Relationship of serum enzyme activities to demographic variables in a healthy population

Estimations of 6 serum enzyme activities were carried out in 519 subjects rigorously screened to exclude overt and latent disease, and obesity. The mean values of AP, GOT and GPT, and CPK were higher in males than in females. A negative correlation between age and activities of GPT and CPK was observed in males, whereas in females all activities measured, except that of GPT, showed a positive correlation with age. Only 5N and HBD failed to demonstrate a positive correlation with total body weight in one or other sex. A positive correlation between social class and AP was noted in females, and some significant correlations between diastolic blood pressure and some enzyme activities were found, but no association between enzyme activity and smoking habit could be detected.Computer programs were used to generate equations expressing enzyme activity as a function of age, total body weight, social class and diastolic blood pressure for each sex independently. From these, sets of reference values were derived which encompassed 95% of the demographically-corrected values for this healthy population. A trial of AP in medical out-patient clinics, and of 3 enzymes in cases of myocardial infarction, suggested that demographically-corrected reference values for serum enzymes may be more accurate than conventional parametric normal ranges in confirming or excluding organic disease.     

Evaluation of the Vitatron automatic kinetic enzyme system.

A micro-modification of the benzophenone procedure proposed by Wallace for the determination of 5,5-diphenylhydantoin in blood is described which does not require specialised glassware and avoids the interference caused by chloroform. In the new procedure 5,5-diphenylhydantoin is extracted from blood with 1,2-dichloroethane, returned to alkali, washed with n-heptane, and oxidised with permanganate in small teflon lined screw capped test tubes containing a layer of n-heptane. The absorbance of the oxidation product (benzophenone) is measured spectrophotometrically on an expanded scale using semi micro cuvettes. The method requires 100–200 μl sample and has a detection threshold of less than 0.1 mg/100 ml.     

Relationship between symptoms and functional performance in COPD

We studied the relationships among functional performance and three symptoms--dyspnea, fatigue, and sleep difficulty--in a sample of 100 people with chronic obstructive pulmonary disease (COPD). All participants had an FEV(1) 60% or less of the predicted level for age, sex, and height. Consistent with the Theory of Unpleasant Symptoms, dyspnea correlated with both fatigue and sleep difficulty. Dyspnea and fatigue both had moderate negative correlations with functional performance, while sleep difficulty had a small nonsignificant negative correlation with functional performance. After controlling for age and oxygen use, dyspnea was the only symptom to predict variance in functional performance significantly. Of the three symptoms studied, only dyspnea was related to both the other symptoms and to functional performance. Focusing on dyspnea may be the best way to improve both symptom experience and functional performance in people with COPD.     

Relationship between multiple predictor variables and normal knee torque production

The purpose of this study was to develop predictive models relating isokinetic knee testing performance to anthropometric and demographic variables. The subjects were 134 healthy volunteers (70 female, 64 male) between the ages of 10 and 80 years. The investigators measured subjects' peak knee flexion and extension torque production at two angular velocities. Stepwise regression analyses were used to examine the relationship between each torque-dependent variable and the following potential predictor variables: age, sex, side of lower extremity dominance, height, weight, percentage of body fat, and thigh girth. The investigators generated two sets of models designed to predict preinjury knee strength. Clinicians can use one set of models by assessing predictor variables before or immediately following injury. The second set of models involves the assessment of predictor variables postinjury, excluding an assessment of percentage of body fat and thigh girth. The results indicated that peak knee torque production can be predicted with statistically significant accuracy (multiple R = .78-.87). The predictive models generated in this study can be used to establish muscle strength goals for patient rehabilitative programs.     

年龄和性别与血清肝功能相关酶的关系探讨

目的探讨健康人群血清肝功能相关酶与年龄和性别的关系。方法依据个体的年龄和性别进行分组,通过全自动生化分析仪测定血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、γ-谷氨酰转移酶(γ-GT)和碱性磷酸酶(ALP)活性。结果年龄和性别不同的群体,血清肝功能相关酶活性有所不同。对3～60岁之间相同年龄段的群体,男性血清ALT、AST和γ-GT活性均高于女性;男性血清ALP活性在50岁前高于女性,而50岁后低于女性。在3～60岁之间的相同性别群体,血清γ-GT活性随年龄增加而升高;血清ALT活性先随年龄增加而升高,40岁后随年龄增加而降低;AST和ALP活性随年龄增加会出现两次峰值。结论年龄和性别是影响血清肝功能相关酶活性的因素,血清肝功能相关酶的正常参考范围制定应考虑个体的年龄和性别差异。     

