PCT)在鉴别血流感染中的不同革兰染色反应病原菌的临床应用价值。方法选择2013年1月至2014年10月该院住院治疗患者血培养呈阳性的132例感染性病例,均为单一菌株感染,分为革兰阳性组(46例)和革兰阴性组(86例);另选取66例血培养阴性的局部感染患者为对照组。比较各组患者的PCT水平。结果革兰阳性组患者血清PCT浓度为(3.16±0.69)ng/mL,革兰阴性组PCT浓度为(11.04±2.31)ng/mL,对照组患者血清PCT水平为(0.97±0.32)ng/mL,3组患者PCT水平两两比较,差异均有统计学意义(P0.001)。根据受试者工作特征(ROC)曲线得到PCT区分革兰阴性与阳性感染的诊断界值为5.25ng/mL,敏感度为90.5%,特异度为75.6%。结论 PCT对不同类别致病菌感染具有一定的诊断价值,有助于区分革兰阴性与革兰阳性的菌株感染。     

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.     

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.