血管紧张素转换酶基因与缺血性脑卒中发病的关系

目的 探讨血管紧张素转换酶(ACE)基因与缺血性脑卒中(IS)发病的关系.方法 ①应用聚合酶链反应(PCR)和变性高效液相色谱技术筛查了454例IS患者(病例组)和334例非IS患者(对照组)ACE基因I/D多态性的分布,详细记录卒中危险因素.②选择40只SD大鼠制备低氧-窒息模型和单纯窒息模型,同时选择29只易卒中型自发性高血压大鼠(SHR-SP).检测血浆血管紧张素Ⅱ(AngⅡ)水平的变化.结果 病例组的DD、ID、II型的频率分别为22.5%、43.4%和34.1%,对照组为17.4%、45.5%和37.1%,ACE基因DD型与大动脉粥样硬化型IS相关.SHR-SP血浆AngⅡ水平[(164.49±34.58)ng/L]较正常SD大鼠[(150.92±24.92)ng/L]高,但差异无显著性(P＞0.05);窒息组和低氧-窒息组血浆AngⅡ水平分别为(382.84±62.75)ng/L和(295.90±55.07)ng/L,均显著高于正常SD大鼠水平(P均＜0.01).吸烟、酗酒群体内病例组以及伴糖尿病群体的DD型和D等位基因的相对风险率均高于相应对照组,而II型和I等位基因的相对风险率均低于相应对照组.结论 DD基因型是IS的易患因子;AngⅡ参与了低氧应激过程;ACE基因与吸烟、酗酒、糖尿病在IS的发病过程中存在协同作用.     

感染性休克患者早期氧代谢变化及其与预后的关系

目的 :了解感染性休克患者早期氧代谢变化 ,主要包括DO2 ,VO2 及动脉血乳酸的代谢状况 ,并评价其与预后的关系 ,方法 :感染性休克后患者 2 6例 ,经立即扩溶、给予血管活性药物尽早稳定循环后 ,并置Swan Ganz导管 ,平均放置时间为 76 8h ,测定CI后立即行血气分析和混合静脉血气分析 ,计算出DO2 ,VO2 并测定当时的动脉血乳酸值。结果 :全组中 12例存活 ,14例死亡 ,存活组初次DO2 及末次DO2 均明显高于死亡组 ,用初次DO2 ≥ 6 0 0ml/m2 ·min评价患者预后 ,其敏感性为 87 5 % ,特异性 5 8 3% ;存活组初次及末次VO2 相近 ,分别与死亡组初次和末次VO2 比较 ,亦无明显差异 ;存活组和死亡组初次血乳酸接近 ,均高于正常 ,存活组血乳酸值在感染性休克早期经过一段升高的过程后逐步降低 ,而后恢复到正常水平 ,死亡组却继续增高直至死亡。结论 :在感染性休克早期 ,患者存在“缺陷性氧耗”现象 ,VO2 不能作为评价患者预后的指标 ;在不使用大剂量Dopamine或Dobutamine的情况下 ,初次DO2 高者 ,预后较好 ;初次血乳酸水平不能反映预后 ,血乳酸代谢的时间过程能较好的反映预后     

Relationship between knowledge of cardiopulmonary resuscitation guidelines and performance

OBJECTIVE: Despite widespread training with CPR guidelines, CPR is often poorly performed. We explore relationships between knowledge of CPR guidelines and performance (compression rate, compression depth, compression to ventilation ratio, and ventilation volume). METHODS: Sixty professional EMTs were sampled at 26 randomly ordered EMS response stations from an urban system of 31 stations. A recording manikin and video model were used to assess performance in a standardized scenario, and a survey was used to assess guideline knowledge. Survey and performance outcomes were categorized prospectively as correct or incorrect based on the International CPR Guidelines from 2000. Relationships were modeled with logistic regression. Covariates included years of work experience, frequency of CPR performance, and ALS versus BLS EMT level. RESULTS: Compression rate was between 80 and 120 min(-1) in 56% (33/59) of trials. Compression depth was 1.5-2 in. in 39% (23/59), compression to ventilation ratio approximated to 15:2 in 42% (25/59), and ventilation volume was 800-1,200 cm(3) in 13% (8/60). Accurate knowledge of the CPR guidelines was associated with better performance of chest compression rate and compression to ventilation ratio. Adjusted OR (95% CI) were 4.6 (1.2-18.1) for compression rate, 1.7 (0.4-6.5) for compression depth, 4.5 (1.1-18.5) for compression to ventilation ratio, and 9.0 (0.2-351) for ventilation volume. CONCLUSIONS: Although accurate knowledge of guidelines is associated with increased odds of correct performance of some aspects of CPR, overall performance remains poor.     

全自动酶联免疫检测仪与手工酶联免疫检测的比对评价

目的评价Tecan Freedom Evolyzer-2200全自动酶联免疫仪与手工操作后BIO-RAD680酶标仪检测临床标本结果的一致性。方法用高浓度的乙型肝炎表面抗原（HBsAg）了解仪器的交叉污染情况,采用1IU/mL的HBsAg质控血清检测其孔间重复性和板间重复性,随机抽取50份临床标本经该仪器和手工加样操作BIORAD680酶标仪测定乙型肝炎病毒5项指标,测定结果进行比对。结果经试验该酶联免疫仪器的拖带污染在低水平,与手工操作比对50个项目指标检测结果总的符合率达96.4%。结论该仪器可以满足临床实验需要。     

肾性骨营养不良患者骨组织形态学变化与血生化指标的关系

目的:探讨肾性骨营养不良患者血生化指标与骨组织形态学有关参数的相关性,以寻找敏感性、特异性较高的无创性检查指标,评价透析患者的骨代谢情况。方法:实验于1997-07/1998-05在北京大学第一医院核医学科和肾内科完成。对15例维持性血液透析患者在作骨活检前测定血清全段甲状旁腺激素(iPTH)、骨钙素、骨特异碱性磷酸酶(BAP)、1,25(OH)2D3,作骨活检并进行骨组织形态学变化的检测,观察血生化指标与骨组织形态学有关参数的相关性。结果:iPTH与骨组织学动态指标:骨形成率、骨矿化率呈正相关(r=0.436,P<0.05;r=0.585,P<0.05);BAP与类骨质表面、类骨质面积有相关性。BAP与骨组织学静态参数的相关性较好(r=0.827,P<0.001)。1,25(OH)2D3与类骨质表面、类骨质面积呈正相关(r=0.637,P<0.05;r=0.426,P<0.05)。结论:iPTH,BAP与某些骨组织形态学参数相关性较好,iPTH值在低转化骨病间差异具有显著性意义,两者结合起来可以初步估计骨代谢状态。但以上血生化指标在不同类型的骨病中并无严格的界限,所以,骨活检仍是诊断肾性骨营养不良的金标准。     

Relationship between clinical and biologic variables and chloramphenicol pharmacokinetic parameters in pediatric patients with sepsis

OBJECTIVE: To evaluate the influence of several clinical and biologic factors on the disposition kinetics of oral chloramphenicol in pediatric patients and to determine the usefulness of this information to predict chloramphenicol serum concentrations. STUDY DESIGN: The clinical, biologic, and pharmacokinetic data of 30 consecutive pediatric patients diagnosed with sepsis and admitted to a tertiary care center were analyzed retrospectively. The patients were randomly assigned to a study group and a validation group. The model was developed by a three-step approach involving Bayesian estimation of pharmacokinetic parameters, selection of covariates by principal component analysis, and final selection by stepwise multiple linear regression. The model was tested in the study group and compared with a general population model using a prediction error analysis. RESULTS: Regression analysis revealed that weight, albumin, and white blood cell (WBC) count were the most important determinants for chloramphenicol distribution volume, whereas age, WBC count, and serum creatinine were the most important determinants for chloramphenicol clearance. The performance of the constructed population model improved significantly in terms of both bias and precision compared with the general model when tested in the validation group. CONCLUSIONS: Clinical and biologic factors may significantly influence chloramphenicol's disposition in pediatric patients with sepsis and therefore should be considered in programming dosage regimens.     

Automated kinetic assay of angiotensin-converting enzyme in serum

We have developed and validated an automated kinetic method for angiotensin-converting enzyme (EC 3.4.15.1) on the Olli C + D analyzer, modified from that of Ronca-Testoni (Clin Chem 1983;29:1093-6) with N-[3-(2-furyl)-acryloyl]-L-phenylalanylglycylglycine used as substrate. We have determined appropriate reaction conditions for the assay, verified the principal analytical reliability criteria (repeatability, reproducibility, sensitivity), and established normal reference intervals (mean +/- SD) for the enzyme's activity, using serum of normal adults (100 +/- 35 U/L, n = 150), newborns (130 +/- 27 U/L, n = 10), women taking oral contraceptives (103 +/- 30 U/L, n = 10), smokers (109 +/- 38 U/L, n = 27), and patients with sarcoidosis (220 +/- 48 U/L, n = 15).     

AP22 Speedy型全自动酶免分析系统性能验证

目的评价AP22Speedy型全自动酶免分析系统的主要性能,以期用于实验室管理机构的相关认证及认可工作,同时为仪器故障的诊断及处理提供依据。方法按照YZB/ITA 1679-2009标准,选定TORCH优生项目,对AP22Speedy全自动酶免分析系统加样精密度和准确性、携带污染率、测光值稳定性、批内测量重复性进行验证。结果 AP22Speedy全自动酶免分析系统检测TORCH优生项目质控血清的加样精密度和准确性、携带污染率、测光值稳定性、批内测量重复性均满足厂商声明范围。结论 AP22Speedy全自动酶免分析系统在加样精密度和准确性、携带污染率、测光值稳定性、批内测量重复性4个方面性能验证合格。     

Automated kinetic determination of angiotensin-converting enzyme in serum

In this automated kinetic modification of a previous method (Anal Biochem 95: 540-548, 1979) for determining angiotensin-converting enzyme (EC 3.4.15.1), 3-(2- furylacryloyl )-L- phenylalanylglycylglycine is used as the substrate. The change in absorbance at 340 nm is used to monitor hydrolysis of the substrate. The rate of hydrolysis is roughly threefold greater than with previously reported substrates, so assay time and sensitivity are improved.     

牛磺酸与心血管系统疾病的关系

Taurine is a kind of β amino acid containing sulfur, and the free amino acid that content is the highest in cells.Recent researches found that taurine is closely related to cardiovascular system.Some documents reported that taurine has apparent treatment effects on many kinds of cardiovascular diseases such as cardiomuscular necrosis,arrhythmia caused by hypercalcemia or hypocalcemia, cardiomuscular ischmia and reperfusion injury[1].It also can resist hypertension,decrease blood cholesterol,increase high density lipoprotein,prevent arteriosclerosis and decrease blood sugar,which had became the main study domain on physical function of taurine.     

Relationship between biological variation and delta check rules performance

ObjectivesThe performance of delta check rules has been considered to be dependent on the biological variation characteristics of the analyte of interest. The assumed relationships have not been formally studied. The mathematical relationship between biological variation and delta check rules is explored in this study.Design and methodsFrom the mathematical model for absolute difference delta check, the threshold for specificity and sensitivity are observed to be normalized differently. For specificity, the threshold is normalized by the within-subject biological variation (expressed as a coefficient of variation, ${\mathit{CV}}_i$), whereas for sensitivity the threshold is normalized by the between-subject biological variation (expressed as a coefficient of variation, ${\mathit{CV}}_g$). This highlights the different roles the two biological variations play in affecting the absolute difference distribution for correct and switched patient samples. Analogous to absolute difference delta checks, for relative difference delta checks, the expressions for specificity and sensitivity are scaled by ${\mathit{CV}}_i$ and ${\mathit{CV}}_g,$ respectively. However, the expressions are independent of ${\mu }_g$(the average of the population).ResultsA comparison between the mathematical model and empirical/ historical laboratory data obtained from patients was conducted for both absolute and relative difference delta checks. In general it was found that the specificity obtained from the historical laboratory data was less than the model predicted values, while on the other hand, good correspondence was obtained between the experimental sensitivity and predicted sensitivity.ConclusionsThe difference in within-subject biological variation in different patients may contribute to the observed discrepancy in predicted and empirical delta check performance.     

Relationship between clinical performance and professional self-concept in critical care nurses

Objective: To determine the relationship between clinical performance and professional self-concept in critical care nurses.Methods: This study was conducted on 308 critical care nurses. Data gathering instruments were nurses' clinical performance questionnaire (NCPQ) and nursing professional self-concept measure (NPSCM). Independent sample t-test, one-way analysis of variance (ANOVA), and Pearson correlation coefficient were used for data analyses.Results: The average age of the nurses was 33.74 ± 7.01 years. The clinical performance score of female nurses was significantly higher than male nurses. In the domain of clinical performance, clinical judgment and clinical inquiry had the highest and lowest scores, respectively. In the nurses' professional self-concept, the highest and lowest scores were awarded to the subscales of selfconfidence and staff relations, respectively. In addition, there was a significant positive correlation between self-concept and clinical performance of nurses.Conclusions: Increasing professional self-concept improves the clinical performance of critical care nurses. Professional self-concept enhancement measures are recommended to improve the clinical performance of nurses in critical care units.